Draft Final WWTP Preliminary Engineering Report (PER) May_2024

Centreville Wastewater Treatment Plant ENR Upgrade and Expansion Town of Centreville Centreville, MD May 2024

FINAL

Preliminary Engineering Report Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD Table of Contents Table of Contents ........................................................................................................................................................ i List of Tables ............................................................................................................................................................. iv

List of Figures ............................................................................................................................................................. v Appendices ............................................................................................................................................................... vii 1 Executive Summary ............................................................................................................................................1

1.1 Summary of Evaluations .............................................................................................................................7 1.2 Summary of Improvements.........................................................................................................................7 2 Background ...................................................................................................................................................... 13

2.1 Introduction .............................................................................................................................................. 13 2.2 Existing Facilities ..................................................................................................................................... 13 2.3 Objective .................................................................................................................................................. 16

2.3.1 Treatment Quality Goals ...................................................................................................................... 16 3 Project Planning ............................................................................................................................................... 18 3.1 Cost and Effectiveness Analysis ............................................................................................................. 18

3.2 Environmental Resources........................................................................................................................ 18 3.2.1 Desktop Analysis ................................................................................................................................. 19 3.2.2 Waters of the U.S. (Including Wetlands) Delineation .......................................................................... 19

3.2.3 Terrestrial Habitat ................................................................................................................................ 19 3.2.4 Coast Smart Climate Ready Action Boundary (CS-CRAB) ................................................................. 19 3.3 Location ................................................................................................................................................... 22

3.4 Population Trends .................................................................................................................................... 22 4 Existing Performance, Facilities, and Conditions ............................................................................................. 23 4.1 Location Map ........................................................................................................................................... 23

4.2 History ...................................................................................................................................................... 23 4.3 Financial Status ....................................................................................................................................... 24 4.4 Current Influent Conditions ...................................................................................................................... 25

4.5 Existing Plant Performance ..................................................................................................................... 25 4.6 Condition of Existing Facilities ................................................................................................................. 36 4.6.1 Treatment Process Overview .............................................................................................................. 36

4.6.2 Process/Equipment Assessment ......................................................................................................... 38 4.6.2.1 Influent Screening ........................................................................................................................ 38 4.6.2.2 Sequencing Batch Reactor .......................................................................................................... 38

4.6.2.3 Post Equalization Tank ................................................................................................................ 39 Page i Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD 4.6.2.4 Sludge Holding Tank ................................................................................................................... 40 4.6.2.5 Cloth Media Filtration ................................................................................................................... 40

4.6.2.6 UV Light Disinfection ................................................................................................................... 41 4.6.2.7 Effluent Pump Station .................................................................................................................. 42 4.6.2.8 Chlorine Contact Tank ................................................................................................................. 42

4.6.2.9 Chemical Addition ........................................................................................................................ 42 4.6.2.10 Existing Electrical System ........................................................................................................ 42 4.6.2.11 Existing Controls System ......................................................................................................... 43

4.6.2.12 Existing Spray Irrigation Effluent Disposal ............................................................................... 43 4.7 Water and Energy Audits ......................................................................................................................... 44 5 Need for Project................................................................................................................................................ 46

5.1 Health, Sanitation and Security ............................................................................................................... 46 5.2 Aging Infrastructure ................................................................................................................................. 46 5.3 Reasonable Growth ................................................................................................................................. 47

6 Upgrade and Expansion Alternatives ............................................................................................................... 48 6.1 Common Upgrades .................................................................................................................................. 49 6.1.1 Influent Screening ................................................................................................................................ 49

6.1.2 Influent Flow Equalization Tank ........................................................................................................... 50 6.1.3 UV Disinfection .................................................................................................................................... 50 6.1.4 Chemical Dosing .................................................................................................................................. 51

6.1.5 Review of Effluent Disposal Options ................................................................................................... 51 6.1.5.1 Year Round Stream Discharge .................................................................................................... 52 6.1.6 Biosolids Handling ............................................................................................................................... 52

6.1.7 Non-Potable Water System ................................................................................................................. 55 6.1.8 Laboratory and Administration Building ............................................................................................... 56 6.1.9 Filter and Blower Building .................................................................................................................... 56

6.1.10 Control Building ................................................................................................................................... 57 6.1.11 Electrical System Upgrades................................................................................................................. 58 6.1.11.1 Filter and Blower Building ........................................................................................................ 58

6.1.11.2 Lab Building ............................................................................................................................. 58 6.1.11.3 Pump Building (Old Control/Admin Building) ........................................................................... 58 6.1.11.4 Replacement Influent Screening.............................................................................................. 58

6.1.11.5 New Dewatering Facility .......................................................................................................... 58 6.1.11.6 New MBR Process Building ..................................................................................................... 59 6.1.11.7 General Site Electrical ............................................................................................................. 59

6.1.12 Control System Upgrades .................................................................................................................... 59 Page ii Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD 6.2 Treatment Alternative Upgrades .............................................................................................................. 60

6.2.1 Alternative 1 – Expand the Sequencing Batch Reactor ...................................................................... 60 6.2.1.1 SBR Process ............................................................................................................................... 60 6.2.1.2 SBR with Aerobic Granular Sludge ............................................................................................. 61

6.2.1.3 Effluent Filtering ........................................................................................................................... 61 6.2.1.4 Post Equalization Tank ................................................................................................................ 63 6.2.2 Alternative 2 – Conventional Activated Sludge.................................................................................... 63

6.2.2.1 Activated Sludge Process ............................................................................................................ 63 6.2.2.2 Effluent Filtering ........................................................................................................................... 66 6.2.3 Alternative 3 – Membrane Bioreactor (MBR) Activated Sludge .......................................................... 66

6.2.3.1 MBR Process ............................................................................................................................... 66 6.3 Site Plans and Schematics ...................................................................................................................... 69 6.4 Environmental Impact .............................................................................................................................. 73

6.4.1 Alternative 1 – Expand the Sequencing Batch Reactor ...................................................................... 73 6.4.2 Alternative 2 – Conventional Activated Sludge.................................................................................... 73 6.4.3 Alternative 3 – Membrane Bioreactor .................................................................................................. 73

6.5 Sustainability Considerations .................................................................................................................. 73 6.5.1 Water, Chemical and Energy Efficiency .............................................................................................. 74 6.5.2 Green Infrastructure ............................................................................................................................. 74

6.5.3 Climate Related Considerations .......................................................................................................... 74 6.6 Cost Estimates ......................................................................................................................................... 75 6.7 Design Criteria ......................................................................................................................................... 77

6.8 Land Requirements ................................................................................................................................. 78 6.9 Potential Construction Issues .................................................................................................................. 78 7 Alternative Evaluation ....................................................................................................................................... 80

7.1 Effluent Water Quality Comparison ......................................................................................................... 80 7.2 Life Cycle Cost Analysis .......................................................................................................................... 82 7.3 Non-Monetary Evaluation ........................................................................................................................ 83

8 Recommended Upgrades and Expansion ....................................................................................................... 87 8.1 Preliminary Project Design ...................................................................................................................... 87 8.2 Permit Requirements ............................................................................................................................... 88

8.3 Sustainability Considerations .................................................................................................................. 88 8.3.1 Water and Energy Efficiency ............................................................................................................... 88 8.3.2 Green Infrastructure ............................................................................................................................. 89

8.3.3 Climate Related Considerations .......................................................................................................... 89 8.4 Construction Cost Estimate ..................................................................................................................... 89 Page iii Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD

8.5 Annual Operating Budget ........................................................................................................................ 90 8.5.1 Income ................................................................................................................................................. 90 8.5.2 Annual O&M Costs .............................................................................................................................. 91

8.5.3 Debt Repayments ................................................................................................................................ 91 8.5.4 Reserves .............................................................................................................................................. 91 8.6 Project Implementation Schedule ............................................................................................................ 91

9 Project Asset Management .............................................................................................................................. 95 9.1 Inventory of Critical Assets ...................................................................................................................... 95 9.2 Condition of Critical Assets ...................................................................................................................... 95

9.3 Critical Asset Maintenance and Replacement Plan ................................................................................ 96 9.4 Critical Asset Energy and Water Efficiency Plan ..................................................................................... 96 List of Tables Table 1.1: Upgrade and Expansion of Facilities .........................................................................................................2

Table 1.2: Preliminary Construction Cost Estimate – Alternative 3 (MBR Activated Sludge) ....................................9 Table 3.1: Centreville Population Data .................................................................................................................... 22 Table 4.1: Recent Water and Sewer Income and Expenses................................................................................... 24

Table 4.2: Budgeted Water and Sewer Income and Expenses .............................................................................. 24 Table 4.3: Existing Debt Service ............................................................................................................................. 24 Table 4.4: Existing Influent Conditions at Centreville WWTP.................................................................................. 25

Table 4.5: Centreville WWTP Stream and Spray Effluent Flows ............................................................................ 25 Table 4.6: Centreville WWTP Stream Effluent BOD, TSS, TKN, and Ammonia Concentrations ........................... 26 Table 4.7: Centreville WWTP Stream Effluent Total NO + NO , TN, TP, and E. Coli Concentrations .................. 26 2 3 Table 4.8: Centreville WWTP Spray Effluent BOD, TSS, TKN, and Ammonia Concentrations .............................. 26

Table 4.9: Centreville WWTP Spray Effluent Total NO + NO , TN, TP, and E. Coli Concentrations .................... 27 2 3 Table 4.10: Existing SBR Tanks .............................................................................................................................. 39 Table 4.11: Existing Post Equalization Tank ........................................................................................................... 39

Table 4.12: Existing Sludge Holding Tank .............................................................................................................. 40 Table 4.13: Existing UV Disinfection ....................................................................................................................... 41 Table 4.14: Existing Significant Water Uses ........................................................................................................... 44

Table 4.15: Existing Major Electrical Demands ....................................................................................................... 44 Table 4.16: Recent Electrical Usage ....................................................................................................................... 45 Table 5.1: Historical Centreville Effluent Flow ......................................................................................................... 46

Table 6.1: Influent Mechanical Screen Design Basis – Alternatives 1 and 2 .......................................................... 49 Table 6.2: Influent Mechanical Screen Design Basis – Alternative 3 ...................................................................... 50 Table 6.3: UV Disinfection Replacement System Design Basis ............................................................................. 51

Page iv Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD Table 6.4: Aerobic Digester Design Criteria ............................................................................................................ 52 Table 6.5: SBR Design Basis .................................................................................................................................. 61

Table 6.6: Denitrifying Filter Design Basis .............................................................................................................. 63 Table 6.7: 5-Stage Activated Sludge Basin Design Basis ....................................................................................... 65 Table 6.8: Secondary Clarifier Design Basis ........................................................................................................... 66

Table 6.9: 5-Stage Activated Sludge Basin with MBR Design Basis ...................................................................... 68 Table 6.10: Environmental Impacts by Design Alternative for Centreville WWTP Site ........................................... 73 Table 6.11: Conceptual Construction Cost Estimates for Treatment Alternatives .................................................. 76 Table 6.12: Influent Basis of Design ........................................................................................................................ 77

Table 6.13: Effluent Basis of Design ....................................................................................................................... 78 Table 6.14: Summary of Potential Construction Issues .......................................................................................... 79 Table 7.1: BioWin® Model Influent Conditions ........................................................................................................ 80

Table 7.2: Target Secondary Effluent Water Quality Parameters ........................................................................... 81 Table 7.3: Secondary Effluent Water Quality BioWin Modeling Results – Average Conditions ............................. 81 Table 7.4: Secondary Effluent Water Quality BioWin Modeling Results – Maximum Monthly Conditions ............. 82 Table 7.5: Life Cycle Cost Analysis ......................................................................................................................... 83

Table 7.6: Non-Monetary Evaluation of Treatment Alternatives ............................................................................. 85 Table 8.1: Preliminary Project Design – Alt 3 MBR Activated Sludge ..................................................................... 87 Table 8.2: Permit Requirements .............................................................................................................................. 88

Table 8.3: Scope and Construction Cost Estimate – Alternative 3 (MBR Activated Sludge) .................................. 90 Table 8.4: Sewer System Income ............................................................................................................................ 91 Table 8.5: Annual Sewer System O&M Costs ......................................................................................................... 91

List of Figures Figure 1.1: Alternative 1 Proposed Process Flow Diagram........................................................................................4 Figure 1.2: Alternative 2 Proposed Process Flow Diagram........................................................................................5 Figure 1.3: Alternative 3 Proposed Process Flow Diagram........................................................................................6

Figure 1.4: Site Plan of ENR Upgrades and Expansion – Alternative 3 MBR Activated Sludge ...............................8 Figure 1.5: Upgrade and Expansion Schedule ........................................................................................................ 10 Figure 2.1: Centreville WWTP SBR ......................................................................................................................... 13

Figure 2.2: Centreville WWTP Existing Process Flow Diagram .............................................................................. 14 Figure 2.3: Existing Treatment Facilities (Credit: Google Earth) ............................................................................. 15 Figure 2.4: Further Existing Facilities (Credit: Google Earth) .................................................................................. 16

Figure 3.1: Environmental Resources Map ............................................................................................................. 21 Figure 3.2: Centreville Population ........................................................................................................................... 22 Page v Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report

Centreville, MD Figure 4.1: Location Map (Credit: Google Earth) .................................................................................................... 23 Figure 4.2: Stream Effluent Total Flow .................................................................................................................... 27 Figure 4.3: Spray Effluent Total Flow ...................................................................................................................... 28

Figure 4.4: Stream Effluent BOD Concentration ..................................................................................................... 28 Figure 4.5: Spray Effluent BOD Concentration ....................................................................................................... 29 Figure 4.6: Stream Effluent TSS Concentration ...................................................................................................... 29

Figure 4.7: Spray Effluent TSS Concentration ........................................................................................................ 30 Figure 4.8: Stream Effluent TKN Concentration ...................................................................................................... 30 Figure 4.9: Spray Effluent TKN Concentration ........................................................................................................ 31

Figure 4.10: Stream Effluent Ammonia Concentration ............................................................................................ 31 Figure 4.11: Spray Effluent Ammonia Concentration .............................................................................................. 32 Figure 4.12: Stream Effluent NO + NO Concentration ......................................................................................... 32

3 2 Figure 4.13: Spray Effluent NO + NO Concentration ............................................................................................ 33 3 2 Figure 4.14: Stream Effluent Total Nitrogen Concentration .................................................................................... 33 Figure 4.15: Spray Effluent Total Nitrogen Concentration....................................................................................... 34

Figure 4.16: Stream Effluent Total Phosphorus Concentration ............................................................................... 34 Figure 4.17: Spray Effluent Total Phosphorus Concentration ................................................................................. 35 Figure 4.18: Stream Effluent Geomean E. Coli Concentration................................................................................ 35

Figure 4.19: Spray Effluent Geomean E. Coli Concentration .................................................................................. 36 Figure 4.20: Sequencing Batch Reactor Sequence of Operation (Source: Aqua-Aerobic Systems, Inc.) .............. 37 Figure 4.21: SBR Tank w/Surface Mixer/Aerator and Decant Device (Credit: Aqua-Aerobic Systems, Inc.) ......... 38 Figure 4.22: Cloth Media Filter Components (Credit: Aqua-Aerobic Systems, Inc.) ............................................... 41

Figure 4.23: UV Disinfection Unit Isometric View (Credit: Enaqua) ........................................................................ 41 Figure 6.1: Belt Filter Press (Credit: Andritz) ........................................................................................................... 54 Figure 6.2: Volute Dewatering Press (Credit: Process Wastewater Technologies, LLC) ....................................... 54

Figure 6.3: Screw Press (Credit: Schwing Bioset, Inc.) ........................................................................................... 55 Figure 6.4: Existing Lab Building ............................................................................................................................. 56 Figure 6.5: Existing Filter and Blower Building ........................................................................................................ 57

Figure 6.6: Existing Control Building ....................................................................................................................... 57 Figure 6.7: Schematic of 5-Stage Process (Credit: EPA)........................................................................................ 64 Figure 6.8: Alternative 1 Proposed Site Layout ....................................................................................................... 70

Figure 6.9: Alternative 2 Proposed Site Layout ....................................................................................................... 71 Figure 6.10: Alternative 3 Proposed Site Layout ..................................................................................................... 72 Figure 8.1: Project Implementation Schedule ......................................................................................................... 92

Page vi Centreville WWTP ENR Upgrade and Expansion FINAL Preliminary Engineering Report Centreville, MD Appendices

Appendix A Cost Estimate Line Items .................................................................................................................... 98

Appendix B Existing NPDES

Stream and Spray Discharge Permits ..................................................................... 99

Appendix C Influent Sampling

Data and 9-Year Effluent Operating Data ............................................................ 100

Appendix D Major Process Equipment Catalog Information ................................................................................ 101

Appendix E Preliminary Hydraulic Profiles ........................................................................................................... 102

Appendix F Electrical Service

Sizing and Single-Line Diagrams ......................................................................... 103 Page vii Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 1 Executive Summary The Town of Centreville Wastewater Treatment Plant (WWTP) is owned and operated by the Town of Centreville and treats flows from the entire town. The Centreville WWTP was most recently upgraded and expanded in 2003,

including an upgrade of the facility to achieve biological nutrient removal (BNR) levels of treatment. The nutrient removal process at the Centreville WWTP consists of a two-tank sequencing batch reactor (SBR) with chemical addition for phosphorous precipitation and cloth media filtration. The WWTP is treating wastewater as designed and is meeting all the NPDES permit limits.

The facility has a permitted treatment capacity of 0.542 million gallons per day (MGD). The annual average daily flow (AAF) of the plant for the period 2014 through 2022 is 0.40 MGD. The most recent three calendar years, 2020-2022, averaged 0.45 MGD AAF, which is 83% of permitted capacity. The Town anticipates continued growth in the service area and may consider annexation of areas into the service area. Under the plant’s current

NPDES discharge permits, treated effluent is disposed into Gravel Run, a tributary to Corsica River, during the winter months and sprayed onto off-site irrigation fields during the warmer months.

The overall objective for this project is to expand the liquid and solids treatment and effluent disposal capacity to meet the needs of the anticipated growth, as well as meet enhanced nutrient removal (ENR) levels of treatment and continue compliance with the NPDES discharge permit. In concert with the treatment capacity expansion, the auxiliary systems, including the laboratory, office space, influent screening, and disinfection facilities will be

upgraded and modernized. In addition, sludge handling, biosolids treatment and dewatering facilities will be included. A non-potable water system will be added to the facility to allow for the use of treated effluent for on-site uses.

The condition and performance of the existing facilities were evaluated. Almost all the facilities were found to be in good operating condition. The tertiary cloth media filter has been reported as having insufficient hydraulic throughput for wet weather flows. The cloth media was replaced, and the filter has been reviewed by a manufacturer’s representative. In the evaluation of treatment alternatives, the cloth media filter would be replaced

by a deep bed denitrifying (sand) filter that will both remove particulate as well as remove nitrogen.

This Preliminary Engineering Report (PER) considers three treatment alternatives to expand the design capacity of the WWTP to 1.0 MGD as well as meet ENR treatment levels:

• Alternative 1 – SBR: Expand the existing SBR process, followed by tertiary denitrification filters,

• Alternative 2 – Conventional Activated Sludge: Replace the existing SBR system with a 5-stage ENR

activated sludge process, followed by tertiary filters (with denitrification capability),

• Alternative 3 – MBR Activated Sludge: Replace the existing SBR system with a 5-stage ENR Membrane

Bioreactor (MBR) activated sludge process.

Each alternative will require modifications to most of the existing treatment facilities, including sludge handling and expansion of the effluent disposal facilities. The expansion of the facilities capacity and upgrades to equipment will require enhancements to control and monitoring systems throughout the plant process areas. The addition of a centralized Plant Control System for monitoring and control will reduce overall operator and facilitate

collection of process data. The identification and study of the effluent disposal expansion options will be conducted separately from this PER. Table 1.1 provides a summary of the proposed modifications for Alternatives 1, 2, and 3. Figures 1.1, 1.2, and 1.3 show the proposed process flow diagrams for Alternatives 1, 2, and 3, respectively.

Based on the evaluations in this PER, Alternative 3 – MBR Activated Sludge is recommended for the upgrade and expansion of the Centreville WWTP.

Page 1 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 1.1: Upgrade and Expansion of Facilities Facility Alternative 1 – 4 SBRs Alternative 2 – Conventional Activated Sludge Alternative 3 – MBR Activated Sludge Replace existing mechanical screen with similar Upgrade screening to mechanically cleaned bar larger model rated at 4.0 MGD (peak hydraulic

Influent Screening Same as Alternative 1 rack followed by two (2) redundant 2-mm flow), modify existing concrete channel to opening center feed band screens.

accommodate.

Not required for operation but requested by the Not required for operation but requested by the Town. Convert the existing SBR process tanks to Town. Construct a new 500,000-gallon working two (2) approximately 500,000-gallon working Influent Flow capacity flow equalization tank with surface capacity each flow equalization tanks with surface Same as Alternative 2 but required for operation.

Equalization Tank aerator/mixers. Submersible pumps will pump aerator/mixers. Submersible pumps will pump flow from the influent flow equalization tank to the flow from the influent flow equalization tank to the SBRs.

5-stage activated sludge basins.

Install two (2) additional SBR tanks. Install surface mixers, removable fine bubble diffusers Not required. The existing SBR tanks will be SBR Same as Alternative 2.

and decant arms. Four (4) total 50 HP blowers converted into influent flow equalization tanks.

added to Filter and Blower Building.

Install 2-train, 5-stage conventional activated sludge process with membranes to separate solids from treated effluent. Fine bubble diffusers Install 2 train, 5-stage conventional activated to incorporate air from proposed high efficiency sludge process. Fine bubble diffusers to blowers. Anoxic and swing zones will be agitated incorporate air from proposed high efficiency with vertical mechanical mixers. Permeate

Expand the existing SBR tanks with additional Biological Reactors blowers. Anoxic and swing zones will be agitated pumps will draw effluent through membranes.

SBR tankage with vertical mechanical mixers. Low head Low head propeller pumps for internal recycle propeller pumps for internal recycle will be and return activated sludge will be installed.

installed. Waste sludge pumps will pull mixed liquor from the reactors and discharge into the aerobic digesters. Chemical cleaning facilities will be provided to clean the membranes.

Two (2) rectangular clarifiers with chain and flight sludge collection and submersible return activated Secondary Clarifiers Not required sludge (RAS) pumps installed in a sump. Sludge Not required will be wasted from the RAS forcemain into the aerobic digesters.

Provide double contained polyaluminum chloride (PACl) tank located in Filter and Blower Building Chemical Dosing for chemical phosphorus removal. Provide Same as Alternative 1 Same as Alternative 1 methanol storage and dosing facility for external carbon addition for enhanced denitrification.

Post Equalization Construct new 250,000-gallon post equalization Not required Not required Tank tank with surface agitators.

Page 2 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 1.1: Upgrade and Expansion of Facilities Facility Alternative 1 – 4 SBRs Alternative 2 – Conventional Activated Sludge Alternative 3 – MBR Activated Sludge Replace the existing cloth media filter with a continuous backwash sand filter in concrete tanks, sized to provide denitrification with the

Effluent Filter Same as Alternative 1 Not required addition of external carbon. House filter mechanical equipment and controls in a new building. Include maintenance space in building.

Install two UV disinfection units to replace UV Disinfection Same as Alternative 1 Same as Alternative 1 existing.

To be further evaluated. Options include:

• Additional spray irrigation disposal with

storage lagoon, Effluent Disposal • Relocation of the existing outfall and Same as Alternative 1 Same as Alternative 1 expand stream discharge to year round, and

• Planning for future beneficial water reuse.

Install non-potable water system within the Filter and Blower Building that draws from the UV Non-Potable Water effluent and pumps to an on-site distribution Same as Alternative 1 Same as Alternative 1 System system for applications such as spray water for influent screens, pump seal water, wash down, or yard hydrants throughout the WWTP.

Retrofit existing SBR post equalization tank and Install new aerobic digesters with ability to thicken sludge holding tank to two aerobic digesters with solids and decant liquid back to treatment ability to thicken solids and decant liquid back to Aerobic Digesters process. Digester tank will have center wall to Same as Alternative 2 treatment process. Existing process blowers will allow half of the tank offline. New blowers will

supply air. Coarse air stainless steel diffusers will supply air.

be mounted to the bottom slab.

Install new biosolids handling building for Biosolids Dewatering dewatering process. New covered sludge cake Same as Alternative 1 Same as Alternative 1 System storage area for treated biosolids.

Provide enhanced process controls with centralized monitoring and control workstation for Plant Control System Same as Alternative 1 Same as Alternative 1 operator interface. Provide capabilities to provide hub for Town wide SCADA system of utilities.

Reconfigure the Laboratory/Administration Laboratory/ Building to better utilize the space for the Same as Alternative 1 Same as Alternative 1 Administration Space laboratory uses. Provide a dedicated space for locker rooms and offices.

Page 3 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 1.1 Summary of Evaluations To improve treatment to provide ENR level effluent water quality and to expand the treatment capacity for current

and projected influent wastewater flows, three (3) alternatives were developed and evaluated. A “do nothing” alternative is not viable as the current average influent has exceeded 80% of the design treatment capacity and the effluent water quality has occasionally been adversely affected. Additionally, influent flows are projected to continue to increase in the future.

Preliminary sizing of the biological treatment process for each alternative to achieve the required effluent water quality was completed using the BioWin® process simulator (by EnviroSim).

Evaluation and comparison of each alternative is based on life cycle cost and non-monetary criteria:

• Life Cycle Cost Analysis (capital and O&M costs)

• Non-Monetary Comparison

• Energy and Water Efficiency

• Environmental Impacts

The capital costs of the three alternatives are within 8% from the least expensive Alternative 1 – SBR ($33.0 million), and the most expensive Alternative 2 – Conventional Activated Sludge ($35.5 million). The O&M costs were based on an assumed 20-year project life and resulted in life cycle costs of the three alternatives within 8% of each other, ranging from $47.9 million to $51.9 million.

Given the complexity of each alternative and the variability introduced in projecting operating and maintenance costs for a 20 year project life, the costs of the three alternatives are similar.

The non-monetary comparison indicated that Alternative 2 – Conventional Activated Sludge and Alternative 3 – MBR Activated Sludge were similar and both preferred to Alternative 1 – SBR. The ability to evolve with future regulations and technologies, and the use of the available space were key advantages for Alternatives 2 and 3, with Alternative 3 scoring higher than Alternative 2.

The treated effluent water quality of all three alternatives will be sufficient to meet off-site Class III and IV reclaimed water requirements for future consideration.

Given the smaller footprint of Alternative 3 – MBR Activated Sludge compared to the other two alternatives, the impact on the environment will be reduced. Alternative 3 will have greater flexibility to avoid the environmentally sensitive areas of the available site and have a reduced impact overall.

Alternative 3 – MBR Activated Sludge uses a permeable membrane to separate solids from the treated effluent compared to the other two alternatives using conventional sand media filter, and will produce the highest effluent quality in terms of suspended solids and turbidity.

Based on the evaluations, Alternative 3 – MBR Activated Sludge is recommended for the upgrade and expansion of the Centreville WWTP.

1.2 Summary of Improvements A site plan of the locations of the facilities that will be affected by the ENR upgrade and expansion, and approximate location of proposed facilities for the recommended Alternative 3 – MBR is shown in Figure 1.4.

Page 7 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 1.4: Site Plan of ENR Upgrades and Expansion – Alternative 3 MBR Activated Sludge The key scope items and rough order of magnitude (ROM) construction cost estimate for each improvement is summarized in Table 1.2. Given the conceptual design stage, a minus 20 percent and a plus 50 percent cost

contingency are added to the estimate. Additional cost breakdown for Alternative 3 – MBR Activated Sludge is included in Appendix A.

Page 8 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 1.2: Preliminary Construction Cost Estimate – Alternative 3 (MBR Activated Sludge) Item No. Category Cost 1 Interior Demolition (Lab, Control, and Filter and Blower Buildings) $95,000 2 Influent Screening Expansion $825,000 3 Converting Influent Flow Equalization Tanks, Aerated, with Pumping $2,019,000

4 Methanol Facility $618,000 5 UV Disinfection System $642,000 6 Non-Potable Water System $54,000 7 Dewatering Facility $2,413,000 8 Covered Cake Storage Facility $835,000 9 Lab, Control, and Filter and Blower Buildings Refurbishments $617,000 10 Existing Tank Modifications $643,000 11 Miscellaneous Process Piping and Equipment $784,000 12 MBR Process Building, MBR Equipment and Controls $5,789,000

13 Aerobic Digester Tank and Equipment $78,000 14 Electrical $4,169,000 15 Site Civil, including Yard Piping and Demolition (15% Items 1-12) $2,312,000 16 Site SCADA (5% Items 1-12) $771,000 Subtotal $22,664,000 Design Contingency (30% of Subtotal) $6,799,000 Escalation to December 2026 (4%/year) $3,678,000 Total $33,141,000 Total (Low Range -20%) $26,513,000 Total (High Range +50%) $49,712,000 The design and construction durations for the project were developed and presented in Figure 1.5.

Page 9 ID Task Name Duration Start Finish 2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 1 Centreville WWTP ENR 1655 days Mon Mon Upgrade and Expansion 3/20/23 7/23/29 2 PER Development 255 days Mon 3/20/23Fri 3/8/24 3 Start PER Update 0 days Mon 3/20/23Mon 3/20/23 3/20 4 Advertise for M/WBE 4 wks Mon 3/27/23Fri 4/21/23

5 Town Assembles 4 wks Mon 3/27/23Fri 4/21/23 Requested Information 6 Develop ENR PER 2 wks Mon 4/24/23Fri 5/5/23 Amendment 7 Town Review PER 2 wks Mon 5/8/23 Fri 5/19/23 Amendment 8 Sub Agreements 2 wks Mon 5/22/23Fri 6/2/23 9 Develop Draft PER 4 wks Mon 6/5/23 Fri 6/30/23 10 Topo Survey 4 wks Mon 6/5/23 Fri 6/30/23 11 Develop Alternatives 16 wks Mon 3/20/23Fri 7/7/23 12 Subconsultant Field Work8 wks Mon 5/22/23Fri 7/14/23

13 Develop PER 22 wks Mon 7/17/23Fri 12/15/23 14 Draft PER to Town and 0 days Mon Mon 12/18

MDE 12/18/23 12/18/23

15 Review Draft PER 8 wks Mon 12/18/23Fri 2/9/24 16 Incorporate Comments 2 wks Mon 2/12/24Fri 2/23/24 17 Finalize PER 2 wks Mon 2/26/24Fri 3/8/24 18 Develop Design Proposal4 wks Mon 12/18/23Fri 1/12/24 19 Town Reviews Design 2 wks Mon 1/15/24Fri 1/26/24 Proposal 20 ENR Upgrade Design 390 days Mon 1/29/24Fri 7/25/25 21 Project Set Up 2 wks Mon 1/29/24Fri 2/9/24 22 Design Kick Off w Town 0 days Mon 2/12/24Mon 2/12/24 2/12

23 30% Design 8 wks Mon 2/12/24Fri 4/5/24 24 30% Design Internal QA 2 wks Mon 4/8/24 Fri 4/19/24 25 30% Design to Town 0 days Mon 4/22/24Mon 4/22/24 4/22 26 Town Reviews 30% Design2 wks Mon 4/22/24Fri 5/3/24 27 30% Design Comment 0 days Mon 5/6/24 Mon 5/6/24 5/6 Review Meeting 28 60% Design 10 wks Mon 5/6/24 Fri 7/12/24 29 60% Design Internal QA 2 wks Mon 7/15/24Fri 7/26/24 30 60% Design to Town 0 days Mon 7/29/24Mon 7/29/24 7/29

31 Town Reviews 60% Design2 wks Mon 7/29/24Fri 8/9/24 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 1.5: UpgradeP aagned 1Expansion Schedule ID Task Name Duration Start Finish

2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 32 60% Design Comment 0 days Mon 8/12/24Mon 8/12/24 8/12 Review Meeting 33 Pre-Final Design 10 wks Mon 8/12/24Fri 10/18/24 34 Pre-Final Design Internal2 wks Mon Fri 11/1/24

QA 10/21/24

35 Pre-Final Design to Town0 days Mon 11/4/24Mon 11/4/24 11/4 36 Town Reviews Pre-Final 2 wks Mon 11/4/24Fri 11/15/24 Design 37 Pre-Final Design 0 days Mon Mon 11/18 Comment Review 11/18/24 11/18/24 38 Design Review Meeting 2 wks Mon Fri 11/29/24 with MDE 11/18/24 39 MDE Review 8 wks Mon 12/2/24Fri 1/24/25 40 Permitting 12 wks Mon 1/27/25Fri 4/18/25 41 Develop Bid Ready 4 wks Mon 4/21/25Fri 5/16/25

Documents 42 Bid Ready Doc Internal QA2 wks Mon 5/19/25Fri 5/30/25 43 Bid Ready Docs to Town 0 days Mon 6/2/25 Mon 6/2/25 6/2 44 Town Finalizes Funding 8 wks Mon 6/2/25 Fri 7/25/25 45 ENR Upgrade and 130 days Mon Fri 1/23/26 Expansion Bidding 7/28/25 46 Town Prepares for 4 wks Mon 7/28/25Fri 8/22/25 Advertisement 47 Advertise 12 wks Mon 8/25/25Fri 11/14/25 48 Open Bids 0 days Mon 11/17/25Mon 11/17/25 11/17

49 Bid Review 2 wks Mon 11/17/25Fri 11/28/25 50 Bid Recommendation to 0 days Mon 12/1/25Mon 12/1/25 12/1

MDE

51 MDE Bid Review 4 wks Mon 12/1/25Fri 12/26/25 52 Construction NTP 4 wks Mon 12/29/25Fri 1/23/26 53 ENR Upgrade and Exp 910 days Mon Mon Construction 1/26/26 7/23/29 54 Issue PO's 2 wks Mon 1/26/26Fri 2/6/26 55 Shop Drawing 16 wks Mon 2/9/26 Fri 5/29/26 Submittals and Review 56 Major Equipment Delivery36 wks Mon 6/1/26 Fri 2/5/27 57 Mobilize Site 0 days Mon 2/8/27 Mon 2/8/27 2/8 58 Construction 104 wks Mon 2/8/27 Fri 2/2/29

59 Substantial Completion 0 days Mon 2/5/29 Mon 2/5/29 2/5 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 1.5: UpgradeP aagned 2Expansion Schedule

ID Task Name Duration Start Finish 2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 60 Operations Process 2 wks Mon 2/5/29 Fri 2/16/29 Training 61 Commissioning and 12 wks Mon 2/19/29Fri 5/11/29 Start Up 62 Process Testing 4 wks Mon 5/14/29Fri 6/8/29 63 Develop Punchlist 2 wks Mon 6/11/29Fri 6/22/29 64 Project Closeout 4 wks Mon 6/25/29Fri 7/20/29

65 Final Completion 0 days Mon 7/23/29Mon 7/23/29 7/23 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 1.5: UpgradeP aagned 3Expansion Schedule Centreville WWTP ENR Upgrade and Expansion

Preliminary Engineering Report - DRAFT Centreville, MD 2 Background 2.1 Introduction The Town of Centreville, established in 1782, is the county seat of Queen Anne’s County and is the County's largest incorporated municipality with an estimated 2020 population of about 4,700 people. The Town, located on Corsica River is situated in the center of Queen Anne's County and is geographically positioned in the middle of

Maryland's Eastern Shore.

The Town of Centreville Board of Commissioners owns the Centreville WWTP located at 116 Johnstown Lane, Centreville, MD. The Centreville WWTP has a surface water discharge permit, state number 20-DP-0116 and NPDES discharge permit number MD0020834, and a groundwater discharge permit, state number 20-DP-3323 and NPDES discharge permit number MD3323R05. Each permit allows 0.542 MGD annual average flow to be

discharged. The Centreville WWTP has had an average daily flow of 0.40 MGD for the calendar years 2014 through 2022. The Town has experienced steady growth over the past several years and has been approached by multiple developers with plans to develop in the growth areas surrounding the current Town limits.

The Centreville WWTP was originally constructed in 1963, and major Biological Nutrient Removal (BNR) funded upgrades and expansion that was completed in 2005. The 2005 modifications included an upgrade of the facility to achieve BNR levels of treatment included total effluent nitrogen concentration of 5.5 mg-N/L, and total effluent phosphorus concentration of 1.0 mg-P/L. The nutrient removal process at the Centreville WWTP consists of a

two-tank SBR with chemical addition for phosphorous precipitation and cloth media filtration, as can be seen in Figure 2.1. The facility effluent total nitrogen and total phosphorus monthly average permit concentrations when discharging to surface waters are 5.5 and 1.0 mg/L, respectively.

Figure 2.1: Centreville WWTP SBR 2.2 Existing Facilities The facility provides preliminary treatment, with an activated sludge process for secondary biological nutrient removal, tertiary particulate filtration, followed by effluent disinfection with ultraviolet (UV) light, and final post aeration. Final effluent from the plant can be discharged to the Gravel Run stream December 1 to March 31, and groundwater application via spray irrigation from March 1 through December 15. A 20 million gallon (MG) working

volume effluent storage lagoon is located adjacent to the spray irrigation fields. Sludge generated in the treatment process is stored in an aerated storage tank and applied and dried in reed beds. Periodically, the reed beds are removed an disposed of by land application.

Figure 2.2 provides the existing process flow diagram (PFD).

Page 13 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 2.3 provides an overview of the existing treatment process facilities at the Centreville WWTP.

Filter and Blower Building, including UV Disinfection Post Equalization SBR Tank 2 SBR Tank 1 Tank Effluent Pump Station Sludge Holding Tank Influent Screening Figure 2.3: Existing Treatment Facilities (Credit: Google Earth) Figure 2.4 provides an overview of the existing sludge reed drying beds, chlorine contact tank, Laboratory and Administration Building, and the influent screening.

Page 15 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Laboratory and Chlorine Contact Tank Influent Admin Building Screening Sludge Reed Drying Beds Figure 2.4: Further Existing Facilities (Credit: Google Earth) 2.3 Objective The overall objective for the project is to expand the liquid and solids treatment and treated effluent disposal capacity to both meet the needs of the anticipated growth within the service area, as well as meet ENR level

treatment and continue compliance with the NPDES discharge permit(s). In concert with the upgrade, the supporting facilities, including the laboratory, office space, and backup power system, will be upgraded. An on-site non-potable water system will be added to allow for the use of treated effluent for a variety of applications, which will increase the efficiency of the plant.

2.3.1 Treatment Quality Goals Under the plant’s current NPDES discharge permits, treated effluent is disposed into Gravel Run, a tributary to Corsica River, during the period between December 1 through March 31. No stream discharge is permitted from April 1 through November 30 and during this period effluent up to the permitted capacity is disposed of by offsite spray irrigation to ground waters through a separate permit (both the stream permit and the ground water permit

are included in Appendix B).

Page 16 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD With the proposed treatment capacity expansion, the effluent disposal capacity will need to be expanded as well and the Town envisions a combination of spray irrigation and year-round stream discharge. However, year-round stream discharge will require a relocation of the current Gravel Run outfall to a new outfall location further

downstream and directly into Corsica River as identified in MDE’s Nutrient TMDL for Corsica River. As such, with the capacity expansion, the Town intends to replace the current BNR treatment process with enhanced nutrient removal (ENR) technology to meet TN and TP effluent levels of 3.0 mg/L and 0.3 mg/L, respectively.

Page 17 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 3 Project Planning 3.1 Cost and Effectiveness Analysis The development of viable treatment alternatives considers and weights monetary and non-monetary factors to deliver a project that meets the treatment objectives, is resilient, preserves natural resources, and is cost effective. The Town of Centreville WWTP ENR Upgrade and Expansion project is similar to other WWTP upgrade

projects in Maryland that have implemented enhanced nutrient removal, and the alternatives propose to utilize equipment and treatment processes that have been proven successful and cost effective elsewhere.

Components that do preserve natural resources and are cost effective are incorporated into the project wherever practical. Examples include the inclusion of a treated effluent supplied non-potable water system for onsite process water uses in place of potable water, and the use of slow speed sludge dewatering equipment that draws less power than high rotational speed centrifuges.

Throughout the design process, there will be opportunities to select equipment that provides energy and water efficiency. Examples include:

1.) Selecting influent screens that require less wash water, 2.) Specifying the latest generation of UV light disinfection equipment, 3.) Utilizing high efficiency process blowers, 4.) Incorporating process controls and instrumentation that automatically maintains the treatment process and reduces energy use.

The alternatives selected will all meet the treatment goals. The non-monetary evaluation incorporates components for considering the following:

1.) Reuse of existing assets, 2.) Compatibility with future upgrades to meet ever more stringent regulations, 3.) Water reuse and, 4.) Long term project maintainability.

The Town is interested in water reuse, including treated effluent water use onsite for processes where currently potable water is used and non-potable water can be used instead, consideration for future Class III or IV reclaimed water use off-site, and planning for potential future direct or indirect potable water reuse.

3.2 Environmental Resources A desktop analysis was conducted to identify environmental resources within the project study area. These resources include the United States Fish and Wildlife Service (USFWS) National Wetland Inventory, the Maryland Department of Natural Resources (MDNR) Wetlands, Maryland Department of the Environment (MDE) Wetlands of State Special Concern (WSSC), Federal Emergency Management Agency (FEMA) Floodplain data, MDE Tier

II (High Quality) Waters, Chesapeake Bay Critical Areas (CBCA), Forest Interior Dwelling Species (FIDS) Habitat, MDNR Sensitive Species Project Review Areas (SSPRA), and Maryland Bird Conservation Partnership’s bald eagle nest locations.

In addition to the desktop analysis, Coastal Resources, Inc. (CRI) conducted a site visit in July – August 2023 to conduct a waters of the U.S. (including wetlands) delineation and to map forest resources and other habitats.

Wetlands were assessed in accordance with the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Atlantic Gulf and Coastal Plain Region, Version 2.0 (USACE 2010). All identified waters of the U.S., including wetlands, were classified according to A Classification of Wetland and Deep-Water Habitats in the United States (USFWS 1979).

Page 18 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Terrestrial habitats within the study area were broadly assessed to document their general physical condition and quality. Forest stands were characterized by successional stage, dominant and codominant species, size class, common understory and herbaceous species, percent canopy closure, prevalence of downed woody debris,

presence of invasive species, and basal area. CRI also identified specimen trees with a 30-inch diameter at breast height (DBH) or higher, or that have a diameter which is 75% of the State Champion of that species, including the location, species, size, and health of each specimen tree. A summary of the results of the site visit is included below.

3.2.1 Desktop Analysis Based on the desktop analysis, several environmental resources are present within the study area, including CBCA, FIDS habitat, MDE Tier II (High Quality) Waters, 100-year floodplains, and wetlands mapped by the NWI and DNR. No WSSC, SPRA, or bald eagle nests are mapped within the project study area. Mapped resources are depicted in Figure 3.1. The CBCA is located throughout the project study area and classified as an Intensely

Developed Area (IDA). FIDS habitats are mapped in the forest areas surrounding the WWTP property. The entire project study area is within the Gravel Run 1 Tier II (High Quality) catchment. A 100-year floodplain is present on the northern portion of the study area associated with Gravel Run. A palustrine emergent (PEM) wetland was mapped by the NWI on the northern portion of the project area. In addition to NWI, DNR mapped palustrine

forested (PFO) and estuarine intertidal emergent (E2EM) wetlands in the forested areas just north of the WWTP site.

3.2.2 Waters of the U.S. (Including Wetlands) Delineation The results of the wetland delineation indicate that there are three vegetated wetlands and two perennial streams within the project study area (see Figure 3.1). Wetland 1 (WL1) is a small, isolated PEM wetland located in drainage swale adjacent to the WWTP entrance road. Wetland 2 is a PFO floodplain depressions on the eastern portion of the project study area associated with Gravel Run (WC1). Wetland 3 is also a PFO floodplain

depression associated with an and an unnamed tributary to Gravel Run (WC2). Watercourse 1 (WC1) is Gravel Run, a lower perennial stream that flows northwest along the eastern boundary of the project study area.

Watercourse 2 (WC2) is an unnamed lower perennial tributary to Gravel Run on the north-central portion of the project area that receives water from the treatment plant discharge.

3.2.3 Terrestrial Habitat Terrestrial habitats include three forest stands on the northern portion of the study area (see Figure 3.1). Stand 1 consists of an early-mid succession ash-leaf maple (Acer negundo) – black locust (Robinia pseudoacacia) forest with abundant downed woody debris, high invasive plant cover, and fair structure. One specimen tree was identified in Stand 1. This stand was considered poor due to high invasive cover, fair structure, and an abundance

of trash/rubble. Stand 2 consists of an early succession black willow (Salix nigra) – American elm (Ulmus americana) wetland forest. Downed woody debris was abundant in this stand, with moderate invasive plant cover, and poor structure. No specimen trees were identified in Stand 2. This stand was considered fair due to moderate invasive cover, presence of trash, and poor structure. Stand 3 consists of a mid-late succession tulip

tree (Liriodendron tulipifera) – silver maple (A. saccharinum) forest with abundant downed woody debris and a total of 12 specimen trees. Due to the high invasive plant cover, abundance of dead/dying trees, and presence of trash/rubble, this stand was considered poor.

3.2.4 Coast Smart Climate Ready Action Boundary (CS-CRAB) To determine the potential impact of sea level rise on the project area, the limits of the Coast Smart Climate Ready Action Boundary (CRAB) were reviewed (Source: https://mdfloodmaps.net/CRAB/). The CRAB represents the county-wide depth of flooding given a 3 foot (vertical and associated horizontal) increase in water surface Page 19 Centreville WWTP ENR Upgrade and Expansion

Preliminary Engineering Report - DRAFT Centreville, MD elevation above the current effective 100-year floodplain. The CRAB boundaries include areas that may be inundated from 0 to 1 foot, 1 to 2 feet, and greater than 2 feet. These layers are shown on Figure 3.1. Based on the CRAB, inundation of 0 to 1 foot, 1 to 2 feet, and greater than 2 feet were identified on the northern and eastern portion of the study area.

Page 20

A

D

L

WC1 -

Gravel Run

ID

A

WL3

002 009 Stand 3 005 003 008

013 WL1

WC2 007 006

004 010 Stand 2

WL2

ID

L A

D

A Stand 1 011 001 012 Jo St h n

L D

A

P o w ell sto w n L a ± Delineated Forest & Trees Coast Smart CRAB* NWI Wetland Centreville Wastewater Treatment Plant Expansion Project Specimen Tree 0 to 1 Foot CRAB Inundated DNR Wetland Water 1 to 2 Foot CRAB Inundated Chesapeake Bay Critical Area Forest Stand Treatment Figure 3.1: Environmental Resources Map Greater than 2 Foot CRAB Inundated Forest Interior Dwelling Species Delineated Wetlands & Waters Facility

Effective FEMA Floodplain Tier II Catchments 2021 Queen Anne's County, Maryland 25' Wetland Buffer 0 50 100 100 Year Floodplain (1% Chance) Assimilative Capacity Remaining May 2024 Palustrine Emergent Wetland No Assimilative Capacity Remaining feet Palustrine Forested Wetland 1 inch = 100 feet Perennial Stream *Coast Smart Climate Ready Action Boundary (CRAB) represents the county-wide depth of flooding given

Map Center, NAD83 a 3 foot (vertical and associated horizontal) increase in water surface elevation above the current Study Area effective 100-year floodplain. 39.0486°, -76.0644° 1 inch = 2 miles Source: Large-scale map: Maryland iMAP, DoIT. Imagery flown in 2022 (Eastern Shore) and 2020 (Western Shore). Received May 2024. Small-scale map: Esri, HERE, Garmin, FAO, NOAA, USGS, OpenStreetMap contributors, and the GIS user community. Received May 2024.

Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 3.3 Location The project is located on 116 Johnstown Lane, within the town limits of the Town of Centreville which is the county seat of Queen Anne’s County on the eastern shore of Maryland. The project will be on parcels currently owned by the Town Council of Centreville.

3.4 Population Trends Population in the Town has grown from 2,018 in the 1980 census to 4,949 in the 2020 census, see Table 3.1 and are expected to grow for at least several more years.

Table 3.1: Centreville Population Data Year 1980 1990 2000 2010 2020 Population1 2,018 2,097 1,970 4,285 4,949 Growth Rate 8.9% 3.9% -6.1% 117.5% 1.5% https://www.census.gov/programs-surveys/popest/technical-documentation/research/evaluation-estimates/2020-evaluation-estimates/2010scities-and-towns-total.html The data from Table 3.1 is also depicted in Figure 3.2.

6000 5000 4000 3000 2000 1000 0 1980 1990 2000 2010 2020 Figure 3.2: Centreville Population According to the Queen Anne’s County 2011 Comprehensive Water and Sewerage Plan:

“The Growth Areas generally include parcels of land contiguous to the east and west sides of the current Town boundaries. It is anticipated that growth pressures will occur, for the most part, on the Route 301 side of Centreville, due to the multiple road connections. Present growth patterns in and near the Town support this premise. The Town anticipates a phased approach to annexation.” The Town of Centreville Community Plan, 2009, estimated total future wastewater demand of 1.62 MGD.

Page 22 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 4 Existing Performance, Facilities, and Conditions 4.1 Location Map The Centreville WWTP is located within a residential area of the town. Figure 4.1 provides a location map to show the relative distance between Centreville WWTP and the irrigation spray fields.

Spray Irrigation Fields Wastewater Treatment Facility Figure 4.1: Location Map (Credit: Google Earth) 4.2 History The original portions of the Town’s sewer collection system were installed in 1934. A primary wastewater treatment facility was constructed in the 1960’s. A major Biological Nutrient Removal (BNR) upgrade was completed in 2005 that installed influent screening, a two (2) tank SBR, cloth media particulate tertiary filters, UV

light disinfection, effluent pumping, treated effluent storage lagoons, spray irrigation fields, and reed drying beds.

The treatment was designed to provide treatment for 0.542 MGD of annual average flow with an effluent total nitrogen of 5.5 mg/L, and effluent total phosphourus of 1.0 mg/L.

The receiving stream, Gravel Run, is a tributary of the Corsica River. At the time of the planning and design of the 2005 BNR upgrade and expansion, the total maximum daily loads for the Corsica River were being developed. To accommodate the planned flows, the Town decided to forgo year-round discharge to Gravel Run and developed a spray irrigation disposal system to provide 0.542 MGD of disposal capacity. Discharge to Gravel Run was

restricted to cold weather months.

Page 23 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 4.3 Financial Status As described in Section 3.4, the Town has been experiencing growth within the existing water and sewer service areas. As the largest town in Queen Anne’s County, it’s central location on the eastern shore, and its designation as a Smart Growth area, the population is expected to continue to grow significantly for many years. The Queen

Anne’s County Comprehensive Water and Sewer Plan indicates future build out flows will reach 1.75 MGD of sanitary flow.

The Town has invested significant funds into upgrading its water distribution and sanitary collection systems to improve their integrity and position them for future flows.

The Town’s recent and budgeted water and sewer income and expenses are summarized in Tables 4.1 and 4.2.

Table 4.1: Recent Water and Sewer Income and Expenses Water Sewer Fiscal Year (FY) Income Expenses Income Expenses

FY20 $844,402 $1,115,148 $891,258 $1,156,565

FY21 $1,029,299 $1,122,767 $1,135,004 $1,073,320

FY22 $1,343,266 $1,298,048 $1,366,296 $1,206,366

FY23 (Through $604,136 $543,029 $591,252 $850,908 3/28/2023) Table 4.2: Budgeted Water and Sewer Income and Expenses Water Sewer Fiscal Year (FY) Income Expenses Income Expenses

FY24 $1,414,928 $1,616,603 $1,531,427 $1,510,483

FY25 $1,485,675 $1,697,433 $1,607,998 $1,586,007

FY26 $1,574,816 $1,782,305 $1,704,478 $1,665,307

FY27 $1,685,053 $1,871,420 $1,826,791 $1,781,878

FY28 $1,819,857 $1,964,991 $1,972,694 $1,870,972

The existing debt service held by the Town for the water and wastewater systems are summarized in Table 4.3.

Table 4.3: Existing Debt Service Area Existing Debt (as of March 2023) Water $5,075,189 Sewer $4,960,400 Page 24 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 4.4 Current Influent Conditions Influent conditions are not measured on a regular basis at the Centreville WWTP. Operators are able to gather composite samples of the influent when required. Composite influent sampling data from September/October

2017 and March 2023 was provided by the Town of Centreville for evaluations in this PER. Table 4.4 lists the existing estimated average and maximum monthly influent conditions, based on the available sampling data.

Appendix C

includes all data from influent sampling.

Table 4.4: Existing Influent Conditions at Centreville WWTP Biochemical Volatile Total Total Kjeldahl Total Wastewater Oxygen Flow Suspended Suspended Nitrogen Phosphorus Condition Temperature Demand Solids (VSS) Solids (TSS) (TKN) (TP)

(BOD)

(MGD) (Deg C) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) Average 1.0 20 130 116 145 35 8 Maximum 1.2 12 156 139 174 42 8 Monthly 4.5 Existing Plant Performance Operations collects samples for analysis at the plant effluent for annual quality reporting. The effluent quality data from the monthly operating reports (MORs) that is relevant to the ENR upgrades was reviewed. The annual average, maximum monthly, and peak daily effluent flows from both stream discharge and spray discharge are

summarized in Table 4.5.

Table 4.5: Centreville WWTP Stream and Spray Effluent Flows Stream Effluent Flow (MGD) Spray Effluent Flow (MGD) Maximum Maximum Annual Annual Year Monthly Peak Day Flow Monthly Peak Day Flow Average Average Average Average 2014 0.34 0.36 0.54 0.25 0.57 2.09 2015 0.38 0.44 0.90 0.25 0.62 2.44 2016 0.45 0.47 0.60 0.25 0.51 1.88 2017 0.38 0.39 0.71 0.21 0.56 2.17 2018 0.49 0.66 0.93 0.36 0.64 2.05 2019 0.59 0.66 0.87 0.37 0.66 1.97

2020 0.51 0.71 0.93 0.37 0.52 1.72 2021 0.59 0.70 1.02 0.45 0.57 0.68 2022 0.46 0.49 0.68 0.39 0.42 0.69 The annual average and maximum monthly average for calendar years 2014 through 2022 for the total effluent flow, biochemical oxygen demand (BOD) concentration, total suspended solids (TSS) concentration, total kjeldahl nitrogen (TKN) concentration, ammonia (NH ) concentration, nitrate + nitrite (NO + NO ) concentration, total

3 2 3 nitrogen (TN) concentration, total phosphorus (TP) concentration, and E. coli concentration are included in Tables 4.6 through 4.9. Tables 4.6 and 4.7 summarize the effluent quality of the stream discharge, which occurs during the winter months (December to March). Tables 4.8 and 4.9 summarize the effluent quality of the spray discharge, which occurs throughout the warmer months of the year (April to November). Appendix C includes all

available weekly average data for these categories.

Page 25 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 4.6: Centreville WWTP Stream Effluent BOD, TSS, TKN, and Ammonia Concentrations Effluent Ammonia Effluent BOD (mg/L) Effluent TSS (mg/L) Effluent TKN (mg/L) (mg/L) Maximum Maximum Maximum Maximum Annual Annual Annual Annual Year Monthly Monthly Monthly Monthly Average Average Average Average

Average Average Average Average 2014 4.19 5.75 3.53 4.38 1.20 1.93 0.50 1.07 2015 3.15 4.05 1.31 2.19 0.71 1.07 0.14 0.17 2016 2.15 2.62 1.21 1.38 0.45 0.55 0.17 0.21 2017 2.50 3.03 1.77 2.60 0.85 0.97 0.20 0.32 2018 3.44 4.21 2.80 3.83 1.13 1.49 0.37 0.62 2019 2.02 2.78 0.99 1.13 0.72 0.88 0.28 0.35 2020 1.87 2.43 0.79 1.00 1.34 3.38 0.41 0.52 2021 1.63 1.87 2.84 7.83 1.86 2.07 0.54 0.90 2022 2.40 3.89 2.08 3.00 1.74 2.21 0.63 0.81

Overall 2.76 1.77 0.91 0.29 Average Table 4.7: Centreville WWTP Stream Effluent Total NO2 + NO3, TN, TP, and E. Coli Concentrations Effluent Total NO2 + Effluent TN (mg/L) Effluent TP (mg/L) Effluent E. Coli NO3 (mg/L) (MPN/100 mL) Maximum Maximum Maximum Maximum Annual Annual Annual Annual Year Monthly Monthly Monthly Monthly Average Average Average Average Average Average Average Average 2014 2.09 2.60 3.29 4.20 0.25 0.75 1.28 1.90

2015 1.89 2.24 2.61 2.88 0.18 0.26 4.52 12.4 2016 2.32 2.98 2.76 3.39 0.21 0.25 4.80 41.2 2017 1.46 1.70 2.32 2.67 0.46 0.64 1.22 9.98 2018 1.72 2.06 2.91 3.38 0.45 0.78 20.6 42.9 2019 1.83 2.65 2.55 3.39 0.66 1.12 31.3 91.6 2020 1.21 1.48 2.55 4.87 0.88 1.05 118 185 2021 1.63 2.54 3.15 3.55 0.68 0.95 461 1148 2022 1.39 2.42 2.82 3.31 1.16 2.14 2.40 538 Overall 1.79 2.71 0.44 25.93 Average Table 4.8: Centreville WWTP Spray Effluent BOD, TSS, TKN, and Ammonia Concentrations

Effluent Ammonia Effluent BOD (mg/L) Effluent TSS (mg/L) Effluent TKN (mg/L) (mg/L) Maximum Maximum Maximum Maximum Annual Annual Annual Annual Year Monthly Monthly Monthly Monthly Average Average Average Average Average Average Average Average 2014 2.72 3.88 4.22 4.50 0.82 1.09 0.22 0.27 2015 3.87 6.26 3.03 6.08 0.85 1.20 0.18 0.27 2016 3.44 5.22 1.57 3.22 0.81 1.36 0.23 0.64 2017 3.17 4.08 1.52 3.00 0.90 1.30 0.16 0.30

2018 2.76 4.63 1.17 1.63 1.09 1.77 0.19 0.75 2019 1.27 1.64 0.67 0.94 0.98 1.14 0.18 0.28 2020 1.76 2.69 0.86 1.44 1.00 1.95 0.40 1.03 2021 2.41 3.70 1.89 3.00 1.96 3.48 0.57 2.22 2022 2.06 2.75 2.35 4.50 1.37 1.67 0.37 0.60 Overall 2.71 1.86 0.92 0.22 Average Page 26 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 4.9: Centreville WWTP Spray Effluent Total NO2 + NO3, TN, TP, and E. Coli Concentrations

Effluent Total NO2 + Effluent TN (mg/L) Effluent TP (mg/L) Effluent E. Coli NO3 (mg/L) (MPN/100 mL) Maximum Maximum Maximum Annual Annual Annual Annual Annual Year Monthly Monthly Monthly Average Average Average Average Average Average Average Average 2014 2.28 2.28 3.10 3.46 0.79 1.18 3.54 11.5 2015 1.62 1.62 2.31 2.71 1.13 1.86 2.72 6.67 2016 1.58 1.58 2.39 2.88 2.02 3.15 2.57 6.37 2017 1.42 1.42 2.30 2.96 1.82 2.54 5.99 14.6

2018 1.58 1.58 2.63 3.17 1.68 2.56 3.69 7.59 2019 1.58 1.58 2.56 2.93 1.67 2.54 5.22 23.3 2020 1.50 1.50 2.46 3.16 1.84 2.63 7.64 30.2 2021 2.03 2.03 3.77 5.09 1.58 2.41 236.15 908 2022 1.83 3.47 2.71 4.54 2.43 3.64 234.03 1223 Overall 1.65 2.54 1.57 4.48 Average Since January 2014, Centreville WWTP has had an average stream effluent total flow of 0.45 MGD and an average spray effluent flow of 0.29 MGD. Figures 4.2 and 4.3 show the monthly average stream and spray

effluent flows from January 2014 to December 2022.

Monthly Average Stream Effluent Flow 0.800 0.700 0.600

) D 0.500

G

M

0.400 ( w o 0.300 lF 0.200 0.100 0.000 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O Month Figure 4.2: Stream Effluent Total Flow Page 27 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent Flow 0.700 0.600 0.500 )

D

G 0.400

M

( w 0.300 o lF 0.200 0.100 0.000 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J

- v

o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.3: Spray Effluent Total Flow Figures 4.4 and 4.5 show the monthly averages of effluent BOD concentrations from January 2014 to December 2022. Since January 2014, the average stream effluent BOD concentration is 2.76 mg/L, and the average spray effluent BOD concentration is 2.71 mg/L.

Monthly Average Stream Effluent BOD 7.00 6.00 )

L

/ g m 5.00 ( n o it 4.00 a r t n e 3.00 c n o

C 2.00

D

O

B 1.00

0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O Month Figure 4.4: Stream Effluent BOD Concentration Page 28 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent BOD 7.00 6.00 )

L

/ g m 5.00 ( n o it 4.00 a r t n e 3.00 c n o

C 2.00

D

O

B

1.00 0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.5: Spray Effluent BOD Concentration Since January 2014, the average stream and spray effluent TSS concentrations are 1.77 mg/L and 1.86 mg/L, respectively. Figures 4.6 and 4.7 show the monthly averages of effluent TSS concentrations from January 2014 to December 2022.

Monthly Average Stream Effluent TSS 9.00 8.00 )

L / 7.00

g m ( 6.00 n o it 5.00 a r t n 4.00 e c n 3.00 o

C

S 2.00

S

T

1.00 0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O Month Figure 4.6: Stream Effluent TSS Concentration Page 29 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent TSS 7.00 6.00 )

L

/ g m 5.00 ( n o 4.00 it a r t n 3.00 e c n o

C 2.00

S

S

T

1.00 0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.7: Spray Effluent TSS Concentration Figures 4.8 and 4.9 show the monthly average stream and spray effluent TKN since January 2014. From January 2014 to December 2022, the average stream effluent TKN is 0.91 mg/L, and the average spray effluent TKN is 0.92 mg/L.

Monthly Average Stream Effluent TKN 2.50

) L 2.00

/ g m ( n o 1.50 it a r t n e 1.00 c n o

C

N

K 0.50

T

0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D Month Figure 4.8: Stream Effluent TKN Concentration Page 30 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent TKN 4.00 3.50 )

L

/ g 3.00 m ( n 2.50 o it a r 2.00 t n e c 1.50 n o

C

N 1.00

K

T

0.50 0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.9: Spray Effluent TKN Concentration Figures 4.10 and 4.11 show the monthly average stream and spray effluent ammonia since January 2014. Since January 2014, the average stream and spray effluent ammonia concentrations are 0.29 mg/L and 0.22 mg/L, respectively.

Monthly Average Stream Effluent Ammonia 1.20 )

L

/ g 1.00 m ( n o 0.80 it a r t n e 0.60 c n o

C

a 0.40 in o m 0.20 m

A

0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2

- n

a J

- n

u J

- v

o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D Month Figure 4.10: Stream Effluent Ammonia Concentration Page 31 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent Ammonia 2.50 )

L

/ g m 2.00 ( n o it a 1.50 r t n e c n o 1.00

C

a in o 0.50 m m

A

0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.11: Spray Effluent Ammonia Concentration Figures 4.12 and 4.13 show the monthly average nitrate plus nitrate (NO + NO ) concentrations in the stream 3 2 and spray effluent from January 2014 to December 2022. On average, the NO + NO concentrations in the 3 2 stream and spray effluent have been 1.79 mg/L and 1.65 mg/L, respectively, since January 2014.

Monthly Average Stream Effluent NO + NO 3 2 3.50 )

L

/ g 3.00 m ( n 2.50 o it a r t 2.00 n e c n 1.50 o

C

O

21.00

N

+ 30.50

O

N

0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D Month Figure 4.12: Stream Effluent NO + NO Concentration 3 2 Page 32 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent NO + NO 3 2 4.00 )

L 3.50

/ g m ( 3.00 n o it 2.50 a r t n e 2.00 c n o

C 1.50

2

O

N 1.00

+ 3

O 0.50

N

0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.13: Spray Effluent NO + NO Concentration 3 2 The monthly average TN concentrations in the stream and spray effluent from January 2014 to December 2022 are shown in Figures 4.14 and 4.15. The average TN concentration in the stream effluent is 2.71 mg/L, and the average total nitrogen concentration in the spray effluent is 2.54 mg/L.

Monthly Average Stream Effluent Total Nitrogen

(TN)

6.00 )

L

/ g 5.00 m ( n o 4.00 it a r t n 3.00 e c n o 2.00

C

N

la 1.00 t o

T

0.00 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O Month Figure 4.14: Stream Effluent Total Nitrogen Concentration Page 33 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent Total Nitrogen (TN) 6.00 )

L

/ 5.00 g m ( n 4.00 o it a r t n 3.00 e c n o 2.00

C

N

la t 1.00 o

T

0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.15: Spray Effluent Total Nitrogen Concentration Figures 4.16 and 4.17 show the monthly average TP concentrations in the stream and spray effluent from January 2014 to December 2022. The overall average TP concentration in the stream effluent is 0.44 mg/L, and the overall average TP concentration in the spray effluent is 1.57 mg/L. The monthly average TP concentrations have increased over the recent years, which is likely due to the increased flow through the WWTP.

Monthly Average Stream Effluent Total Phosphorus (TP) 2.50 )

L

/ g 2.00 m ( n o it 1.50 a r t n e c n 1.00 o

C

P

la 0.50 t o

T

0.00 4 4 4 5 5 5 6 6 6 7 7 7 8 8 8 9 9 9 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2

- n - y - p - n - y - p - n - y - p - n - y - p - n - y - p - n - y - p - n - y - p - n - y - p

a a e a a e a a e a a e a a e a a e a a e a a e

J M S J M S J M S J M S J M S J M S J M S J M S

Month Figure 4.16: Stream Effluent Total Phosphorus Concentration Page 34 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent Total Phosphorus

(TP)

4.00 ) 3.50

L

/ g m 3.00 ( n o 2.50 it a r t n 2.00 e c n 1.50 o

C

P 1.00

la t o T 0.50 0.00 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.17: Spray Effluent Total Phosphorus Concentration Since January 2014, Centreville WWTP has had an average stream effluent E. coli concentration of 25.9 MPN/100 mL and an average spray effluent E. coli concentration of 4.48 MPN/100 mL. Figure 4.18 and Figure 4.19 show the monthly average stream and spray effluent E. coli concentrations from January 2014 to December 2022. E. coli concentrations have increased in the effluent in recent years due to the WWTP operating closer to

its design capacity.

Monthly Average Stream Effluent E. Coli 1400 )

L

m 1200 0 0 1 / 1000

N

P

M 800

( n o 600 it a r t 400 n e c n 200 o

C

ilo 0

C 4 4 4 5 5 6 6 6 7 7 8 8 9 9 9 0 0 1 1 1

.E 1

- n

a J 1

- n

u J 1 -v o N 1

- r

p A 1

- p

e S 1

- b

e F 1

- lu

J

1

- c

e D 1

- y

a M 1

- t

c O 1

- r

a M 1

- g

u A 1

- n

a J 1

- n

u J 1 -v o N 2

- r

p A 2

- p

e S 2

- b

e F 2

- lu

J

2

- c

e D Month Figure 4.18: Stream Effluent Geomean E. Coli Concentration Page 35 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Monthly Average Spray Effluent E. Coli 1400 )

L

m 1200 0 0 1

/ N 1000

P

M

( n 800 o it a r 600 t n e c n 400 o

C

ilo 200

C

.E

0 4 4 5 5 5 6 6 7 7 8 8 8 9 9 0 0 0 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A

- n

a J

- n

u J -v o N

- r

p A

- p

e S

- b

e F

- lu

J

- c

e D

- y

a M

- t

c O

- r

a M

- g

u A Month Figure 4.19: Spray Effluent Geomean E. Coli Concentration 4.6 Condition of Existing Facilities The Centreville WWTP is generally operating as intended without excessive maintenance and repair costs. The WWTP was most recently upgraded in 2003; therefore, most of the equipment is approximately 20 years old.

Most mechanical equipment has a planned 20-year expected life.

4.6.1 Treatment Process Overview The wastewater enters the WWTP via mostly force main, and some gravity pipelines, into a manhole, and then flows by gravity through a screening facility. The screened flow continues to the SBR tanks. Flow is directed into one (1) of the two (2) SBR tanks through two automated valves controlled by the SBR Control Panel.

The operation of an SBR is based on a fill-and-draw principle, which consists of five steps: fill, react, settle, decant, and idle. These steps can be altered for different operational applications and the general sequence is shown in Figure 4.20.

Page 36 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 4.20: Sequencing Batch Reactor Sequence of Operation (Source: Aqua-Aerobic Systems, Inc.) Fill During the fill phase, the basin receives influent wastewater. Mixing and aeration can be varied during the fill phase to create the different environments for the biomass analogous to the conditions in a traditional

activated sludge basin, anaerobic, oxic, and anoxic.

React During this phase, no wastewater enters the basin, and the mechanical mixing and aeration units are on.

Most of the carbonaceous BOD removal occurs in the react phase. Further nitrification occurs by allowing the mixing and aeration to continue. Because there are no additional volume and organic loadings, the rate of organic removal increases dramatically.

Settle During this phase, activated sludge can settle under quiescent conditions — no flow enters the basin and no aeration and mixing takes place. The activated sludge tends to settle as a flocculent mass, forming a distinctive interface with the clear supernatant. This phase is a critical part of the cycle, because if the solids do not settle rapidly, some sludge can be drawn off during the subsequent decant phase and

thereby degrade effluent quality.

Decant During this phase, a decanter is used to remove the clear supernatant effluent. The floating decanter maintains the inlet orifice slightly below the water surface to minimize the removal of solids in the effluent removed during the decant phase, an example is shown in Figure 4.21. Floating decanters offer the operator flexibility to vary fill and draw volumes.

Idle This step occurs between the decant and the fill phases. The time varies, based on the influent flow rate and the operating strategy. During this phase, a small amount of activated sludge at the bottom of the SBR basin is pumped out.

Page 37 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 4.21: SBR Tank w/Surface Mixer/Aerator and Decant Device (Credit: Aqua-Aerobic Systems, Inc.) Decant from the SBR flows into a post equalization tank, and waste sludge is pumped into an aerated sludge digestion tank. Submersible pumps send the SBR decant to a cloth media filter. The filtered effluent flows by

gravity through a UV light disinfection channel, and then into the wet well of the Effluent Pump Station. Flow is either pumped to the effluent storage lagoon or flows by gravity to the chlorine contact tank.

4.6.2 Process/Equipment Assessment 4.6.2.1 Influent Screening The influent screening is rotating drum screen manufactured by Lakeside. The screen is reported to effectively remove solids and is operating as intended. Operations also reported that this model of screen is no longer manufactured by Lakeside, and the cost of spare parts have increased significantly, as has the lead time to obtain parts. It is recommended to replace the screen, retrofitting the existing concrete channel as needed.

4.6.2.2 Sequencing Batch Reactor The SBR provides treatment of the influent wastewater. BOD is removed and the influent TKN is nitrified to ammonia. The SBR is also able to partially denitrify the ammonia to nitrogen gas, to provide BNR levels of treatment, typically less than 5 mg/L of TN in the treatment plant effluent. Table 4.10 provides the physical arrangement of the SBR’s two (2) rectangular tanks.

Page 38 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 4.10: Existing SBR Tanks Parameter Value Units Length, each 70.5 Ft Width, each 53.2 Ft Volume at Min. Side 0.402 Million Gallons Water Depth, each Volume at Avg. Side 0.464 Million Gallons Water Depth, each Volume at Max. Side 0.589 Million Gallons Water Depth, each The SBR process equipment in each of the two (2) SBR basins includes:

• One (1) Influent Actuated Valve

• One (1) Surface Mixer

• Five (5) Removable Fine Bubble Aeration Diffuser assemblies

• One (1) Decant Mechanism

• One (1) Submersible Sludge Transfer Pump

The equipment is in good shape and is operating as intended. Although the equipment is nearing its expected life, it may have additional years of service left, in the range of 3-5 years with close attention to following factory advised maintenance and rebuilds.

The air for the liquid treatment process, and the post equalization tank, is supplied by three (3) 50 Horsepower (HP) blowers located in the Filter and Blower Building. Each blower has the design operating point of 525 SCFM, at a pressure of 10.7 PSIG. The existing blowers are operating as intended and appear to have many years of service life left with close attention and following the factory advised maintenance and rebuilds.

4.6.2.3 Post Equalization Tank The decant from the SBR flows into the post equalization tank for aeration and to reduce the fluctuations in the flow to the downstream processes. A summary of the physical arrangement of the post equalization tank is in Table 4.11.

Table 4.11: Existing Post Equalization Tank Parameter Value Units Length 52.9 Ft Width 36.7 Ft Min. Basin Volume 0.021 Million Gallons Max. Basin Volume 0.146 Million Gallons Working Volume 0.125 Million Gallons Page 39 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Equipment in the post equalization tank includes:

• Fine Bubble Diffuser Assemblies

• Two (2) Submersible Centrifugal Filtration Feed Pumps

The equipment is in good shape and is operating as intended. Although the equipment is nearing its expected life, it appears to have many additional years of service left with close attention to following the factory advised maintenance and rebuilds.

4.6.2.4 Sludge Holding Tank Sludge wasted from the SBR is pumped into the sludge holding tank for stabilization (i.e., reduction of volatile solids). The sludge holding tank physical layout information is in Table 4.12.

Table 4.12: Existing Sludge Holding Tank Parameter Value Units Length 52.9 Ft Width 32.3 Ft Min. Basin Volume 0.138 Million Gallons Max. Basin Volume 0.197 Million Gallons Equipment in the sludge holding tank includes:

• One (1) 10 HP surface mixer

• Two (2) 30 HP floating aerators

• Supernate Pump

• Sludge Transfer Pump

The equipment is in good shape and is operating as intended. Although the equipment is nearing its expected life, it may have many additional years of service left with close attention and following factory advised maintenance and rebuilds.

4.6.2.5 Cloth Media Filtration Treated wastewater from the post equalization tank is pumped to a cloth media filter for the removal of suspended solids. The media filter is an AquaDisk unit manufactured by Aqua Aerobic Systems Inc., the same manufacturer as the SBR. The filter is a packaged unit complete with controls and backwashing and solids wasting system, see Figure 4.22 which shows the main components of a disk filter.

Page 40 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 4.22: Cloth Media Filter Components (Credit: Aqua-Aerobic Systems, Inc.) The media filter has been reported by operations to experience excessive head loss during typical wet weather flows, causing bypassing of the filter, degrading the effluent quality. The filter has produced excellent quality

effluent during dry weather flows.

4.6.2.6 UV Light Disinfection The filtered wastewater flows by gravity through a UV light disinfection channel. A total of twenty-four (24) low pressure high output ultraviolet lamps. The intense UV light inactivates microorganisms by destroying nucleic acids and disrupting their DNA. A typical unit can be seen in Figure 4.23.

Figure 4.23: UV Disinfection Unit Isometric View (Credit: Enaqua) The UV unit design parameters are included in Table 4.13.

Table 4.13: Existing UV Disinfection Parameter Value Units Peak Hour Flow 0.75 MGD Quantity of UV Reactors 1 - Number of Total Lamps 24 - UV Dose (Calculated) > 40 mJ/cm2 MPN/100 mL E.

Effluent Quality < 84 Coli Page 41 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD The UV disinfection system was installed in 2016 and is operating as intended. Additional units will be needed for the expansion to 1.0 MGD AAF. Additionally, Class III and Class IV Water Reuse will require more stringent Fecal Coliform effluent quality.

4.6.2.7 Effluent Pump Station Design information on the two (2) Goulds 20 HP effluent pumps was not available, but operations reports that the pump station can get overwhelmed during wet weather flows. The pumps were installed as part of the 2003 upgrade.

4.6.2.8 Chlorine Contact Tank When the WWTP is discharging to the stream, effluent flows by gravity from the Effluent Pump Station to the chlorine contact tank, and then to the cascade steps aeration, and then the outfall.

The isolation gates in the chlorine contact tank are beyond their expected life and need replacement. The concrete tank is in fair shape.

As a back up to the UV disinfection system, when flowing to the stream, sodium hypochlorite solution can be added to the Effluent Pump Station, with subsequent dechlorination at the end of the chlorine contact tank.

4.6.2.9 Chemical Addition In the past, polyaluminum chloride (PACl) solution was added to the SBR to precipitate ortho-phosphorus for subsequent removal through settling, and in the cloth media filter. PACl dosing consisted of a dosing pump pulling solution from a drum. PACl has not been used recently since the WWTP has been able to meet their target effluent phosphorus levels by biological phosphorus (bio-P) uptake without the use of additional chemicals.

Sodium hypochlorite solution is used in cleaning the cloth media filter, and as a back up to the UV disinfection process. Sodium hypochlorite dosing consists of a dosing pump pulling solution from a tote.

4.6.2.10 Existing Electrical System The existing electrical service for Centreville Water Wastewater Treatment Plant is provided from Delmarva Power (DP) company owned 500 kVA, 25 kV to 480/277-volt, 3 phase, 4 wire, pad mounted transformer. The existing transformer secondary feeders installed underground to serve an 800-amp main distribution panel (MDP) via an 800-amp enclosed circuit breaker and an 800-amp automatic transfer switch (ATS) with bypass located in

the existing electrical room of the Filter and Blower Building. A 500kW engine driven generator provides backup power.

The existing MDP serves the existing WWTP buildings including the existing Panel DP in the electrical room, 600- amp motor control centers (MCC) A and B in the Blower room and a 75 kVA transformer located outside of the existing Lab Building. The existing Panel DP, 400 amp, 480/277 volt, 3 phase, 4 wire, serves the lighting, 3 phase motors and a 30 kVA, 480-208/120 volt, 3 phase, 4 wire, dry type transformer mounted on the wall to serve the

existing Panel PA, 100-amp, 208/120 volt, 3 phase, 4 wire for the receptacles and miscellaneous loads.

The existing Lab Building Is served by a 75 kVA, 480-208/120-volt, 3 phase, 4 wire pad mounted dry type transformer outside of the building. The existing transformer feeders enter the building via old CT cabinet to a 400-amp distribution panel which in turn serves the existing MCC, Panel PC and Panel PD. The existing MCC is located in the existing Lab Building workroom and the Panel PD is located in the Pump Building (old Admin

Building).

Page 42 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 4.6.2.11 Existing Controls System The plant currently has no centralized monitoring or control system for operation of the plant. Currently all operations are performed manually by operators physically going to the process areas and starting and stopping equipment as required. Operators must go to the different instruments throughout the plant to take readings and

manually collect process data.

The SBR system is provided with the manufacturer’s Programmable Logic Control (PLC) based control panel to provide for automatic operations of the system. However, the system must be started locally at the control panel and process data is only able to be monitored at panel mounted interface screen. The manufacturers control panel is corroded beyond its useful life. The floor stands for the panel enclosure are almost entirely decayed by

rust with the weight of the panel seemingly supported by the conduits entering at the bottom of the panel.

The PLC controller in the SBR control panel is also at the end of its supported lifecycle. The manufacturer of this product has ceased manufacturing this model and no longer supports it for technical assistance, maintenance, or software interface.

Alarms throughout the plant are relayed through an alarm notification system called Mission. The Mission system provides a common trouble alarm for a process area without providing any amplifying information to allow for advanced troubleshooting or prioritizing response. The Mission system is also used at the Town’s pump stations, tanks and water treatment plants for monitoring alarms at these facilities. When an alarm is active, the Mission

system will use a cellular connection to notify operators based on a pre-programmed calling list.

4.6.2.12 Existing Spray Irrigation Effluent Disposal Currently the Town has an MDE discharge permit to spray irrigate 0.542 million gallons per day (MGD) of treated effluent on 223.7 acres of suitable spray area from March 1 to December 15. They have mainly center pivot spray rigs, but also have three fixed head spray nozzles located near the control building. There are ten (10) spray fields with individual approved spray rates that vary from 0.3 inches per week to 2 inches per week, per field.

Currently, they spray at approximately 0.5 MGD among 173.44 acres of irrigation fields. Often the existing fields are sprayed 8 to 12 hours per day.

The Town is not permitted to use chicken manure on the spray fields. They apply chemical fertilizer because more nitrogen is required per the annual Nutrient Management Report than is in the effluent. The nitrogen concentration in the effluent is typically 2 mg/L or lower. At the spray fields the main crop grown is corn, with some soybeans also.

The existing storage pond’s original design was not specified large enough. The pond was built in 2001 when the spray rigs were built.

Water levels and groundwater quality are monitored in ten monitoring wells on a quarterly basis. Water quality is monitored at three stream sites quarterly. On a weekly basis, water levels are measured in ten piezometers which are located near the various center pivots. Permission to spray effluent is conditional on water levels observed in the piezometers.

The surficial geologic formation that underlies the area is Upland Deposits according to the Geologic Map of Maryland (1968). The Upland Deposits are gravel, sand, silt, and clay that were deposited in the Quaternary Period of earth history.

Underneath the Quaternary layer are sediments of the Calvert Formation, which formed in the Tertiary Period.

The upper part of the Calvert Formation is exposed in stream valleys in the Centreville area. At the Town spray field property, the Calvert Formation is represented by a layer of green silty sand exposed in the stream valley.

Page 43 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD According to the Natural Resources Conservation Space (NRCS) Soil Survey of Queen Anne’s County, Maryland the Town spray fields are underlain by soils of the Matapeke-Mattapex-Nassawango map unit. The farms located to the northwest and to the northeast of the Town spray fields are underlain by soils of the Ingleside-Pineyneck-

Unicorn map unit. Soils at both the existing spray fields and the considered expansion farms are both welldrained which is advantageous. Both can also include soils that have a wet substratum.

4.7 Water and Energy Audits The Centreville WWTP is supplied with potable water from the Town’s water treatment and distribution system.

The Town does not currently meter the potable water use. The WWTP does not have an onsite treated effluent water reuse system, and therefore all water used in the treatment and maintenance operations is potable water.

A water audit of current significant uses of potable water was conducted at the site and is summarized in Table 4.14.

Table 4.14: Existing Significant Water Uses Estimated Instantaneous Estimated Average Daily Use Flow Usage gpm gpd Influent Screen Spray 2 1,000 Water SBR Scum Spray Down 5 50 Miscellaneous Cleaning 10 100 During Maintenance The electric usage of the WWTP is only metered for the entire site. The current major energy demands are summarized in Table 4.15.

Table 4.15: Existing Major Electrical Demands Major Electrical Quantity Electric Demand, Each Demands Aeration Blowers 3 50 HP Sludge Holding Aeration

2 30 HP

Blowers SBR Mixers 2 20 HP UV Disinfection 1 15 kW Effluent Pumps 2 20 HP Buil/ding Electric Heat,

- 35 kW, total

Total For the period January 2020 through March of 2023 the WWTP used an average of 1,091 kWh each day. The annual average daily electric usage for 2020 through 2022 is summarized in Table 4.16.

Page 44 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 4.16: Recent Electrical Usage Annual Average Electric Year Demand (kWh / Day) 2020 1,107 2021 1,057 2022 1,048 Page 45 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 5 Need for Project The annual average daily flows from the Centreville WWTP from 2014 to 2022 are shown in Table 5.1, with an

annual average daily flow of 0.40 MGD.

Table 5.1: Historical Centreville Effluent Flow 2014 2015 2016 2017 2018 2019 2020 2021 2022 Annual Average 0.36 0.38 0.36 0.32 0.40 0.44 0.42 0.51 0.41 Flow

(MGD)

The annual average effluent flows have recently exceeded 80% of the existing facility’s permitted flow (0.542 MGD), with the average of the last three calendar years (2020-2022) averaging 0.45 MGD, which is 83% of the permitted flow. As discussed in Section 3.4, the population is expected to continue to grow.

5.1 Health, Sanitation and Security Maintaining the health, sanitation, and safety of the population served, as well as the areas impacted by the disposal of the treated effluent are key drivers for the project.

The influent screen, treatment system aeration capacity, tertiary filter, UV disinfection, and Effluent Pump Station regularly reach their practical operating limits during wet weather events. The systems are operating as designed, and maintenance is timely, but these systems do not have sufficient capacity to handle the full range of flows and loads the WWTP is currently experiencing.

As discussed in Section 5.2, the majority of the treatment plant is reaching 20 years old. The concrete tanks are in excellent condition. The mechanical process systems are reaching the end of their useful life, and the control systems have exceeded their useful life. The SBR main control panel is no longer supported by the manufacturer.

Without the control system operating, a sequencing batch reactor requires a dedicated operator to provide manual operation 24/7. This represents a significant risk to maintaining treatment.

The spray irrigation system is also showing signs that maintaining compliance with the discharge permit requirements will become more challenging as flows increase. During extended wet periods the treated effluent storage lagoon has approached its capacity, and the spray irrigation fields are also approaching their practical limits.

Due to the stress on the treatment plant and disposal sites, and despite the efforts of the Town’s operations department, the NPDES discharge permit has been violated multiple times over the past three years. Further information regarding these violations can be found in the Town’s response to MDE. Regardless, the system continues to age and flows increase the system will approach a tipping point where it is unable to reliably meet

the discharge permits.

5.2 Aging Infrastructure The majority of the WWTP, the effluent storage lagoon and spray irrigation system were brought online in 2005.

Mechanical process equipment at WWTPs has a generally accepted expected life of 20 years. As the equipment exceeds this, the cost to repair the equipment starts to outweigh the cost of replacement. More importantly, when equipment is offline waiting for repairs, it is not available to contribute to the treatment capacity.

Control systems have the shortest expected life of equipment at a WWTP. The specific expected life will depend on the manufacturer continuing to support the hardware and software. With the constant changes and upgrades in processor based systems, the manufacturers must use the currently proven technology to keep costs Page 46 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT

Centreville, MD competitive and can only support so many different systems with spare parts, programming, and updates. The primary hardware in the Centreville sequencing batch reactor’s main control panel is no longer supported by the manufacturer. As such replacement parts are no longer readily available, can take months to find and can be many times the cost of supported systems.

5.3 Reasonable Growth The project is consistent with the Maryland “Smart Growth” legislation which established Priority Funding Areas (PFA). The wastewater treatment plant lies completely within a Maryland Department of Planning PFA. The Queen Anne’s County Comprehensive Plan for Water and Sewer identifies the planned growth for the Town of Centreville and projects a buildout sanitary flow of 1.75 MGD.

As indicated previously, the annual average flows to the WWTP are currently above 80% of the permitted flow, at approximately 0.4 MGD. Developers have approached the Town with conceptual plans for significant housing developments within the Town. Those developments are not practical without the expansion of the WWTP.

Considering the recent average flows, and the known potential for development, increasing the design capacity to 1.0 MGD was selected. The expansion to 1.0 MGD will give the Town many years of planned growth without having a WWTP that is excessively large to treat the recent flows. Projecting out when the new developments will be brought online is difficult, but it is expected the Town could reach 80% of the 1.0 MGD capacity sometime

between 2040 and 2050.

Page 47 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6 Upgrade and Expansion Alternatives The primary goals for the upgraded and expanded treatment process are:

1. Provide ENR levels of treatment and continue compliance with the NPDES discharge permit (refer to

Section 2.3.1).

2. Provide liquid and solids treatment for 1.0 MGD annual average influent flow and associated wet

weather flows.

There are several facilities that require expansion and/or upgrades to accommodate the increased level of treatment and hydraulic throughput regardless of the treatment alternative that is selected. Equipment catalogs for the major equipment described in this section are included in Appendix D.

The three alternatives considered are:

Alternative 1 – Expand the SBR process, expand the post flow equalization tank, and add a denitrifying tertiary filter.

Installing two additional SBR tanks will expand the current process that has been proven to be effective.

The SBR operation is already understood, operating, and maintaining the system will remain straightforward. To accommodate for increased flow, the post equalization tank would also be expanded, and a tertiary denitrifying filter would be added downstream of the SBR. The process will require more space and need to deal with the aging SBR infrastructure. The SBR’s main control panel is no longer supported and finding replacement parts is difficult.

Alternative 2 – Replace the existing SBR system with a 5-stage conventional activated sludge process and add a tertiary filter with denitrifying capability.

This biological process reduces nitrogen and phosphorus compounds by switching between both high and low oxygen environments. Flow passes through distinct anaerobic, anoxic, aeration, post anoxic, and reaeration stages, similar to a “Bardenpho” configuration. The anaerobic zone enriches phosphorusaccumulating organisms that help remove phosphorus in later stages. Denitrification occurs in both anoxic zones, where denitrifying bacteria converts nitrates into nitrogen gas. In the aeration stage,

nitrification occurs, converting ammonia to nitrate, and is recycled to the first anoxic zone. The reaeration stage helps release any more nitrogen gas minimize denitrification occurring within the subsequent clarifier. RAS from the secondary clarifier is pumped to the dewatering facility and the rest of the flow is further treated by a denitrifying filter. Due to the change in treatment technology, additional operator

knowledge will be required to maintain and operate the system.

Alternative 3 – Replace the existing SBR system with to a 5-stage MBR activated sludge process.

The process configuration is similar to Alternative 2 utilizing 5-stages, however solid separation is facilitated via the membrane and not via clarifiers. The membrane has a pore size of approximately 1 micron, that allows water to permeate while retaining the activated sludge in the reactor. The effluent is pulled through the membranes, which are commonly either a tube or plate style, the resulting permeate

has a low turbidity with the excess sludge being removed from the reactor basins. This results in a highquality effluent without the need for a tertiary filter, and results in a compact process that also has a longer sludge retention time. The membrane does limit the hydraulic throughput of the treatment process and an influent flow equalization tank is required upstream of the MBR to ensure flux through the MBR

does not exceed its capacity. The existing SBR tanks would be converted into influent flow equalization tanks. Additionally, knowledge to operate and maintain the new system as well as the additional process equipment compared to the other alternatives, will be required.

In addition to the three alternatives, a ‘do nothing’ option was also initially considered but is not a practical option.

The current flows to the WWTP exceed 80% of the design capacity, and as indicated in the recent performance, Page 48 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD the WWTP has occasionally exceeded the permit limits. Therefore, the existing plant is only marginally capable of treating the existing flows. As the plant equipment ages the repairs and associated downtime will increase, which

will degrade the effective treatment capacity. Refer to Section 5.

6.1 Common Upgrades Upgrades that are common to all three alternatives include:

1. Expand influent screening. Alternatives 1 and 2 will be a 6-mm effective opening screen, and

Alternative 3 will require a 2-mm opening screen.

2. Construct/convert influent flow equalization tank(s).

3. Expand UV disinfection.

4. Expand chemical dosing.

5. Review options for expansion of treated effluent disposal.

6. Install sludge treatment and dewatering.

7. Install an on-site non-potable water system.

8. Miscellaneous refurbishment of reused facilities.

9. Electrical and control system upgrades.

6.1.1 Influent Screening Due to the age of the existing influent screen, difficulty in procuring replacement parts, and to accommodate higher peak flows, it is recommended to replace the screen. The existing screen has performed well, and the operations staff is familiar with operating and maintaining this style of screen. Additionally, the existing concrete channel appears in fair condition and can be reused with some modification and refurbishment (e.g. spalling and

crack repair).

For Alternatives 1 and 2 it is recommended that the replacement screen be the same style as the existing screen.

The existing mechanical screen bypass channel and manual bar rack would remain in place to serve as back up to the additional mechanical screen.

The influent screen for Alternatives 1 and 2 would comply with the design criteria in Table 6.1.

Table 6.1: Influent Mechanical Screen Design Basis – Alternatives 1 and 2 Parameter Value Units Quantity, Duty/Standby 1/0 Unit Peak Flow 4 MGD Screen Opening 6 mm Screen Basket Diameter 40 Inches Integrated Screenings Ancillary Equipment Washer/Compactor with - Bagger Basis of Design Lakeside – Raptor - Alternative 3 – MBR Activated Sludge requires a more robust screening system with smaller openings to protect

the membranes. For Alternative 3, it is recommended to provide both coarse and fine screens in series, with 1 duty and 1 standby screen for each size. The existing screen channels will be expanded to add a channel for a second coarse screen. The existing screen will be replaced. A dual channel fine screen facility will be constructed to the north of the existing screens. The influent screen for Alternative 3 would comply with the design criteria in

Table 6.2.

Page 49 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.2: Influent Mechanical Screen Design Basis – Alternative 3 Parameter Value Units Coarse Screens Quantity, Duty/Standby 1/1 Unit Peak Flow, Each

4 MGD

Screen Screen Opening ½ inch Screenings Ancillary Equipment Washer/Compactor with - Bagger Basis of Design Duperon Low Flow - Fine Screens Quantity, Duty/Standby 1/1 Unit Peak Flow, Each

4 MGD

Screen Screen Opening 2 mm Screenings Ancillary Equipment Washer/Compactor with - Bagger Basis of Design Huber Band Screen - 6.1.2 Influent Flow Equalization Tank To accommodate fluctuations in influent flows during wet weather events, an influent flow equalization (EQ) tank is recommended for each alternative. The equalization tank will reduce the peak flows (peak shaving) to the SBRs, activated sludge basins, or MBRs and therefore improve the effluent quality during wet weather events.

The influent flow EQ tank will be designed to provide wet weather peak flow shaving at the 1.0 MGD annual average flow conditions. Since the current influent flows are not measured, the tank will be sized based on typical municipal peak flow characteristics. A conservative peak day peaking factor of 3 will be used, therefore a peak day flow of 3.0 MGD is expected. A 500,000-gallon working volume concrete tank is recommended to reduce the

peak day flow through the treatment process to 2.5 MG. Redundant 750 gpm submersible pumps with variable frequency drives (VFD) will be mounted in the EQ tank to pump flow that is diverted from the EQ tank to the SBRs, activated sludge basins, or MBRs.

For Alternative 1 – SBR, a new 500,000-gallon working volume tank would need to be constructed onsite. For Alternative 2 – Conventional Activated Sludge and Alternative 3 – MBR Activated Sludge, the existing SBR tanks can be converted into two (2) influent flow EQ tanks. As shown in Table 4.9, each existing SBR tank has a maximum working capacity of 0.589 MG. Refer to Section 6.3 for site plan layouts for each alternative.

6.1.3 UV Disinfection The existing UV system was upgraded after 2005 and is operating well; however, it is undersized to handle the peak day flow following the expansion to 1.0 MG annual average influent flow and associated wet weather flows.

To better utilize the space available in the Filter and Blower Building, the existing UV system will be replaced with an enclosed low pressure high output inline system. Table 6.3 summarizes the design basis for the replacement system.

Page 50 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.3: UV Disinfection Replacement System Design Basis Parameter Value Units Quantity, Duty/Standby 1/1 - Configuration Parallel - Peak Day Flow 3.3 MGD Design Transmittance 65 % UV Dose > 40 mJ/cm2 Effluent Quality < 116(1) MPN/100 mL E. Coli Number of Lamps, each unit 20 800W each, LPHO ETS – UV System,

Basis of Design manufactured by - Evoqua

(1) – Note that effluent quality limit would be 14 MPN/100 mL E. Coli if the new

outfall extension is used, per Section 6.1.5.

6.1.4 Chemical Dosing For the ENR upgrade of the Centreville WWTP, chemical addition for increased phosphorus removal will be required. The existing chemical dosing system will be expanded for additional polyaluminum chloride (PACl) and methanol dosing. Increased dosing of PACl is required to precipitate higher concentrations of ortho-phosphorus in order to meet a TP concentration less than 0.3 mg/L, as required by ENR. To meet the target TP concentration,

an estimated 240 gallons per day (gpd) of PACl will be required. PACl will be dosed upstream of the denitrification filters for Alternatives 1 and 2, and downstream of the MBR process for Alternative 3. PACl dosing capacity will be increased by replacing the existing PACl drums with an 8,000-gallon capacity double contained PACl bulk storage tank located in the Filter and Blower Building. Alternatively, two (2) 4,000-gallon double contained tanks may be

installed for PACl storage, if the Filter and Blower Building cannot accommodate a single larger tank. 8,000 gallons of PACl storage will provide over 30 days of chemical storage. The existing PACl dosing pumps will likely need to be replaced to accommodate a higher capacity.

Each alternative will also include methanol dosing to aid in additional nitrate removal and subsequent reductions in TN concentration less than 3 mg/L, as required by ENR. To meet the target TN concentration, an estimated 65 gpd of methanol will be required. For Alternatives 1 and 2, methanol would be dosed just upstream of the denitrification filters. For Alternative 3, methanol would be dosed within the MBR tank. Methanol will be stored in a

4,000-gallon double contained bulk storage tank, within or outside of the Filter and Blower Building for Alternatives 1 and 2, or within the MBR Process Building for Alternative 3. 4,000 gallons of methanol storage will provide over 40 days of chemical storage.

6.1.5 Review of Effluent Disposal Options As previously mentioned, Centreville WWTP currently discharges to Gravel Run through an existing outfall during the cold weather months (December 1 to March 31). During the warmer weather months (April 1 to November 30), effluent is discharged to the Town’s spray irrigation site. Previously, Centreville WWTP was permitted to utilize spray disposal year round; however, with the most recent permit update in 2010 and updated MDE

requirements, spray disposal is restricted to March 1 to December 15.

At the Town’s current spray irrigation disposal site, there is a total usable disposal area of 173.44 acres. The disposal site is reported to be near capacity at current flows. Concurrently with the ENR expansion and upgrade of the Centreville WWTP, the Town is actively pursuing expansion of the effluent disposal capacity to accommodate the expected increase in WWTP influent flows.

The Town has unsuccessfully pursued expanding its spray irrigation area, despite years of searching for suitable land. Other water reuse options, such as indirect potable reuse (IPR), have been discussed but are not Page 51 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD considered feasible in the near term. Therefore, expanding the surface water discharge to allow year-round

discharge is currently the most viable approach. This section provides a brief overview of the proposed work to expand the surface water discharge effluent disposal.

6.1.5.1 Year Round Stream Discharge To allow for year-round surface discharge, the Town is proposing to relocate the plant outfall to Corsica River at a location downstream of the Watson Road Bridge, which would be consistent with MDE’s approved report for TMDL of Nutrients for Corsica River (May 2000).

The Town is proposing to manage the plant’s expanded effluent flow by maximizing use of the existing spray irrigation field capacity in combination with discharge to a new Corsica River outfall within the TMDL nutrient limits. During the irrigation season, the current permitted flow (0.542 MGD) will be applied to the fields with the remaining effluent flows (0.458 MGD) to Corsica River. Outside the irrigation period, all flows would be discharged

to Corsica River. The assumption for this scenario is ENR effluent quality with a consistent treatment performance of 3 mg/L and 0.3 mg/L for TN and TP, respectively. It should be noted that MDE has recently proposed a more stringent TP limit of 0.15 mg/L (i.e. 50% further reduction) if year-round stream discharge is selected. This would allow for a nutrient loading to Corsica River that is well below the established TMDL limits for low flow periods and

for the total annual limit. These assumptions provide a good overall nutrient load margin of safety, especially during low flow (warm) periods where nutrient loads to Corsica River are most critical and where the utilization of the spray fields is greater.

With year-round surface discharge, upgrades to the existing Effluent Pump Station will be required to send additional flow through the new outfall pipe and further into the Corsica River. Additionally, a shellfish protection tank will be required. The tank will need to be sized for 24 hours of holding of the design average flow, or 1,000,000 gallons. The tank will be used to stop all wastewater from flowing to the stream if the effluent quality is

poor or the disinfection system is offline. Upgrades to the Effluent Pump Station and construction of the shellfish protection tank are not recommended at this time as part of the ENR upgrade and expansion.

6.1.6 Biosolids Handling The dewatered biosolids are currently disposed of in a landfill. By providing sufficient solids retention time in an aerobic digester, a Class B biosolids would be produced. This potentially could allow for land application of the dewatered biosolids.

For Alternative 1 – SBR, a new aerobic digester would be constructed in the footprint of the existing reed drying beds. For Alternative 2 – Conventional Activated Sludge and Alternative 3 – MBR Activated Sludge, the existing post equalization and sludge storage tanks will be retrofitted to be aerobic digesters. Refer to Section 6.3 for site plan layouts for each alternative. The design criteria for the aerobic digester are provided in Table 6.4.

Table 6.4: Aerobic Digester Design Criteria Parameter Value Units Design Waste Sludge 16,000 gallons/day 1,300 Lbs dry solids/day 10,000 Mg-TSS/L Digester Solids Concentration with Settling and Decant 20,000 Mg-TSS/L Solids Retention Time 60 days Number of Tanks 2 - Working Volume, each 250,000(1) gallons Working Volume, Total 500,000(2) gallons Surface Aerator Mixers (3 in each Tank) 20 HP/each

(1) – For Alternatives 2 and 3, the retrofitted aerobic digesters will have an approximate working volume of

175,000 gallons each.

Page 52 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

(2) – For Alternatives 2 and 3, the retrofitted aerobic digesters will have an approximate total working volume of

350,000 gallons.

There are several proven, reliable sludge dewatering methods that can be applied to Centreville WWTP. Similar to the treatment process, a primary consideration should be that the equipment is straightforward to operate and maintain. One widely utilized technology across the wastewater industry is the belt filter press (BFP). See Figure 6.1 for a BFP. BPFs have many advantages, including:

• Low capital cost,

• Low energy consumption,

• Simple operation and maintenance, and

• Ability to handle stringy solids (i.e. rags) and plastics.

Prior to sludge being deposited on the BFP, the sludge is conditioned with polymer to promote the coagulation of solids. The polymers would be received in a concentrated liquid format in 55-gallon drums. Polymer would be pumped by peristaltic pump to a make down tank, a 300-500-gallon fiberglass tank where potable water is added to condition the polymer and get the proper concentration for dosing. The polymer solution is then pumped into an

injection ring located in the belt filter press feed pipeline and mixed in-line with the sludge.

During the dewatering operation, as the dewatered cake is discharged, the press belts are continuously washed with spray water. A wash water skid equipped with a booster pump will provide the pressure to adequately wash the belts.

The cake will be discharged from the belt filter press onto a belt conveyor which conveys the cake into a roll off storage container until it is taken for disposal.

Another technology considered is the volute dewatering press. The volute dewatering press is similar in overall configuration to a screw press, with a center conveying screw pushing the solids that are larger than the openings in the dewatering drum towards the discharge end. See Figure 6.2 for a volute dewatering press, and Figure 6.3 for a typical screw press. The screw press uses a static perforated, or slotted drum which separates the solids.

The volute press utilizes the annular space between donut shaped plates to separate out the solids. The screw and volute press both have low capital costs and low energy consumption.

The volute dewatering press and screw press have fewer moving parts than the belt filter press which should translate to lower maintenance costs.

The BFP has low capital cost and low energy consumption as advantages that have led to numerous installations.

The dewatering equipment will be further evaluated during the design of the expansion.

A dewatered cake storage area will be provided with a permeable asphalt floor and a pre-engineered clear span roof.

Page 53 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 6.1: Belt Filter Press (Credit: Andritz) Figure 6.2: Volute Dewatering Press (Credit: Process Wastewater Technologies, LLC) Page 54 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 6.3: Screw Press (Credit: Schwing Bioset, Inc.) To expand the biosolids handling process and to house additional equipment, a Dewatering Facility and Covered

Cake Storage Facility will be constructed onsite. Refer to Section 6.3 for site plan layouts for each alternative.

The Dewatering Facility will consist of the following architectural characteristics:

• 4-inch Brick veneer with CMU block bearing wall, with steel roof trusses, and standing seam metal roof.

• Fiberglass reinforced plastic (FRP) doors, windows, frames, etc., as required, with new reinforced

concrete slab.

• This building will be an enclosure for covering sludge tanks.

• One bay will be two stories for covering the sludge tanks, and the other bay will be one story for vehicles.

The Covered Cake Storage Facility will consist of the following architectural characteristics:

• Pre-engineered steel portal framed building with standing seam metal roof, with all four sides open to the

exterior, over a new reinforced concrete slab.

6.1.7 Non-Potable Water System A non-potable water system will be installed to be used in a variety of applications throughout the WWTP. The non-potable water system will allow for onsite reuse of the treated plant water and subsequent reduction in potable water demand at the WWTP. Currently, the WWTP utilizes potable water for all its water needs.

Installation of a non-potable water system will result in a cost savings for plant operation, as well as an increase in efficiency of the WWTP. Refer to Section 6.5.1 for additional water and energy efficiency considerations for this project.

The non-potable water system will be installed within the Filter and Blower Building. The system will be skid mounted and have an approximate capacity of 200 gpm. The system will draw non-potable water supply from the UV effluent and have non-potable storage in an approximately 5,000-gallon capacity tank. Pumps mounted on the skid will draw non-potable water from the tank and pump to a distribution system throughout the WWTP. Nonpotable water can be used for applications such as spray water for the influent screens, pump seal water, wash

down, or yard hydrants throughout the WWTP.

Page 55 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.1.8 Laboratory and Administration Building The current Laboratory and Administration Building was not designed to accommodate the number of current operators. For example, the building does not have a designated office space. Instead desks are placed in the electrical distribution room, and in the entryway. The restroom was designed for single occupancy and is serving

as the locker/changing room. In addition, the plant expansion, and the move to more stringent ENR effluent quality will result in an increase in the quantity and type of laboratory tests that are needed to maintain process control.

The expansion project will include the renovation of the existing space including the demolition of the existing laboratory cabinets and restroom. The available space will be re-allocated to provide separate spaces for:

• Laboratory

• Office Space

• Separate locker room with shower and bathroom

• Electrical Distribution and Control Room

The existing Lab Building consists of 4-inch Brick veneer with CMU block bearing walls, with steel roof trusses, asphalt fiberglass roof, and existing hollow metal doors, windows, frames. The existing structure is to remain and be painted as required. The interior spaces will be renovated with new finishes, including acoustical ceilings, painted walls, doors, and frames, casework, fixtures, etc. A roof leak was discovered at a portion of the existing

asphalt fiberglass roof while onsite, which will be repaired or replaced as necessary. Figure 6.4 shows the existing Lab Building.

Figure 6.4: Existing Lab Building 6.1.9 Filter and Blower Building The existing Filter and Blower Building consists of 4-inch Brick veneer with CMU block bearing walls, with steel roof trusses, asphalt fiberglass roof, and existing hollow metal doors, windows, frames. The existing structure is to remain and be painted as required. Interior work will include removal of existing process equipment, expansion of

the electrical room, replacement of the existing filters and UV system, expansion of the PACl chemical storage and dosing system, and replacement of the MCC’s. New finishes, including acoustical ceilings, painted walls, doors, and frames, casework, fixtures, etc., will be provided. Figure 6.5 shows the existing Filter and Blower Building.

Page 56 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Figure 6.5: Existing Filter and Blower Building 6.1.10 Control Building The existing Control Building consists of 4-inch Brick veneer with CMU block bearing walls, with steel roof trusses, asphalt fiberglass roof, and existing hollow metal doors, windows, frames. The existing structure is to remain and be painted as required. The interior spaces will be removed and refurbished for other uses. New

finishes, including acoustical ceilings, painted walls, doors, and frames, casework, fixtures, etc., will be provided.

Figure 6.6 shows the existing Control Building.

Figure 6.6: Existing Control Building Page 57 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.1.11 Electrical System Upgrades The electrical system upgrades proposed herein include all three treatment alternatives, with the exception of the MBR Process Building (see Section 6.1.11.7), which would only be required for Alternative 3 (MBR Activated Sludge). The existing electrical loads for the WWTP utilize approximately 25% (peak demand of 101 kW and

average demand of 90 kW) of the existing 500 kVA transformer capacity, and the existing incoming electrical equipment in the Filter and Blower Building will not require electrical upgrade. The existing 500kW engine driven generator is sufficiently sized for the planned expansions.

6.1.11.1 Filter and Blower Building The existing electrical equipment, including an enclosed circuit breaker, automatic transfer switch, panelboards MDP, DP and PA, and low voltage transformer, in the electrical room is in fair condition. However, the existing MCC’s in the Blower Room should be replaced with new MCC’s. The existing circuit breakers in the existing MCC’s located have been overheated and tripped in the summer months even with portable fans blowing directly

towards the MCC’s. High ambient temperature is the worst enemy for the electrical equipment and shortens the life of the electrical equipment.

Therefore, the existing MCC’s should be replaced with new MCC’s in a new conditioned space in the Filter and Blower Building to prolong the equipment’s life and avoid any nuisance tripping from the heat. The new MCC will be sized per the motor list, shall be bigger than the previous two MCC’s, and will consolidate the existing as well as new process loads. All the branch circuits from this MCC will be new with a new feeder circuit from panelboard

MDP.

6.1.11.2 Lab Building The existing electrical equipment in the Lab Building is antiquated and should be replaced with new electrical equipment, including the transformer outside (which has been damaged and moved), switchboard, and Panel PC.

Moreover, this equipment is original equipment that was not updated to properly protect the electrical loads/equipment and do not have proper working clearance in accordance with the National Electrical Code (NEC) due to the existing work benches, microwave oven, and refrigerator. All existing feeders and branch circuit wiring in the building should be replaced with new conduit and wires. All new LED lighting and receptacles will

also be provided based on the new building layout.

6.1.11.3 Pump Building (Old Control/Admin Building) The existing Panel PD is a relatively new panel in good condition and has proper working clearance. The existing panel will remain. However, the existing feeder from the Lab Building shall be replaced from a new distribution panel.

6.1.11.4 Replacement Influent Screening The screens are being replaced, and a new control panel complete with variable frequency drives (VFDs), circuit breakers, and controls will be provided outside mounted on a strut frame.

6.1.11.5 New Dewatering Facility A new feeder will be run to this building, and new distribution equipment will be provided, including panelboards and dry type transformers. Electrical fixtures including receptacles, lighting, and switches will also be provided.

Page 58 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.1.11.6 New MBR Process Building For Alternative 3 – MBR Activated Sludge, a new feeder will be run to the MBR Process Building, and new distribution equipment will be provided, including panelboards and dry type transformers. Electrical fixtures including receptacles, lighting, and switches will also be provided.

6.1.11.7 General Site Electrical The new electrical loads are anticipated to double, and a 150 kVA pad mounted transformer and a 600-amp distribution panel are proposed to accommodate the proposed treatment facility electrical loads and spare capacity. All new feeders and branch circuit breakers shall be properly protected. Site lighting shall be provided per revised layout plan. All outside feeders shall run in underground ductbank system.

In summary, the following electrical upgrades are proposed:

1. Existing service is adequate for all three alternatives and shall be retained.

2. Replace interior lighting for the whole plant with LED lighting.

3. Provide new lighting and controls for new proposed building.

4. Provide new LED site lighting for the whole plant.

5. Replace existing MCCs with new in the Filter and Blower Building.

6. New feeders and branch circuits for proposed upgrades.

7. New panelboards, feeders, branch circuits and fixtures for Lab building, MBR Process building and

Dewatering Facility.

8. Provide new ductbank system.

9. Provide new site lighting.

6.1.12 Control System Upgrades To help achieve the operational goals of the advance treatment systems proposed, a centralized Plant Control System (PCS) should be developed to provide the ability for centralized monitoring and supervisory control.

Individual processes should be provided with a dedicated PLC control panel that will provide the local control for the individual process equipment and collect process data from local instruments.

Centralized supervisory control would allow operators to interface with the local PLC based control systems that are providing process control at the different process facilities. The distributed nature of this type of system builds reliability into the system by not relying on a single processor to remotely control a process. If there is a failure in communications or a local control panel, the remaining system will continue to operate based on programming

and commands issued locally by the dedicated processor. This type of system saves on the installation of conduit and wire by locating the controller near the process area and also allows for the use of less expensive control equipment that has lower total memory and input/output point capability to control a limited scope of equipment.

The PCS system will collect monitored process data from field instrumentation and archive these data in a historian function. The data historian will allow for review of operations through historical trends and creating daily/monthly or annual reports. The automated and centralized collection of these data will facilitate in optimizing the process control resulting in possible savings in energy, chemicals and reduced workloads while providing the

data trail to ensure regulatory compliance.

The PCS should be extended to provide remote monitoring of the pump stations, tanks and water treatment plants throughout the town. Similar type of local control panels should be located at these facilities to replace the aged control equipment and to communicate with the centralized PCS. Using the PCS to interface with these other facilities is practical in the sense that it makes full use of the software and hardware that will be purchased

for the wastewater treatment plant. These systems are scalable to allow for additional capacity without impeding on the overall efficiency or functions for the plant.

Page 59 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Communications between the WWTP centralized PCS and the remote sites will most efficiently be performed through the use of cellular network technology. Using a third-party cellular provider for remote communications is a low-cost solution that makes use of the providers existing infrastructure and security practices at established

low-cost GSA pricing.

6.2 Treatment Alternative Upgrades Three (3) alternatives to upgrade and expand the Centreville WWTP have been developed. The different upgrades that are required for each treatment alternative are detailed below. Preliminary hydraulic profiles for each of the three alternatives is included in Appendix E.

6.2.1 Alternative 1 – Expand the Sequencing Batch Reactor 6.2.1.1 SBR Process Expanding the existing SBR process from 0.542 MGD to 1.0 MGD to provide the design effluent quality would require the following major scope components:

• Construct a 1.0 MG influent flow equalization basin

• Construct two (2) additional SBR tanks outside of the existing SBR tank structure with floating mixers,

removable fine bubble aeration grids, and decant arms.

• Double the capacity of the existing post equalization (post EQ) tank by removing the dividing wall between the

existing post EQ tank and sludge holding tank and replacing the equipment.

• Install denitrification filters and a denitrification filter control building and pump station.

• Install three (3) additional blowers in the existing blower room.

• Add storage and handling for the addition of an external carbon source (methanol) to SBR.

Refer to Section 4.5.1 for a description of the SBR treatment process. Table 6.5 outlines the design specifications for the SBRs.

Page 60 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.5: SBR Design Basis Parameter Value Units No. of Basins 4 - Length, each 70.5 Ft Width, each 53.2 Ft Volume each at Avg.

0.47 Million Gallons Side Water Depth Cycles/day 5 Per day/basin Cycle Duration 4.8 Hr/cycle Food to Mass Ratio 0.064 Lbs BOD5/lb MLSS-Day Mixed Liquor Mg/l at Min. Water Suspended Solids 4,000 Depth (MLSS) Concentration Hydraulic Retention Days at Avg Water 1.17 Time Depth Solids Retention Time 17.9 Days Estimated Dry Sludge 1,984 Lbs WAS/Day Produced Actual Oxygen Required 7,453 Lbs O2/Day Air Flowrate per Basin 1,670 SCFM

6.2.1.2 SBR with Aerobic Granular Sludge If Alternative 1 is pursued, there is an option to decrease the required SBR tank capacity by installing an AquaNereda® Aerobic Granular Sludge process, manufactured by Aqua-Aerobic Systems, within the SBRs. The AquaNereda® Aerobic Granular Sludge process uses an optimized batch cycle structure with granular sludge to decrease settling time. Therefore, it can operate at higher concentrations, allowing for more treatment capacity

within the existing tank volume.

The main benefit of the SBR with aerobic granular sludge option is that only three (3) total SBR tanks would be required, rather than four (4) SBR tanks that are required for the standard SBR Alternative 1. This would increase and optimize the amount of available site space at the WWTP. However, costs of the SBR with aerobic granular sludge option include the cost of the SBR granular sludge equipment, which is estimated to be approximately

25% higher than the cost of the standard SBR Alternative 1 equipment, and there have been limited installation of aerobic granular sludge in the U.S. Therefore, other alternatives were pursued instead.

6.2.1.3 Effluent Filtering Due to the hydraulic limitations the existing cloth media filter will be replaced with a deep bed downflow intermittent backwash sand media filter (IBF). As an additional benefit, with the addition of a carbon source, the IBF will be able to simultaneously denitrify the secondary effluent from the SBR, as well as remove particulate solids.

The IBFs are deep mono media type filters where the influent wastewater flows into the filter by overflowing a weir at the top of the filter. The water flows downward through the sand media, support gravel and underdrain. The treated effluent flows out of the bottom of the filter into the effluent pipeline and to the treated effluent clearwell.

The bed is backwashed by pumping water from the clearwell into the bottom of the filter where the underdrain distributes the treated effluent across the filter. The backwash water overflows the influent weir and is discharged, by automatic valves and associated piping, into the mudwell. The biofilm develops on the sand media and sufficient biomass remains in place through the backwash process.

Page 61 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD In the denitrifying mode, a carbon source is required. Methanol or glycerin will be added to the filter influent and the nitrate in the influent is converted to nitrogen gas that escapes the process. In the IBF process the removal of solids and excess biomass produced in the denitrifying mode is accomplished through the intermittent backwash

of the sand media bed.

In denitrifying mode, the IBF can reliably achieve less than 1.0 mg/L nitrate, even at high influent nitrate concentrations. During maximum month design conditions, the nitrate levels will be less than 12 mg/L, making the IBF a reliable treatment process.

The IBF systems also remove total phosphorus as a result of the particulate solids capture and from a small fraction of biological consumption of soluble phosphorus, typically less than 0.02 mg/L per mg/L nitrate removed.

While simultaneous denitrification and phosphorus removal through chemical addition and precipitation can be achieved in the filter, chemical phosphorus removal will be performed upstream of the DN filter stage, i.e. in the SBR or activated sludge process.

The number of filter cells required depends on both hydraulic (peak) flow (relative to filter headloss) and nitrate loading (performance efficiency). Based on the 1.0 MGD design conditions (average and maximum month) the IBF process would consist of three (3) filter cells (144 SF of filtration area per filter cell), for a total of 2,592 CF of active filtration volume.

The IBF filters would consist of concrete above grade tanks with influent channels integrated into the structure.

An online nutrient analyzer will be installed in a small building adjacent to the filters. The analyzer will have centrifugal pumps recirculating flow from the sample points (filter influent and effluent) to the analyzer and back to just downstream of the sample point. One sample pump will draw water from the denitrification filter pump station discharge pipeline (influent). The sample point will be up stream of the methanol injection point. A second sample

pump will draw water from the denitrification filter discharge pipeline (effluent).

A control system for controlling the filtration and backwashing operations of three filters will be located in the new building, roughly 28’ by 10’, including level transmitters, sensors, control panels, analyzers, and a magnetic flow meter (i.e. magmeter). The external carbon storage tank and dosing system will be located adjacent to the IBF.

Two (2) submersible backwash pumps (25 HP each), two (2) submersible mudwell pumps (6.5 HP each), and two

(2) positive displacement blowers will be provided.

The design specifications for the IBF are shown in Table 6.6.

Page 62 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.6: Denitrifying Filter Design Basis Parameter Value Units Quantity 3 Total Unit Average Design Flow, total 1.0 MGD Maximum Month Flow, total 1.2 MGD Peak Flow, total 3.3 MGD Avg TSS to Filter 30 mg/l Nitrate and Nitrite to Filter < 8.0 mg/l Filtration Area, Each 144 sq feet Filtration Area, Total 432 sq feet

Filter Media Depth 72 inches Avg TSS from Filter < 5.0 mg/l Nitrate and Nitrite from Filter < 1.0 mg/l Hydraulic Loading Rate < 2.2 gpm/sq feet (average) Hydraulic Loading Rate < 3.0 gpm/sq feet (maximum month) Hydraulic Loading Rate < 8.0 gpm/sq feet (peak flow) Backwash Frequency 24 Hrs Backwash rate 5-6 gpm/sq feet Backwash Cycle Duration 20-25 min Backwash Volume 17,280 gallons Integrated Controls and

Ancillary Equipment - Backwash System elimi-NITE Denitrification Basis of Design System, manufactured by - Leopold 6.2.1.4 Post Equalization Tank Additional post equalization tank capacity will be required for the expansion. For Alternative 1, the existing sludge holding tank would be converted for additional post equalization tank capacity. The concrete wall that currently separates the existing post equalization tank and existing sludge holding tank would be demolished to effectively

double the capacity of the existing post equalization tank. New surface agitators will be installed in the post equalization tank.

6.2.2 Alternative 2 – Conventional Activated Sludge 6.2.2.1 Activated Sludge Process Conversion of the existing SBR process to a conventional activated sludge process to provide the design effluent quality, as well as expand the design capacity from 0.542 MGD to 1.0 MGD would require the following major scope components:

• Construct two (2) 5-stage activated sludge basins and two (2) rectangular secondary clarifiers with doublesided weirs.

• Convert the existing SBR tanks to two (2) separate influent flow equalization tanks, as described in Section

6.1.2, and convert the existing post EQ tank and the existing sludge holding tank into two (2) aerobic digesters, as described in Section 6.1.6.

Page 63 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

• Install denitrification filters and a denitrification filter control building and pump station.

Most of the site is steeply sloped and is constrained on all sides from expansion. The rectangular clarifiers can integrate the RAS pumping into the footprint of the clarifiers, and with common wall construction occupy less area compared to circular clarifiers with separate RAS pump stations. Therefore, rectangular secondary clarifiers were selected over the more common circular clarifiers.

Figure 6.4 depicts a schematic of the 5-stage process. Influent first flows through an anerobic tank, where oxygen devoid conditions are conducive to phosphorus-accumulating organisms to release phosphate into the wastewater, ensuring it is more readily available to be removed in the further stages than if it remained in biomass.

Flow then enters the first anoxic zone where the majority of denitrification occurs. Denitrifying bacteria use nitrate as an electron acceptor to covert its nitrogen through a series of steps, ultimately becoming nitrogen gas.

The water then enters the aerobic zone where nitrification primarily occurs. Through aerobic bacteria, ammonium is oxidized to nitrite and ultimately nitrate, where it is then recycled, called mixed liquor, to the previous stage for denitrification.

Next, the post anoxic zone aids with removing nitrates from the previous aerobic zone that are not recycled back to the first anoxic zone. A carbon source may be supplemented here to aid in nitrification. Methanol is one ideal substance; however, due to Maryland's colder climate, it may only prove effective with attached-growth media.

Other carbon sources such as acetate, ethanol, or sugar are suitable carbon sources for ordinary bacteria (methanol requires slow growing methylotrophic bacteria) that can still be effective to cooler climates.

Fine bubble diffusers incorporate air in the final rearation zone to help release any more nitrogen gas that has formed as well as minimize inhibit any more denitrification from occurring in the following secondary clarifiers.

This will allow the sludge to settle better and ensure no potential nitrogen gas bubbles form and rise and mixing the water in the process.

As mentioned, water flows to secondary clarifiers following the 5-stage process, where it then flows to a denitrification filter for further nitrogen removal. RAS from the secondary clarifiers is pumped to the Dewatering Facility by submersible pumps within the secondary clarifiers. Design specifications for the denitrification filter are discussed in Section 6.2.1.3.

Some key differences between a 5-stage activated sludge process and SBR include that 5-stage activated sludge process will have continuous flow while an SBR delivers flow in batches, which could play a role in treatment efficacy of other treatment technologies like UV disinfection. 5-stage processes are typically favored for nutrient removal, as it can simultaneously remove nitrogen and phosphorus. However, it has a higher footprint and has a

higher energy consumption. A schematic overview of the 5-stage process is depicted in Figure 6.7.

Figure 6.7: Schematic of 5-Stage Process (Credit: EPA) Page 64 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Design criteria for the 5-stage activated sludge basins and the secondary clarifiers are listed in Tables 6.7 and 6.8, respectively.

Table 6.7: 5-Stage Activated Sludge Basin Design Basis Parameter Value Units No. of Trains 2 Trains No. of Stages 5 - Length of Train, each 95 ft Width of Train, each 35 ft Average Side Water Depth 18.1 ft Volume each at Average Side 0.45 Million Gallons Water Depth Solids Retention Time

10-20 Days

RAS Recycle Ratio 50-100 % Internal Nitrate Recycle 300 % MLSS Concentration 3000-4000 mg/L HRT 1st Zone (Anaerobic) 0.5-1.5 (MMF Design: 1) Hr Anaerobic Zone Working 25,000 Gallons Volume (each train) HRT 2nd Zone (Pre Anoxic) 1-3 (MMF Design: 2) Hr Pre Anoxic Zone Working 50,000 Gallons Volume (each train) HRT 3rd (Aerobic) 4-12 (MMF Design: 10) Hr Aerobic Zone Working Volume 250,000 Gallons (each train)

HRT 4th Stage (Post Anoxic) 2-4 (MMF Design: 4) Hr Post Anoxic Zone Working 100,000 Gallons Volume (each train) HRT 5th Stage (Reaeration) 0.5-1 (MMF Design: 1) Hr Reaeration Zone Working 25,000 Gallons Volume (each train) Total Design HRT 18 Hr

• HRT = Hydraulic Retention Time

• MMF = Maximum Monthly Flow

Page 65 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.8: Secondary Clarifier Design Basis Parameter Value Units No. of Clarifiers 2 - Length, each 60 ft Width, each 35 ft Average Side Water Depth 14 ft Average SOR 250 gpd/sq feet Peak SOR 800 gpd/sq feet Average SOR with one 500 gpd/sq feet Clarifier Offline Average SLR at 100% RAS 14 Lbs/day/sq feet

Peak SLR at 50% RAS 35 Lbs/day/sq feet

• SOR = Surface Overflow Rate

• SLR = Solids Loading Rate

6.2.2.2 Effluent Filtering Similar to Alternative 1 (SBR Expansion), the existing cloth media filter will be replaced with a deep bed downflow IBF. Refer to the description and design basis in Section 6.2.1.3 for the proposed filter upgrades.

6.2.3 Alternative 3 – Membrane Bioreactor (MBR) Activated Sludge 6.2.3.1 MBR Process Conversion of the existing SBR process to a MBR activated sludge process to provide the design effluent quality, as well as expand the design capacity from 0.542 MGD to 1.0 MGD would require the following major scope components:

• Construct a two (2) train 5-stage activated sludge facility, with a larger 5th zone to install MBR equipment.

• Construct an MBR Process Building to house blowers and storage/equipment for the addition of an external

carbon source (methanol) to the MBR.

• Convert the existing SBR tanks to two (2) separate influent flow equalization tanks, as described in Section

6.1.2, and convert the existing post EQ tank and the existing sludge holding tank into two (2) aerobic digesters, as described in Section 6.1.6.

The four stages prior to the MBR system typically include anaerobic, preanoxic, aerobic, and postanoxic stages, similar to the 5-stage activated sludge process. The fifth stage includes the MBR system, which uses a membrane filter with a pore size of approximately 1 micron to allow water to pass through while leaving behind the activated sludge. The effluent is pulled through the membranes, which are commonly either a tube or plate

style, the resulting permeate has a low turbidity with the excess sludge being removed from the reactor basins.

Oftentimes an external carbon source is utilized to aid in nutrient removal like methanol, with other substitutes like ethanol to be evaluated.

This results in a high-quality effluent without the need for a tertiary filter and results in a compact process that also has a longer sludge retention time. Since there is no need for settling, MBR's can also operate at higher mixed liquor suspended solids (MLSS) concentrations.

The membrane limits the hydraulic throughput of the treatment process, so an influent flow equalization tank is required upstream of the MBR to ensure flux through the MBR does not exceed its capacity. MBRs also incur fouling and would need to be cleaned 2-4 times a year with Citric Acid or sodium hypochlorite, although reducing sludge age can reduce fouling.

Page 66 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD The hollow fiber membrane units are cleaned in place which can undergo either a maintenance clean 1-2 times a week or more thorough recovery clean occurring twice a year. Maintenance clean leave the train out of operation for around 30 minutes are done without draining the tank with cleaning solutions reversed through the fibers.

Recovery cleans has the tank filled with permeate and cleaning solution to be soaked for 6-8 hours, which is then neutralized and drained.

MBR’s smaller footprint and high-quality effluent are due to higher volumetric loading rates resulting in lower hydraulic retention times compared to conventional activated sludge (CAS) systems. Although MBRs are energetically more expensive than CAS systems, they have become significantly more efficient in the past 10 years compared to the only slight improvements in CAS technology, becoming 14% less expensive, in relation to

CAS systems.

These advancements are due to primarily the reduction in air scour energy for membrane cleaning due to new diffuser technology, greater membrane packing density, decreased maintenance costs, longer operating life, and increased use of gravity permeation from membranes. MBR's higher energy costs are due membrane aeration and permeate pumps that CAS do not have, as well as the cost of RAS pumping being four times higher in the

MBRs than in a CAS system.

Table 6.9 lists the design specifications of the 5-stage activated sludge basins with the MBR system.

Page 67 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.9: 5-Stage Activated Sludge Basin with MBR Design Basis Parameter Value Units No. of Trains 2 Trains No. of Stages 5 - Length of Train, each 89 ft Width of Train, each 35 ft Average Side Water Depth 18.1 ft Volume each at Average Side 0.42 Million Gallons Water Depth Solids Retention Time

10-20 Days

RAS Recycle Ratio 50-100 % Internal Nitrate Recycle 300 % MLSS Concentration 8000 mg/L HRT 1st Zone (Anaerobic) 0.5-1.5 (MMF Design: 1) Hr Anaerobic Zone Working 25,000 Gallons Volume (each train) HRT 2nd Zone (Pre Anoxic) 1-2 (MMF Design: 1.8) Hr Pre Anoxic Tank Working 45,000 Gallons Volume (each train) HRT 3rd Zone (Aerobic) 4-8 (MMF Design: 7.2) Hr Aerobic Zone Working Volume 180,000 Gallons (each train)

HRT 4th Zone (Post Anoxic) 2-3 (MMF Design: 2.8) Hr Post Anoxic Tank Working 71,000 Gallons Volume (each train) Total Design HRT (including bioreactors and excluding 12 Hr membrane Tanks) No. of Cassettes per Train 3 Cassettes No. of Modules installed per 132 Modules Train Cassette Internal Dimensions 21.7’ x 9’ x 13’ Ft L x W x H Reaeration Zone Working Volume (including membranes, 103,000 Gallons

each train) Membrane Surface Area 113,520 Sq ft Net Flux (Avg Daily) 5.38 gpd/sq feet Net Flux (Max Monthly) 6.46 gpd/sq feet Net Flux (Max Daily) 12.92 gpd/sq feet Net Flux (Peak Hour) 17.76 gpd/sq feet Hydraulic Peak Flux Rate 22.2 gpd/sq feet (Peak Hour) Peak Flux Rate Capacity for healthy biological activity 13.9 gpd/sq feet (Peak Monthly Flow) Basis of Design Veolia -

• HRT = Hydraulic Retention Time

• MMF = Maximum Monthly Flow

Page 68 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD The MBR Process Building will consist of the following architectural characteristics:

• 4-inch Brick veneer with CMU block bearing wall, with steel roof trusses, and stranding seam metal roof.

• FRP doors, windows, frames, etc., as required, with a new reinforced concrete slab.

• This building will be an enclosure for covering process equipment/blowers, chemical cleaning systems for

the membranes, and methanol chemical storage/dosing equipment.

6.3 Site Plans and Schematics Alternative 1 – SBR will include the post EQ tank expansion, which includes the volume of the existing post EQ and sludge holding tanks. Two additional SBR tanks, adjacent to the current ones, will be constructed.

Additionally, denitrification filters will be installed, and their respective Control Building will be built adjacent to the Filter and Blower Building. Finally, the sludge drying reed beds would be transformed to include the influent flow equalization tank, aerobic digesters, Dewatering Facility, and Covered Cake Storage Facility.

Alternative 2 – Conventional Activated Sludge and Alternative 3 – MBR Activated Sludge would see the existing SBR tanks converted into two (2) influent flow equalization tanks, while the middle tanks would be converted into two (2) aerobic digesters. The Dewatering Facility and Covered Cake Storage Facility will be constructed to the south of the influent screening, influent flow equalization tanks, and aerobic digesters. Across the road, where the

existing sludge drying reed beds are located, a 2 train 5-stage activated sludge process would be constructed.

At the end of the train, Alternative 2 will have secondary clarifiers, while Alternative 3 will have the MBR tanks and MBR Process Building, housing the blower and methanol storage and feed equipment. Similar to Alternative 1, Alternative 2 will have denitrification filters installed, and their respective Control Building will be built adjacent to the Filter and Blower Building.

All three alternatives will include replacement of the influent screening, and backup generator, which will all be constructed in the same relative location of the existing facilities, respectively. The Control and Lab Buildings will each be modified, as discussed in Sections 6.1.8, 6.1.9, and 6.1.10. Each site plan also includes reserved area for construction of a shellfish protection tank, if year-round stream discharge into the Corsica River is pursued in

the future.

Page 69 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.4 Environmental Impact Environmental impacts associated with each design alternative are quantified in Table 6.10 and summarized by

alternative below. Alternative 3 – MBR Activated Sludge would have the least environmental impacts compared to both Alternative 1 – SBR and Alternative 2 – Conventional Activated Sludge.

Table 6.10: Environmental Impacts by Design Alternative for Centreville WWTP Site Environmental Resource Alternative 1 (SQFT) Alternative 2 (SQFT) Alternative 3 (SQFT) Palustrine Emergent (PEM) Wetland 0 0 0 Palustrine Forested (PFO) Wetland 459 486 0 Perennial Stream 0 0 0 Wetland 25-ft Buffer 2,199 2,985 177 Forest Stands 1,733 5,598 178 FEMA Floodplain 29 22 0 Forest Interior Dwelling Bird (FIDS)

9,190 21,513 13,307 Habitat Tier 2 Catchment 55,137 49,184 47,259 Chesapeake Bay Critical Area 55,137 49,184 47,259 6.4.1 Alternative 1 – Expand the Sequencing Batch Reactor Alternative 1 – SBR would impact existing wetlands/wetland buffer, forest, the 100-year floodplain, all located in the northernmost portion of the LOD. There would be impacts to FIDS habitat across the northern, northeastern, and western portions of the LOD. There would also be impacts to the Gravel Run 1 Tier II (High Quality)

catchment and CBCA throughout the entire LOD. Alternative 1 would not impact any streams.

6.4.2 Alternative 2 – Conventional Activated Sludge Alternative 2 – Conventional Activated Sludge would impact existing wetlands/wetland buffer, forest located in the northernmost and westernmost portions of the LOD. This alternative would impact the 100-year floodplain located in the northernmost portion of the LOD. There would be impacts to the FIDS habitat throughout the northern and western portions of the LOD. There would also be impacts to the Gravel Run 1 Tier II (High Quality) catchment

and CBCA throughout the entire LOD. Alternative 2 would not impact any streams.

6.4.3 Alternative 3 – Membrane Bioreactor Alternative 3 – MBR Activated Sludge would impact existing wetland buffer in the northwestern portion of the LOD. There would be impacts to forests in the northernmost portion of the LOD and the FIDS habitat throughout the northern, northeastern, and western portions of the LOD. This alternative would also the Gravel Run 1 Tier II (High Quality) catchment and CBCA throughout the entire LOD. Alternative 3 would not impact streams or the

100-year floodplain.

6.5 Sustainability Considerations The WWTP upgrade and expansion will be designed to reduce its impact on the environment and to be resilient to future changes in the climate as indicated in this section.

Page 73 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.5.1 Water, Chemical and Energy Efficiency The existing WWTP utilizes potable water for all its water needs. The upgrade will include an onsite non-potable water system to utilize treated effluent for the process related water needs.

The treated effluent water quality will be sufficient to meet off-site Class III and IV reclaimed water requirements.

Potential future off site water reuse includes irrigation of the Queen Anne County recreational fields located adjacent to the Town.

In addition to the onsite water reuse, the potable water use onsite will be reduced through the replacement of the existing plumbing fixtures with low flow.

Energy efficiency will be considered for the selection of lighting and equipment for the project. Examples of improved energy efficiency include:

• The existing florescent tube and halogen lights will be replaced with LED lights. New lights will only be LED.

• All equipment will use high efficiency motors.

• The UV disinfection system will have the latest generation of UV intensity measurement and lamp controller.

• Pumps will have variable frequency drives (VFD) to operate at optimal speeds.

• New process blowers will be high efficiency turbo blowers.

• Dewatering equipment will consider slow speed, low energy demand type equipment.

The primary chemical consumptions include external carbon for denitrification and metal salt for phosphorus removal and are similar for all three alternatives. Alternative 3 has additional cost related to the use of acid and bleach for periodic membrane cleanings. Labor costs and electrical power costs are also slightly higher for Alternative 3 however differences are not significant. The major operating costs (maintenance, energy, chemical

and labor) are includedin Table 7.5.

6.5.2 Green Infrastructure The three alternatives will have similar opportunities for incorporating green infrastructure as deemed practical. As an example, the roof cover over the dewatered biosolids storage area will be designed to accommodate the future installation of solar PV cells. The solar PV cells will be connected to the utility electric grid to offset the electricity used by the WWTP. There may be other areas on the site that could accommodate additional solar PV cells.

6.5.3 Climate Related Considerations The upgrade and expansion of the WWTP is required to protect the receiving stream and the environment from wastewater that does not meet the discharge permit requirements. Without an expansion of the treatment capacity, the likelihood of future process upsets increases with the increase in influent flows stressing the capabilities of the existing system.

The new facilities will be constructed to protect them from a 100-year flood with 3 feet of additional protection provided. New structures will have a finished floor or top of wall of at least 3 ft above the 100-year flood elevation.

By selecting Alternative 3 – MBR Activated Sludge, the proposed facilities would have the smallest footprint of the alternatives considered. Therefore, the facilities would have a smaller impact to the site and can be located to reduce their impact on environmentally important features such as the wetlands and forested areas.

Page 74 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 6.6 Cost Estimates A conceptual cost estimate was developed for each of the three treatment alternatives that are being considered.

The cost estimates were developed using preliminary equipment supplier quotations based on the design concepts described in this preliminary engineering report. The cost estimate does not include expansion of the effluent discharge, such as the cost of extending the outfall into the Corsica River or the cost to acquire and spray discharge to additional irrigation sites.

The cost estimates for each of the treatment alternatives were developed using the expertise and experience of the WRA engineers. The cost estimates presented represent WRA’s best engineering judgement and assumes that competitive bids are received. However, the unpredictability of the current market should be taken into consideration when the project goes to bid. The estimates were prepared in accordance with AACE Class 4

Budgetary (planning-level) construction cost requirements. All costs are presented in 2023 dollars and will need to be indexed using the annual inflation rate. Contingency cost, an allowance that reflects the uncertainty associated with a construction cost opinion based on a “predesign” study of the indicated facilities, is included as a 30% markup in the estimate. Additionally, an escalation markup of 4% per year is also included in the estimate.

The conceptual cost estimates for each alternative are presented in Table 6.11. Refer to Appendix A for detailed breakdown.

Page 75 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.11: Conceptual Construction Cost Estimates for Treatment Alternatives Alternative 2:

Alternative 3: MBR Alternative 1: SBR Conventional Activated Activated Sludge Sludge Base Facilities Interior Demolition (Lab, Control, and Filter and Blower Buildings) $ 95,000 $ 95,000 $ 95,000 Influent Screening Expansion $ 825,000 $ 825,000 $ 825,000 Methanol Facility $ 618,000 $ 618,000 $ 618,000 Non-Potable Water System $ 54,000 $ 54,000 $ 54,000 Dewatering Facility $ 2,413,000 $ 2,413,000 $ 2,413,000

Covered Cake Storage Facility $ 835,000 $ 835,000 $ 835,000 Lab Building Refurbishment $ 139,000 $ 139,000 $ 139,000 Control Building Refurbishment $ 130,000 $ 130,000 $ 130,000 Filter and Blower Building Refurbishment $ 348,000 $ 348,000 $ 348,000 Base Subtotal Cost $ 5,457,000 $ 5,457,000 $ 5,457,000 Facilities for ENR Alternatives Influent Flow EQ Tank(s), Aerated, with Pumping $ 2,054,000 $ 2,019,000 $ 2,019,000

Existing Tank Modifications $ 214,000 $ 643,000 $ 643,000 Clarifier Tanks, Equipment, and RAS Pumps - $ 4,749,000 - Denitrification Filter Tanks, Equipment and Controls $ 3,112,000 $ 3,112,000 - Miscellaneous Process Piping and Equipment $ 157,000 $ 235,000 $ 784,000 Additional SBR Tanks, Equipment and Controls $ 3,564,000 - - Activated Sludge Equipment - $ 1,012,000 - MBR Process Equipment and Controls, including MBR Process Building - - $ 5,789,000

Post EQ Tank and Equipment $ 78,000 - - UV Disinfection System $ 642,000 $ 642,000 $ 642,000 Aerobic Digester Tank and Equipment $ 1,427,000 $ 78,000 $ 78,000 Alternative Subtotal Cost $ 11,248,000 $ 12,490,000 $ 9,955,000 Alternative Plus Base – Subtotal Construction Cost $ 16,705,000 $ 17,947,000 $ 15,412,000 Electrical $ 2,517,000 $ 2,722,000 $ 4,169,000 Site Civil, including Yard Piping and Demolition (15% Alternative + Base) $ 2,506,000 $ 2,692,000 $ 2,312,000

Site SCADA (5% Alternative + Base) $ 835,000 $ 897,000 $ 771,000 Subtotal $ 22,563,000 $ 24,258,000 $ 22,664,000 Contingency (30%) $ 6,769,000 $ 7,278,000 $ 6,799,000 Escalation to December 2026 (4%/year) $ 3,662,000 $ 3,938,000 $ 3,678,000 Grand Total Construction Cost $ 32,994,000 $ 35,474,000 $ 33,141,000 Page 76 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

6.7 Design Criteria The influent basis of design flows and loads for the upgrade and expansion are included in Table 6.12.

Table 6.12: Influent Basis of Design Annual Max Max Peak Start Up Parameter Units Average Month Day Inst. Min Day Flow MGD 1.0 1.2 2.4 3.2 0.2 Wastewater Degrees 20 12 Temperature C mg/l 130 156 Biochemical Oxygen Demand lbs/day 1,084 1,561 mg/l 145 174 Total Suspended Solids lbs/day 1,209 1,741 mg/l 35 42 Total Kjeldahl Nitrogen lbs/day 292 420 mg/l 8 8 Total Phosphorus lbs/day 67 80 The flow peaking factors were developed based on the MDE Design Guidelines for Wastewater Facilities, with the

exception of the monthly peaking factor. The design uses a peaking factor of 1.2, and the MDE design guidelines recommend a peaking factor of 1.6 for a 1 MGD facility. The upgrade and expansion of the Centreville WWTP is designed to provide full treatment during the maximum month flows and loads, during cold weather conditions, with one treatment train offline. Considering that Centreville will only have two MBR trains, sizing one train to treat

the maximum monthly flow and loads at the MDE recommended monthly flow peaking factor of 1.6 would oversize the facilities for start-up conditions, and thereby requiring only one train to be operated at a time to be efficient. During final design a maximum monthly flow peaking factor of 1.3 will be considered and determined if it would represent a de minimis increase in construction costs and have a small impact on the operability of the

facility during start-up. If so, the design basis will be adjusted.

The influent total suspended solids (TSS) and biological oxygen demand (BOD) were sampled and analyzed in 2017 and again in 2023 as presented in Appendix C. The TSS measurements were highly variable, with a standard deviation nearly as large as the average. In addition, the wastewater biological and chemical computer modeling software being used, BioWin by EnviroSim, requires the TSS concentration to be higher than the BOD

concentration to allow for valid calculations. Therefore, the TSS concentrations were adjusted to be in line with the BOD values.

The design basis influent total phosphorus concentration selected utilizes the maximum daily composite sample from the 2017 and 2023 sampling and analysis. Again, the limited samples that were taken and analyzed resulted in a large distribution of values. The chemical dosing system will be designed to meet maximum month influent loading. Using a conservative value for phosphorus concentration will allow the system to reliably meet the

Page 77 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD relatively low ENR effluent phosphorus concentration of 0.15 mg/L as proposed by MDE if year-round stream discharge is selected.

The design effluent quality basis of design for the project are summarized in Table 6.13. Each alternative must meet the effluent basis of design.

Table 6.13: Effluent Basis of Design Parameter Units Annual Monthly Average Max Month Biochemical Oxygen mg/l <10 <10 Demand Turbidity1 NTU <2 <5 any time Total Suspended Solids mg/l <10 <10 Total Nitrogen mg/l <3 <3 Total Phosphorus2 mg/l <0.15 <0.15 MPN / 100 mL E. Coli E. Coli1 1 23 Monthly Median 1 Class IV Reclaimed Water Requirements, 2 Requirement with relocated outfall to Corsica River 6.8 Land Requirements

The WWTP upgrade and expansion will be constructed on developed land owned by the Town. The land disturbance at the WWTP will vary depending on which alternative is selected for the upgrade. Alternative 1 (SBR) would require the largest footprint at the WWTP to construct, while Alternative 3 (MBR) would require the smallest footprint. Refer to Section 6.3 for proposed site plans for each of the three alternatives.

Future expansion of the spray irrigation system would require at least 300 acres of suitable land located near the Town. The identification, testing, and development of the field will be considered separately from the WWTP upgrade.

6.9 Potential Construction Issues The construction of the three alternatives will have potential construction issues that need to be identified, the risks understood, and mitigation plans developed. Based on experience and knowledge of the site, an initial list of specific construction related issues and methods to mitigate the risk have been developed as summarized in Table 6.14.

In order to maintain plant operations during construction, both existing SBRs are required to remain online until the selected treatment process is constructed and put into service. For Alternative 2 – Conventional Activated Sludge and Alternative 3 – MBR Activated Sludge, this requires the 2 train 5-stage activated sludge basins to be constructed and put into service before either of the SBR tanks are converted into influent flow equalization tanks.

The proposed site layouts for each of the three alternatives, described in Section 6.3, allow for maintenance of plant operations during construction.

Page 78 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 6.14: Summary of Potential Construction Issues Issue Risk Planned Mitigation Methods Encountering Dewatering excavation Plan for thorough soil borings and geotechnical groundwater during expense investigations early during design excavations Encountering Review all available information.

unidentified Change in scope during underground piping and construction During design conduct subsurface investigation and structures test pitting where there are potential obstructions Realistically estimate delivery times based on Product and equipment Delay in construction estimates from named manufacturers and delivery longer than schedule experience with other projects and keep in contact expected

with key manufacturers during construction Integration of Insufficient process data Complete process and instrumentation diagrams, manufacturer supplied relayed to the SCADA Input/Output lists and control descriptions will be control panels with the from the manufacturer’s included in the Contract Documents plant SCADA control panels Automation is too Conduct workshops with operations to custom tailor

Level of automation that complex for operations the control system and the level of automation with operations can maintain to troubleshoot and the needs and skills of operations maintain Contract Documents will include a 30 day testing period of the complete treatment plant with a Assessing the treatment requirement to operate the plant with equipment and Treatment process process under design treatment trains offline to simulate design

testing conditions conditions. Testing conditions, sampling and requirements for the system passing the testing will be included.

The definition of substantial completion for individual In complex upgrade facilities and major equipment, and the projects some treatment Turn over of treatment responsibilities for the Owner and Contractor facilities will be brought facilities between facility substantial completion and final online before substantial completion will be clearly defined in the completion specifications.

The design phase will discover additional potential construction issues and where practical the Contract Documents will identify the area the Installing Contractor should be aware of.

Construction risks specific to Alternative 1 – SBRs include the deep structure construction of the SBRs in close proximity to the adjacent residences. Additionally Alternative 1 has the largest overall disturbed area, resulting in the greatest risk to encountering unknown obstructions. Therefore Alternative 1 has the largest risks during construction.

Construction risks associated with Alternative 2 – Conventional Activated Sludge include a large area of disturbance and the most number of new structures. One advantage of Alternative 2 to Alternative 1, and Alternative 2 avoids the deep construction adjacent to residences.

Construction risks associated with Alternative 3 – MBR are less than either of the two other options, as it avoids deep construction adjacent to residences, it also represents the fewest number of structures and has the smallest disturbance footprint.

Page 79 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 7 Alternative Evaluation 7.1 Effluent Water Quality Comparison Each of the three alternatives are capable of meeting the treatment and capacity goals for this project. To verify this, the expected secondary effluent water quality of each alternative was evaluated by modeling each of the three treatment alternatives using BioWin software. Each treatment alternative was modeled under average flow

conditions and maximum monthly (simulating wet weather) flow conditions.

Table 7.1 shows the different influent conditions that were used for modeling average conditions versus maximum monthly conditions for each alternative. These influent conditions are based on composite influent sampling data of the WWTP conducted in September/October 2017 and in March 2023, which is included in Appendix C. Note that influent sampling data was limited since it is not conducted on a regular basis.

Table 7.1: BioWin® Model Influent Conditions Biochemical Volatile Total Total Kjeldahl Oxygen Flow Temperature Suspended Suspended Nitrogen Condition Demand Solids (VSS) Solids (TSS) (TKN)

(BOD)

(MGD) (Deg C) (mg/L) (mg/L) (mg/L) (mg/L) Average 1.0 20 130 116 145 35 Maximum 1.2 12 156 139 174 42 Monthly Additional influent conditions were assumed in the model which did not change between average and maximum monthly model runs. These conditions include:

• Total Phosphorus = 8.0 mg/L

• Total Sulfur = 10 mg/L

• Nitrate = 0 mg/L

• pH = 7.3

• Alkalinity = 6.0 mmol/L

As stated in Section 2.3.1, the treatment quality goals for ENR include a TN concentration below 3.0 mg/L and a TP concentration below 0.3 mg/L. The reduction in TP at Centreville WWTP will depend on upgrades to the existing chemical dosing system and amount of PACl added to precipitate phosphorus. PACl chemical dosing was not modeled in BioWin. Therefore, this modeling study focused on comparing TN reduction in the biological

treatment process for each of the three treatment alternatives.

Table 7.2 lists the biological treatment quality parameters that were monitored in the secondary effluent in BioWin, as well as the target concentrations for each of the three alternatives in order to meet the effluent quality goals of this project. The parameters that were monitored include concentrations of MLSS, cBOD, TSS, ammonia, filtered TKN, and nitrate + nitrite.

Page 80 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 7.2: Target Secondary Effluent Water Quality Parameters Biological Treatment Alternative 1 (SBR) and Alternative 2 Alternative 3 (MBR Activated Sludge) Parameter (Conventional Activated Sludge) MLSS <= 4,000 mg/L <= 8,000 mg/L cBOD <= 30 mg/L <= 2 mg/L TSS <= 20 mg/L Non-detect Ammonia < 1.0 mg/L < 1.0 mg/L

Filtered TKN < 2.0 mg/L < 2.0 mg/L Nitrate + Nitrite < 8.0 mg/L < 1.0 mg/L As shown in Table 7.2, Alternatives 1 and 2 have the same target effluent quality concentrations with respect to nitrate (/nitrite) and rely on the downstream denitrification filters to complete the nitrogen removal, although Alternative 2 can also incorporate methanol addition in the post-anoxic zone for enhanced nitrogen removal and

use the tertiary filters for final solids removal only. For Alternative 3 all nitrogen removal is within the MBR process tankage as there is no additional downstream removal process, and is facilitated by methanol addition within the MBR secondary anoxic zone to reduce nitrate + nitrite concentrations below 1 mg/L.

All three alternatives require ammonia concentrations to be below 1 mg/L. MBRs can typically operate at higher MLSS concentrations compared to conventional activated sludge clarifiers, which is why Alternative 3 has a higher allowable MLSS concentration.

Tables 7.3 and 7.4 show the secondary effluent water quality results from modeling at both average and maximum monthly conditions.

Table 7.3: Secondary Effluent Water Quality BioWin Modeling Results – Average Conditions Biological Alternative 2:

Alternative 1: SBR Alternative 3: MBR Condition Treatment Units Conventional Expansion Activated Sludge(1) Parameter Activated Sludge Flow MGD 1.0 1.0 1.0 MLSS mg/L 3,600 2,500 5,100 cBOD mg/L 6.0 2.4 1.0 TSS mg/L 20 9 0 Average Ammonia mg/L 0.30 0.12 0.06 Filtered TKN mg/L 1.3 1.4 1.2 Nitrate mg/L 2.9 4.0 0.08 Nitrite mg/L 0.05 0.03 0.01 Total Nitrogen mg/L 4.6 5.6 1.4

(1) – Note that Alternative 3 (MBR Activated Sludge) modeling includes 75 gpd of methanol addition in the

postanoxic zone.

Page 81 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 7.4: Secondary Effluent Water Quality BioWin Modeling Results – Maximum Monthly Conditions Biological Alternative 2:

Alternative 1: SBR Alternative 3: MBR Condition Treatment Units Conventional Expansion Activated Sludge(1) Parameter Activated Sludge Flow MGD 1.2 1.2 1.2 MLSS mg/L 3,800 3,600 7,500 cBOD mg/L 10 3.5 0.9 TSS mg/L 20 14 0 Maximum Ammonia mg/L 0.40 0.30 0.17 Monthly Filtered TKN mg/L 1.5 1.7 1.5 Nitrate mg/L 1.4 5.2 0.70 Nitrite mg/L 0.8 0.1 0.04 Total Nitrogen mg/L 4.1 7.3 2.4

(1) – Note that Alternative 3 (MBR Activated Sludge) modeling includes 75 gpd of methanol addition in the

postanoxic zone.

The secondary effluent quality of all three alternatives meets all of the target quality parameters listed in Table 7.2. The BioWin modeling results for filtered TKN concentrations are below 2 mg/L; however, the historical average TKN concentrations from 2014-2022, as listed in Section 4.4, are below 1 mg/L. It is assumed that BioWin is not properly accounting for the biodegradable portion of TKN, which is why filtered TKN concentrations

are reporting unusually high in the models. In conclusion, BioWin modeling of each of the three treatment alternatives confirms that each alternative is capable of meeting the treatment and capacity goals for this project.

7.2 Life Cycle Cost Analysis A life cycle cost analysis was performed on the three alternatives. A life cycle cost analysis combines the initial capital cost with the net present value of the operating costs across the expected life of the project into a present worth total. The life cycle cost analysis provides a more complete picture of the costs of the project than just the capital cost.

For the life cycle cost analysis, the electrical loads for the major equipment are multiplied by the percentage of time per year the equipment is expected to be running. Equipment with variable speed drives and variable loads are calculated using the expected annual average load.

Labor for each alternative was compared to the existing cost of labor for the current WWTP and extrapolated to consider the increased complexity of the upgrade as well as the increased size of the plant to treat the expanded flows.

The chemical costs indicated in Table 7.5 under ‘Annual Chemical Costs’ are the estimated costs of methanol to drive the denitrification process and the addition of PACl to precipitate phosphorus. The design average influent nitrogen and phosphorus and the goals for effluent nitrogen and phosphorus concentrations are used in the calculations at an annual average influent flow of 1.0 MGD.

As noted in the Table 7.5 footnote, the membrane cleaning chemical costs are included in the ‘Annual Maintenance/Repairs Costs’ for the Alternative 3 – MBR Activated Sludge. The ‘Annual Maintenance/Repair Costs’ also includes the annual contribution to replacement of the membranes every ten years.

For the life cycle cost analysis the project is assumed to have no salvage value at the end of the 20 years.

Page 82 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 7.5: Life Cycle Cost Analysis Alternative 2 – Alternative 1 – SBR Alternative 3 – MBR Conventional Activated Expansion Activated Sludge Sludge WWTP Capital Cost $32,994,000 $35,474,000 $33,141,000 Operating Cost Annual Maintenance/Repair $133,076 $164,841 $226,647 Costs(1) Annual Electric Cost $ 55,157 $77,528 $84,877

Annual Burdened Labor $384,800 $395,200 $499,200 Annual Chemical Costs $336,886 $336,886 $336,886 Operating Cost Subtotal $909,919 $974,455 $1,147,609 Real Discount Rate(2) 2% 2% 2% Project Life, years 20 20 20 Operating Cost Present Value $14,880,000 $15,930,000 $18,770,000 Present Worth $47,874,000 $51,404,000 $51,911,000

(1) Maintenance estimated at 2% of equipment cost for Alternatives 1 and 2 and 2.5% for Alternative 3 to

account for membrane replacement and cleaning chemicals

(2) December 2022 OMB Circular No. A-94

The life cycle cost analysis results in the present worth ranging from approximately $48 million for Alternative 1 up to $52 million for Alternative 3. The results are within 8% of each other. Considering the variability in estimating construction and operating costs, the three alternatives are similar in life cycle costs.

7.3 Non-Monetary Evaluation Life cycle costs include items of each alternative that have a dollar value. The value of the project will also be influenced by factors that do not have a direct cost measure. The following criteria for the non-monetary evaluation have been defined based on feedback from the Town of Centreville

• Leverages operators experience

• Operational simplicity

• Ease of maintenance

• Public acceptance

• Compatibility with water reuse

• Ability to evolve with future technologies

• Ability to upgrade treatment process in the future

• Available site space for future improvements

The non-monetary evaluation criteria are categorized and weighted as described below.

Leverages Operators Experience Operators currently at the Centreville WWTP have experience with operating the existing two-tank SBR system. This criterion evaluates the complexity in training operators for each of the three treatment alternatives. This criterion was assigned a weighting factor of 5%, due to significantly different levels of training that would be required for each of the three alternatives.

Operational Simplicity Each of the three alternatives will have different day-to-day involvement for operators and will require different levels of attention to maintain operation. Because some of the alternatives are more complicated to operate, this criterion was assigned a weighting factor of 5%.

Page 83 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Ease of Maintenance The equipment for each treatment alternative must be accessible for maintenance once it is placed into service. Equipment must also be reliable and have a low likelihood of experiencing upsets and discharging unacceptable effluent, so maintenance may be kept at a minimum. This criterion considers

each alternative’s reliability, how often the equipment for each alternative will require servicing, as well as the availability of replacement parts and how complex the equipment is to maintain. This criterion has been assigned a weighting factor of 10%.

Public Acceptance This category considers the public view and acceptance of the three treatment alternatives. The upgrade and expansion of the Centreville WWTP has been presented to various public groups and stakeholders within the Centreville area, and the public perception and feedback received from these groups is considered in this criterion. Alternatives that received more positive feedback will be given a higher score.

This criterion has been assigned a weighting factor of 10%.

Compatibility with Water Reuse The Town of Centreville plans for future potable water reuse using the WWTP effluent. This criterion evaluates how each treatment alternative positions the Town to move towards potable water reuse in the future. This includes how much expansion to the treatment process will be required in the future to meet the effluent quality levels required for potable water reuse. This criterion has been assigned a weighting

factor of 10%.

Ability to Evolve with Future Technologies It is important to the Town that the Centreville WWTP is positioned to incorporate future treatment technologies and remain on the forefront for wastewater treatment. This category considered how flexible each treatment alternative is for incorporating future technologies. Because this criterion has a high importance to the Town, it has been assigned a weighting factor of 20%.

Ability to Upgrade Treatment Process in the Future Federal and state regulatory agencies may establish more stringent effluent quality requirements in the future—therefore, this category considers how each treatment alternative can be upgraded in the future to meet higher effluent quality. This criterion has a high importance to the Town and therefore has been assigned a weighting factor of 20%.

Available Site Space for Future Improvements Future expansion and development in the Town of Centreville will require additional expansion of the WWTP beyond the planned 1.0 MGD capacity. This category considers how much site space will be available after construction of each treatment alternative. It is desired to maintain as much site space as possible for future expansion efforts. Because of this, this criterion has been assigned a weighting factor

of 20%.

Each of the evaluation criteria noted above have been weighted to reflect their relative importance to the construction and operation of the treatment process. The weighting factors were discussed with the Town staff and represent the consensus opinion. Each alternative was assigned a score based on a scale of 1 to 10, with 1 being the lowest or least desirable and 10 being the highest or most desirable for a given criterion. The total score

for each category was then determined by multiplying the individual criteria scores by the assigned weight, and then summing up the weighted scores. Table 7.6 presents the final criteria ranking tabulation.

Page 84 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 7.6: Non-Monetary Evaluation of Treatment Alternatives Weight % 5 5 10 10 10 20 20 20 Ability to Upgrade Leverages Operators Compatibility with Ability to Evolve with Available Site Space for Total Operational Simplicity Ease of Maintenance Public Acceptance Treatment Process in the Rank

Experience Water Reuse Future Technologies Future Improvements Score Future Score Comments Score Comments Score Comments Score Comments Score Comments Score Comments Score Comments Score Comments The SBR process is The SBR tanks This alternative Operators are The SBR viewed are adaptable and requires the most highly familiar The SBR The SBR process will favorably by the can be modified to amount of site Requires

with the existing process has a process requires provide Alternative 1: public, but is accommodate space. It will be the relatively high 10 SBR technology, 10 relatively low 10 minimal 8 10 effluent quality 7 4 4 680 3 SBR Expansion seen as an other most challenging amount of site which is complexity for maintenance of suitable for older, technologies, such to further upgrade disturbance.

currently used at operators. equipment. future water conventional as aerobic the future the WWTP. reuse.

treatment granular sludge. treatment capacity.

process.

This alternative Operators will be The activated requires a able to use sludge process The activated The activated The activated moderate amount knowledge of the The activated is viewed sludge process sludge basins are Alternative 2: sludge process of site space. Requires existing SBR sludge process favorably by the will provide adaptable and can Conventional requires There will be relatively low 8 process to learn 6 is moderately 8 8 public, but is 10 effluent quality 7 be modified to 6 6 710 2

Activated relatively low space to construct amount of site the new complex for also an older suitable for accommodate Sludge maintenance additional disturbance.

conventional operators. conventional future water future equipment. activated sludge activated sludge treatment reuse. technologies.

basins for future process. process.

upgrade.

The MBR is a The MBR newer treatment process technology on the The MBR received the forefront of This alternative process is The MBR most positive The MBR wastewater minimizes the The MBR significantly process has feedback from process will treatment. It amount of site process requires Alternative 3: different than the highly complex public groups. It provide removes the most space required. Requires least

significant MBR Activated 1 existing SBR 1 equipment that 1 10 is one of the 10 effluent quality 9 solids of the three 10 There will be 10 amount of site 800 1 maintenance of Sludge process and will requires a lot of newer, suitable for alternatives, space to construct disturbance.

complex require operational advanced future water providing additional MBR equipment.

considerable attention. technologies reuse. marginally better tanks for future training. that public effluent quality to upgrade.

groups are most be used in a future excited about. potable water reuse system.

Page 85 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Based on the results of the evaluation, of the three treatment alternatives evaluated, Alternative 3 – MBR Activated Sludge received the highest score based on the criteria listed in this section.

Before recommending Alternative 3 – MBR Activated Sludge, one non-monetary consideration that is specific to MBRs was also considered, and that is the design of MBR systems from different vendors varies widely. The MBR is purchased as an integrated system of equipment and controls, and there is no standardization among MBR vendors. The equipment required, physical layout, operational characteristics and control can be very

different for each vendor’s system.

To avoid expensive re-design during construction to accommodate the specifics of the provided MBR system, the Town will include a competitive pre-selection of MBR system and vendor during the final design of the project. By developing a request for proposals (RFP) for the MBR system between the 30% and 60% design submittals, the design can be tailored to the pre-selected system. This also shortens the time for development of shop drawings

after the notice to proceed for construction, so key long lead items can be purchased in time to avoid the construction schedule critical path.

The design engineer and the Town will also consider pre-purchasing major equipment that could greatly impact the overall construction duration. One item included in each alternative scope that remain with an excessively long lead time is the back-up generator. Fortunately, the back up generator does not impact the installation and start up of any of the treatment facilities. So, if the generator could be installed before the scheduled substantial

completion, it would not impact the overall construction duration. It is anticipated that the generator delivery could be 18 months, which would not impact the overall construction duration.

Having addressed these Alternative 3 – MBR Activated Sludge risks, and as a result of the life cycle cost analysis and the non-monetary evaluation, Alternative 3 – MBR Activated Sludge is the recommended treatment upgrade for the Centreville WWTP. This alternative will be further developed during detailed design.

Page 86 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 8 Recommended Upgrades and Expansion 8.1 Preliminary Project Design A summary of the project scope for the expansion and upgrade of the Centreville WWTP to an MBR activated sludge treatment process is detailed in this section. Table 8.1 lists the preliminary project design and facility upgrades that are required for the recommended alternative.

Table 8.1: Preliminary Project Design – Alt 3 MBR Activated Sludge Facility Description Replace the existing mechanical screen with a bar rack rated at 4.0 MGD (peak Influent Screening hydraulic flow) and install new center feed fine screens down stream of bar rack.

Convert the existing SBR process tanks to two (2) 500,000-gallon working capacity Influent Flow Equalization each influent flow EQ tanks with surface aerator/mixers. Submersible pumps will Tank pump flow from the EQ tank to the MBRs.

Install 2 train, 5-stage activated sludge process with membranes to separate solids from treated effluent. Fine bubble diffusers will be installed to incorporate air from proposed high efficiency blowers. Anoxic and swing zones will be agitated with submersible mixers. Permeate pumps will draw effluent through membranes. Low MBR Process head propeller pumps for internal recycle and return activated sludge will be

installed. Waste sludge pumps will pull mixed liquor from the reactors and discharge into the aerobic digesters. Chemical cleaning facilities will be provided to clean the membranes.

Provide a double contained PACl tank located in the Filter and Blower Building Chemical Dosing with a minimum of 30 days of storage and dosing system. Provide methanol storage with a minimum of 30 days of storage and dosing facility.

Install two (2) in-line low pressure high output (LPHO) UV disinfection units to UV Disinfection replace existing.

To be further evaluated:

• Additional spray irrigation disposal,

Effluent Disposal

• Relocate outfall and expand stream discharge to year-round, and

• Planning for future beneficial water reuse.

Install a non-potable water system that draws from the UV effluent to a buffer tank Non-potable Plant Water in the Filter and Blower Building. Install pumps to distribute non-potable water System supply from the buffer tank throughout the WWTP.

Retrofit the existing post EQ and sludge holding tanks to two (2) aerobic digesters Aerobic Digesters with ability to thicken solids and decant liquid back to treatment process.

Biosolids Dewatering Install new biosolids handling building for dewatering process. New covered System sludge cake storage area for Class B biosolids.

Provide enhanced process controls at separate process areas with routine Plant Control System and functions or complex control loops with centralized monitoring and control SCADA workstation for operator interface. Provide capabilities to provide hub for Town wide SCADA system of utilities.

Administration/Laboratory Reconfigure the Administration/Laboratory Building to better utilize the space for Space the laboratory uses and provide dedicated space for locker rooms and offices.

Page 87 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 8.2 Permit Requirements Impacts to wetlands and other WOTUS would require Section 404 authorization from the U.S. Army Corps of Engineers (USACE) for the discharge of dredge or fill material. Impacts to waterways, 100-year floodplains, nontidal wetlands, 25-foot nontidal wetland buffers would require a Maryland Nontidal Wetlands and Waterways

Permit. Additionally, a Section 401 Water Quality Certificate from MDE is required for any impacts to waterways or wetlands requiring a USACE Section 404 authorization. Projects with the potential to impact Tier II waters are subject to MDE’s Tier II Antidegradation Review. Early coordination with MDE will be initiated during the permitting process to determine whether additional avoidance measures and best management practices (BMPs)

are required. Impacts to forest, trees, and FIDS habitat within the CBCA would require coordination with the Chesapeake Bay Critical Area Commission (CAC) and/or the Queen Anne’s County Critical Area Program.

Table 8.2 summarizes the expected permits that will need to be obtained during the design phase of the project.

Additional environmental permits will be identified during design.

Table 8.2: Permit Requirements Permitting Agency Permit Maryland Department of the Sewerage Construction Permit Environment (MDE) Maryland Department of the Modification to NPDES Surface Water Environment (MDE) Discharge Permit Maryland Department of the NPDES Permit for Stormwater Environment (MDE) Discharge During Construction Activities Sediment and Erosion Control Plan Queen Anne’s County Permit

Queen Anne’s County Stormwater Management Permit 8.3 Sustainability Considerations The WWTP upgrade and expansion to an MBR treatment process will be designed to reduce its impact on the environment and to be resilient to future changes in the climate as indicated in this section.

8.3.1 Water and Energy Efficiency As described in Sections 6.1.7 and 6.5.1, a non-potable water system will be installed at the Centreville WWTP to promote water efficiency by reducing the onsite potable water demand and reusing treated plant effluent. The treated effluent water quality will be sufficient to meet off-site Class III and IV reclaimed water requirements. New developments will be encouraged to connect into the reclaimed water for irrigation of common spaces.

Energy efficiency will also be at the forefront for the selection of lighting and equipment for the project. Examples of improved energy efficiency include:

• The existing florescent tube and halogen lights will be replaced with LED lights. New lights will only be LED.

• All equipment will use high efficiency motors.

• The UV disinfection system will have the latest generation of UV intensity measurement and lamp controller.

• Pumps will have variable frequency drives (VFD) to operate at optimal speeds.

• New process blowers will be high efficiency turbo blowers.

Page 88 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

• Dewatering equipment will only consider slow speed, low energy demand type equipment.

8.3.2 Green Infrastructure As described in Section 6.5.2, the selected treatment Alternative 3 will incorporate green infrastructure at a reasonable cost. The canopy over the dewatering cake storage area will be designed to accommodate the future installation of solar cells. The solar cells will be connected to the utility electric grid to offset the electricity used by the WWTP.

8.3.3 Climate Related Considerations As described in Section 6.5.3, the upgrade and expansion of the WWTP is required to protect the receiving stream and the environment from wastewater that does not meet the discharge permit requirements. Without an expansion of the treatment capacity, the likelihood of future process upsets increases with the increase in influent flows stressing the capabilities of the existing system.

The new facilities will be constructed to protect them from a 100-year flood with 3 feet of additional protection provided. New structures will have a finished floor or top of wall of at least 3 ft above the 100-year flood elevation.

With the recommended treatment Alternative 3 – MBR Activated Sludge, the proposed facilities will have the smallest footprint of the alternatives considered and can be located to reduce the impact on environmental features such as wetlands and forested areas.

Additionally, expansion of the sludge treatment and handling facilities will result in Class B biosolids. This could potentially allow for land application of the dewatered biosolids, which is a more solution to minimizing landfill disposal.

8.4 Construction Cost Estimate A budgetary cost estimate of construction for the recommended treatment alternative (Alternative 3 – MBR Activated Sludge) is included below. The cost estimate was developed using preliminary equipment supplier quotations based on the design criteria and unit costs for structures and ancillary construction. All three treatment alternatives were analyzed for construction and life cycle cost (see Sections 6.6 and 7.2), but this section will

focus on the construction cost estimate of the recommended Alternative 3.

The estimates were prepared in accordance with AACE Class 4 Budgetary (planning-level) construction cost requirements. All costs are presented in 2023 dollars and will need to be indexed using the annual inflation rate.

Contingency cost, an allowance that reflects the uncertainty associated with a construction cost opinion based on a planning level stage of the facilities, is included as a 30% markup in the estimate. Additionally, an escalation markup of 4% per year is also included in the estimate.

The estimated total construction cost for Alternative 3 – MBR Activated Sludge is summarized in Table 8.3.

Additional cost breakdowns for Alternative 3 – MBR Activated Sludge are included in Appendix A.

Page 89 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 8.3: Scope and Construction Cost Estimate – Alternative 3 (MBR Activated Sludge) Item No. Category Cost 1 Interior Demolition (Lab, Control, and Filter and Blower Buildings) $95,000 2 Influent Screening Expansion $825,000 3 Converting Influent Flow Equalization Tanks, Aerated, with Pumping $2,019,000

4 Methanol Facility $618,000 5 UV Disinfection System $642,000 6 Non-Potable Water System $54,000 7 Dewatering Facility $2,413,000 8 Covered Cake Storage Facility $835,000 9 Lab, Control, and Filter and Blower Buildings Refurbishments $617,000 10 Existing Tank Modifications $643,000 11 Miscellaneous Process Piping and Equipment $784,000 12 MBR Process Building, MBR Equipment and Controls $5,789,000

13 Aerobic Digester Tank and Equipment $78,000 14 Electrical $4,169,000 15 Site Civil, including Yard Piping and Demolition (15% Items 1-12) $2,312,000 16 Site SCADA (5% Items 1-12) $771,000 Subtotal $22,664,000 Design Contingency (30% of Subtotal) $6,799,000 Escalation to December 2026 (4%/year) $3,678,000 Total $33,141,000 Total (Low Range -20%) $26,513,000 Total (High Range +50%) $49,712,000 8.5 Annual Operating Budget

8.5.1 Income The Town projects income for the sewer system primarily from ongoing sewer service fees with some new connection fees expected. Table 8.4 summarizes the currently projected annual income for the sewer system for the next five fiscal years.

Page 90 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Table 8.4: Sewer System Income Fiscal Year Projected Annual Income

FY24 $1,531,427

FY25 $1,607,998

FY26 $1,704,478

FY27 $1,826,791

FY28 $1,972,694

8.5.2 Annual O&M Costs The primary operating and maintenance costs after Alternative 3 is implemented are summarized in Table 7.5, with Alternative 3 repeated in Table 8.5 for ease of reference.

Table 8.5: Annual Sewer System O&M Costs Alternative 3 – MBR Activated Sludge Annual Costs Maintenance/Repair Costs(1) $226,647 Electric Cost $ 84,877 Burdened Labor $499,200 Chemical Costs $336,886 Total Operating and Maintenance $1,147,610 Costs

(1) - Maintenance is estimated at 2.5% of equipment cost for

Alternative 3 to account for membrane replacement and cleaning chemicals.

8.5.3 Debt Repayments The Town’s existing debt is being serviced from the annual budget. Additional debt will primarily be serviced through anticipated connection fees and additional sewer service fees from the planned and anticipated developments within the current town boundary and by the annexation of adjacent development.

8.5.4 Reserves The Town maintains a healthy reserve fund. As the Town grows, the reserve fund will also be increased to keep pace with the increased operating and maintenance costs of the expanded treatment plant.

8.6 Project Implementation Schedule A preliminary construction schedule has been developed for the scope of work. The task durations for each of the facility upgrades detailed in this report are included in Figure 8.1.

Page 91 ID Task Name Duration Start Finish 2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 1 Centreville WWTP ENR 1655 days Mon Mon Upgrade and Expansion 3/20/23 7/23/29 2 PER Development 255 days Mon 3/20/23Fri 3/8/24 3 Start PER Update 0 days Mon 3/20/23Mon 3/20/23 3/20 4 Advertise for M/WBE 4 wks Mon 3/27/23Fri 4/21/23

5 Town Assembles 4 wks Mon 3/27/23Fri 4/21/23 Requested Information 6 Develop ENR PER 2 wks Mon 4/24/23Fri 5/5/23 Amendment 7 Town Review PER 2 wks Mon 5/8/23 Fri 5/19/23 Amendment 8 Sub Agreements 2 wks Mon 5/22/23Fri 6/2/23 9 Develop Draft PER 4 wks Mon 6/5/23 Fri 6/30/23 10 Topo Survey 4 wks Mon 6/5/23 Fri 6/30/23 11 Develop Alternatives 16 wks Mon 3/20/23Fri 7/7/23 12 Subconsultant Field Work8 wks Mon 5/22/23Fri 7/14/23

13 Develop PER 22 wks Mon 7/17/23Fri 12/15/23 14 Draft PER to Town and 0 days Mon Mon 12/18

MDE 12/18/23 12/18/23

15 Review Draft PER 8 wks Mon 12/18/23Fri 2/9/24 16 Incorporate Comments 2 wks Mon 2/12/24Fri 2/23/24 17 Finalize PER 2 wks Mon 2/26/24Fri 3/8/24 18 Develop Design Proposal4 wks Mon 12/18/23Fri 1/12/24 19 Town Reviews Design 2 wks Mon 1/15/24Fri 1/26/24 Proposal 20 ENR Upgrade Design 390 days Mon 1/29/24Fri 7/25/25 21 Project Set Up 2 wks Mon 1/29/24Fri 2/9/24 22 Design Kick Off w Town 0 days Mon 2/12/24Mon 2/12/24 2/12

23 30% Design 8 wks Mon 2/12/24Fri 4/5/24 24 30% Design Internal QA 2 wks Mon 4/8/24 Fri 4/19/24 25 30% Design to Town 0 days Mon 4/22/24Mon 4/22/24 4/22 26 Town Reviews 30% Design2 wks Mon 4/22/24Fri 5/3/24 27 30% Design Comment 0 days Mon 5/6/24 Mon 5/6/24 5/6 Review Meeting 28 60% Design 10 wks Mon 5/6/24 Fri 7/12/24 29 60% Design Internal QA 2 wks Mon 7/15/24Fri 7/26/24 30 60% Design to Town 0 days Mon 7/29/24Mon 7/29/24 7/29

31 Town Reviews 60% Design2 wks Mon 7/29/24Fri 8/9/24 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 8.1: Project PImagpele 1mentation Schedule

ID Task Name Duration Start Finish 2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 32 60% Design Comment 0 days Mon 8/12/24Mon 8/12/24 8/12 Review Meeting 33 Pre-Final Design 10 wks Mon 8/12/24Fri 10/18/24 34 Pre-Final Design Internal2 wks Mon Fri 11/1/24

QA 10/21/24

35 Pre-Final Design to Town0 days Mon 11/4/24Mon 11/4/24 11/4 36 Town Reviews Pre-Final 2 wks Mon 11/4/24Fri 11/15/24 Design 37 Pre-Final Design 0 days Mon Mon 11/18 Comment Review 11/18/24 11/18/24 38 Design Review Meeting 2 wks Mon Fri 11/29/24 with MDE 11/18/24 39 MDE Review 8 wks Mon 12/2/24Fri 1/24/25 40 Permitting 12 wks Mon 1/27/25Fri 4/18/25 41 Develop Bid Ready 4 wks Mon 4/21/25Fri 5/16/25

Documents 42 Bid Ready Doc Internal QA2 wks Mon 5/19/25Fri 5/30/25 43 Bid Ready Docs to Town 0 days Mon 6/2/25 Mon 6/2/25 6/2 44 Town Finalizes Funding 8 wks Mon 6/2/25 Fri 7/25/25 45 ENR Upgrade and 130 days Mon Fri 1/23/26 Expansion Bidding 7/28/25 46 Town Prepares for 4 wks Mon 7/28/25Fri 8/22/25 Advertisement 47 Advertise 12 wks Mon 8/25/25Fri 11/14/25 48 Open Bids 0 days Mon 11/17/25Mon 11/17/25 11/17

49 Bid Review 2 wks Mon 11/17/25Fri 11/28/25 50 Bid Recommendation to 0 days Mon 12/1/25Mon 12/1/25 12/1

MDE

51 MDE Bid Review 4 wks Mon 12/1/25Fri 12/26/25 52 Construction NTP 4 wks Mon 12/29/25Fri 1/23/26 53 ENR Upgrade and Exp 910 days Mon Mon Construction 1/26/26 7/23/29 54 Issue PO's 2 wks Mon 1/26/26Fri 2/6/26 55 Shop Drawing 16 wks Mon 2/9/26 Fri 5/29/26 Submittals and Review 56 Major Equipment Delivery36 wks Mon 6/1/26 Fri 2/5/27 57 Mobilize Site 0 days Mon 2/8/27 Mon 2/8/27 2/8 58 Construction 104 wks Mon 2/8/27 Fri 2/2/29

59 Substantial Completion 0 days Mon 2/5/29 Mon 2/5/29 2/5 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 8.1: Project PImagpele 2mentation Schedule

ID Task Name Duration Start Finish 2023 2024 2025 2026 2027 2028 2029 2030 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 60 Operations Process 2 wks Mon 2/5/29 Fri 2/16/29 Training 61 Commissioning and 12 wks Mon 2/19/29Fri 5/11/29 Start Up 62 Process Testing 4 wks Mon 5/14/29Fri 6/8/29 63 Develop Punchlist 2 wks Mon 6/11/29Fri 6/22/29 64 Project Closeout 4 wks Mon 6/25/29Fri 7/20/29

65 Final Completion 0 days Mon 7/23/29Mon 7/23/29 7/23 Task Project Summary Manual Task Start-only Deadline Project: Centreville WWTP ENR Split Inactive Task Duration-only Finish-only Progress Date: Mon 12/4/23 Milestone Inactive Milestone Manual Summary Rollup External Tasks Manual Progress Summary Inactive Summary Manual Summary External Milestone Figure 8.1: Project PImagpele 3mentation Schedule

Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD 9 Project Asset Management 9.1 Inventory of Critical Assets After the implementation of the Centreville WWTP ENR Upgrade and Expansion project the following will be the Town’s Critical Assets at the WWTP:

1. Incoming Power Distribution

2. Back Up Power Generator

3. Aeration Blowers - Existing

4. Aeration Blowers – New

5. Administration/Lab Building

6. Disinfection (Filter and Blower) Building

7. Control Building

8. Influent Screening Facility

a. Mechanically Cleaned Screens b. Washer/Compactor c. Concrete Channels

9. Process Tanks

a. Flow EQ Tanks b. Aerobic Digesters c. Diffusers

10. MBR Trains

a. Mixers b. Diffusers c. Internal Recycle Pumps

11. Ultraviolet Light Disinfection

12. Effluent Pump Station

13. Dewatering Facility

a. Dewatering Press b. Polymer Storage and Dosing c. Sludge Conveyor

14. Covered Cake Storage Area

9.2 Condition of Critical Assets All critical assets will be new with the exception of the following:

A. Incoming Power Distribution B. Aeration Blowers – Existing C. Administration/Lab Building D. Disinfection (Filter and Blower) Building E. Process Tanks F. Effluent Pump Station The condition of the critical assets is described below:

A. Incoming power distribution The incoming power distribution includes the utility owned transformer and cables to the overhead power system. The incoming switchboard owned by the Town is in in good condition with many years of remaining expected life.

Page 95 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD B. Aeration Blowers – Existing The three existing aeration blowers are 20 years old and are operating as designed and are in good condition. The blowers have many years of remaining expected life.

The existing aeration blowers will be used for processes that are ancillary to the treatment process, specifically to provide aeration of the two influent flow equalization tanks and the two aerated digesters.

The blowers will have a standby unit.

C. Administration/Lab Building The Administration/Lab Building will be refurbished with the project and will have many years of remaining expected life.

D. Disinfection (Filter and Blower) Building The Disinfection (Filter and Blower) Building is in good condition with many years of remaining expected life.

E. Process Tanks The concrete process tanks are in good condition with more than 30 years of remaining expected life. The mechanical equipment will be replaced with the project. Handrails, lighting, and other appurtenances will be refurbished or replaced during the upgrade.

9.3 Critical Asset Maintenance and Replacement Plan With the installation of the majority of the equipment and tanks being newly installed with the upgrade and expansion project, there is the typically a cut to maintenance budgets. In conjunction with the lower maintenance budget, the Town must institute a replacement fund which is funded annually with the monies the Town would have spent maintaining 20+ year old equipment. Therefore, with funding similar to current, the Town will be

prepared for the eventual replacement of equipment as needed with the saved funds.

9.4 Critical Asset Energy and Water Efficiency Plan There are two parts of critical asset energy and water efficiency: operational efficiency and future upgrades.

Operational efficiency refers to how the treatment process is actually operated compared with the optimal theoretical energy and water efficiency. For example, aeration is the single largest cost for the activated sludge treatment process and automating the speed of the blowers to provide just enough air to meet the process requirements, will save considerable energy compared to manually operating the blowers.

The ENR upgrade will include simple and proven process instrumentation and automation to assist the operations to operate the treatment process with operational efficiency. Examples include in tank continuous read dissolved oxygen and ammonia instruments to monitor the treatment process and adjust aeration needs automatically using Ammonia Based Aeration Control (ABAC). Chemical dosing will also have flow pacing implemented to

automatically adjust the phosphorus precipitant to adjust dosing based on continuous flow measurement inputs.

The methanol dosing will be controlled based on nitrate readings entering and leaving the second anoxic zones.

Water efficiency will be primarily through the replacement of potable water use with non-potable water everywhere practical.

Page 96 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD Future upgrades consider the improvements in energy efficiency over time. For example, at some point in the future, it is likely the ultraviolet (UV) light disinfection system installed with the ENR upgrade and expansion which is highly efficient by today’s standards, will be eclipsed by future technologies of UV disinfection, or another

completely different technology. The Town’s DPW needs to keep up to date with the latest equipment available by attending wastewater conferences, or by bringing a consulting engineer into an on call contract. The on call engineer can be tasked with reviewing the energy efficiency of the treatment processes and make recommendations for improvements.

Page 97 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

Appendix A

Cost Estimate Line Items Page 98 Centreville ENR Upgrade and 1 MGD Expansion 10-May-24 Town of Centreville Preliminary Construction Cost Estimate Alt 1 - 4 SBR Alt 2 - Act Sludge Alt 3 - MBR Alternative 3 Facilities Existing Tank Modifications $ 214,000 $ 643,000 $ 6 43,000 Clarifier Tanks, Equipment and RAS PS $ - $ 4 ,749,000 $ - Denitrification Filter Tanks, Equip and Controls $ 3 ,112,000 $ 3 ,112,000 $ -

Misc Process Piping and Equipment $ 157,000 $ 235,000 $ 7 84,000 Additional SBR Tanks, Equip, and Controls $ 3 ,564,000 $ - $ - Activated Sludge Equipment $ - $ 1 ,012,000 $ - MBR Process Equipment and Controls $ - $ - $ 5,789,000 Post EQ Tank and Equipment $ 78,000 $ - $ - Aerobic Digester Tank and Equipment $ 1 ,427,000 $ 78,000 $ 7 8,000 Ultraviolet Disinfection System $ 642,000 $ 642,000 $ 6 42,000

Pre-Flow EQ Tank, Aerated, w Pumping $ 2 ,054,000 $ 2 ,019,000 $ 2,019,000 Alternative Subtotal Cost $ 11,248,000 $ 12,490,000 $ 9,955,000 Base Facilities Interior Demolition (Lab, Control, and Filter and Blower Buildings) $ 95,000 $ 95,000 $ 9 5,000 Influent Screening Expansion $ 825,000 $ 825,000 $ 8 25,000 Methanol Facility $ 618,000 $ 618,000 $ 6 18,000 Non-Potable Water System $ 54,000 $ 54,000 $ 5 4,000

Dewatering Facility $ 2 ,413,000 $ 2 ,413,000 $ 2,413,000 Covered Cake Storage $ 835,000 $ 835,000 $ 8 35,000 Lab Building Refurb $ 139,000 $ 139,000 $ 1 39,000 Control Building Refurb $ 130,000 $ 130,000 $ 1 30,000 Filter & Blower Building Refurb $ 348,000 $ 348,000 $ 3 48,000 Base Subtotal Cost $ 5,457,000 $ 5,457,000 $ 5,457,000 Alternative Plus Base - Subtotal Construction Cost $ 16,705,000 $ 17,947,000 $ 15,412,000

Electrical $ 2 ,517,000 $ 2 ,722,000 $ 4,169,000 Site Civil, inc Yard Piping and Demo (15%) $ 2 ,505,750 $ 2 ,692,050 $ 2,311,800 Site SCADA (5%) $ 835,250 $ 897,350 $ 7 70,600 Subtotal $ 22,563,000 $ 24,258,400 $ 22,663,400 Contingency (30%) $ 6 ,769,000 $ 7 ,278,000 $ 6,799,000 WWTP ENR Total Const Cost (December 2023 Dollars) $ 29,332,000 $ 31,536,400 $ 29,462,400 Escalated to December 2026 (4%/year) $ 32,994,000 $ 35,474,000 $ 33,141,000

$ 3 ,662,000 $ 3 ,937,600 $ 3,678,600

MARK-UP SUMMARY

PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

MATERIAL LABOR EQUIPMENT

MARKUP DESCRIPTION

MARKUP % MARKUP % MARKUP %

SUBCONTRACTOR MARKUPS

Factors from Means Location Factor Tables CityCentreville and City Cost Index Tables to account for Material100.00% LOCATION FACTORS market conditions at project location Labor100.00% 0.00% 0.00% 0.00% Equipment100.00% This factor adjusts for project specific elements including: restriction on work hours, security

WORK RESTRICTION FACTOR/PHASING 0.00%

requirements, limited site access, phasing, etc.

Sales tax may be added to materials costs, equipment costs, and sub-contractor work. State =

SALES TAX ON MATERIAL & EQUIPMENT 6.00% 6.00%

MD

LABOR BURDEN 29.17%

Workers Comp. Insurance State specific; Means 2022 9.00% Fixed Overhead Federal and State Unemployment, FICA, Risk Insurance & Liability; Means 2015 18.50% Home office overhead for Installing Contractor. This markup is typically in the range of 8 - 12%

INSTALLING CONTRACTOR OVERHEAD 10.00% 10.00% 10.00%

Profit for Installing Contractor. This markup is typically in the range of 8 - 12%

INSTALLING CONTRACTOR PROFIT 10.00% 10.00% 10.00%

TOTAL MARKUP - SUBCONTRACTOR 1.283 1.563 1.283

PRIME CONTRACTOR MARKUPS

Job office overhead costs including quality control, temporary facilities, project security, clean-up, GENERAL REQUIREMENTS & CQC etc. Line items (Div 01) or percentage can be used. Typically 5% - 15% of project cost, including 5.00% 5.00% 5.00% 3% CQC.

Home office overhead for Prime contractor. This markup is typically in the range of 5 - 10%. For

PRIME OVERHEAD 8.25% 8.25% 8.25%

small projects self-performed by the Prime, this could be 0%.

Profit for Prime Contractor. This markup is typically in the range of 5 - 10%. For small projects self-

PRIME PROFIT 6.00% 6.00% 6.00%

performed by the Prime, this could be 0%.

The bond is used to pay for completion of construction if the contractor fails to do so. Typically

BOND 1.50% 1.50% 1.50%

ranges from 0.5% - 2%, depending on Contractor's past performance.

Cost growth (escalation) from the date of the estimate to the estimated mid-point of construction.

ESCALATION Source of escalation index = (Means, ENR, NAVFAC, etc.) 0.00% 0.00% 0.00% *Note: Escalation is calculated in summary spreadsheet Required to account for cost of unknowns based on level of design development.

DESIGN CONTINGENCY 0.00% 0.00% 0.00%

MISC. PROJECT-SPECIFIC MARKUP (Enter description here. This will not be used for most projects.)

TOTAL MARKUP - PRIME CONTRACTOR 1.223 1.223 1.223

TOTAL MARKUP - COMBINED 1.568 1.911 1.568

Mark-up Summary 2023 PER Cost Estimate - Centreville WWTP.xlsx Page 1 of 1

DETAILED COST: GENERAL REQUIREMENTS

PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

ITEM DESCRIPTION UNIT OF UNIT COSTS TOTAL COSTS

SOURCE QUANTITY TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

3 existing buildings: miscellaneous interior

1 LS $ - $ 5 0,000.00 $ - $ - $ 5 0,000 $ - $ 5 0,000

demolition of interior partitions, casework, etc.

NEW WORK

Dewatering Building 1960 Sq Ft $ 1 50.00 $ 1 50.00 $ 1 0.00 $ 2 94,000 $ 2 94,000 $ 1 9,600 $ 6 07,600 Alfa Laval Quote 2m Belt Filter Press 1 LS $ 3 85,500.00 $ 1 15,650.00 $ - $ 3 85,500 $ 1 15,650 $ - $ 5 01,150 Sludge Conveyors 1 LS $ 1 00,000.00 $ 1 00,000.00 $ - $ 1 00,000 $ 1 00,000 $ - $ 2 00,000 Polymer System 1 LS $ 1 00,000.00 $ 1 5,000.00 $ - $ 1 00,000 $ 1 5,000 $ - $ 1 15,000 Non-Potable Water System 1 LS $ 2 5,000.00 $ 7 ,500.00 $ - $ 2 5,000 $ 7 ,500 $ - $ 3 2,500

Influent Screening Concrete 100 CY $ 4 00.00 $ 4 00.00 $ - $ 4 0,000 $ 4 0,000 $ - $ 8 0,000 Huber Quote Influent Screens 2 ea $ 1 60,000.00 $ 4 8,000.00 $ - $ 3 20,000 $ 9 6,000 $ - $ 4 16,000 Methanol Facility 1 LS $ 1 50,000.00 $ 2 00,000.00 $ - $ 1 50,000 $ 2 00,000 $ - $ 3 50,000 Covered Cake Storage 3200 Sq Ft $ 7 5.00 $ 7 5.00 $ - $ 2 40,000 $ 2 40,000 $ - $ 4 80,000 Lab Building Refurbishment 800 Sq Ft $ 5 0.00 $ 5 0.00 $ - $ 4 0,000 $ 4 0,000 $ - $ 8 0,000

Control Building Refurbishment 750 Sq Ft $ 5 0.00 $ 5 0.00 $ - $ 3 7,500 $ 3 7,500 $ - $ 7 5,000 Filter & Blower Building Refurbishment 2000 Sq Ft $ 5 0.00 $ 5 0.00 $ - $ 1 00,000 $ 1 00,000 $ - $ 2 00,000

SUBTOTAL DIRECT COSTS $ 1,832,000 $ 1,335,650 $ 19,600 $ 3 ,187,250

SUBCONTRACTOR MARKUP $ 517,723 $ 751,833 $ 5,539 $ 1 ,275,095

SUBTOTAL $ 2,349,723 $ 2,087,483 $ 25,139 $ 4 ,462,345

PRIME CONTRACTOR MARKUP $ 523,741 $ 465,289 $ 5,603 $ 9 94,634

BASE BID DIVISION 1 - TOTAL COSTS $ 2,873,464 $ 2,552,772 $ 30,742 $ 5 ,456,979 00 General Requirements (2) 2023 PER Cost Estimate - Centreville WWTP.xlsx Page 1 of 1 DETAILED COST: ALTERNATIVE 1 - SBRs PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

ITEM DESCRIPTION UNIT OF UNIT COSTS TOTAL COSTS

SOURCE QUANTITY TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

$ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ -

NEW WORK

Evoqua Budget Quote Closed Vessel Low Pressure UV System 1 ls $ 3 57,448.00 $ 1 07,234.40 $ - $ 3 57,448 $ 1 07,234 $ - $ 464,682 $ - $ - $ - $ - Leopold Budget Quote Denitrification Filters Equipment 1 ls $ 1 ,500,000.00 $ 4 50,000.00 $ - $ 1 ,500,000 $ 4 50,000 $ - $ 1,950,000 Denitrifiction Concrete 300 CY $ 4 00.00 $ 4 00.00 $ - $ 1 20,000 $ 1 20,000 $ - $ 240,000 $ - $ - $ - $ - AquaSBR Budget Quote AquaSBR System 1 ls $ 8 21,640.00 $ 2 46,492.00 $ - $ 8 21,640 $ 2 46,492 $ - $ 1,068,132

2 x SBR Tank Concrete 1500 CY $ 4 00.00 $ 4 00.00 $ - $ 6 00,000 $ 6 00,000 $ - $ 1,200,000 $ - $ - $ - $ - $ - $ - $ - Existing Tank Modifications 1 LS $ 1 00,000.00 $ 3 0,000.00 $ - $ 1 00,000 $ 3 0,000 $ - $ 130,000 $ - $ - $ - $ - $ - $ - $ - Misc Process Piping 1 LS $ 1 00,000.00 $ - $ - $ 1 00,000 $ - $ - $ 100,000 $ - $ - $ - $ - $ - $ - $ - Post EQ Modifications 1 LS $ 5 0,000.00 $ - $ - $ 5 0,000 $ - $ - $ 50,000

$ - $ - $ - $ - $ - $ - $ - Pre-Eq Tank Concrete 750 CY $ 4 00.00 $ 4 00.00 $ - $ 3 00,000 $ 3 00,000 $ - $ 600,000 Pre-Eq Pumps, Blowers and Diffusers 1 LS $ 4 00,000.00 $ 2 00,000.00 $ - $ 4 00,000 $ 2 00,000 $ - $ 600,000 $ - $ - $ - $ - $ - $ - $ - Aerobic Digester Concrete 900 CY $ 4 00.00 $ 4 00.00 $ - $ 3 60,000 $ 3 60,000 $ - $ 720,000 Aerobic Digester Blowers and Equipment 1 LS $ 5 0,000.00 $ 5 0,000.00 $ - $ 5 0,000 $ 5 0,000 $ - $ 100,000

$ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ -

SUBTOTAL DIRECT COSTS $ 4,759,088 $ 2,463,726 $ - $ 7,222,814

SUBCONTRACTOR MARKUP $ 587,808 $ 1,386,823 $ - $ 1,974,631

SUBTOTAL $ 5,346,896 $ 3,850,549 $ - $ 9,197,445

PRIME CONTRACTOR MARKUP $ 1,191,796 $ 858,268 $ - $ 2,050,063

BASE BID DIVISION 1 - TOTAL COSTS $ 6,538,692 $ 4,708,817 $ - $ 11,247,508 Option 1 - 4 SBRs (2) 2023 PER Cost Estimate - Centreville WWTP.xlsx Page 1 of 1 DETAILED COST: ALTERNATIVE 1 (SBRs) - ELECTRICAL PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion CLIENT: ESTIMATED BY:

Town of Centreville WRA, DEI Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

UNIT OF UNIT COSTS TOTAL COSTS

SOURCE ITEM DESCRIPTION QUANTITY TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

Demolition 1 LS $ - $ 1 00,000.00 $ - $ - $ 1 00,000 $ - $ 1 00,000

NEW WORK

Filter Building 600A Motor Control Center (MCC-A) 1 EA $ 2 00,000.00 $ 2 0,000.00 $ - $ 2 00,000 $ 2 0,000 $ - $ 2 20,000 Branch Circuit Wiring from MCC-A 1 LS $ 1 00,000.00 $ 1 50,000.00 $ - $ 1 00,000 $ 1 50,000 $ - $ 2 50,000 New Feeder for 600 MCC-A 1 LS $ 1 5,000.00 $ 3 ,500.00 $ - $ 1 5,000 $ 3 ,500 $ - $ 1 8,500 Existing Panel DP modifications including new

1 LS $ 3 0,000.00 $ 1 5,000.00 $ - $ 3 0,000 $ 1 5,000 $ - $ 4 5,000

breakers and branch circuits Lighting and Branch Wiring 2000 SF $ 7 .00 $ 5 .00 $ - $ 1 4,000 $ 1 0,000 $ - $ 2 4,000 Lab Building 208V Panelboard 2 EA $ 1 0,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 750 SF $ 6 .00 $ 4 .00 $ - $ 4 ,500 $ 3 ,000 $ - $ 7 ,500 Receptacles including branch wiring 750 SF $ 2 .00 $ 3 .00 $ - $ 1 ,500 $ 2 ,250 $ - $ 3 ,750 Dewatering Building

480V Panelboard 1 EA $ 1 5,000.00 $ 3 ,000.00 $ - $ 1 5,000 $ 3 ,000 $ - $ 1 8,000 208V Panelboard 2 EA $ 1 0,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 1900 SF $ 7 .00 $ 5 .00 $ - $ 1 3,300 $ 9 ,500 $ - $ 2 2,800 Receptacles including branch wiring 1900 SF $ 3 .00 $ 4 .00 $ - $ 5 ,700 $ 7 ,600 $ - $ 1 3,300 Branch circuits for mechanical loads 1900 SF $ 6 .00 $ 8 .00 $ - $ 1 1,400 $ 1 5,200 $ - $ 2 6,600

Dry type transformer 45kVA 2 EA $ 2 ,500.00 $ 1 ,250.00 $ - $ 5 ,000 $ 2 ,500 $ - $ 7 ,500 Outside 600A Motor Control Center (MCC-B) including 1 EA $ 1 50,000.00 $ 4 0,000.00 $ - $ 1 50,000 $ 4 0,000 $ - $ 1 90,000 VFDs Branch Circuit Wiring from MCC-B including 1 LS $ 1 00,000.00 $ 1 25,000.00 $ - $ 1 00,000 $ 1 25,000 $ - $ 2 25,000 underground ducts Feeder for Dewatering Building 1 LS $ 1 0,000.00 $ 2 0,000.00 $ - $ 1 0,000 $ 2 0,000 $ - $ 3 0,000

Feeder for Control Building 1 LS $ 5 ,000.00 $ 8 ,000.00 $ - $ 5 ,000 $ 8 ,000 $ - $ 1 3,000 Site Lighting and Branch Wiring 1 LS $ 4 0,000.00 $ 4 0,000.00 $ - $ 4 0,000 $ 4 0,000 $ - $ 8 0,000 Testing and Commisioning 1 LS $ - $ 4 0,000.00 $ - $ - $ 4 0,000 $ - $ 4 0,000 Grounding and Bonding 1 LS $ 2 5,000.00 $ 5 0,000.00 $ - $ 2 5,000 $ 5 0,000 $ - $ 7 5,000

SUBTOTAL DIRECT COSTS $ 785,400 $ 672,550 $ - $ 1 ,457,950

SUBCONTRACTOR MARKUP $ 221,954 $ 378,617 $ - $ 600,571

SUBTOTAL $ 1,007,354 $ 1,051,167 $ - $ 2,058,521

PRIME CONTRACTOR MARKUP $ 224,534 $ 234,300 $ - $ 458,834

BASE BID DIVISION 16 - TOTAL COSTS $ 1,231,888 $ 1,285,466 $ - $ 2 ,517,354 Div 16 Cost Estimate - Alternative 1.xlsx Page 1 of 1

DETAILED COST: ALTERNATIVE 2 - CONVENTIONAL ACTIVATED SLUDGE

PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

SOURCE ITEM DESCRIPTION QUANTITY UNIT OF UNIT COSTS TOTAL COSTS TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

$ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ -

NEW WORK

Brentwood Budget Quote 60' Dia. Sludge Rapid Removal Clarifiers 2 ea $ 4 94,750.00 $ 2 47,375.00 $ - $ 9 89,500 $ 4 94,750 $ - $ 1 ,484,250 Clarifier Concrete 1300 CY $ 4 00.00 $ 4 00.00 $ - $ 5 20,000 $ 5 20,000 $ - $ 1 ,040,000 RAS Pump Station 1 LS $ 5 00,000.00 $ - $ - $ 5 00,000 $ - $ - $ 5 00,000 Evoqua Budget Quote Closed Vessel Low Pressure UV System 1 ls $ 3 57,448.00 $ 1 07,234.40 $ - $ 3 57,448 $ 1 07,234 $ - $ 4 64,682

Leopold Budget Quote Denitrification Filters 1 ls $ 1 ,500,000.00 $ 4 50,000.00 $ - $ 1 ,500,000 $ 4 50,000 $ - $ 1 ,950,000 Denitrifcation Concrete 300 CY $ 4 00.00 $ 4 00.00 $ - $ 1 20,000 $ 1 20,000 $ - $ 2 40,000 Internal Recycle Pumps 8 ea $ 2 5,000.00 $ 7 ,500.00 $ 2 00,000 $ 6 0,000 $ - $ 2 60,000 Fine Bubble Diffusers and Blowers 1 LA $ 2 50,000.00 $ 1 00,000.00 $ - $ 2 50,000 $ 1 00,000 $ - $ 3 50,000

Reactor Tank Modifications 1 LS $ 4 0,000.00 $ 1 2,000.00 $ - $ 4 0,000 $ 1 2,000 $ - $ 5 2,000 Reactor Tank Concrete 400 CY $ 4 00.00 $ 4 00.00 $ - $ 1 60,000 $ 1 60,000 $ - $ 3 20,000 Misc Process Piping and Equipment 1 LS $ 1 50,000.00 $ - $ - $ 1 50,000 $ - $ - $ 1 50,000 Aerobic Digester Tank Modifications 1 LS $ 5 0,000.00 $ - $ - $ 5 0,000 $ - $ - $ 5 0,000 Pre-Eq Pumps, Blowers and Diffusers 2 LS $ 4 00,000.00 $ 2 00,000.00 $ - $ 8 00,000 $ 4 00,000 $ - $ 1 ,200,000

SUBTOTAL DIRECT COSTS $ 5,636,948 $ 2,423,984 $ - $ 8 ,060,932

SUBCONTRACTOR MARKUP $ 788,454 $ 1,364,452 $ - $ 2,152,906

SUBTOTAL $ 6,425,402 $ 3,788,437 $ - $ 10,213,839

PRIME CONTRACTOR MARKUP $ 1,432,189 $ 844,423 $ - $ 2,276,612

BASE BID DIVISION 3 - TOTAL COSTS $ 7,857,591 $ 4,632,860 $ - $ 1 2,490,451 Option 2 - Activated Sludge (2) 2023 PER Cost Estimate - Centreville WWTP.xlsx Page 1 of 1 DETAILED COST: ALTERNATIVE 2 (CONVENTIONAL ACTIVATED SLUDGE) - ELECTRICAL PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA, DEI Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

UNIT OF UNIT COSTS TOTAL COSTS

SOURCE ITEM DESCRIPTION QUANTITY TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

Demolition 1 LS $ - $ 100,000.00 $ - $ - $ 100,000 $ - $ 1 00,000

NEW WORK

Filter Building 600A Motor Control Center (MCC-A) 1 EA $ 2 00,000.00 $ 2 0,000.00 $ - $ 2 00,000 $ 2 0,000 $ - $ 2 20,000 Branch Circuit Wiring from MCC-A 1 LS $ 1 00,000.00 $ 1 50,000.00 $ - $ 1 00,000 $ 1 50,000 $ - $ 2 50,000 New Feeder for 600 MCC-A 1 LS $ 1 5,000.00 $ 3 ,500.00 $ - $ 1 5,000 $ 3 ,500 $ - $ 1 8,500 Existing Panel DP modifications including new

1 LS $ 30,000.00 $ 15,000.00 $ - $ 30,000 $ 15,000 $ - $ 4 5,000

breakers and branch circuits Lighting and Branch Wiring 2000 SF $ 7 .00 $ 5 .00 $ - $ 1 4,000 $ 1 0,000 $ - $ 2 4,000 Lab Building 208V Panelboard 2 EA $ 1 0,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 750 SF $ 6 .00 $ 4 .00 $ - $ 4 ,500 $ 3 ,000 $ - $ 7 ,500 Receptacles including branch wiring 750 SF $ 2 .00 $ 3 .00 $ - $ 1 ,500 $ 2 ,250 $ - $ 3 ,750 Dewatering Building

480V Panelboard 1 EA $ 1 5,000.00 $ 3 ,000.00 $ - $ 1 5,000 $ 3 ,000 $ - $ 1 8,000 208V Panelboard 2 EA $ 1 0,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 1900 SF $ 7 .00 $ 5 .00 $ - $ 1 3,300 $ 9 ,500 $ - $ 2 2,800 Receptacles including branch wiring 1900 SF $ 3 .00 $ 4 .00 $ - $ 5 ,700 $ 7 ,600 $ - $ 1 3,300 Branch circuits for mechanical loads 1900 SF $ 6 .00 $ 8 .00 $ - $ 1 1,400 $ 1 5,200 $ - $ 2 6,600

Dry type transformer 45kVA 2 EA $ 2 ,500.00 $ 1 ,250.00 $ - $ 5 ,000 $ 2 ,500 $ - $ 7 ,500 Outside 600A Motor Control Center (MCC-B) including

1 EA $ 2 00,000.00 $ 40,000.00 $ - $ 200,000 $ 40,000 $ - $ 2 40,000

VFDs Branch Circuit Wiring from MCC-B including

1 LS $ 1 50,000.00 $ 150,000.00 $ - $ 150,000 $ 150,000 $ - $ 3 00,000

underground ducts Feeder for Dewatering Building 1 LS $ 1 0,000.00 $ 2 0,000.00 $ - $ 1 0,000 $ 2 0,000 $ - $ 3 0,000 Feeder for Control Building 1 LS $ 5 ,000.00 $ 8 ,000.00 $ - $ 5 ,000 $ 8 ,000 $ - $ 1 3,000 Site Lighting and Branch Wiring 1 LS $ 4 0,000.00 $ 4 0,000.00 $ - $ 4 0,000 $ 4 0,000 $ - $ 8 0,000 Testing and Commisioning 1 LS $ - $ 4 0,000.00 $ - $ - $ 4 0,000 $ - $ 4 0,000 Grounding and Bonding 1 LS $ 2 5,000.00 $ 5 0,000.00 $ - $ 2 5,000 $ 5 0,000 $ - $ 7 5,000

SUBTOTAL DIRECT COSTS $ 885,400 $ 697,550 $ - $ 1,582,950

SUBCONTRACTOR MARKUP $ 250,214 $ 392,691 $ - $ 642,905

SUBTOTAL $ 1,135,614 $ 1,090,241 $ - $ 2,225,855

PRIME CONTRACTOR MARKUP $ 253,123 $ 243,009 $ - $ 496,132

BASE BID DIVISION 16 - TOTAL COSTS $ 1,388,737 $ 1,333,250 $ - $ 2,721,986 Div 16 Cost Estimate - Alternative 2.xlsx Page 1 of 1

DETAILED COST: ALTERNATIVE 3 - MBR ACTIVATED SLUDGE

PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000

ITEM DESCRIPTION UNIT OF UNIT COSTS TOTAL COSTS

SOURCE QUANTITY TOTAL

MEASURE MATERIAL LABOR EQUIPMENT MATERIAL LABOR EQUIPMENT

DEMOLITION

$ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ -

NEW WORK

Evoqua Budget Quote Closed Vessel Low Pressure UV System (1/2 for MBR) 1 ls $ 3 57,448.00 $ 1 07,234.40 $ - $ 3 57,448 $ 1 07,234 $ - $ 4 64,682 QuoteMBR Equipment 1 ls $ 4 ,000,000.00 $ - $ - $ 3 ,000,000 $ 1 ,000,000 $ - $ 4 ,000,000 New MBR Process Building 400 SF $ 1 50.00 $ 1 50.00 $ - $ 6 0,000 $ 6 0,000 $ - $ 1 20,000 Reactor Tank Modifications 1 LS $ 4 0,000.00 $ 1 2,000.00 $ - $ 4 0,000 $ 1 2,000 $ - $ 5 2,000

Reactor Tank Concrete 400 CY $ 4 00.00 $ 4 00.00 $ - $ 1 60,000 $ 1 60,000 $ - $ 3 20,000 Misc Process Piping 1 LS $ 5 00,000.00 $ - $ - $ 5 00,000 $ - $ - $ 5 00,000 Pre-Eq Pumps, Blowers and Diffusers 2 LS $ 4 00,000.00 $ 2 00,000.00 $ - $ 8 00,000 $ 4 00,000 $ - $ 1 ,200,000 Aerobic Digester Tank Modifications 1 LS $ 5 0,000.00 $ - $ - $ 5 0,000 $ - $ - $ 5 0,000

SUBTOTAL DIRECT COSTS $ 4 ,967,448 $ 1 ,739,234 $ - $ 6 ,706,682

SUBCONTRACTOR MARKUP $ 4 54,986 $ 9 79,009 $ - $ 1,433,995

SUBTOTAL $ 5 ,422,434 $ 2 ,718,243 $ - $ 8,140,677

PRIME CONTRACTOR MARKUP $ 1 ,208,633 $ 6 05,882 $ - $ 1,814,515

BASE BID DIVISION 4 - TOTAL COSTS $ 6 ,631,067 $ 3 ,324,126 $ - $ 9 ,955,192 Option 3 - MBRs (2) 2023 PER Cost Estimate - Centreville WWTP.xlsx Page 1 of 1

DETAILED COST: ALTERNATIVE 3 (MBR ACTIVATED SLUDGE) - ELECTRICAL

PROJECT NAME: Centreville WWTP ENR Upgrade and Expansion PER CLIENT: ESTIMATED BY:

Town of Centreville WRA, DEI Centreville,

PROJECT LOCATION: DESIGN SUBMISSION: WORK ORDER NUMBER:

Maryland PER 14375-000 SOURCE ITEM DESCRIPTION QUANTITY M U E N A I S T U O R F E MATERIAL UN L IT A B C O O R STS EQUIPMENT MATERIAL TOT L A A L B C O O R STS EQUIPMENT TOTAL

DEMOLITION

Demolition 1 LS $ - $ 100,000.00 $ - $ - $ 1 00,000 $ - $ 1 00,000

NEW WORK

Filter Building 600A Motor Control Center (MCC-A) 1 EA $ 2 00,000.00 $ 20,000.00 $ - $ 2 00,000 $ 2 0,000 $ - $ 2 20,000 Branch Circuit Wiring from MCC-A 1 LS $ 1 00,000.00 $ 1 50,000.00 $ - $ 1 00,000 $ 1 50,000 $ - $ 2 50,000 New Feeder for 600 MCC-A 1 LS $ 15,000.00 $ 3 ,500.00 $ - $ 1 5,000 $ 3 ,500 $ - $ 1 8,500 Existing Panel DP modifications including new

1 LS $ 30,000.00 $ 15,000.00 $ - $ 3 0,000 $ 1 5,000 $ - $ 4 5,000

breakers and branch circuits Lighting and Branch Wiring 2000 SF $ 7 .00 $ 5 .00 $ - $ 1 4,000 $ 1 0,000 $ - $ 2 4,000 $ - Lab Building $ - 208V Panelboard 2 EA $ 10,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 750 SF $ 6 .00 $ 4 .00 $ - $ 4 ,500 $ 3 ,000 $ - $ 7 ,500 Receptacles including branch wiring 750 SF $ 2 .00 $ 3 .00 $ - $ 1 ,500 $ 2 ,250 $ - $ 3 ,750 MBR Process Building

480V Panelboard 1 EA $ 15,000.00 $ 3 ,000.00 $ - $ 1 5,000 $ 3 ,000 $ - $ 1 8,000 208V Panelboard 2 EA $ 10,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 400 SF $ 7 .00 $ 5 .00 $ - $ 2 ,800 $ 2 ,000 $ - $ 4 ,800 Receptacles including branch wiring 400 SF $ 3 .00 $ 4 .00 $ - $ 1 ,200 $ 1 ,600 $ - $ 2 ,800 Branch circuits for mechanical loads 400 SF $ 6 .00 $ 8 .00 $ - $ 2 ,400 $ 3 ,200 $ - $ 5 ,600

Dry type transformer 45kVA 2 EA $ 2 ,500.00 $ 1 ,250.00 $ - $ 5 ,000 $ 2 ,500 $ - $ 7 ,500 Dewatering Building 480V Panelboard 1 EA $ 15,000.00 $ 3 ,000.00 $ - $ 1 5,000 $ 3 ,000 $ - $ 1 8,000 208V Panelboard 2 EA $ 10,000.00 $ 2 ,000.00 $ - $ 2 0,000 $ 4 ,000 $ - $ 2 4,000 Lighting and Branch Wiring 1900 SF $ 7 .00 $ 5 .00 $ - $ 1 3,300 $ 9 ,500 $ - $ 2 2,800 Receptacles including branch wiring 1900 SF $ 3 .00 $ 4 .00 $ - $ 5 ,700 $ 7 ,600 $ - $ 1 3,300

Branch circuits for mechanical loads 1900 SF $ 6 .00 $ 8 .00 $ - $ 1 1,400 $ 1 5,200 $ - $ 2 6,600 Dry type transformer 45kVA 2 EA $ 2 ,500.00 $ 1 ,250.00 $ - $ 5 ,000 $ 2 ,500 $ - $ 7 ,500 Outside 600A Motor Control Center (MCC-B) including

1 EA $ 300,000.00 $ 40,000.00 $ - $ 3 00,000 $ 4 0,000 $ - $ 3 40,000

VFDs Branch Circuit Wiring from MCC-B including 1 LS $ 250,000.00 $ 2 00,000.00 $ - $ 2 50,000 $ 2 00,000 $ - $ 4 50,000 underground ducts Feeder for MBR Process Building 1 LS $ 10,000.00 $ 20,000.00 $ - $ 1 0,000 $ 2 0,000 $ - $ 3 0,000 Feeder for Dewatering Building 1 LS $ 10,000.00 $ 20,000.00 $ - $ 1 0,000 $ 2 0,000 $ - $ 3 0,000 Feeder for Control Building 1 LS $ 5 ,000.00 $ 8 ,000.00 $ - $ 5 ,000 $ 8 ,000 $ - $ 1 3,000

Site Lighting and Branch Wiring 1 LS $ 40,000.00 $ 40,000.00 $ - $ 4 0,000 $ 4 0,000 $ - $ 8 0,000 Diesel Generator 750kW including ATS 1 EA $ 5 00,000.00 $ 50,000.00 $ - $ 5 00,000 $ 5 0,000 $ - $ 5 50,000 Testing and Commisioning 1 LS $ - $ 40,000.00 $ - $ - $ 4 0,000 $ - $ 4 0,000 Grounding and Bonding 1 LS $ 25,000.00 $ 50,000.00 $ - $ 2 5,000 $ 5 0,000 $ - $ 7 5,000

SUBTOTAL DIRECT COSTS $ 1,641,800 $ 8 33,850 $ - $ 2 ,475,650

SUBCONTRACTOR MARKUP $ 4 63,973 $ 4 69,422 $ - $ 933,394

SUBTOTAL $ 2,105,773 $ 1,303,272 $ - $ 3,409,044

PRIME CONTRACTOR MARKUP $ 4 69,366 $ 2 90,493 $ - $ 759,858

BASE BID DIVISION 16 - TOTAL COSTS $ 2,575,139 $ 1,593,764 $ - $ 4 ,168,903 Div 16 Cost Estimate - Alternative 3.xlsx Page 1 of 1 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

Appendix B

Existing NPDES Stream and Spray Discharge Permits Page 99 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

Appendix C

Influent Sampling Data and 9-Year Effluent Operating Data Page 100 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report Centreville, MD Data 1: Operating Effluent Weekly Spreadsheets Stream Effluent Spray Effluent Flow BOD TSS TKN Ammonia NO2 + NO3 Total Nitrogen-N TP Ge E o . m Co e l a i n Flow BOD TSS TKN NO2 + NO3 Ammonia TP E. Coli Year Month Week MGD mg/L lbs/day mg/L lbs/day mg/L mg/L mg/L lbs/day mg/L lbs/day mg/L lbs/day MPN/100 ml MGD mg/L mg/L mg/L mg/L mg/L mg/L MPN/100 ml

1 0.320 5.50 16.15 4.50 13.43 0.79 0.27 0.90 2.73 1.69 5.07 0.09 0.26 1.00 1-Jan 2 3 0 0 . . 3 3 5 1 1 2 2 2 . . 5 0 0 0 6 5 . . 7 3 5 0 4 4 . . 5 0 0 0 1 1 2 0 . . 1 5 2 9 0 1 . . 7 2 8 1 0 0 . . 3 5 2 4 1 1 . . 7 4 4 5 4 3 . . 6 8 4 8 2 2 . . 5 6 2 5 6 6 . . 7 9 6 9 0 0 . . 0 0 7 8 0 0 . . 2 2 0 0 1 1 . . 0 0 0 0 4 0.324 1.55 4.47 2.25 5.83 1.53 0.27 1.82 5.46 3.36 10.47 0.09 0.30 1.00 0.322 2.31 4.05 0.93 2.24 0.23 0.344 7.4

1 0.355 6.00 21.97 4.00 14.65 1.04 0.33 2.57 9.38 3.61 13.20 0.07 0.25 1.00 0.368 3.88 4.50 1.09 1.99 0.25 0.473 1.8 1-Feb 2 3 0 0 . . 3 3 5 7 8 4 4 2 . . 5 6 0 9 1 7 1 . . 7 6 3 8 4 4 . . 0 7 0 5 1 1 0 3 . . 3 9 9 2 1 0 . . 5 9 6 8 0 0 . . 4 2 2 2 2 2 . . 5 6 2 8 6 7 . . 5 7 3 9 4 3 . . 0 6 7 5 1 1 0 0 . . 5 6 7 3 0 0 . . 1 0 0 9 0 0 . . 2 2 7 7 1 1 . . 0 7 0 6 0 0 . . 5 5 2 7 2 0 3 2 . . 7 4 5 0 4 4 . . 3 3 8 0 0 0 . . 9 6 0 2 2 2 . . 2 1 3 8 0 0 . . 2 2 3 0 1 1 . . 1 0 4 4 3 9 1 6 1 . . 0 5

4 0.360 6.00 17.01 4.00 11.64 0.54 1.10 2.66 7.86 3.19 9.43 0.09 0.25 3.26 0.568 2.42 4.25 0.68 2.19 0.27 0.905 5.9 1 0.367 8.50 25.67 4.00 11.76 4.79 3.51 1.91 5.52 6.69 20.23 2.33 7.25 1.00 0.238 2.44 4.33 0.80 2.48 0.20 1.180 1.8 1-Mar 2 3 0 0 . . 3 3 3 4 6 4 5 4 . . 5 5 0 0 1 1 5 3 . . 7 1 4 9 5 4 . . 0 0 0 0 1 1 4 2 . . 2 1 2 1 1 0 . . 1 8 7 0 0 0 . . 3 2 7 0 2 2 . . 1 3 4 2 6 7 . . 1 0 0 8 3 3 . . 3 1 1 2 9 9 . . 4 5 2 2 0 0 . . 1 1 7 9 0 0 . . 4 5 9 8 3 2 . . 2 0 6 0 0 0 . . 2 0 6 7 7 2 2 . . 6 1 7 5 4 4 . . 0 0 0 0 0 0 . . 8 7 0 8 2 2 . . 6 2 6 1 0 0 . . 2 2 1 0 0 0 . . 7 5 3 2 6 6 1 1 . . 9 8

4 0.336 4.50 12.03 4.50 12.03 0.95 0.20 2.74 7.41 3.69 9.97 0.31 0.83 2.05 1 1-Apr 2 3 4 0.378 4.48 5.40 1.20 1.48 0.27 0.342 1.8 1 0.472 4.13 6.08 1.08 1.40 0.24 0.763 5.0 1-May 2 3 0 0 . . 2 6 8 1 9 9 4 4 . . 5 3 1 7 3 0 . . 7 9 4 4 1 0 . . 0 4 2 2 1 1 . . 1 6 4 0 0 0 . . 2 1 6 2 1 1 . . 8 5 6 7 1 2 6 1 . . 7 8 4 0.481 3.27 2.56 0.73 1.66 0.13 1.328 1.9 1 0.245 6.26 1.30 1.04 1.61 0.14 1.689 4.3

1-Jun 2 3 0 0 . . 2 1 9 7 8 3 1 1 . . 4 8 7 9 2 1 . . 7 4 5 4 0 0 . . 5 7 0 0 2 2 . . 0 0 8 0 0 0 . . 1 1 3 2 0 0 . . 9 5 7 3 3 1 1 1 . . 8 8 2014 4 1 1-Jul 2 3 4 0.0717 3.46 3.22 0.39 1.67 0.16 0.596 3.6 1 0.306 3.36 1.44 0.37 1.64 0.16 1.582 1.8 1-Aug 2 3 0 0 . . 3 3 9 8 5 2 3 3 . . 8 0 3 4 1 0 . . 2 5 2 6 0 1 . . 3 3 4 6 1 1 . . 2 5 6 2 0 0 . . 3 6 2 4 2 3 . . 2 1 4 4 4 3 2 4 . . 0 5 4 0.597 3.97 1.10 0.97 1.56 0.15 3.151 6.4

1 0.506 5.22 1.88 0.86 1.67 0.18 2.574 1.9 1-Sep 2 3 0 0 . . 3 2 2 7 3 4 4 1 . . 2 7 3 1 2 1 . . 5 3 6 0 1 1 . . 0 0 3 5 1 1 . . 7 5 0 9 0 0 . . 1 1 5 5 1 1 . . 8 6 1 8 5 4 1 1 . . 8 8 4 0.170 2.41 0.88 0.98 1.64 0.18 1.408 1.8 1 1-Oct 2 3 4 0.060 2.59 1.81 1.01 1.32 0.29 0.899 1.8 1 0.201 3.23 0.75 0.59 1.07 0.11 1.348 4.5 1-Nov 2 3 0 0 . . 5 2 6 4 4 5 4 3 . . 0 3 8 4 3 1 . . 0 1 0 9 0 0 . . 6 5 8 3 1 1 . . 7 1 0 7 0 0 . . 1 1 1 2 2 2 . . 0 5 5 3 6 8 1 1 1 4 . . 0 6

4 1 0.315 1.28 3.46 0.50 1.35 1.00 0.10 2.05 5.54 3.05 8.24 0.18 0.50 1.00 1-Dec 2 3 0 0 . . 3 3 0 0 6 3 4 2 . . 1 3 9 1 1 5 0 . . 6 9 9 4 2 1 . . 5 0 0 0 6 2 . . 5 4 3 8 0 0 . . 8 9 8 0 0 0 . . 1 1 5 3 1 1 . . 9 8 9 9 5 4 . . 2 6 4 4 2 2 . . 8 7 7 9 7 6 . . 5 8 6 6 0 0 . . 1 1 4 3 0 0 . . 3 3 7 1 1 1 . . 0 0 0 0 4 0.319 9.00 32.58 4.00 14.48 0.75 0.20 2.43 8.80 3.18 11.52 0.10 0.36 1.00 1 0.315 2.06 5.09 0.50 1.23 1.00 0.12 1.90 4.65 2.90 7.10 0.11 0.27 1.80

1-Jan 2 3 0 0 . . 3 3 3 7 2 3 2 6 . . 8 3 6 2 1 9 6 . . 0 7 9 2 0 2 . . 5 2 0 5 1 5 . . 5 9 9 3 1 0 . . 7 8 4 0 0 0 . . 1 1 0 5 1 1 . . 8 9 7 5 5 5 . . 9 2 5 1 3 2 . . 6 7 1 5 1 7 1 .3 .4 6 6 0 0 . . 1 0 0 9 0 0 . . 3 2 2 5 1 1 . . 0 4 0 1 4 0.376 2.22 6.58 2.25 6.75 0.94 0.16 1.49 4.38 2.43 7.14 0.15 0.43 1.41 1 0.344 3.08 9.30 0.50 1.52 0.72 0.11 1.58 4.82 2.29 7.03 0.23 0.71 1.00 1-Feb 2 3 0 0 . . 3 3 2 2 1 0 3 2 . . 2 2 0 0 8 5 . . 7 5 2 6 1 0 . . 2 5 5 0 3 1 . . 4 2 9 7 0 0 . . 6 4 3 5 0 0 . . 1 1 2 0 1 1 . . 1 9 9 0 3 4 . . 2 8 6 3 1 2 . . 8 3 2 5 4 5 . . 9 9 9 6 0 0 . . 1 1 4 6 0 0 . . 3 4 9 1 1 7 . . 7 1 6 0

4 0.322 2.10 5.74 6.50 17.72 0.60 0.14 1.24 3.38 1.84 5.00 0.20 0.54 1.00 1 0.412 3.67 12.00 0.75 2.50 0.60 0.16 1.84 6.04 2.44 8.02 0.15 0.49 8.92 1-Mar 2 3 0 0 . . 4 4 1 1 5 1 5 3 . . 8 0 1 8 1 1 9 1 . . 6 3 1 7 0 1 . . 7 0 5 0 2 3 . . 5 7 4 7 0 1 . . 7 1 9 7 0 0 . . 2 1 1 0 2 1 . . 0 9 6 2 6 7 . . 9 2 5 3 2 3 . . 8 0 5 8 1 9 1 .6 .4 0 0 0 0 . . 3 3 1 1 1 1 . . 0 1 4 9 3 6 8 . . 8 7 2 8 4 0.366 4.64 14.22 1.00 3.10 0.67 0.22 2.08 6.50 2.75 8.59 0.26 0.81 7.96

1 1-Apr 2 3 4 1 1-May 2 3 4 1 1-Jun 2 3 2015 4 1 1-Jul 2 3 4 1 1-Aug 2 3 4 1 1-Sep 2 3 4 1 1-Oct 2 3 4 1 1-Nov 2 3 4 1 0.431 1.59 5.62 0.50 1.82 0.40 0.12 2.30 8.36 2.69 9.80 0.14 0.49 4.02 1-Dec 2 3 0 0 . . 3 4 9 1 7 3 3 2 . . 2 3 0 5 1 8 0 . . 5 4 8 9 0 0 . . 7 5 5 0 2 1 . . 4 7 4 4 0 0 . . 4 4 0 0 0 0 . . 1 1 0 0 1 2 . . 9 6 7 0 6 9 . . 6 0 7 3 2 2 . . 3 9 7 9 1 8 0 .0 .4 1 1 0 0 . . 1 1 5 9 0 0 . . 4 6 9 6 3 1 2 3 . . 2 1 3 0

4 0.478 2.22 10.18 0.50 2.13 0.45 0.11 2.31 9.85 2.76 11.81 0.16 0.71 12.46 1 0.406 2.24 7.77 1.75 6.11 0.44 0.10 2.88 10.01 3.31 11.53 0.14 0.49 11.65 1-Jan 2 3 0 0 . . 4 4 0 3 1 9 3 2 . . 4 0 2 0 8 6 . . 2 6 8 0 2 0 . . 2 5 5 0 7 1 . . 5 6 2 2 0 0 . . 4 4 0 8 0 0 . . 2 1 3 7 3 2 . . 6 5 1 6 9 8 . . 0 1 7 2 4 3 . . 0 0 0 5 1 9 0 .6 .1 6 7 0 0 . . 4 2 7 2 1 0 . . 1 7 7 0 1 5 4 8 4 . . 3 5 0 0 4 0.424 2.81 8.83 1.00 3.31 0.36 0.10 2.85 9.44 3.21 10.61 0.17 0.57 50.02

1 0.481 4.29 16.80 0.75 2.94 0.35 0.31 1.68 6.59 2.03 7.95 0.26 1.00 8.12 1-Feb 2 3 0 0 . . 4 4 6 7 9 3 1 1 . . 3 7 1 4 5 7 . . 2 3 6 0 0 2 . . 5 5 0 0 1 2 0 . . 0 3 1 5 0 0 . . 8 3 5 3 0 0 . . 1 2 6 4 1 2 . . 9 4 9 6 1 8 0 .0 .1 0 8 2 2 . . 8 7 4 9 1 1 1 1 . . 4 5 0 8 0 0 . . 1 1 3 3 0 0 . . 5 5 2 4 1 1 . . 0 0 0 0 4 0.470 1.33 5.49 0.75 3.05 0.72 0.12 1.73 7.44 2.45 10.64 0.13 0.57 1.00 1 0.457 1.00 3.77 2.00 7.54 0.38 0.23 1.97 7.43 2.35 8.85 0.13 0.49 4.88

1-Mar 2 3 0 0 . . 4 4 6 4 1 9 1 1 . . 8 1 7 0 8 4 . . 1 0 0 6 1 0 . . 5 5 0 0 6 1 . . 1 8 6 6 0 0 . . 3 3 7 7 0 0 . . 1 1 9 3 2 2 . . 0 2 4 6 8 8 . . 6 3 0 0 2 2 . . 4 6 1 3 1 9 0 .7 .1 1 5 0 0 . . 1 1 3 9 0 0 . . 5 7 2 0 1 4 . . 4 3 1 8 4 0.414 2.79 10.44 1.25 4.82 0.39 0.11 2.23 8.40 2.61 9.85 0.33 1.21 1.00 1 1-Apr 2 3 4 1 1-May 2 3 4 1 1-Jun 2 3 2016 4 1 1-Jul 2 3 Stream Effluent Spray Effluent

Flow BOD TSS TKN Ammonia NO2 + NO3 Total Nitrogen-N TP Ge E o . m Co e l a i n Flow BOD TSS TKN NO2 + NO3 Ammonia TP E. Coli Year Month Week MGD mg/L lbs/day mg/L lbs/day mg/L mg/L mg/L lbs/day mg/L lbs/day mg/L lbs/day MPN/100 ml MGD mg/L mg/L mg/L mg/L mg/L mg/L MPN/100 ml 4 1 1-Aug 2 3 4 1 1-Sep 2 3 4 1 1-Oct 2 3 4 1 1-Nov 2 3 4 1 1-Dec 2 3 4 1 0.419 2.37 9.01 0.50 1.86 0.68 0.11 1.01 3.71 1.69 6.17 0.18 0.64 1.00

1-Jan 2 3 0 0 . . 3 3 8 7 5 2 4 3 . . 6 7 4 6 1 1 4 2 . . 3 0 3 6 4 0 . . 5 5 0 0 1 1 3 . . 5 8 7 8 1 1 . . 2 5 3 9 0 0 . . 1 4 8 3 1 1 . . 5 1 3 3 5 3 . . 0 6 6 2 2 2 . . 7 7 5 2 8 8 . . 9 6 7 3 0 0 . . 2 3 5 8 0 1 . . 8 2 2 0 1 1 . . 0 0 0 0 4 0.405 1.73 6.07 0.50 1.75 0.59 0.13 1.33 4.64 1.92 6.71 0.19 0.65 1.00 1 0.364 3.15 9.18 1.00 2.92 1.05 0.13 1.63 4.78 2.68 7.90 0.43 1.25 1.00 1-Feb 2 3 0 0 . . 3 3 7 4 0 9 2 1 . . 8 5 5 6 8 4 . . 9 7 1 2 1 0 . . 7 7 5 5 5 2 . . 6 2 5 7 0 0 . . 4 4 8 9 0 0 . . 1 1 2 1 1 1 . . 8 8 1 6 5 5 . . 6 6 3 5 2 2 . . 2 3 9 5 7 7 . . 1 1 1 7 0 0 . . 3 4 9 9 1 1 . . 2 4 0 8 1 1 . . 0 0 0 0

4 0.376 2.34 7.29 0.75 2.34 0.69 0.10 1.32 4.10 2.01 6.25 0.67 2.09 1.00 1 0.357 1.04 3.02 1.25 3.64 0.56 0.16 1.42 4.13 1.98 5.74 0.86 2.48 1.00 1-Mar 2 3 0 0 . . 4 3 0 9 4 2 2 2 . . 0 7 5 1 5 8 . . 4 8 6 3 1 2 . . 7 5 5 0 4 8 . . 5 5 7 2 0 0 . . 9 7 6 8 0 0 . . 1 1 6 9 1 1 . . 4 3 6 0 4 4 . . 1 2 9 9 2 2 . . 4 0 2 8 6 6 . . 9 8 0 9 0 0 . . 8 4 5 4 2 1 . . 4 4 7 4 1 1 . . 0 0 0 0 4 0.382 3.27 11.12 1.25 4.06 0.99 0.21 1.15 3.92 2.14 7.28 0.38 1.26 1.00

1 1-Apr 2 3 4 1 1-May 2 3 4 1 1-Jun 2 3 2017 4 1 1-Jul 2 3 4 1 1-Aug 2 3 4 1 1-Sep 2 3 4 1 1-Oct 2 3 4 1 1-Nov 2 3 4 1 0.375 1.77 5.04 2.50 7.16 0.78 0.14 1.83 5.31 2.61 7.59 0.60 1.72 1.00 1-Dec 2 3 0 0 . . 3 3 7 6 1 5 1 3 . . 8 7 0 0 1 5 0 . . 9 8 5 3 3 2 . . 0 0 0 0 9 5 . . 5 8 9 5 0 1 . . 9 4 3 3 0 0 . . 5 2 5 1 1 1 . . 8 2 0 7 5 3 . . 8 7 6 1 2 2 . . 7 7 2 0 8 7 . . 8 9 8 0 0 0 . . 5 2 2 9 1 0 . . 6 8 7 5 2 4 7 . . 4 1 5 0

4 0.371 1 0.362 5.66 16.510 2.50 7.385 0.86 0.205 1.61 4.804 2.47 7.370 0.64 1.977 44.75 1-Jan 2 3 0 0 . . 4 3 2 6 7 6 6 1 . . 1 8 9 2 0 0 2 5 1 .5 .2 3 4 6 9 2 2 . . 2 5 5 0 0 0 8 7 . . 1 6 3 3 4 1 1 1 . . 5 4 5 1 5 0 0 0 . . 6 4 1 9 2 6 0 0 . . 9 7 3 4 6 7 3 2 . . 1 2 5 9 5 9 2 2 . . 4 1 9 5 1 7 8 6 . . 5 6 0 1 6 5 0 0 . . 1 2 8 2 0 0 0 0 . . 6 6 1 7 4 1 5 2 5 8 . . 0 4 5 0 0 0 4 0.377 3.513 10.579 6.667 20.477 1.373 0.235 1.861 5.739 3.234 9.928 0.170 0.517 10.767

1 0.404 4.305 13.586 3.000 9.533 1.455 0.295 2.119 6.790 3.574 11.446 0.165 0.527 1.000 1-Feb 2 3 0 0 . . 5 4 4 7 5 4 3 3 . . 9 0 1 8 5 0 1 1 5 2 . . 7 6 8 5 3 6 5 4 . . 0 0 0 0 0 0 1 1 9 6 . . 1 4 2 3 4 4 2 1 . . 6 1 1 1 0 0 1 0 . . 4 3 7 8 7 9 1 0 . . 9 8 2 4 7 1 7 3 . . 2 4 2 5 1 5 4 3 . . 5 0 3 7 7 0 1 1 7 2 . . 4 6 4 1 5 1 0 0 . . 6 2 2 5 5 5 2 1 . . 5 0 2 4 3 7 1 3 0 .1 .1 0 0 0 0 4 0.440 3.255 12.254 2.750 10.146 0.770 0.327 1.580 5.816 2.350 8.641 0.450 1.659 1.000

1 0.416 3.265 12.008 1.250 4.285 0.710 0.343 1.816 6.733 2.526 9.403 0.785 2.863 7.100 1-Mar 2 3 0 0 . . 4 4 4 5 6 1 3 3 . . 5 3 5 5 5 5 1 1 3 1 . . 8 6 5 4 1 2 3 1 . . 0 7 0 5 0 0 1 6 1 .5 .9 9 7 5 2 0 1 . . 5 0 3 6 5 5 0 0 . . 3 2 0 7 6 0 1 1 . . 8 7 1 4 6 8 7 6 . . 3 2 5 5 5 2 2 2 . . 3 8 5 1 1 3 9 9 . . 5 9 0 8 1 7 0 0 . . 6 4 7 4 0 0 2 1 . . 6 5 5 6 8 9 10 1 1 .0 .2 0 5 0 0 4 0.454 2.677 10.538 1.000 3.891 1.310 0.354 1.904 7.550 3.214 12.930 1.073 4.178 55.733

1 0.000 4.66 0.75 1.52 1.66 0.29 0.86 1.90 1-Apr 2 3 0 0 . . 0 0 0 1 0 5 1 7 . . 9 2 9 3 0 0 0 1 . . 5 2 0 5 0 0 1 3 . . 4 0 1 5 5 5 1 0 . . 4 9 7 8 0 2 0 1 . . 4 9 3 1 6 0 1 1 . . 4 2 5 6 0 0 2 3 . . 0 2 0 5 0 0 4 0.336 4.650 0.500 1.100 1.462 0.343 0.760 1.800 1 0.700 3.505 0.750 1.420 1.745 0.28 1.54 1.90 1-May 2 3 0 0 . . 2 0 5 0 8 0 1 4 . . 0 1 0 4 0 5 1 1 . . 7 0 5 0 0 0 1 0 . . 4 8 6 4 0 5 1 1 . . 3 6 2 3 9 3 0 0 . . 1 1 8 0 3 0 2 1 . . 6 5 1 1 5 5 4 2 . . 5 6 0 0 0 0

4 0.379 3.243 1.000 0.848 1.723 0.132 1.448 4.300 1 1.094 1.989 1.185 1.267 1.730 0.119 1.165 1.000 1-Jun 2 3 0 0 . . 3 6 9 6 0 1 1 2 . . 4 5 6 4 5 5 1 0 . . 5 5 0 0 0 0 0 0 . . 7 8 3 8 0 0 2 1 . . 1 7 3 2 3 0 0 0 . . 1 1 2 0 0 0 1 0 . . 7 6 8 3 5 5 2 1 3 . . 5 0 0 0 0 0 2018 4 1 0 0 . . 2 4 3 0 5 7 1 4 . . 0 3 0 6 0 0 2 0 . . 0 5 0 0 0 0 1 1 . . 1 9 3 5 5 5 1 1 . . 9 2 3 1 0 1 0 0 . . 1 1 0 0 0 0 1 1 . . 4 3 6 8 5 0 4 6 . . 8 5 5 0 0 0

1-Jul 2 3 0 0 . . 6 6 5 2 5 4 3 1 . . 9 4 6 6 0 0 0 1 . . 5 2 0 5 0 0 1 1 . . 2 2 6 8 5 0 2 1 . . 1 4 6 6 8 6 0 0 . . 1 1 0 0 5 3 1 2 . . 5 2 7 8 5 0 1 1 6 . . 5 5 0 0 0 0 4 0.100 2.480 1.167 0.720 1.442 0.102 2.877 4.633 1 0.510 1.610 1.750 0.725 1.295 0.100 1.585 4.850 1-Aug 2 3 0 0 . . 4 6 8 4 3 1 1 2 . . 4 4 8 4 0 5 0 0 . . 1 7 0 5 0 0 1 0 . . 2 7 9 5 0 0 1 1 . . 1 0 4 0 2 6 0 0 . . 1 1 0 0 8 8 2 2 . . 0 0 5 5 0 0 6 1 . . 7 0 0 0 0 0

4 0.829 3.030 2.500 1.303 1.007 0.100 2.243 1.000 1 0.661 0.100 0.500 0.930 1.193 0.104 3.030 1.500 1-Sep 2 3 0 0 . . 0 6 0 7 0 9 4 4 . . 8 3 5 6 0 0 3 0 . . 0 5 0 0 0 0 0 0 . . 7 7 3 2 0 0 1 1 . . 5 3 8 1 4 0 0 0 . . 1 1 4 0 0 8 2 2 . . 6 3 5 4 0 0 3 4 . . 1 2 0 0 0 0 4 0.000 2.520 0.750 0.720 1.788 0.100 2.200 1.500 1 0.631 1.425 0.500 1.235 1.573 0.106 2.050 2.050 1-Oct 2 3 0 0 . . 1 3 4 5 1 3 3 2 . . 6 1 2 8 5 5 1 1 . . 5 7 0 5 0 0 0 0 . . 7 9 6 2 0 5 1 1 . . 5 6 7 1 5 5 0 0 . . 1 1 0 0 5 7 2 2 . . 4 0 5 1 0 5 1 3 . . 0 6 0 5 0 0

4 0.427 2.278 0.875 0.948 1.768 0.117 1.570 2.325 1 0.000 1.525 0.750 1.120 1.759 0.110 0.550 2.000 1-Nov 2 3 0 0 . . 0 4 7 9 7 8 1 2 . . 3 9 7 0 5 0 0 3 . . 5 5 0 0 0 0 1 0 . . 1 8 5 9 0 5 1 1 . . 9 9 8 7 0 3 3 2 . . 1 8 3 6 0 8 0 0 . . 1 1 2 0 5 0 1 0 . . 0 2 5 2 0 0 4 0.276 2.355 1.750 0.720 1.956 2.676 0.114 0.520 1 0.558 1.470 6.880 3.000 14.045 0.860 0.199 2.071 9.636 2.931 13.648 0.645 2.981 1.000

1-Dec 2 3 0 0 . . 5 7 5 5 4 8 2 2 . . 2 1 5 6 5 0 1 1 0 2 . . 1 6 4 0 6 9 0 1 . . 5 7 0 5 0 0 1 2 0 .2 .0 5 8 0 7 0 0 . . 7 7 9 2 0 0 0 0 . . 1 1 6 6 3 6 2 1 . . 8 8 9 7 1 8 1 1 3 1 . . 0 4 0 1 3 3 3 2 . . 6 5 8 9 1 8 1 1 6 5 . . 5 7 5 7 8 6 0 0 . . 3 2 1 6 5 0 1 1 . . 4 5 1 8 8 4 1 4 . . 0 2 0 5 0 0 4 0.730 4.383 #DIV/0! 2.833 #DIV/0! 0.837 0.205 1.627 #DIV/0! 2.464 #DIV/0! 0.233 #DIV/0! 1.000 1 0.735 2.400 #DIV/0! 0.500 #DIV/0! 0.720 0.259 1.722 #DIV/0! 2.442 #DIV/0! 0.205 #DIV/0! 6.050

1-Jan 2 3 0 0 . . 6 6 4 3 4 3 1 1 . . 7 7 4 4 5 0 # # D D I I V V / / 0 0 ! ! 0 3 . . 5 2 0 5 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 7 7 2 2 0 0 0 0 . . 3 2 8 8 5 0 2 1 . . 0 9 1 5 8 0 # # D D I I V V / / 0 0 ! ! 2 2 . . 7 6 3 7 8 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 4 4 6 0 5 0 # # D D I I V V / / 0 0 ! ! 1 1 . . 0 6 0 0 0 0 4 0.640 1.477 #DIV/0! 0.500 #DIV/0! 0.720 0.287 2.352 #DIV/0! 3.072 #DIV/0! 0.450 #DIV/0! 2.067

1 0.583 1.955 #DIV/0! 1.750 #DIV/0! 0.720 0.100 2.719 #DIV/0! 3.439 #DIV/0! 0.610 #DIV/0! 1.000 1-Feb 2 0.613 1.560 #DIV/0! 0.500 #DIV/0! 0.720 0.100 2.327 #DIV/0! 3.047 #DIV/0! 0.650 #DIV/0! 1.000 Stream Effluent Spray Effluent Flow BOD TSS TKN Ammonia NO2 + NO3 Total Nitrogen-N TP Ge E o . m Co e l a i n Flow BOD TSS TKN NO2 + NO3 Ammonia TP E. Coli Year M1-oFnetbh We 3 ek 0

M

.6

G

2

D

3 1 m .8 g 8

/L

0 # lb

D

s

I

/

V

d / a 0 y ! 0 m .5 g 0

/L

0 # lb

D

s

I

/

V

d / a 0 y ! 0 m .7 g 9

/L

0 0 m .1 g 2

/L

9 2 m .3 g 7

/L

5 # lb

D

s

I

/

V

d / a 0 y ! 3 m .1 g 6

/L

5 # lb

D

s

I

/

V

d / a 0 y ! 0 m .5 g 6

/L

0 # lb

D

s

I

/

V

d / a 0 y !

MPN

1 / .0 1 0 0 0 0 ml MGD mg/L mg/L mg/L mg/L mg/L mg/L MPN/100 ml 4 0.645 1.903 #DIV/0! 1.333 #DIV/0! 0.720 0.232 2.901 #DIV/0! 3.621 #DIV/0! 0.757 #DIV/0! 1.000 1 0.729 2.720 #DIV/0! 2.000 #DIV/0! 0.720 0.259 2.342 #DIV/0! 3.062 #DIV/0! 0.640 #DIV/0! 100.750 1-Mar 2 3 0 0 . . 6 6 6 1 7 4 2 2 . . 6 5 7 7 5 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 5 0 0 0 0 # # D D I I V V / / 0 0 ! ! 0 1 . . 8 1 2 2 0 0 0 0 . . 1 3 7 8 3 0 1 1 . . 5 3 9 3 1 1 # # D D I I V V / / 0 0 ! ! 2 2 . . 4 4 1 5 1 1 # # D D I I V V / / 0 0 ! ! 0 0 . . 6 2 4 4 0 0 # # D D I I V V / / 0 0 ! ! 1 1 . . 5 0 0 0 0 0

4 0.624 3.165 #DIV/0! 1.000 #DIV/0! 0.855 0.394 1.549 #DIV/0! 2.404 #DIV/0! 0.295 #DIV/0! 1.000 1 0.525 1.860 0.750 0.720 1.287 2.007 0.251 0.225 1-Apr 2 3 0 0 . . 5 3 4 5 6 6 1 1 . . 6 3 2 9 0 0 0 0 . . 5 7 0 5 0 0 0 0 . . 7 8 5 0 0 0 1 1 . . 4 8 0 9 7 0 2 2 . . 1 6 5 9 7 0 0 0 . . 2 2 3 6 3 0 0 0 . . 2 6 8 8 0 0 4 0.390 1.677 1.000 1.250 1.972 3.222 0.351 1.030 1 0.111 1.435 0.500 0.910 2.106 3.016 0.285 1.865

1-May 2 3 0 0 . . 0 5 5 0 3 2 1 1 . . 2 2 4 7 5 0 0 0 . . 5 5 0 0 0 0 0 0 . . 7 7 2 2 0 0 1 2 . . 8 3 1 9 4 2 2 3 . . 5 1 3 1 4 2 0 0 . . 1 2 7 3 1 2 1 1 . . 8 9 3 6 0 5 4 0.086 1.090 0.500 0.987 1.745 2.732 0.194 1.387 1 0.038 1.135 0.500 0.930 2.488 3.418 0.297 1.615 1-Jun 2 3 0 0 . . 1 6 4 1 7 4 1 1 . . 3 0 9 1 5 5 1 0 . . 2 5 5 0 0 0 1 0 . . 9 8 0 3 0 5 1 1 . . 9 2 9 7 6 1 3 2 . . 8 1 9 0 6 6 0 0 . . 1 1 9 2 1 1 1 1 . . 0 4 7 6 5 5

2019 4 1 0 0 . . 5 3 2 3 3 0 1 1 . . 1 0 5 0 5 0 0 0 . . 5 5 0 0 0 0 0 0 . . 8 8 8 5 5 0 1 1 . . 4 1 0 5 3 6 2 2 . . 2 0 8 0 8 6 0 0 . . 1 1 1 0 3 0 2 2 . . 0 2 3 1 5 5 1-Jul 2 3 0 0 . . 7 6 1 6 3 3 1 1 . . 6 0 1 1 0 0 0 0 . . 3 7 0 5 0 0 1 0 . . 1 7 8 9 0 0 1 1 . . 1 2 8 2 6 7 2 2 . . 3 0 6 1 6 7 0 0 . . 1 3 0 9 0 1 2 2 . . 4 9 8 0 0 0 4 0.854 1.175 0.500 0.720 1.144 1.864 0.130 2.563 1 0.681 1.295 0.500 0.720 1.289 2.009 0.120 1.950

1-Aug 2 3 0 0 . . 4 6 8 4 0 1 1 1 . . 0 5 5 1 0 5 0 2 . . 5 2 0 5 0 0 1 1 . . 9 0 7 0 0 0 1 1 . . 4 5 5 0 5 0 3 2 . . 4 5 2 0 5 0 0 0 . . 1 1 1 0 0 0 1 1 . . 3 2 4 9 0 5 4 0.411 1.070 0.500 0.860 1.615 2.475 0.100 1.980 1 0.412 1.030 0.500 1.000 1.558 2.558 0.100 1.860 1-Sep 2 3 0 0 . . 4 5 7 3 1 7 1 1 . . 0 0 0 8 0 5 0 0 . . 5 5 0 0 0 0 1 1 . . 0 0 0 0 0 0 1 1 . . 7 5 5 0 8 0 2 2 . . 7 5 5 0 8 0 0 0 . . 1 1 0 1 0 1 1 1 . . 7 9 0 6 0 5

4 0.304 1.115 0.750 1.000 1.659 2.659 0.121 1.905 1 0.221 1.230 1.000 1.000 1.437 2.536 0.195 1.537 1-Oct 2 3 0 0 . . 0 0 9 3 0 6 1 1 . . 0 0 1 0 0 0 0 0 . . 5 5 0 0 0 0 1 1 . . 0 0 0 0 0 0 1 1 . . 7 4 9 5 9 5 2 2 . . 7 4 9 9 9 8 0 0 . . 1 1 1 5 1 7 2 1 . . 2 7 5 5 0 0 4 0.032 1.103 0.625 1.000 1.868 2.868 0.337 1.950 1 0.265 1.355 1.250 1.000 1.317 2.317 0.100 1.620 1-Nov 2 3 0 0 . . 1 5 1 0 1 9 1 1 . . 2 0 8 8 0 5 0 0 . . 5 5 0 0 0 0 1 1 . . 0 0 0 0 0 0 1 1 . . 4 4 1 4 1 7 2 2 . . 4 4 1 4 1 7 0 0 . . 1 1 4 8 2 6 1 1 . . 5 2 3 8 5 0

4 0.194 2.520 0.750 0.790 0.922 1.712 0.295 0.970 1 0.442 1.840 #DIV/0! 0.750 #DIV/0! 0.500 0.145 0.873 #DIV/0! 1.373 #DIV/0! 1.535 #DIV/0! 1.500 1-Dec 2 3 0 0 . . 4 3 5 9 5 6 1 2 . . 7 3 2 2 0 5 # # D D I I V V / / 0 0 ! ! 0 0 . . 7 5 5 0 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 6 7 8 3 5 0 0 . . 2 8 8 8 5 9 1 0 . . 5 8 2 6 4 2 # # D D I I V V / / 0 0 ! ! 2 1 . . 0 5 9 4 6 7 # # D D I I V V / / 0 0 ! ! 1 0 . . 9 9 8 5 5 0 # # D D I I V V / / 0 0 ! ! 1 2 0 0 2 0 . . 3 5 5 0 0 0

4 0.412 1.177 #DIV/0! 0.833 #DIV/0! 0.500 0.161 0.816 #DIV/0! 1.316 #DIV/0! 0.377 #DIV/0! 72.000 1 0.415 1.535 #DIV/0! 0.750 #DIV/0! 0.500 0.415 0.878 #DIV/0! 1.378 #DIV/0! 0.630 #DIV/0! 2.600 1-Jan 2 3 0 0 . . 4 4 5 1 0 3 1 1 . . 2 0 9 0 5 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 7 0 5 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 5 0 6 0 8 0 0 . . 2 2 6 2 9 1 1 1 . . 1 0 6 2 4 9 # # D D I I V V / / 0 0 ! ! 1 1 . . 6 5 6 9 4 6 # # D D I I V V / / 0 0 ! ! 0 0 . . 4 9 6 5 5 0 # # D D I I V V / / 0 0 ! ! 10 4 1 .2 .2 0 5 0 0

4 0.441 1.530 #DIV/0! 0.500 #DIV/0! 0.500 0.226 1.383 #DIV/0! 1.883 #DIV/0! 0.753 #DIV/0! 2.367 1 0.457 1.595 #DIV/0! 0.500 #DIV/0! 0.500 0.211 1.254 #DIV/0! 1.754 #DIV/0! 0.965 #DIV/0! 12.100 1-Feb 2 3 0 0 . . 4 4 7 6 4 6 2 1 . . 9 9 2 4 0 5 # # D D I I V V / / 0 0 ! ! 1 0 . . 2 5 5 0 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 6 7 7 0 5 0 0 . . 5 5 5 7 7 7 1 1 . . 3 2 0 7 3 9 # # D D I I V V / / 0 0 ! ! 1 1 . . 8 9 7 5 3 4 # # D D I I V V / / 0 0 ! ! 1 0 . . 3 8 3 6 5 5 # # D D I I V V / / 0 0 ! ! 1 2 0 0 1 0 . . 2 5 5 0 0 0

4 0.402 3.265 #DIV/0! 0.500 #DIV/0! 0.730 0.379 1.128 #DIV/0! 1.858 #DIV/0! 1.050 #DIV/0! 200.500 1 0.448 2.010 #DIV/0! 0.500 #DIV/0! 0.690 0.538 1.094 #DIV/0! 1.784 #DIV/0! 0.830 #DIV/0! 200.500 1-Mar 2 3 0 0 . . 4 4 4 4 5 4 1 1 . . 6 9 1 8 5 0 # # D D I I V V / / 0 0 ! ! 0 1 . . 7 7 5 5 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 9 0 0 0 3 0 0 . . 4 5 8 0 4 1 1 0 . . 0 9 4 3 9 2 # # D D I I V V / / 0 0 ! ! 1 1 . . 5 8 4 3 9 5 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 9 1 5 5 0 # # D D I I V V / / 0 0 ! ! 10 1 0 .0 .7 0 5 0 0

4 0.470 2.177 #DIV/0! 0.500 #DIV/0! 0.878 0.555 0.920 #DIV/0! 1.798 #DIV/0! 0.967 #DIV/0! 200.500 1 0.376 1.640 1.750 0.848 5.136 5.983 0.443 1.635 1-Apr 2 3 0 0 . . 0 0 0 5 0 6 1 1 . . 4 5 7 3 0 5 1 0 . . 2 7 5 5 0 0 0 0 . . 5 5 6 3 8 5 1 1 . . 5 4 6 4 2 5 1 1 . . 7 9 7 8 9 0 0 0 . . 3 2 0 9 9 1 1 2 . . 4 1 5 6 0 0 4 0.096 1.310 1.833 0.617 1.592 2.209 0.277 1.390 1 0.020 1.640 1.500 0.500 1.545 2.045 0.218 1.915

1-May 2 3 0 0 . . 4 5 1 1 6 4 1 1 . . 6 4 8 0 5 0 1 1 . . 0 2 0 5 0 0 4 0 . . 0 5 9 8 0 8 0 1 . . 4 1 7 2 8 0 4 1 . . 5 7 6 0 8 7 3 0 . . 4 2 2 1 0 5 1 0 . . 8 8 3 8 0 5 4 0.082 2.100 0.500 0.500 1.238 1.738 0.260 2.015 1 0.419 1.170 1.500 0.500 1.210 1.710 0.248 1.770 1-Jun 2 3 0 0 . . 4 3 5 6 6 5 1 1 . . 0 6 8 5 5 0 0 0 . . 5 5 0 0 0 0 4 2 . . 7 0 7 8 0 0 1 0 . . 0 8 9 6 3 3 5 2 . . 8 9 6 4 3 3 0 0 . . 3 2 1 2 0 9 2 1 . . 5 7 3 6 5 5

2020 4 1 0 0 . . 6 3 7 7 6 4 1 1 . . 4 5 0 6 0 0 0 1 . . 6 5 6 0 7 0 0 0 . . 9 5 5 0 8 0 0 1 . . 9 0 9 2 1 4 1 1 . . 9 5 5 2 0 4 0 0 . . 1 1 6 2 6 6 2 2 . . 6 5 2 0 0 0 1-Jul 2 3 0 0 . . 3 7 9 3 1 4 1 1 . . 0 2 9 7 0 0 1 0 . . 5 5 0 0 0 0 0 0 . . 5 5 0 0 0 0 1 1 . . 2 3 6 5 6 6 1 1 . . 7 8 6 5 6 6 0 0 . . 1 3 7 3 5 3 2 2 . . 3 4 8 0 0 0 4 0.330 1.323 0.667 0.798 1.496 2.033 0.471 1.870 1 0.000 1.945 0.750 1.313 3.542 4.854 0.391 2.950

1-Aug 2 3 0 0 . . 4 1 7 9 7 0 2 1 . . 8 1 0 6 5 0 0 0 . . 7 5 5 0 0 0 1 0 . . 0 9 1 9 8 0 1 1 . . 3 8 1 6 7 3 2 2 . . 3 8 3 5 5 3 1 0 . . 3 2 0 4 3 7 2 2 . . 5 6 1 3 5 0 4 0.609 1.665 0.500 0.823 1.793 2.615 0.169 2.420 1 0.304 1.900 0.500 1.393 1.612 3.004 0.154 1.730 1-Sep 2 3 0 0 . . 3 5 1 7 1 9 1 1 . . 9 0 7 9 0 5 0 0 . . 5 7 0 5 0 0 0 0 . . 9 5 0 0 5 0 1 1 . . 9 5 0 0 4 2 2 2 . . 8 0 0 0 9 2 0 0 . . 1 1 4 8 9 9 1 1 . . 6 6 8 8 5 5

4 0.544 1.920 1.125 0.521 1.358 1.880 0.166 1.303 1 0.188 2.900 0.500 0.500 1.167 1.667 0.254 1.180 1-Oct 2 3 0 0 . . 2 4 0 6 3 6 3 2 . . 3 4 8 6 5 0 0 0 . . 5 7 0 5 0 0 0 0 . . 5 6 0 9 0 5 1 1 . . 0 4 1 3 0 6 1 2 . . 5 1 1 3 0 1 0 0 . . 2 2 7 3 6 8 0 1 . . 8 4 6 8 5 5 4 0.404 2.015 0.500 0.533 1.147 1.679 0.409 1.635 1 0.726 1.305 0.500 0.500 1.273 1.773 0.462 1.935 1-Nov 2 3 0 0 . . 3 8 4 0 9 5 1 3 . . 3 3 4 1 5 0 0 0 . . 5 7 0 5 0 0 0 0 . . 5 5 0 0 0 0 1 1 . . 2 2 3 6 3 4 1 1 . . 7 7 3 6 3 5 0 0 . . 3 3 7 6 7 2 1 1 . . 4 5 8 8 0 5

4 0.277 2.255 0.500 2.853 1.435 3.788 0.519 1.135 1 0.701 1.550 #DIV/0! 1.250 #DIV/0! 2.293 0.427 1.190 #DIV/0! 3.482 #DIV/0! 0.785 #DIV/0! 20.150 1-Dec 2 3 0 0 . . 6 7 5 5 8 3 1 1 . . 8 8 1 0 0 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 5 5 0 0 0 0 # # D D I I V V / / 0 0 ! ! 2 2 . . 8 7 5 7 5 0 0 0 . . 5 4 2 4 1 1 1 1 . . 2 7 8 0 3 3 # # D D I I V V / / 0 0 ! ! 4 4 . . 1 4 3 7 8 3 # # D D I I V V / / 0 0 ! ! 0 1 . . 8 3 1 3 5 5 # # D D I I V V / / 0 0 ! ! 1 7 6 6 4 . . 1 6 0 0 0 0

4 0.731 1.897 #DIV/0! 1.500 #DIV/0! 4.867 0.300 1.668 #DIV/0! 6.534 #DIV/0! 0.857 #DIV/0! 381.300 1 0.778 1.515 #DIV/0! 1.500 #DIV/0! <1.0 0.275 1.762 #DIV/0! 2.262 #DIV/0! 1.165 #DIV/0! 1.000 1-Jan 2 3 0 0 . . 7 6 1 9 7 9 1 1 . . 3 8 7 1 5 5 # # D D I I V V / / 0 0 ! ! 3 3 . . 0 5 0 0 0 0 # # D D I I V V / / 0 0 ! ! 0 < .5 1 1 .0 0 0 0 . . 3 4 9 3 7 0 1 1 . . 9 8 5 1 7 9 # # D D I I V V / / 0 0 ! ! 2 2 . . 7 8 1 1 2 9 # # D D I I V V / / 0 0 ! ! 1 0 . . 0 9 0 0 0 0 # # D D I I V V / / 0 0 ! ! 1 < .0 1 0 .0 0

4 0.634 1.460 #DIV/0! 1.000 #DIV/0! 1.030 0.192 2.134 #DIV/0! 3.149 #DIV/0! 0.715 #DIV/0! <1.0 1 0.644 1.370 #DIV/0! <0.5 #DIV/0! 1.020 0.187 2.005 #DIV/0! 3.025 #DIV/0! 0.900 #DIV/0! <1.0 1-Feb 2 3 0 0 . . 6 6 3 7 4 6 1 1 . . 4 6 9 0 0 5 # # D D I I V V / / 0 0 ! ! 1 2 . . 0 0 0 0 0 0 # # D D I I V V / / 0 0 ! ! 1 < .0 1 5 .0 0 0 0 . . 2 1 2 5 5 6 2 3 . . 3 2 9 6 6 8 # # D D I I V V / / 0 0 ! ! 3 4 . . 3 2 9 9 6 3 # # D D I I V V / / 0 0 ! ! 0 0 . . 8 7 5 3 0 5 # # D D I I V V / / 0 0 ! ! 1 1 0 2 8 1 2 3 . . 1 5 5 0 0 0

4 0.743 1.640 #DIV/0! 1.000 #DIV/0! <1.0 0.296 2.475 #DIV/0! 3.475 #DIV/0! 0.455 #DIV/0! <1.0 1 0.799 <1.0 #DIV/0! 20.500 #DIV/0! <1.0 0.314 2.148 #DIV/0! 3.148 #DIV/0! 0.360 #DIV/0! <1.0 1-Mar 2 3 0 0 . . 6 6 9 5 3 1 2 1 . . 0 1 6 7 5 0 # # D D I I V V / / 0 0 ! ! < < 0 0 . . 5 5 # # D D I I V V / / 0 0 ! ! 2 < .1 1 5 .0 5 1 0 . . 4 2 3 0 8 0 1 1 . . 7 7 1 7 5 6 # # D D I I V V / / 0 0 ! ! 3 2 . . 8 7 7 7 0 6 # # D D I I V V / / 0 0 ! ! 0 0 . . 4 1 0 0 0 5 # # D D I I V V / / 0 0 ! ! 121 <1 0. .0 300

4 0.651 1.580 #DIV/0! 1.500 #DIV/0! 1.910 0.273 1.886 #DIV/0! 3.190 #DIV/0! 0.157 #DIV/0! 7.750 1 0.628 2.607 <0.5 1.350 1.593 0.265 0.340 4.650 1-Apr 2 3 0 0 . . 5 5 6 4 9 2 2 2 . . 5 2 3 2 0 0 1 < . 0 0 . 0 5 0 1 0 . . 3 9 0 7 0 0 2 2 . . 1 1 9 2 4 5 0 0 . . 7 1 8 7 0 0 0 0 . . 2 1 9 7 5 0 1 3 1 . . 1 5 0 5 0 0 4 0.540 2.995 2.500 2.420 2.065 1.010 0.860 2419.600 1 0.503 2.740 1.500 1.950 2.015 0.523 2.550 <1.0

1-May 2 3 0 0 . . 4 4 7 6 7 8 2 3 . . 3 2 5 3 0 0 1 < . 0 5 . 0 5 0 1 2 . . 6 7 2 7 0 5 2 2 . . 4 6 6 1 0 5 0 0 . . 6 4 5 5 5 7 2 2 . . 1 1 0 0 0 0 1 < . 1 0 . 0 0 0 4 0.468 2.970 <0.5 2.405 3.085 0.572 2.900 <1.0 1 0.457 2.900 <0.5 1.445 2.835 0.217 1.900 1.000 1-Jun 2 3 0 0 . . 4 4 5 3 3 8 2 2 . . 9 5 2 5 0 0 < < 0 0 . . 5 5 1 0 . . 1 4 4 5 5 5 2 2 . . 5 6 4 4 5 5 0 0 . . 1 1 5 4 6 3 2 2 . . 1 2 7 0 0 0 < < 1 1 . . 0 0

4 0.438 3.175 3.000 1.338 2.853 0.224 2.643 <1.0 1 0.443 2.380 <0.5 1.210 2.145 0.186 1.715 1.000 1-Jul 2 3 0 0 . . 4 4 1 1 5 8 2 2 . . 3 2 8 4 0 0 < < 0 0 . . 5 5 1 < . 1 2 . 8 0 0 2 3 . . 2 0 1 8 5 5 0 0 . . 2 2 6 0 2 9 1 1 . . 0 9 8 2 0 0 2 < . 1 7 . 9 0 5 4 0.398 2.930 <0.5 <1.0 3.495 0.215 2.120 1.000 1 0.408 3.215 <0.5 1.255 1.390 0.374 0.700 <1.0 1-Aug 2 3 0 0 . . 4 4 1 3 6 4 4 5 . . 1 3 9 5 5 0 2 1 . . 0 0 0 0 0 0 1 9 . . 6 9 2 0 0 0 0 1 . . 8 8 5 4 5 5 0 8 . . 5 7 9 9 9 0 0 0 . . 7 4 8 0 5 5 14 < 3 1 . . 7 0 00

4 0.420 2.583 3.000 1.923 2.093 0.154 1.357 3.767 1 0.412 1.660 <0.5 1.320 2.000 0.165 1.450 3.100 Stream Effluent Spray Effluent Flow BOD TSS TKN Ammonia NO2 + NO3 Total Nitrogen-N TP Ge E o . m Co e l a i n Flow BOD TSS TKN NO2 + NO3 Ammonia TP E. Coli Year Month Week MGD mg/L lbs/day mg/L lbs/day mg/L mg/L mg/L lbs/day mg/L lbs/day mg/L lbs/day MPN/100 ml MGD mg/L mg/L mg/L mg/L mg/L mg/L MPN/100 ml

1-Sep 2 3 0 0 . . 4 4 2 1 1 2 1 1 . . 8 5 5 8 0 5 1 < . 0 0 . 0 5 0 1 < . 1 1 . 2 0 0 2 2 . . 2 1 6 4 5 5 0 0 . . 1 1 6 7 0 0 1 1 . . 3 4 6 1 5 0 3 < . 1 1 . 0 0 0 4 0.441 1.533 <0.5 <1.0 1.997 0.166 1.737 1.000 1 0.400 1.460 <0.5 <1.0 1.840 0.218 2.100 <1.0 1-Oct 2 3 0 0 . . 4 3 0 9 1 7 1 1 . . 9 2 1 8 0 0 2 < . 0 0 . 0 5 0 1 1 . . 0 4 7 5 0 0 1 1 . . 4 5 3 6 5 5 0 0 . . 2 2 1 7 9 4 1 1 . . 5 4 6 8 5 5 >2 < 4 1 1 . 9 0 .6

4 0.431 1.320 1.000 1.370 1.395 0.348 2.185 1210.300 1 0.413 1.455 <0.5 2.070 0.950 0.381 1.765 <1.0 1-Nov 2 3 0 0 . . 4 3 0 9 6 3 1 1 . . 3 3 0 0 0 0 < < 0 0 . . 5 5 2 2 . . 2 9 7 8 0 5 1 0 . . 5 8 6 1 0 5 0 0 . . 3 4 6 1 6 6 2 1 . . 6 4 0 6 0 5 5 < . 1 2 . 0 0 0 4 0.428 1.365 1.000 1.840 0.760 0.474 0.977 <1.0 1 0.472 1.435 #DIV/0! 1.000 #DIV/0! 2.155 0.808 0.785 #DIV/0! 2.940 #DIV/0! 1.000 #DIV/0! <1.0

1-Dec 2 3 0 0 . . 4 4 4 2 3 4 1 1 . . 8 6 5 2 5 0 # # D D I I V V / / 0 0 ! ! < < 0 0 . . 5 5 # # D D I I V V / / 0 0 ! ! 1 1 . . 4 4 7 3 0 5 0 0 . . 7 8 9 1 2 9 0 0 . . 9 9 1 6 5 5 # # D D I I V V / / 0 0 ! ! 2 2 . . 6 4 9 0 5 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 9 7 3 0 5 0 # # D D I I V V / / 0 0 ! ! 1 < .0 1 0 .0 0 4 0.439 2.340 #DIV/0! 1.000 #DIV/0! 2.527 1.078 0.817 #DIV/0! 3.343 #DIV/0! 0.767 #DIV/0! 1.000

1 0.468 1.555 #DIV/0! <0.5 #DIV/0! 1.825 0.551 1.470 #DIV/0! 3.295 #DIV/0! 0.510 #DIV/0! <1.0 1-Jan 2 3 0 0 . . 4 4 5 8 8 4 1 1 .5 .2 9 9 5 # # D D I I V V / / 0 0 ! ! < < 0 0 . . 5 5 # # D D I I V V / / 0 0 ! ! 1 3 .9 .4 7 2 5 0 0 . . 5 6 4 5 8 9 5 5 1 0 . . 0 9 5 2 # # D D I I V V / / 0 0 ! ! 2 4 . . 8 4 9 7 5 # # D D I I V V / / 0 0 ! ! 0 0 . . 6 7 # # D D I I V V / / 0 0 ! ! < < 1 1 . . 0 0 4 0.425 1.895 #DIV/0! 1 #DIV/0! 1.81 0.854 1.007 #DIV/0! 2.817 #DIV/0! 0.78 #DIV/0! <1.0

1 0.479 1.400 #DIV/0! 1.000 #DIV/0! 1.450 0.630 0.845 #DIV/0! 2.295 #DIV/0! 0.795 #DIV/0! 5.400 1-Feb 2 3 0 0 . . 4 4 3 3 4 0 1 1 . . 8 4 5 8 0 0 # # D D I I V V / / 0 0 ! ! < < 0 0 . . 5 5 # # D D I I V V / / 0 0 ! ! 1 1 . . 4 4 3 6 0 0 0 0 . . 6 7 0 2 4 6 0 0 . . 4 7 4 1 5 0 # # D D I I V V / / 0 0 ! ! 1 2 . . 8 1 7 7 5 0 # # D D I I V V / / 0 0 ! ! 0 0 . . 6 6 1 0 5 0 # # D D I I V V / / 0 0 ! ! < < 1 1 . . 0 0

4 0.447 4.093 #DIV/0! 2.333 #DIV/0! 1.923 1.043 0.633 #DIV/0! 2.557 #DIV/0! 1.043 #DIV/0! 1.000 1 0.431 5.380 #DIV/0! 2.000 #DIV/0! 1.830 1.080 1.255 #DIV/0! 3.085 #DIV/0! 0.850 #DIV/0! <1.0 1-Mar 2 3 0 0 . . 4 4 4 5 9 5 3 3 . . 6 6 9 3 0 5 # # D D I I V V / / 0 0 ! ! 2 < .0 0 0 .5 0 # # D D I I V V / / 0 0 ! ! 1 1 . . 6 4 2 9 0 0 0 0 . . 8 7 7 3 0 0 1 1 . . 3 2 8 9 0 5 # # D D I I V V / / 0 0 ! ! 3 2 . . 0 7 0 8 0 5 # # D D I I V V / / 0 0 ! ! 1 1 . . 1 0 0 5 0 0 # # D D I I V V / / 0 0 ! ! 1 2 . . 0 0 0 0 0 0

4 0.421 3.193 #DIV/0! 4.500 #DIV/0! 1.460 0.653 1.270 #DIV/0! 2.730 #DIV/0! 0.920 #DIV/0! 1210.300 1 0.446 2.730 3.000 1.445 1.285 0.880 0.930 1.000 1-Apr 2 3 0 0 . . 4 4 2 1 1 9 1 1 . . 5 3 5 3 5 0 2 < . 0 0 . 0 5 0 1 < . 1 0 . 2 0 0 1 0 . . 4 9 5 3 0 0 0 0 . . 4 3 8 0 5 1 1 0 . . 3 9 5 5 0 0 121 <1 0. .0 300 4 0.399 1.945 2.000 <1.0 0.510 0.145 1.700 2.000 1 0.418 1.820 <0.5 1.225 0.915 0.442 3.000 307.600

1-May 2 3 0 0 . . 4 4 0 1 2 2 3 3 . . 0 5 9 7 0 0 < < 0 0 . . 5 5 1 1 . . 2 4 8 5 0 0 0 0 . . 4 1 7 3 5 0 0 0 . . 5 6 2 9 7 3 2 2 . . 1 2 7 0 0 0 34 < 6 1 . . 0 0 00 4 0.430 2.587 3.000 1.920 0.443 0.687 2.490 4.100 1 0.391 2.580 4.000 1.975 0.520 0.556 2.515 1.000 1-Jun 2 3 0 0 . . 3 3 9 8 8 5 2 3 . . 7 1 5 8 5 0 < < 0 0 . . 5 5 1 1 . . 4 1 1 3 5 0 0 0 . . 5 7 6 8 5 5 0 0 . . 7 4 0 2 3 3 2 2 . . 6 7 3 3 0 0 12 1 1 . 0 0 . 0 3 0 00

4 0.400 2.207 1.000 1.205 0.703 0.209 2.620 1.000 1 0.391 1.380 <0.5 1.260 1.130 0.270 3.330 1.000 1-Jul 2 3 0 0 . . 4 4 1 2 7 0 1 1 . . 4 9 1 2 0 5 5 2 . . 0 0 0 0 0 0 1 1 . . 1 0 6 4 0 0 1 1 . . 3 5 9 5 0 5 0 0 . . 2 3 8 3 7 6 3 2 . . 0 8 4 1 0 5 < < 1 1 . . 0 0 4 0.392 1.875 1.000 <1.0 1.480 0.264 2.665 <1.0 1 0.391 1.445 <0.5 <1.0 2.515 0.218 3.015 1222.750 1-Aug 2 3 0 0 . . 3 3 8 5 4 1 1 1 . . 4 4 8 4 0 5 < < 0 0 . . 5 5 1 1 . . 1 2 4 2 0 0 1 6 . . 6 3 7 7 0 5 0 0 . . 1 1 5 2 6 4 4 3 . . 1 6 5 2 0 0 < < 1 1 . . 0 0

4 0.353 1.687 4.500 1.110 3.383 0.164 3.700 1210.300 1 0.367 2.065 <0.5 <1.0 4.555 <0.1 1.835 <1.0 1-Sep 2 3 0 0 . . 3 3 6 5 9 2 2 2 . . 0 9 5 1 0 0 2 1 . . 0 0 0 0 0 0 1 < . 1 6 . 7 0 0 4 2 . . 6 4 1 3 0 5 < < 0 0 . . 1 1 2 3 . . 8 0 5 0 0 0 3 < . 1 0 . 0 0 0 4 0.352 1.745 1.000 <1.0 2.265 0.122 2.250 353.800 1 0.413 1.615 1.000 <1.0 2.450 0.127 0.783 42.800 1-Oct 2 3 0 0 . . 3 3 8 8 1 4 1 1 . . 9 5 4 5 5 0 1 < . 0 5 . 0 5 0 1 < . 1 0 . 3 0 0 2 1 . . 1 7 3 9 5 0 < < 0 0 . . 1 1 2 2 . . 1 7 0 5 0 0 1 < . 1 0 . 0 0 0

4 0.404 1.560 <0.5 <1.0 2.450 <0.1 2.470 <1.0 1 0.391 - - - - - - <1.0 1-Nov 2 3 0 0 . . 3 3 7 9 1 0 1 1 . . 5 4 1 9 0 0 2 < . 0 0 . 0 5 0 < < 1 1 . . 0 0 1 1 . . 5 4 8 2 0 0 < < 0 0 . . 1 1 0 0 . . 3 8 3 3 3 3 < < 1 1 . . 0 0 4 0.378 1.640 2.000 <1.0 1.565 0.106 1.235 <1.0 1 0.476 1.130 #DIV/0! 1.000 #DIV/0! 1.030 0.149 2.435 #DIV/0! 2.950 #DIV/0! 2.420 #DIV/0! <1.0 1-Dec 2 3 0 0 . . 4 5 4 3 0 9 1 1 . . 5 1 0 5 5 0 # # D D I I V V / / 0 0 ! ! < < 0 0 . . 5 5 # # D D I I V V / / 0 0 ! ! 1 < .0 1 4 .0 0 0 0 . . 1 2 7 2 3 3 2 2 . . 0 1 3 2 0 5 # # D D I I V V / / 0 0 ! ! 2 2 . . 5 1 5 2 0 5 # # D D I I V V / / 0 0 ! ! 2 1 . . 7 1 8 8 5 4 # # D D I I V V / / 0 0 ! ! 1 < .0 1 0 .0 0

4 0.508 1.195 #DIV/0! 1.000 #DIV/0! 1.150 0.170 2.863 #DIV/0! 3.247 #DIV/0! 2.163 #DIV/0! 1613.400 2014-2022 Max 0.799 9.000 #DIV/0! 20.500 #DIV/0! 4.867 3.510 3.608 #DIV/0! 6.690 #DIV/0! 2.785 #DIV/0! 1613.400 1.094 7.230 6.075 9.900 6.375 8.790 4.150 2419.600 Average 0.469 2.635 #DIV/0! 1.913 #DIV/0! 1.061 0.361 1.730 #DIV/0! 2.772 #DIV/0! 0.558 #DIV/0! 77.370 0.383 2.238 1.448 1.171 1.702 1.167 1.243 63.835

Min 0.303 1.000 #DIV/0! 0.500 #DIV/0! 0.333 0.100 0.445 #DIV/0! 1.316 #DIV/0! 0.069 #DIV/0! 1.000 0.000 0.100 0.100 0.336 0.130 0.100 0.100 0.220 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report Centreville, MD Data 2: Operating Effluent Annual Spreadsheet Stream Effluent Spray Effluent Total Flow Calendar Flow BOD TSS TKN Ammonia NO2 + NO3 Total Nitrogen-N TP Geom Co e l a i n E. Flow BOD TSS TKN NO2 + NO3 Nitr T o o g t e a n l -N Ammonia TP Geom Co e l a i n E.

Year MGD mg/L lbs/day mg/L lbs/day mg/L mg/L mg/L lbs/day mg/L lbs/day mg/L lbs/day MPN/100 ml MGD mg/L mg/L mg/L mg/L mg/L mg/L mg/L MPN/100 ml MGD 2014 0.34 4.19 12.17 3.53 10.08 1.20 0.50 2.09 5.97 3.29 9.45 0.25 0.76 1.28 0.25 2.72 4.22 0.82 2.28 3.10 0.22 0.79 3.54 0.58 2015 0.38 3.15 9.92 1.31 3.91 0.71 0.14 1.89 6.13 2.61 8.37 0.18 0.57 4.52 0.25 3.87 3.03 0.85 1.62 2.31 0.18 1.13 2.72 0.63

2016 0.45 2.15 7.87 1.21 4.57 0.45 0.17 2.32 8.44 2.76 10.13 0.21 0.76 4.80 0.25 3.44 1.57 0.81 1.58 2.39 0.23 2.02 2.57 0.70 2017 0.38 2.50 7.88 1.77 5.48 0.85 0.20 1.46 4.60 2.32 7.29 0.46 1.43 1.22 0.21 3.17 1.52 0.90 1.42 2.30 0.16 1.82 5.99 0.59 2018 0.49 3.44 12.27 2.80 10.26 1.13 0.37 1.72 6.74 2.91 11.36 0.45 1.82 20.59 0.36 2.76 1.17 1.09 1.58 2.63 0.19 1.68 3.69 0.84 2019 0.59 2.02 9.917 0.99 4.836 0.72 0.28 1.83 8.985 2.55 12.511 0.66 3.241 31.31 0.37 1.27 0.67 0.98 1.58 2.56 0.18 1.67 5.22 0.96

2020 0.51 1.87 7.992 0.79 3.358 1.34 0.41 1.21 5.186 2.55 10.906 0.88 3.750 117.81 0.37 1.76 0.86 1.00 1.50 2.46 0.40 1.84 7.64 0.88 2021 0.59 1.63 8.052 2.84 14.036 1.86 0.54 1.63 8.063 3.15 15.528 0.68 3.348 461.08 0.45 2.41 1.89 1.96 2.03 3.77 0.57 1.58 236.15 1.04 2022 0.46 2.40 9.166 2.08 7.940 1.74 0.63 1.39 5.301 2.82 10.799 1.16 4.428 2.40 0.39 2.06 2.35 1.37 1.83 2.71 0.37 2.43 234.03 0.85

2014-2022 Max 0.588 4.187 12.274 3.529 10.261 1.338 0.500 2.319 8.985 3.287 12.511 0.877 3.750 117.814 0.368 3.869 4.221 1.091 2.275 3.097 0.399 2.021 7.643 Avg 0.447 2.758 9.717 1.770 6.071 0.914 0.294 1.789 6.578 2.712 10.002 0.441 1.762 25.933 0.292 2.713 1.864 0.922 1.650 2.535 0.224 1.567 4.481 Min 0.335 1.870 7.865 0.786 3.358 0.446 0.136 1.214 4.597 2.316 7.286 0.176 0.571 1.225 0.208 1.271 0.666 0.810 1.423 2.305 0.164 0.794 2.569

Max Load (lbs/year)

TN: 1501.3TP: 450.0

Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report Centreville, MD Data 3: Influent Sample Spreadsheet Centreville WW 24 hr Composite Influent Sampling 2023 Centreville WW 24 hr Composite Influent Sampling 2017 Sample Date BOD TSS Ammonia TKN Nitrate/Nitrite Sample Date BOD TSS Ammonia TKN Nitrate/Nitrite pH TP 3.20.23 148 76 28.2 36.4 0.24 19.19.17 71.53 57 26.3 26.41<0.065 7.06 1.5

3.22.23 115 121 27.5 36.7 1.91 29.20.17 79.8 57 26.5 29.13<0.042 7.12 1.73 3.24.23 135 137 21 16.2<0.10 310.03.17 184.8 358 39.8 46.46<0.065 7.57 7.97 3.27.23 129 124 21.1 34.4<0.10 410.04.17 101.1 70 28.4 32.88<0.042 7.34 3.63 3.29.23 122 189 26 41.3<0.10 510.10.17 132.2 60 36.2 31.85<0.042 7.19 3.57 3.31.23 109 50 37.4 38.2 1.01 610.11.17 199.3 120 30.3 38.46<0.042 7.27 5.57 710.17.17 96.7 75 32.1 29.45 0.304 7.26 2.4

810.18.17 106.5 62.5 36.9 30.27<0.065 7.22 2.13 910.24.17 180.4 73 35.9 37.12<0.065 7.2 3.53 Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

Appendix D

Major Process Equipment Catalog Information Page 101 Item 2: Dewatering Solids Item 3: Sequence Batch Reactor Item 4: Aerobic Granular Sludge Item 5: Final Clarifier 5/6/2024 1 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

May 6, 2024 Attn: Irene Pais Geiger Pump & Equipment Company 830 Tryens Road Aston PA 19014

USA

Phone: (610) 459-5747 Fax: (610) 459-3992 email: IPais@geigerinc.com Re: Centreville, MD - WRA - Centreville, MD Polychem™ Chain and Flight Sludge Collection System

BUDGETARY PROPOSAL

Brentwood Industries, Polychem Brand, proposes and offers to supply all materials and services as an Approved manufacturer and in general accordance with Brentwood's standard practices and specifications, clarifications, and information provided.

TECHNICAL SPECIFICATION(S): N/A

SECTION(S): N/A

ADDENDA RECEIVED: N/A

BRENTWOOD PROPOSES TO FURNISH POLYCHEM CHAIN AND FLIGHT EQUIPMENT AS FOLLOWS:

Four ( 4 ) Secondary Longitudinal Collector Mechanisms, Approximately 60 FT Long x 16.75 FT Wide x 14 FT AWD, 4 Shaft System Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 2 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

*ITEMS INCLUDED:

ITEM DESCRIPTION / MATERIAL

Drive Chain NH78, Reinforced Nylon Resin w/ 303 SS Pins Collector Chain Pins and Glass Reinforced Nylon Pins w/ Acetal Retainer Clips Retainer Clips Collector Chain Links NCS-720-S, Reinforced Thermoplastic Polyester Resin Flight Attachment Links NCS-720-S, Reinforced Thermoplastic Polyester Resin, F-22-8 3''x8'' nominal C-Channel w/ Integral Lip, Fiberglass Reinforced Plastic, Flights spaced at 10 Ft ( 3.05 m ) intervals

Wear Shoes Nylon 6-6 Hardware 316 SS Fillerblocks Polypropylene Headshaft Spindles Cast Nylon-6 Biaxially Wrapped Fiberglass Epoxy Tube(s) w/ Internal UHMW-PE Headshaft(s) Tubular Bearings Driven Sprocket(s) NH78, 40T, Cast Nylon-6, w/integral teeth Collector Sprockets for NCS-720-S, 23T, Cast Nylon-6 Headshaft(s) Set Collars Split, Cast Nylon-6, w/ 316 SS Clamping Band Headshaft Keys Glass Reinforced Nylon 6-6

Collector Sprockets for Stub NCS-720-S, 17T, Cast Nylon-6 Shafts Idler Stub Shafts Cast Nylon-6 w/UHMW-PE Outer Journal Bearing Retainer Plate for Stub Shafts Polycarbonate Wall Bracket Supports for Glass Reinforced Nylon 6-6 Return Track Run Shoe to Splice Wall Nylon 6-6 Bracket to Return Track Return Track 3'' x 3'' x 3/8'' Angle, Fiberglass Reinforced Plastic Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 3 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

*ITEMS INCLUDED (Continued):

ITEM DESCRIPTION / MATERIAL

Wear Strip UHMW-PE - 3/8'' thick x 2-5/8'' wide Chain Tightener(s) for Drive Nylon 6-6 7T Sprocket w/ Cast Nylon-6 Arm and FRP Adjustable Chain Mounting Bracket Limit Switch DPDT, Cutler Hammer, Zinc Die Cast, NEMA 4X, SS Arm Drive Sprocket Shear pin 11T Nylon Sprocket Mounted to 304 SS Shear Pin Hub Assembly Shear pin Kit(s) Aluminum Drive Unit Output Shaft 304 SS Drive(s) - Single, Each SEW Eurodrive Helical-Bevel Gear box (DIN-ISO) with integral mount

Driving (1) Collector SEW Motor (IEC), 1/2 HP, 3 PH, 60 Hz, 230/460 VAC Base Plate for Drive Unit(s) 304 SS Chain Guard for Drive Chain 304 SS Deflector Rail (if required by FRP Angle Rail w/UHMW-PE Wear Strip and Nylon

6-6 Wall Support

equipment layout) Brackets Anchor System 316 SS Adhesive for Anchors w/ Hilti Dispenser Above Item Descriptions/Materials may vary slightly after engineering * and consultant review.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 4 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

The following total estimated spare parts will be furnished for this project. After engineering, quantities may vary from quantities listed below. Spare Parts will be packaged separately and plainly identified.

SPARE PARTS INCLUDED

QTY DESCRIPTION

20 feet of drive chain 10% of all collector chain furnished 10% of all chain-to-flight attachment links furnished 12 shear pins for every drive sprocket assembly furnished 5 longitudinal flights complete with wear shoes, fillerblocks, and hardware 1 replacement 11T drive sprocket (sprocket plate only)

ITEMS SPECIFICALLY NOT INCLUDED

1 SmartGuard Flight and Sprocket Monitoring System 2 Rotating Scum Troughs or Helical Skimmers 3 Control Panel(s) 4 Effluent Troughs, Weirs, Baffles 5 Seismic Calculations 6 Hold Down Rail, 304 SS 7 Tank Measurements 8 PE Stamp of Submittals 9 Triple or Right Angle Drives Operating Two (2) Common Longs & Cross Collector Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 5 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

EXISTING CONCRETE STRUCTURE (IF APPLICABLE):

Pricing and schedule are based on limited structural information provided at the time of quotation and assume the necessary existing tank dimensions will be provided by purchaser in a timely manner to facilitate the start of submittals.

In lieu of customer supplied tank dimensions, purchaser may elect to procure Brentwood's Tank Measurement services.

Should the verified tank dimensions and equipment conditions differ from the information provided for quotation, and/or require special bracketry or supporting structures, Brentwood reserves the right to revise pricing and schedule accordingly. Delays associated with receipt of complete tank measurements, incomplete information from RFI’s, and release and approval to manufacture may result in changes to the price and schedule.

TANK MEASUREMENTS:

Tank Measurements are NOT included in this price or proposal, but can be provided and billed per attached published field labor and expense rates. If measurement services are purchased, Brentwood will require the assistance of one (1) person while on site to support tank measurements, and tanks must be completely drained and cleaned before entrance. In addition, customer / contractor shall supply all necessary equipment to safely access tanks (ladders,

lighting, etc.). Tank measurement services require a minimum 2 week notice and are based on technician availability.

SUBMITTALS:

Shop drawing and submittal preparation will be in accordance with Brentwood's standard submittal practices, and will be based on one submittal for all tanks at one time. Should separate submittals for each tank be required at separate intervals, Brentwood reserves the right to revise pricing accordingly.

TIME AND DELIVERY:

1. Brentwood will furnish initial submittal drawings approximately ten (10) Weeks

after receipt of executed purchase order and field verified structural dimensions and information. PE review, calculations and stamp (if required) may be sent at a later date under separate cover.

2. Estimated Submittal Review: Brentwood estimates a four (4) week review period by consultant or

customer.

3. We further propose to furnish the equipment approximately thirteen (13) weeks after receipt of final

engineering approval and returned submittal drawings and release to manufacturing.

FREIGHT:

Freight allowed, best way, point of manufacture to job site. Requests for specific methods of shipment will be at requestors’ expense. On-site transportation, unloading, and storage costs by others.

WEIGHT AND VOLUME:

Estimated weight is 11,300 Lbs. Estimated volume is One ( 1 ) Truck(s).

TAXES:

Pricing does not include any States’ sales tax if applicable, unless otherwise stated.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 6 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

SCHEDULE OF VALUES & PAYMENT TERMS:

1. 15% with Shop drawing and submittal transmission; 35% with approved submittals and/or release to

manufacture; 50% on material shipment. All payments 100% Net 30 days from invoice date. Payment terms subject to credit approval.

2. These terms are not contingent upon or in conjunction with any agreement purchaser has with

other parties.

3. For Brentwood Water & Wastewater Standard Terms and Conditions visit:

https://www.brentwoodindustries.com/terms/

ESCALATION:

The price(s) quoted are subject to adjustment to reflect increases in material cost(s), should these increases in price exceed 3% during the specified Schedule of Construction. Increases are based on price indexes for PVC (ChemData) and Stainless Steel (MEPS International), which can be provided upon request. It is understood and agreed that it will be Brentwood's option whether to invoke escalation, should the price exceed this amount.

BILL AND HOLD:

If Purchaser fails to take delivery on any scheduled delivery date based on the terms of the executed purchase Agreement, Brentwood reserves the right to reallocate any Product to other projects and reschedule production for the delayed Product. Purchaser will be required to accept any increase in price associated with the repurchase of material to fulfill the purchased Product requirements and the Product Delivery Date will be rescheduled in conjunction with

current production schedules.

If the Purchaser requests that Brentwood holds Product in excess of an agreed upon delivery date and Brentwood agrees to hold the Product, Purchaser will provide written notification to Brentwood to store the Product at its facilities for a period of time prior to shipment ("Bill and Hold"). Brentwood will provide written confirmation of the Bill and Hold to Purchaser, including a Statement of Transfer of Title and invoice.

Payment for the Bill and Hold material is due in accordance with the agreed upon terms in the executed purchase Agreement except to the extent dates must be adjusted due to delivery rescheduling, in which case adjusted dates will be shown on the invoice. All payments will be made in accordance with the invoiced payment terms and instructions.

For all Bill and Holds, Purchaser acknowledges that (i) they have made a fixed commitment to purchase the Product, (ii) risk of ownership for the Product passes to Purchaser upon signing Statement of Transfer, (iii) Purchaser has requested that the Product be on a Bill and Hold basis for legitimate business purposes, (iv) if no delivery date is determined at the time of invoicing and Statement of Transfer and Brentwood does not receive a request for delivery within two (2)months

from the Bill and Hold invoice date, Brentwood has the right to release the shipment upon written notice to Purchaser any time following the two (2) month period from Bill and Hold invoice date. Brentwood shall be entitled to storage charges of 1 ½% per month of the purchase value of stored material beginning 30 days after Bill and Hold invoice date and continuing until the Product is picked up by Purchaser or shipped by Brentwood. Upon receipt of request from

Purchaser to ship the stored Product, Brentwood shall use commercially reasonable efforts to ship the Product within two

(2) to 4 (four) business weeks following confirmed receipt of such request.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 7 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

VALIDITY:

This proposal is valid for a period not to exceed 90 days from latest date shown above unless extended by Brentwood in writing. Pricing on this project is based upon shipment schedule as shown above. Extensions to delivery timelines or requests for staged shipments may require renegotiation of pricing.

FIELD SERVICE STARTUP AND TRAINING:

The services of a qualified Brentwood field technician is included to assist in inspection of installed equipment, startup and field testing, certification, and operator training, if required by specification. Duration limited to Two (2) trip(s) for Four (4) man-day(s) on site total. Non use of contractual field service days does not generate a credit on this project.

Field service requires a minimum 2 week notice and is based on technician availability. Less notice may be accommodated with additional costs.

OPERATION AND MAINTENANCE MANUALS:

Unless otherwise specified, one (1) digital copy of our O&M manual and installation and layout drawings will be furnished on or before shipment of equipment. Digital copy can be downloaded from our FTP site or finished on a USB Flash drive. Digital copy of O&M shall be in Adobe pdf format and be locked and uneditable.

WARRANTY:

Brentwood warrants material supplied on this project to be free from defects in workmanship or materials for a period of twelve (12) months from date of certification by an authorized Brentwood representative or eighteen (18) months from date of shipment, whichever shall occur first. Warranty excludes labor to install or remove parts. Chain and flight system is designed for continuous operation, and intermittent operation is not recommended due to potential for excess sludge

build up. Damage resulting from intermittent operation of chain and flight equipment is not covered under this warranty.

PAINTING AND COATINGS:

Stainless Steel and plastic equipment shall not be painted. Unless otherwise specified, all ferrous wetted components will be provided with a surface preparation of SSPC-SP10 Near White Metal and a shop primer 1 coat of Sherwin Williams Dura-Plate 235 Multi-Purpose Epoxy @ 4 Mils D.F.T. It is the responsibility of the contractor to ensure finish paint is compatible with specified primer. Any adhesion issues between coats are not the responsibility of Brentwood. The top

coat must be applied within 6 months of the prime coat, otherwise the assembly surface will need to be abraded or the primer will need to be removed and surface preparation redone prior to application of the top coat, by others. OEM components above deck (drive units, bearings, actuators, etc.) shall be furnished with manufacturer's factory finish.

AMERICAN IRON AND STEEL ACT:

Per Implementation of American Iron and Steel provisions of P.L. 113-76, Consolidated Appropriations Act, 2014, Brentwood’s Polychem brand clarifier System and accessories is considered a mechanical system and is not considered construction material or structural steel subject to AIS requirements.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 8 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

GENERAL EXCLUSIONS*:

1. Contractor/customer shall be responsible for field verification of all dimensions.

2. Foundations, supports for Polychem equipment (diaphragm plates) or special mounting plates.

3. Bid, performance, supply, or maintenance bonds.

4. Installation of equipment and anchor systems, concrete, sealing compounds, shim stock or grout.

5. Grouting behind idler stub shafts, head shaft spindles, & return track wall brackets is not included, but is

required for these systems.

6. Tools or spare parts (unless listed elsewhere in this Proposal).

7. All reducer oil, bearing grease, or other lubricants.

8. Field paint, touch-up, finish painting, or finish coatings.

9. Unloading, hauling, erection, and storage of equipment.

10. Grease line piping (unless listed elsewhere in this Proposal) or grease guns.

11. Any electrical components or controls not shown in items included section of this Proposal.

12. All control panels (unless listed elsewhere within this Proposal), unistrut supports / mounting for control

panels, electrical conduit, wires, or wiring, wire fittings, or boxes.

13. Wall Sleeves for scum troughs, weirs, baffles, overflow weirs, effluent troughs.

14. Anchor pull out testing.

15. PI&D drawings

16. Conduit sizing or drawings.

17. Detailed specific storage plans or maintenance schedules for installed equipment outside of

Brentwood's standard maintenance and preventative maintenance information.

18. Factory assembly of components.

19. Any component shown or described on a drawing and not included in the Items Included section of

this Proposal, or any component or service not shown in this Proposal.

*unless above items are listed as included elsewhere in this Proposal, they are excluded.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 9 of 13

BUDGETARY PROPOSAL #WG08049 CENTREVILLE, MD - WRA - CENTREVILLE, MD

PRICING SUMMARY:

LUMP SUM BUDGETARY BASE PRICE: $311,700.00

ADDERS TO BASE OFFERING:

Four ( 4 ) 304 SS Rotating Scum Troughs, Manual Lever Operated, Approximately 12-Inch Diameter x 16.75FT Long: $183,050.00 Proposal Submitted By:

Jonah Graciani Jonah Graciani, Sales Estimator Brentwood Industries, Polychem Brand email: jonah.graciani@brentwoodindustries.com Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 10 of 13 Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 11 of 13 Brentwood Water Group (Water & Wastewater) Standard Terms and Conditions of Sale Applicability and Acceptance These terms and conditions of sale (“Terms) are the only terms which govern the sale of product (“Product”) by Brentwood Industries, Inc. (“Brentwood”) to Purchaser (“Purchaser”). Brentwood and

Purchaser together are the “Parties” and each a “Party” herein. Brentwood’s accompanying quotation or proposal (collectively “Proposal”) and these Terms (collectively this “Agreement”), comprise the entire agreement between the Parties and supersede all understandings, agreements, negotiations, representations, or communications. In the event of a conflict between these Terms and a Proposal, the terms and conditions in the Proposal prevail. Brentwood’s commencement of work or service does not constitute acceptance of any Purchase Order. No Purchase Orders will be binding upon Brentwood

without express written acceptance by an authorized Brentwood employee. These Terms will be the sole, controlling terms for Purchaser’s Purchase Order (“Purchase Order”) and no other terms and conditions will apply.

Pricing and Payment:

Payment to be 100% prepayment of goods before shipment unless a credit application has been completed and an extension of credithas been approved. Approved payment terms shall be due in full within thirty (30) days from invoice date. Pricing is in accordance with Brentwood’s Proposal. Brentwood reserves the right to adjust the Proposal price at any future time due to raw material and/or labor cost fluctuations greater than +/-3%.

Shipment and Title:

The shipment terms unless stated otherwise in Brentwood’s Proposal will be EXWORKS. Risk of loss and title transfer at Brentwood’s facility. Brentwood may, without liability or penalty, make partial shipments of Products to Purchaser.

Inspection and Claims:

Upon delivery of Product, Purchaser must inspect the Product for freight damage and must notify Brentwood in writing within five(5) days after delivery. Furthermore, Purchaser agrees to inspect and accept the Product within a reasonable timeframe. Brentwood may waive claims not made in accordance with the above terms in thissection.

Default:

Purchaser's failure to make payment as agreed and according to invoices or Purchaser’s failure to perform any of its other obligations under this Agreement constitutes a default. In the event of default, Brentwood will provide written Notice of the default (in accordance with the Notices section of this Agreement) to Purchaser.IfPurchaser does not i) correct the default or ii) address how it plans to correct

the default in writing to Brentwood within five (5) business days from receipt of Notice of default, Purchaser will remain indefault and Brentwood may do any of the following, (i) exercise any and all other rights and remedies of a secured Party under Article 9 of the UCC or applicable law ; (ii) suspend any further Product deliveries or provision of services until Purchaser pays its obligations in full; iii) be

excused from any of its performance obligations under this Agreement resulting from Purchaser’s delays or inability to complete its obligations; iv) send Purchaser’s past due invoice(s) to collections for nonpayment of obligations and report Purchaser’s non-payment to appropriate credit agency.

Delays::

Delays in project schedule beyond the expected ship date not caused by Brentwood which result in additional costs not included in quoted price may be invoiced by Brentwood to Purchaser.

Storage Fees:

Unless otherwise agreed upon by Brentwood and Purchaser, in the event Purchaser notifies Brentwood it cannot take delivery onthe agreed upon delivery date on the face of Purchaser’s Purchase Order, Brentwood will store the Product free of charge for up to thirty (30) days after the initially agreed delivery date. After the thirtieth (30th) day, Purchaser agrees to pay a monthly storage fee equal to one and

one-half (1.5%) percent of the invoice price of the Product. The monthly storage fee will be due in full upon receipt of invoicefor the storage fee regardless of whether Purchaser has been invoiced or has paid for the Product.

Termination:

Brentwood or Purchaser may terminate this Agreement if either Party defaults by materially breaching its obligations in this Agreement, provided the breaching Party does not commence correction of the breach within five (5) business days from receipt of written notice of default. The Parties will agree upon a reasonable amount of time to correct the breach. In the event the Party in default fails to correct

the breach within the agreed upon time frame, the other Party may terminate the Agreement by providing written notification to the Party in default. In the event of termination, the Purchaser agrees to pay Brentwood cancellation charges in accordance with the table below based on the Purchase Order Value.

C ontracted Ship m ent (w eeks) U p to 8 8.01 - 12 12.01 - 16 16.01 - 20 20.01 - 24 24.01 - 28 28.01 - 32 32.01 - 36 36.01 - 40 40.01 - 44 44.01 - 48 48.01 - 52 52.01 - 56 E lap sed T 0 - 2 2 0 1 5 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 im e – from date of E xecuted P 2.01 - 4 4.01 - 6 5 0 7 5 4 0 6 0 2 5 4 5 1 5 2 5 1 0 2 0 1 0 1 5 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 urchase O

6.01 - 8 1 0 0 8 0 6 0 4 5 2 5 2 0 1 5 1 5 1 0 1 0 1 0 1 0 1 0 rder to date of C 8.01 - 12 1 0 0 8 5 6 5 5 0 2 5 2 0 2 0 1 5 1 5 1 5 1 5 1 5 ancellation (w 12.01 - 16 1 0 0 8 5 7 0 5 0 3 5 2 5 2 5 2 5 2 5 2 0 2 0 eeks) 16.01 - 20 1 0 0 9 0 7 0 6 0 5 0 5 0 4 5 4 5 4 0 3 5 20.01 - 24 1 0 0 9 0 7 5 6 0 6 0 5 5 5 5 5 0 5 0 24.01 - 28 1 0 0 9 0 8 5 7 0 6 5 6 0 5 5 5 5 28.01 - 32 1 0 0 9 5 8 5 8 0 6 5 6 0

6 0 32.01 - 36 1 0 0 9 5 9 0 8 0 7 0 7 0 36.01 - 40 1 0 0 9 5 9 0 8 5 8 0 40.01 - 44 1 0 0 9 5 9 0 8 5 44.01 - 48 1 0 0 9 5 9 0 48.01 - 52 1 0 0 9 5 52.01 - 56 1 0 0 Changes:

Purchase Order changes are subject to Brentwood’s written approval, and additional time and charges may apply. Brentwood willnot be liable for any delays due to change order requests. Brentwood may make changes to its Product without obligation, apply or manufacture such changes in any Product manufactured prior thereto.Brentwood may make such changes to any ordered Product as does not, in Brentwood’s reasonable judgment, interfere with the satisfactory operation of the Product.

Taxes:

All government charges upon the production, shipment or sale of the Product, including, without limitation, sales, use, occupation, export and import taxes, and any other impositions by any government whatsoever, direct or indirect, including those required to be collected by Brentwood, will be paid by Purchaser or, in lieu thereof, Purchaser will furnish Brentwood with an exemption certificate acceptable to the taxing authority. Brentwood reserves and Purchaser disclaims all rights to drawback of duties paidon materials used in the manufacture of the Product. Purchaser will

supply Brentwood with proof of exportation and all other documents necessary and otherwise cooperate to obtain payment thereof.

Returns:

No Product may be returned for credit or otherwise unless Purchaser receives Brentwood’s authorization. Product authorized for return or credit must be returned in good condition, in its original packaging with completed identification and with all supporting documentation detailing of any claimed defect as required by Brentwood. All shipping and freight charges shall be prepaid by the Purchaser. The returned Product may be subject to a restocking charge of 30%.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 12 of 13 Warranty:

Brentwood warrants against defects in materials and workmanship. Warranty coverage is contingent on proper storage, installation, use, operation, maintenance, and shutdown procedures, all occurring under ordinary conditions and in compliance with good industry standards, the approved design criteria, Brentwood’sapproved Submittal and Operation and Maintenance Manual. The Warranty period shall be limited to twelve (12) months from Product shipment. The terms of this Warranty shall be modified only through written agreement by an authorized Brentwood employee.

The remedy for a covered defect during the Warranty period shall be limited, at Brentwood’s option and control, to repair or replacement of defective Parts and Components, including shipping costs.The remedy excludes costs of labor, removal of non‐conforming Products, and expenses related to installation of the replacement Products.

THE TERMS OF THIS WARRANTY ARE THE SOLE AND EXCLUSIVE OBLIGATION OF BRENTWOOD TO PURCHASER OR THIRD PARTY FOR CLAIMS RELATED TO THE PRODUCT.UNDER NO CIRCUMSTANCE SHALL BRENTWOOD BE LIABLE TO ANY PERSON OR ENTITY FOR ANY INCIDENTIAL, CONSEQUENTIAL, SPECIAL, OR INDIRECT DAMAGES OR ANY OTHER LOSS, COST, OR EXPENSE OTHER THAN SPECIFICALLY STATED IN THIS WARRANTY.OTHER THAN THE EXPRESS LIMITED WARRANTIES MADE HEREIN, BRENTWOOD EXPRESSLY DISCLAIMS ANY AND ALL OTHERWARRANTIES, EXPRESS OR IMPLIED BY LAW,

WITH RESPECT TO ANY SERVICE OR DELIVERABLE, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESSFOR A PARTICULAR PURPOSE, AS WELL AS ANY WARRANTIES WHICH MAY ARISE FROM PRIOR COURSE OF DEALING, CUSTOM, TRADE USAGE, PROVISION OF SAMPLES, PRODUCT LITERATURE OR WEBSITE CONTENT.

Limitation of Liability:

REGARDLESS OF THE FORM OF ACTION, BRENTWOOD’S LIABILITY RELATING TO THE PRODUCT OR THE MANUFACTURE, SHIPPING, SALE OR USE OF THEPRODUCT SHALL NOT EXCEED THE PRICE PAID BY PURCHASER FOR THE SPECIFIC PRODUCT GIVING RISE TO THE CAUSE OF ACTION. BRENTWOOD, ITS AFFILIATES, AND THEIR OFFICERS, DIRECTORS,EMPLOYEES AND AGENTS SHALL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, EXEMPLARY, PUNITIVE OR CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, LOSS OF PROFITS, LOSS OF USE, DOWNTIME, FAILURE TO DETECT ANY FLAW

IN ANY SUBJECT MATTER OF ANY TEST, LOSS OF GOODWILL, BUSINESS INTERRUPTION, DELAY IN PERFORMANCE, OR LOST OPPORTUNITIES. REGARDLESS OF THE FORM OF ACTION, WHETHER IN CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT PRODUCT LIABILITY OR OTHERWISE IN CONNECTION WITH THE SUPPLY OR SUBSEQUENT USE OR POSSIBILITY OF SUCH DAMAGES.

Indemnification:

Purchaser will at all times indemnify, defend and hold harmless Brentwood, its officers, directors, employees, agents, servants and representatives from and against any and all damages, liabilities, losses, claims, suits, penalties, fines, costs, and expenses, including attorneys’ fees (collectively, “Claims”) arising directly or indirectly out of or in connection with any (a) infringement or misappropriation of any

patent, trademark, or other intellectual property right, including third Party rights, arising from Brentwood’s adherence toPurchaser’s Specifications; (b) use, operation or possession of Brentwood Product, except to the extent the Claim arises from the gross negligence or willful misconduct of Brentwood; or (c) breach byPurchaser of any provision of any Agreement with or obligation to Brentwood.

Brentwood will at all times indemnify, defend and hold harmless Purchaser from and against loss, injury, damage and liabilityarising directly in connection with bodily injury death, or destruction of tangible or real property, including loss of use directly resulting from or caused by Brentwood or Brentwood’s product, its negligent act, error, omission or for damages arising from Brentwood’s gross

negligence or willful misconduct in performance of its obligations under this Agreement. Claims and damages are limited to Brentwood’s proportionate percentage of negligence and/or fault.

Insurance:

Brentwood will maintain and carry insurance including, but not limited to Commercial General Liability in a sum of $1,000,000per occurrence and Workers Compensation in amounts as required by applicable statute. Additional coverages may be available. Upon request, Brentwood will provide to Purchaser a certificate ofinsurance evidencing its coverages.

Confidential Information:

All non-public, confidential and proprietary information (“Confidential Information”), whether disclosed orally or reduced to writing, whether or not marked or otherwise designated or not identified as such. Confidential Information does not include information which: (i) is or becomes available to the public generally (otherthan as a result of a disclosure by the Purchaser in violation of this Agreement);

(ii) is subject to public disclosure under any federal, state or local law, ordinance or regulation; (iii) becomes available to Purchaser on a non-confidential basis from a source other than Brentwood; or (iv) was known by or was available to Purchaser prior to or at the time Brentwood disclosed it.

Purchaser agrees to protect and safeguard all Confidential Information with at least the same degree of care as the Purchaserwould protect its own Confidential Information, but in no event with less than a commercially reasonable degree of care. Purchaser shall hold all Confidential Information in confidence and shall disclose it only to its employees needing to use the Confidential Information for the

limited purposes of this Agreement and said employees shall be bound to the confidentiality Terms of this Agreement. No other disclosure of Confidential Information is allowed unless written permission is granted by Brentwood. Purchaser agrees not to use Brentwood’s Confidential Information for any purpose other than this Agreement. Purchaser agrees not to use the Confidential Information in any manner to Brentwood’s detriment, including without limitation, to reverse engineer, disassemble, analyze, decompile, copy, modify, develop, or design.

Force Majeure:

Brentwood shall not be liable or responsible to Purchaser, nor be deemed to have defaulted under or breached this Agreement, forany failure or delay in fulfilling or performing any term of this Agreement to the extent Brentwood’s failure or delay is caused by or results from a forcemajeureevent, including, acts of God;flood, fire, earthquake, pandemics, disease outbreaks, explosions or other natural disasters; war, invasion, hostilities, terrorist acts, civil unrest; government orders or actions; embargoes or blockades in effect on or after the date of this Agreement; national emergency; strikes,

labor stoppages or slowdowns, or other industrial disturbances; shortage of adequate raw materials, labor, power, or transportation facilities; and other similar events beyond the reasonable control of Brentwood.

Brentwood shall give notice within fourteen (14) days of the force majeure event or as soon as reasonably practicable to Brentwood, stating the period of time the occurrence is expected to continue.

Brentwood shall use diligent efforts to end the failure or delay and ensure the effects of such are minimized. Brentwood shall resume the performance of its obligations as soon as reasonably practicable after the removal of the cause. In the event Brentwood remains unable to perform its obligations within ten (10) weeks from notice of force majeure event Purchaser may terminate the Agreement.

Governing Law and Jurisdiction:

This Agreement shall be construed under the laws of the Commonwealth of Pennsylvania without reference to conflicts of law principles. The Parties hereby agree that disputes hereunder shall be subject to the exclusive jurisdiction and venue of the courts of Berks County, Pennsylvania, in either the Pennsylvania Court of Common Pleas or the United States District Court for the Eastern District of Pennsylvania. The Purchaser waives any objections based on personal or subject matter jurisdiction or venue.

Export Control:

Purchaser will not use, distribute, transfer, or transmit any Product, components or technical information (even if incorporatedinto other products) provided in connection with this transaction except in compliance with U.S. export laws and regulations (the “Export Laws”). Purchaser will not, directly or indirectly export or re-export the following items to any country which is in the then-current list of

prohibited countries specified in any applicable Export Laws: (a) the Product, components or technical data disclosed or provided to Purchaser by Brentwood; or (b) any improvements or variations of such Product, components or technical data. Purchaser agrees to promptly inform Brentwood in writing of any written authorization issued by the U.S. Department of Commerce office of export licensing to export or re-export any such items referenced in (a) or (b). The obligations stated above in this clause will survive the expiration, cancellation or termination of this Agreement.

Translation:

This document may be translated into one or more languages; however, the English translation shall be the official version and shall prevail over other translations. All dollar amounts are United States currency unless specified otherwise. Purchaser shall abide by the United States Foreign Corrupt Practices Act of 1997, as amended.

Assignment:

Purchaser shall not assign or delegate its obligation hereunder without Brentwood’s written consent, and any attempted assignment or delegation without such written consent shall be void.

Waiver:

No waiver by Brentwood of any of the provisions of this Agreement is effective unless explicitly set forth in writing and signedby Brentwood. No failure to exercise, or delay in exercising, any right, remedy, power or privilege arising from this Agreement operates, or may be construed, as a waiver thereof. No single or partial exercise of any right, remedy, power or privilege hereunder precludes any

other or further exercise thereof or the exercise of any other right, remedy, power or privilege.

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 5/6/2024 13 of 13 Severability:

If any term or provision of this Agreement is invalid, illegal or unenforceable in any jurisdiction, such invalidity, illegalityor unenforceability shall not affect any other term or provision of this Agreement or invalidate or render unenforceable such term or provision in any other jurisdiction.

Notices:

All notices, requests, consents, claims, demands, waivers and other communications hereunder (each, a “Notice”) shall be in writing and addressed to the Parties at the addresses set forth on the face of the Proposal or to such other address that may be designated by the receiving Party in writing. All Notices shall be delivered by personal delivery, nationally recognized overnight courier (with all fees prepaid or certified or registered mail (in each case, read receipt requested, postage prepaid). Except as otherwise provided inthis Agreement, a Notice is effective only (a) upon receipt of the receiving Party,

and (b) if the Party giving the Notice has complied with the requirements of this Section.

Authority:

The individual assenting to or executing any documents or orders, whether as a hard copy or, on behalf of Purchaser acknowledges, represents and warrants that he or she has read and understands these Terms and Conditions and has been duly authorized by the Purchaser to execute such on behalf of the Purchaser and bind the Purchaser to these Terms and Conditions.

Relationship of the Parties:

The relationship between the Parties is that of independent contractors. Nothing contained in this Agreement shall be construed as creating any agency, partnership, joint venture or other form of joint enterprise, employment or fiduciary relationship between the Parties, and neither Party shall have authority to contract for or bind the other Party in any manner whatsoever.

Survival:

Provisions of this Agreement which by their nature should apply beyond their terms will remain in force after any terminationorexpiration of this Agreement.

Amendment and Modification:

This Agreement may only be amended or modified in writing by Brentwood and executed by an authorized representative of each Party.

By signing below both Parties accept Brentwood Water Group (Water and Wastewater) Standard Terms and Conditions of Sale.

BRENTWOOD INDUSTRIES, INC. PURCHASER

By: ____________________ By:

Print Name: ____________________ Print Name:

Title: Title:

Brentwood Industries, Inc. Company: ______________________

Brentwood Industries, Inc.

500 Spring Ridge Dr., Reading PA 19610 Phone: 610.374.5109 brentwoodindustries.com Fax: 610.685.0137 1 Item 6: Membrane Bioreactor Budget Proposal for the Centreville, MD MBR ZeeWeed Membrane Bioreactor System Submitted to:

Sherwood-Logan & Associates Andrew Kreider (603) 848-3950 akreider@sherwoodlogan.com June 29th, 2023 Veolia Proposal Number: 556484 Submitted by:

Graham Best- Regional Manager Tel: (905) 465-3030 Ext. 3209 Email : graham.best@veolia.com Veolia Confidential and Proprietary Information Proposal #: 557243 Page 1 of 15 Table of Contents 1 Introduction to ZeeWeed Membrane Bioreactor (MBR) Technology ......................................................................................................... 3 Benefits of Veolia System Design .....................................................................................5

1.1.1 Pre-Engineered Z-MOD L Process Pump Skid .....................................................5 1.1.2 Membrane Aeration System Design ......................................................................5 1.1.3 Membrane Cleaning Systems ...............................................................................6 2 Design ................................................................................................................. 7

2.1 Influent Flow Data .............................................................................................................7 2.2 Influent Quality ..................................................................................................................7 2.3 Effluent Quality ..................................................................................................................7

2.4 Influent Variability ..............................................................................................................8 2.5 Biological System Design ..................................................................................................8 2.6 Membrane System Design ................................................................................................9 3 Scope of Supply ............................................................................................... 10

3.1 Scope of Supply by Veolia ..............................................................................................10 3.2 Scope of Supply by Others .............................................................................................12 4 Commercial ....................................................................................................... 15 4.1 System Pricing ..............................................................................................................15

4.2 Freight Terms.................................................................................................................15 4.3 Equipment Shipment and Delivery ..............................................................................15 4.4 Terms and Conditions of Sale ......................................................................................15 Veolia Water Technologies & Solutions

Confidential and Proprietary Information The enclosed materials are considered proprietary property of Veolia Water Technologies & Solutions (Veolia). No assignments either implied or expressed, of intellectual property rights, data, know-how, trade secrets or licenses of use thereof are given. All information is provided exclusively to the addressee and agents of the addressee for the purposes of evaluation and is

not to be reproduced or divulged to other parties, nor used for manufacture or other means, without the express written consent of Veolia. The acceptance of this document will be construed as an acceptance of the foregoing.

*The following are trademarks of Veolia Water Technologies & Solutions and may be registered in one or more countries: InSight, LEAPmbr, Z-MOD, ZeeWeed, and ZENON Veolia Confidential and Proprietary Information Proposal #: 557243 Page 2 of 15 1 Introduction to ZeeWeed Membrane Bioreactor (MBR) Technology The proposed ZeeWeed Membrane filtration system for the Centreville, MD MBR is designed to ensure reliable long-term performance and to maximize operational flexibility.

At the core of the MBR process is the ZeeWeed 500 series hollow fiber membrane. The ZeeWeed 500 series membrane is a reinforced hollow fiber ultrafiltration membrane that was designed specifically for high solids applications. The membrane fiber has a nominal pore size of 0.04 m, a tensile strength of 135 lbs, (vs 3 lbs for non-reinforced fibers) and is highly resistant to chemicals, including acids, bases and chlorine, allowing for

flexible cleaning regimes. The membrane material is both mechanically and chemically bonded to the porous supporting braid that provides the mechanical strength. This doublebonding means that the membrane will never separate from the braid. The relatively thin layer of membrane layer is the key to ensuring long-term permeability. Some membranes attempt to make up for their lack of a reinforced braid with a thicker membrane wall. The increase in

strength is only marginal compared to a thinner non-reinforced fiber, and is still orders of magnitude less than a reinforced fiber. The cost of this approach comes from the tendency to trap organics and colloidal material inside the membrane material, rendering them permanently fouled.

The membrane is manufactured and assembled into discrete units called “modules” or small membrane subunits. These are the basic building blocks of the membrane system that are manifolded together to create a “cassette” or large membrane subunit. The cassette, proposed for the Centreville, MD MBR, is 52M ZeeWeed 500D cassette and each module in the cassette has 430 ft2 of membrane area.

In the ZeeWeed membrane filtration process, the membrane cassettes are immersed directly in the mixed liquor. A series of cassettes connected to a common permeate header is called a “membrane train”. Each membrane train is connected to the suction side of a duty pump for permeation. The pump creates a slight vacuum in the permeate header to draw treated water from the outside in through the hollow fiber

ZeeWeed 500 Cassette membranes, leaving the mixed liquor solids on the outside of the membrane.

Permeate is then directed to downstream ZeeWeed Membrane Trains disinfection or discharge facilities. Air, in the form of and Cassette large bubbles, is introduced below the bottom of the membrane modules, producing turbulence that scours the outer surface of the hollow fibers to keep them clean.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 3 of 15 The proposed system design utilizes LEAPmbr Aeration, SUEZ’s latest aeration technology for MBR systems. A specially designed and highly efficient aeration system is used to scour the outside surface of the membranes and move feed water solids away from the membrane fibers. LEAPmbr Aeration Technology uses factory installed aerators which are integrated into the base of each

ZeeWeed 500 cassette.

LEAPmbr aerators use no moving parts within the membrane aeration system. A single air pipe and a single permeate pipe (per membrane train) provide the connection between the immersed membranes and the permeate pumps and blowers that comprise the rest of the ZeeWeed system. LEAPmbr aeration greatly simplifies the aeration system and reduces air requirements for the system.

LEAPmbr Aeration – Simple Energy Efficient Aeration LEAPmbr aeration provides the most intense air scour, which is ideal for removing solids from a membrane bundle. This is ONLY possibly because of the increased strength that comes from the reinforcing braid. A single monofilament fiber with no supporting braid is cheaper to manufacture, but it cannot survive the mechanical stress of a large-bubble, high-shear air scour device. Similarly,

flat plate and similar modified plates will not allow for the free movement of fibers Veolia Confidential and Proprietary Information Proposal #: 557243 Page 4 of 15 and the passage of large bubbles, which results in a tendency to sludge in unrecoverable fashion.

The combination of a robust, high-strength fiber and large-bubble air scour are the keys to long-term performance stability.

Benefits of Veolia System Design At Veolia, our goal is to create long term partnerships with our customers, which is why we design our systems with you in mind. Our approach to the proposed ZeeWeed membrane bioreactor system has been optimized around the following three key system attributes.

 robust design – proven design parameters with scope and configuration options for a wide variety of conditions  simple operations – simple & automated operations coupled with Veolia support for the operating team  lowest cost of ownership for the Owner We are continuously striving to improve our system designs to provide optimal solutions for our customers. Highlighted below are several systems that we have optimized to meet

your needs.

1.1.1 Pre-Engineered Z-MOD L Process Pump Skid The Z-MOD L process pump skid is a pre-engineered equipment skid that helps simplify ZeeWeed membrane filtration system design and installation. The Z-MOD L skid is a “plug and go” skid that incorporates most of dedicated membrane train equipment onto a single prefabricated equipment skid for simple onsite installation.

The Z-MOD L skid is designed to handle all membrane train flow conditions and includes a bi-directional process pump that performs both permeation and backpulse duty. A traindedicated remote I/O panel is installed on the Z-MOD L skid, with all skidded equipment and instrumentation pre-wired and tested within the panel.

1.1.2 Membrane Aeration System Design Aeration is one of the most important operating parameters for successful long term MBR operations and is a significant component of operating cost.

Veolia MBR system utilizes a very simple aeration strategy which minimizes the amount of instrumentation and controls required to achieve energy efficient membrane aeration.

No complex control loops or complicated airflow measurement devices are required for LEAPmbr aeration technology to achieve energy efficiency.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 5 of 15 1.1.3 Membrane Cleaning Systems Veolia has developed membrane design principles based on best engineering practices that ensure the permeability of the membrane is maintained over the life of the membranes.

A fully automated suite of membrane maintenance procedures will ensure long-term, successful operation, including:

 in-situ chemical membrane cleaning performed directly in the membrane process tanks so your operators don’t waste time moving cassettes.

 the ability to increase or decrease the frequency of chemical cleans to fit the operating conditions.

 the ability to backpulse, when needed, to greatly improve your operator’s ability to recover from non-design conditions.

The above cleaning systems can be automated, resulting in operators having available a full suite of comprehensive cleaning systems which are simple to use and initiate.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 6 of 15 2 Design The proposed ZeeWeed membrane filtration system for the Centreville, MD MBR is offered based on using the design parameters summarized in the following sections.

2.1 Influent Flow Data The influent design flows are summarized in the table below.

Flow Conditions1 Capacity Units Average day flow (ADF) 0.75 MGD Max month flow (MMF)1 0.93 MGD Max Day flow (MDF)1 2.25 MGD Peak hour flow (PHF) 2.5 MGD Maximum flow with one train offline for

2.25 MGD

maintenance or cleaning (less than 24 hours) Note 1: Any flow conditions that exceed the above-noted flow limits should be equalized prior to treatment in the ZeeWeed membrane filtration system.

Note 2: The flow definitions as seen in the table above are as follows:

• ADF – the average flow rate occurring over a 24-hour period based on annual flow rate data.

• MMF – the maximum monthly flow rate sustained less than one month period based on annual flow rate

data.

• MDF – the maximum daily flow rate sustained over a 24-hour period based on annual flow rate data.

• PHF – the maximum flow rate sustained over a 2-hour period based on annual flow rate data.

2.2 Influent Quality The design solution proposed is based on the wastewater characteristics detailed below.

The concentrations listed below are specific to the flow used for the biological design as listed in Section 2.1 below.

Influent Design Parameters Value Unit design influent temperature 10 ºC BOD 175 mg/L 5 TSS 200 mg/L inert solids fraction1 20 % NH3-N 281 mg/L TKN 40 mg/L TP 8 mg/L Alkalinity1,2 250 mg/L as CaCO 3 Note 1: Parameter value assumed.

Note 2: Veolia is assuming that sufficient influent alkalinity is available for the proper performance of the biological system. Should influent alkalinity not be sufficient, chemical addition by the buyer will be required.

2.3 Effluent Quality The following performance parameters are expected upon equipment startup and once the biological system has stabilized based on the data listed in Sections 1.1 and 1.2.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 7 of 15 Effluent Design Parameters Value Unit BOD ≤ 5 mg/L 5 TSS ≤ 5 mg/L NH -N ≤ 1 mg/L 3 TN1 ≤ 3 mg/L TP ≤ 0.3 mg/L turbidity ≤ 1 NTU Note 1: TN ≤ 3 mg/L corresponds to a minimum design temperature of 10ºC and < 0.1 mg/L recalcitrant dissolved organic nitrogen in the influent.

2.4 Influent Variability Influent wastewater flows or loads in excess of the design criteria defined above should be equalized prior to entering the membrane tanks. In the event that the influent exceeds the specifications used in engineering this proposal, or the source of influent changes, the ability of the treatment system to produce the designed treated water quality and/or quantity may be impaired. Buyer may choose to continue to operate the system but

assumes the risk of damage to the system and/or additional costs due to increased membrane cleaning frequency, potential for biological upset and/or increased consumables usage.

2.5 Biological System Design For the Centreville, MD MBR project, the screened influent wastewater first enters the pre-anoxic tank for denitrification and alkalinity recovery. Mixed liquor will then be transferred to aerobic tanks, where BOD is oxidized and most of NH3-N is converted into NO3-N. The post-anoxic tank is set up with organic carbon dosing for further denitrification. Finally, the mixed liquor enters the membrane tanks where biomass is

separated from the mixed liquor by the ZeeWeed 500 membranes. The coagulant will be dosed to the MBR system for further TP removal to meet the TP effluent target. The flow sheet is shown below.

A permeate pump draws permeate through the membrane which is then pumped through a disinfection system by others.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 8 of 15 Waste sludge is diverted from the RAS line to the sludge holding tank (by others). The frequency of wasting is a function of influent characteristics, reactor design and operator preferences.

The following table is a summary of the biological design.

Biological Design Parameters Value Unit flow basis for biological design 0.93 mgd total pre-anoxic tank working volume 70,000 gal total aerobic working volume 280,000 gal Total post-anoxic tank working volume 110,000 gal total bioreactor working volume (excluding membranes) 460,000 gal total design HRT (including bioreactors and membrane 11.9 hours tanks) aerobic design SRT (excluding membrane tanks) 13 days

waste sludge removal (based on MMF and 10 g/L) 18,000 gpd design MLSS concentration in bioreactor ≤ 8,000 mg/L Alum addition 150 gpd Methanol Addition 1 40 gpd design liquid depth in bioreactor 18 ft Note 1: Alternate carbon sources can be utilized such as Micro-C.

2.6 Membrane System Design Membrane Design Parameters Design Number of membrane trains 3 Number of ZMODL skids 3 Number of cassette spaces per train 3 Number of cassettes installed per train 3 ZeeWeed 500D, 430 Type of cassette (modules per cassette) ft2, 52M Module design per train (1x52) + (2x40) Total number of modules installed per train 132 Total number of modules installed per plant 396 Total number of cassettes installed per plant 9

Spare space 33.3% Membrane tank internal dimensions (one train) 21.7’ × 9’ × 13’ L x W x H (ft) Note 1: Tank dimensions and volumes are preliminary only and may change slightly once final detail design commences.

Note 2: The ultrafiltration system is designed for installation within concrete tanks supplied by buyer.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 9 of 15 3 Scope of Supply 3.1 Scope of Supply by Veolia The following table provides a summary of the main equipment included with the supply of the ZeeWeed MBR System.

Quantity Description (1) Membrane Blower & Associated Equipment 3+1 Inlet filters and silencers 3+1 PD membrane blowers 3+1 Sound enclosures 3+1 Discharge silencers 3+1 Discharge pressure relief valves 3+1 Discharge pressure indicators c/w isolation valves 3+1 Discharge check valves 3+1 Discharge flexible connectors with clamps 3+1 Blower discharge low flow switches 3+1 Membrane blower isolation valves

Process Blower & Associated Equipment 2+1 Inlet filters and silencers 2+1 PD membrane blowers 2+1 Sound enclosures 2+1 Discharge silencers 2+1 Discharge pressure relief valves 2+1 Discharge pressure indicators c/w isolation valves 2+1 Discharge check valves 2+1 Discharge flexible connectors with clamps 2+1 Blower discharge low flow switches 2+1 Membrane blower isolation valves Biological Equipment

2 Pre-anoxic mixers – 1 per tank 2 Post-anoxic mixers – 1 per tank Fine bubble system for process aeration - loose shipped (with tank downcomer 2 piping, 2 aerobic zones) Submersible RAS pumps, used to transfer mixed liquor from the aerobic tanks to 2 the pre-anoxic tanks - including isolation valves and associated instruments Biological tank controllers, each with associated one (1) pH sensor and one (1)

2 DO sensor MBR ZeeWeed Membrane & Associated Equipment 1 lot Membrane cassette installation assemblies Veolia Confidential and Proprietary Information Proposal #: 557243 Page 10 of 15 9 ZeeWeed 500D 52-module membrane cassettes 396 ZeeWeed 500D 430 ft2 membrane modules 6 Membrane tank level switches 3 Membrane tank level transmitters 3 Pressure transmitters 3 Ejector assemblies Permeate Pump Skid (L1120)

Membrane equipment skids – epoxy-coated carbon steel Each skid includes:

• One (1) permeate pump – reversible rotary lobe pump

• One (1) magnetic flow meter

3

• Two (2) pressure gauges

• One (1) turbidity probe

• One (1) RIO panel

• Associated piping and valves

Backpulse System

- Permeate pumps will also provide backpulse duty

1 Backpulse tank and associated level transmitter and valves 1 Temperature transmitter on the common permeate discharge line RAS Pumps & Associated Equipment 3+1 RAS pump suction isolation valves 3+1 RAS pump suction pressure gauges w/hand isolation valves 3+1 RAS pump suction drain valves 3+1 Centrifugal RAS pumps 3+1 RAS pump discharge pressure gauges w/hand isolation valves 3+1 RAS pump discharge check valves

3+1 RAS pump discharge drain valves 3+1 RAS pump magnetic flow meters 3+1 RAS pump discharge isolation valves Sludge wasting system, including

• One (1) on/of automatic valve

1

• One (1) magnetic flow meter

• One (1) isolation valve

Process Chemical Dosing System 1 Skid-mounted sodium hydroxide dosing system, including 1+1 chemical dosing pumps, and associated valves, instruments, and piping 1 Movable level switch for sodium hydroxide day tank 1 Skid-mounted coagulant dosing system, including 1+1 chemical dosing pumps, and associated valves, instruments, and piping 1 Movable level switch for coagulant day tank 1 Skid-mounted carbon dosing system, including 1+1 chemical dosing pumps, and

associated valves, instruments, and piping Veolia Confidential and Proprietary Information Proposal #: 557243 Page 11 of 15 1 Movable level switch for carbon day tank Membrane Cleaning System 1 Skid-mounted sodium hypochlorite dosing system, including 1 chemical dosing pump, and associated valves, instruments, and piping 1 Movable level switch for sodium hypochlorite day tank 1 Skid-mounted citric acid dosing system, including 1 chemical dosing pump, and

associated valves, instruments, and piping 1 Movable level switch for citric acid day tank 1 Common shelf spare chemical dosing pump Compressed Air System 1+1 Air compressors, each compressor mounted on a horizontal/vertical receiver tank Compressed air assembly (loose shipped) includes:

• one (1) coalescing filter

• one (1) low air pressure switch

1

• one (1) pressure regulator

• one (1) low-low air pressure switch

• associated valves

1+1 Refrigerated air driers and associated valves Electrical and Control Equipment Main control panel (MCP, NEMA12) with Allen Bradley PLC and touch screen 1

HMI

Miscellaneous 1 Membrane cassette lifting bracket General Incl. Equipment general arrangement and layout drawings Incl. Operating & maintenance manuals Field service and start-up assistance (2) - 40 days support over 4 site visits from Incl. Veolia Water field-service professionals for commissioning, plant startup/commissioning, and operator training Incl. 24/7 emergency phone support – 1 year Incl. Veolia insight Basic on-line monitoring service – 1 year

Incl. Equipment mechanical warranty – 1 year Membrane warranty – 10-year pro-rated membrane warranty (2-year full Incl.

replacement warranty and the following 8-year pro-rated membrane warranty) Notes:

1) All Veolia-supplied equipment is designed for installation in an unclassified area except specified

otherwise.

2) Additional field service hours will be billed separately from the proposed system capital cost at a rate

plus living and traveling expenses. Detailed Veolia service rates are available upon request.

3.2 Scope of Supply by Others The following items are for supply by buyer and will include, but are not limited to:

❑ Overall plant design responsibility ❑ Installation on site of all Veolia-supplied skids and loose-shipped equipment Veolia Confidential and Proprietary Information Proposal #: 557243 Page 12 of 15 ❑ review and approval of design parameters related to the biological process and membrane separation system ❑ Review and approval of Veolia supplied equipment drawings and specifications ❑ Detail drawings of all termination points where Veolia equipment or materials tie

into equipment or materials supplied by others ❑ Equipment foundations, civil work, full floor coverage equipment contact pads, buildings, etc.

❑ Receiving, unloading and safe storage of Veolia-supplied equipment at site until ready for installation ❑ HVAC equipment design, specifications and installation (where applicable) ❑ UPS, Power Conditioner, Emergency power supply and specification (where applicable) ❑ Lifting devices including crane able to lift 10,000 lbs for membrane removal, lifting davits, hoists and guide rails for submersible mixers and pumps, etc.

❑ MCC, VFDs, or starters for 3-ph motors, including loose ship Veolia-supplied equipment ❑ 2mm opening fine screen ❑ Equalization tank and associated equipment – as required ❑ Influent pumps and associated valves and instrument ❑ Biological and membrane tanks ❑ All chemical storage tanks, day tanks, and containment ❑ Treated water storage tank – as required ❑ Process and utilities piping, pipe supports, hangers, valves, etc. including but not

limited to:

▪ piping, pipe supports and valves between Veolia-supplied equipment and

other plant process equipment

▪ piping between any loose-supplied Veolia equipment

▪ process tank aeration system air piping, equalization tank system piping,

etc.

❑ Interconnecting pipe between Veolia-supplied skids and tanks (as applicable) ❑ Electrical wiring, conduit and other appurtenances required to provide power connections as required from the electrical power source to the Veolia control panel and from the control panel to any electrical equipment, pump motors and instruments external to the Veolia-supplied enclosure ❑ Suitable, secure remote internet connection for 24/7 emergency telephone

technical support service and InSight remote monitoring & diagnostics service ❑ All bolts, brackets and fasteners to install Veolia-supplied equipment. Seismic structural analysis and anchor bolt sizing Veolia Confidential and Proprietary Information Proposal #: 557243 Page 13 of 15 ❑ Alignment of rotating equipment ❑ Lubricant oil for all rotating equipment ❑ Raw materials, chemicals, and utilities during equipment start-up and operation

❑ Supply of seed sludge for biological process start-up purposes ❑ Disposal of initial start-up wastewater and associated chemicals ❑ Weather protection as required for all Veolia supplied equipment. Skids and electrical panels are designed for indoor operation and will need shelter from the elements.

❑ Laboratory services, operating and maintenance personnel during equipment checkout, start-up and operation ❑ Touch up primer and finish paint surfaces on equipment as required at the completion of the project ❑ All permits Veolia Confidential and Proprietary Information Proposal #: 557243 Page 14 of 15 4 Commercial 4.1 System Pricing Pricing for the proposed equipment and services, as outlined in Section 3, is

summarized in the table below. All pricing is based on the design operating conditions and influent characteristics detailed in Section 1. The pricing herein is for budgetary purposes only and does not constitute an offer of sale. No sales, consumer use, or other similar taxes or duties are included in the pricing below.

Price: All Equipment & Service Z-MOD-L Membrane Bioreactor System, as

$2,780,000 USD

per Section 3.1 4.2 Freight Terms The following freight terms used are as defined by INCOTERMS 2020.

All pricing is CIP project site.

4.3 Equipment Shipment and Delivery Veolia has provided a timeline for the major milestones below. The buyer and seller will arrange a kick-off meeting after contract acceptance to develop a firm shipment schedule.

 Seller: Shop Drawing Package – 12-16 weeks after the PO is accepted o Partial submittals recommended

▪ P&IDs

▪ Mechanical (includes Bill of Material, cut sheets, membrane tank GA)

▪ Electrical

 Seller: Shipment of Equipment – 40-52 weeks from NTP with Manufacture of Equipment (partial shipments allowed)  Seller: Shipment of Membranes – Membranes will ship immediately prior to their installation on-site and commissioning 4.4 Terms and Conditions of Sale This proposal has been prepared and is submitted based on the seller’s standard terms and conditions of sale.

Veolia Confidential and Proprietary Information Proposal #: 557243 Page 15 of 15 Item 7: Denitrifying Filters Budget Proposal

WWTP

Centreville, MD prepared for:

Centreville, MD 5/2/2023 Xylem Water Solutions USA, Inc.

108 Tomlinson Dr Zelienople, PA 16063 Mr. Chris Ball Direct: 724-453-2109 Mobile: 724-713-7145 Email: chris.ball@xylem.com 5/2/2023 Project name : Centreville, MD WWTP Project number : I23178 To Whom It May Concern, Based on your inquiry, we are pleased to forward the following proposal to your attention.

Thank you for the opportunity to offer our equipment and services for the Centreville, MD WWTP.

We hope that our proposal comes up to your expectation. If you have any questions please do not hesitate to contact us.

Respectfully, Chris Ball Senior Sales Engineer 1 Xylem is a leading global water technology provider, enabling customers to transport, treat, test and efficiently use water in public utility, residential and commercial building services, industrial and agricultural settings. The company does business in more than 150 countries through a number of market-leading product brands, and its people bring broad applications expertise with

problems.

meet the demands and challenges of treating water and wastewater. From smarter aeration to advanced filtration to chemical-free disinfection, Xylem leverages its well-known Treatment brands, Flygt, Leopold, Sanitaire, and Wedeco, to offer hundreds of solutions backed by a comprehensive, integrated needs in a number of different industries including municipal water and wastewater, aquaculture, biogas and agriculture, food and beverages, pharmaceuticals, and mining.

Our scientists and engineers utilize their deep applications expertise and continually listen and life-cycle costs, but also promote the smarter use of water.

Leopold has long been a worldwide leader in the water and wastewater treatment industry supplying both filtration and clarification systems. Leopold both designs and supplies systems for gravity filtration, clarification, denitrification, sludge collection and backwash water recovery.

Leopold solutions are ideal for algae, contaminant, and nutrient removal, desalination pretreatment, reuse, SDI, and taste and odor reduction. Since its establishment in 1924, Leopold has pioneered and acquired a number of innovative technologies aimed at improving the quality of water while reducing costs. With over 8,000 installations, customers from around the world have come to rely on Leopold

Since 1924 Leopold has been designing and manufacturing rapid gravity media filtration and clarification solutions for treating water and wastewater.

Xylem, Inc.

www.xylem.com/treatment Leopold supplies potable drinking water treatment plants with media filtration, backwash water recovery, reuse and desalination pretreatment solutions, while supplying wastewater treatment plants with tertiary filtration and denitrification solutions. They also supply both potable and wastewater treatment plants with dissolved air flotation (DAF) clarification, and sludge collection solutions.

Leopold engineers are available to help analyze, evaluate and design all aspects of a complete filtration system, including evaluating influent water qualities, determining optimal loading rates and best design configuration, selecting the best media characteristics, Leopold Filterworx performance filter system comes complete with flume, underdrains, integral media support, engineered media, backwash water troughs,

and system controls. The result is a cost effective, efficient, high-performance system designed to meet customer requirements.

Leopold also offers sludge collection solutions with the Clari- VAC floating sludge collector and the CT2 submerged sludge collector. These systems are used in final clarifiers to remove the sludge solids. For those areas where nitrogen and phosphorus removal is required, Leopold provides elimi- NITE denitrification systems which convert the filters to become biologically active so that the effluent meets the

mandated nitrate and phosphorus levels.

For more information please visit us on our homepage:

http://www.xylem.com/treatment/us/brands/leopold Xylem, Inc.

www.xylem.com/treatment 2

2.1 PROCESS DESCRIPTION

elimi-NITE® Denitrification System General Process Description The elimi-NITE Denitrification System is an attached growth, microbiological process. This gravity, downflow, packed-bed denitrification system is physically identical to a deep-bed downflow sand filter. Denitrifying microorganisms attach to the filter media, which provides the support system for their growth. A carbon source such as methanol, acetic acid, molasses, etc.

is added upstream of the packed-bed filter and a nitrified influent is filtered through the media.

The packed-bed filter system is well suited for denitrification because it provides the necessary hydraulic detention time for the biological reaction to take place. The filter media is composed of a coarse, hard, predominately siliceous material. This media can filter out solids and serve as a support system for the denitrifying microorganisms. The downflow packed-bed system eliminates the requirement for downstream filtration or clarification required of other

denitrification systems.

As denitrification occurs, nitrogen gas accumulates in the filter media, which increases the headloss over the headloss due to the accumulation of solids. The nitrogen gas bubbles are periodically released from the media by taking the filter off line and applying backwash water for a few minutes. This process is called the nitrogen release cycle or filter bumping. The frequency of the nitrogen release cycle is a function of both nitrate removal and a minimum

acceptable time between cycles, typically less than one hour. Usually a filter needs to be bumped once every four to eight hours, again depending on the nitrogen loading rate. The bumps are usually set on a time basis. After a bump the headloss in the filter is reduced or recovered. However, when the liquid level in the filter reaches a designated high level, signifying that the bumps are not effective in reducing headloss, a full backwash is performed

on the filter.

The elimi-NITE Denitrification System is comprised of the following basic principles:

A packed deep-bed layer of sand for biomass attachment and retention of suspended solids A Leopold Universal® Type S®Filter System for distribution of air and water for superior backwashing of the elimi-NITE filter module.

A complete chemical feed system of the carbon source for denitrification (future) Automated backwash sequence and controls optimized for each applications requirement utilizing Leopold FilterWorx Control System.

The full backwash consists of the following sequence:

Influent and effluent valves are closed Waste valve is opened Blower is started Air isolation valve is opened, vent valve is closed and air only wash for approximately one minute Backwash pump is started Backwash isolation valve is opened and air/water backwash for approximately 15 minutes Air isolation valve is closed, vent valve is open and the blower is stopped Xylem, Inc.

www.xylem.com/treatment Water only backwash continues for approximately 5 minutes to purge air from the filter Backwash isolation valve is closed and the backwash pump is stopped Waste valve is closed Influent and effluent valves are opened Gases such as nitrogen or dissolved oxygen will build-up high levels in the filter and cause air binding. In this case the filters are waterfilters from the influent flow, closing the effluent valve, starting the backwash pump, opening the

backwash valve, opening the waste valve (optional if the water depth stays below the effluent launder) and backwashing the filter for approximately 2-5 minutes. This reversal of flow allows the built-up gases to escape the filter. The filter is then put back on-line. The bumps can be programmed to occur either on time or on level and are site specific.

Xylem, Inc.

www.xylem.com/treatment 3

3.1 DESIGN CRITERIA:

The elimi-NITE Denitrification System described here-in is a wastewater treatment system designed for the removal of nitrate-nitrogen.

The elimi-NITE Denitrification System that shall be furnished and installed is described in Section 3.2 - Scope of Supply.

The system has been designed based on specifications using the following criteria:

Plant Flow MGD

AAF 1.00

MMF 1.20

PHF 3.30

Note: Please define the following parameters to help optimize the denitrification process.

The elimi-NITE Denitrification System is based on treating the influent the filters with the following characteristics:

Influent Parameter mg/L Given Assumed Total Suspended Solids (TSS) 30 X ----- Nitrates 8.0 X ----- N-Ammonia ----- ----- ----- Minimum Water Temperature (°C) 12 X ----- The elimi-NITE Denitrification System is designed to achieve the following monthly average effluent quality:

Effluent Parameters mg/L Given Assumed Total Suspended Solids (TSS) <5.0 ----- X Nitrates 1.0 X ----- Total Nitrogen 3.0 ----- X The external carbon source for the elimi-NITE Denitrification System that will be provided by others is methanol.

Xylem, Inc.

www.xylem.com/treatment If Phosphorous removal is required, the phosphorous must be in an insoluble form. This may require the use of coagulants upstream of the Filtration System.

Elimi-NITE Denitrification System Design Criteria Total number of filters Three (3) Active Filtration volume 2,592 ft3 Total filtration area 432 ft2 Individual filter sizing Area 144 ft2 Length 12- Width 12-0" Media Depth Media volume 864 ft3 Media Type Coarse Silica Sand 72 Loading Rates Filter Loading Rate (Three) with one in backwash (Two) At 1.00 MGD 1.61 gpm/ft2 2.41 gpm/ft2

(AAF)

At 1.20 MGD 1.93 gpm/ft2 2.89 gpm/ft2

(MMF)

At 3.30 MGD 5.31 gpm/ft2 7.96 gpm/ft2

(PHF)

Backwash Rates Design concurrent water rate 6 gpm/ft2 Design concurrent air rate 5 scfm/ft2 Design high water rate 6 gpm/ft2 Designed Driving Head 8-0

3.2 SCOPE OF SUPPLY

Xylem Water Solutions USA, Inc will supply only the items specifically detailed within this proposal.

Filter Internals:

Xylem, Inc.

www.xylem.com/treatment Three (3) Complete elimi-NITE filters, 432 square feet effective filtration area total, 12- 2- arrangement including:

432 square feet Leopold Universal® Type XA® Underdrain of the Dual/Parallel Lateral type, manufactured from corrosion resistant, high-density polyethylene supplied with necessary "O"-rings and carbon steel "L" anchor rods and clips. Epoxy, sealant, bonding agents, or other similar materials used during installation are not included and to be provided by others.

432 square feet I.M.S® 1000 MEDIA RETAINER will be furnished. The scope includes molded thermoplastic I.M.S® 1000 media retainer factory installed onto the proposed underdrain block prior to shipment.

Three (3) sets Air Header Assemblies shall be manufactured from schedule 10, type 304 stainless steel pipe. The air header pipe shall measure 6" in diameter and will run the width of the filter cell. The air header shall flange and hardware is to be supplied by others. The air header pipe will have j-risers to provide air to each of the individual filter laterals.

Six (6) WASH TROUGHS: Under this section, we propose to furnish six (6) Leopold Reinforced Fiberglass Troughs, Leo-Lite No. 87, measuring 12" wide x 12" deep x 12'-0" long, round bottom construction. Also included is the standard end hanger assembly fabricated from type 316 stainless steel and type 18-8 stainless steel hardware. Also included with the above troughs are reinforced fiberglass matched-die straight edge weir plates

attached to the troughs with type 18-8 stainless steel fasteners. Also included shall be type 304 stainless steel stabilizers for stabilization of wash water troughs. Wash troughs shall have one closed end and one open discharge end with waterstop.

Media:

2,592 cubic feet Coarse Silica Sand Effective Size: x No. 12 134 Tons FilterWorx Control System:

Under this section, we propose to furnish the following FilterWorx Automatic Control System for the subject project for controlling the filtration and backwashing operations of three (3) filters. The system will consist of the following equipment:

Three (3) Leopold model AFC-5000 Single Filter Control Panels. The panels shall be housed in a NEMA 4X rated, 316 stainless steel enclosure. The panels shall include provisions for the automatic, semi-automatic, and manual control of the filtration and backwashing operations of one (1) filter. Logic functions shall be performed by an Allen Bradley Compact Logix Series PLC. Manual operation shall be independent of the PLC.

Operator interface shall be via an Allen Bradley Panelview Plus 1000 touchscreen and Square D type ZB4 selector switches, pushbuttons and pilot lights.

Xylem, Inc.

www.xylem.com/treatment .

Three (3) Siemens Hydroranger 200 Ultrasonic filter level transmitters One (1) Siemens Hydroranger 200 Clearwell Level Transmitter One (1) Siemens Hydroranger 200 Mudwell Level Transmitter Two (2) Hach Nitratax Sensors and SC1000 Controllers (One Influent & One Effluent) One (1) Hach Dissolved Oxygen Sensor Two (2) Hach Phosphate Analyzers One (1) Siemens 5100W 8 One (1) Lot Spare Equipment consisting of:

One (1) PLC DI module One (1) PLC DO module One (1) PLC AI module One (1) PLC AO module Two (2) of each type of relay, selector switch, pushbutton, and pilot light used.

Automatic Valves:

Under this section we propose to furnish the following 150 lb. Class flanged butterfly valves conforming to AWWA C-504. The valves shall be flanged with EDPM seats, 316 stainless steel shafts and cast iron bodies per ASTM A126. Shaft seals should be self-compensating split V- type or O-ring packing made of BUNA-N per AWWA C-504 class B. The valves shall be supplied with the listed electric operators.

Quantity Function Size Service Three (3) Influent 6-inch open/close Three (3) Effluent 10-inch open/close Three (3) BW Inlet 8-inch open/close Three (3) BW Waste 10-inch open/close Three (3) Air Inlet 6-inch open/close One (1) Backwash Control 8-Inch modulating One (1) Air Vent 2-inch open/close Pumps:

Two (2) Submersible Backwash Pumps. The pumps shall be rated for 864 gpm at an connection and hardware, guide bar brackets and stainless steel lift chains. The pump motor shall be 25 hp, 60 Hz , 460v, 3 phase and have a cast iron housing, volute and impeller. Also included shall be a manual isolation butterfly valve and an air cushioned swing check valve. The stainless steel guide bars shall be supplied by the contractor.

Two (2) Submersible Mudwell Pumps. The pumps shall be rated for 188 gpm at an Xylem, Inc.

www.xylem.com/treatment connection and hardware, guide bar brackets and stainless steel lift chains. The pump motor shall be 6.5 hp, 60 Hz , 460v, 3 phase and have a cast iron housing, volute and impeller. Also included shall be a manual isolation butterfly valve and an air cushioned swing check valve. The stainless steel guide bars shall be supplied by the contractor.

Blowers and Appurtenances:

Two (2) Positive Displacement Blower Packages The blower packages shall be capable of supplying air to the filters during backwash at a rate of 720 scfm. Included with the blower package are TEFC motor, silencer, filter, pressure relief valve, flexible connections, pressure gauges, temperature gauges, discharge check valve and discharge butterfly valve.

The blower shall have a 460 volts, 3 phase, 60 hertz, TEFC motor. An acoustical enclosure will be included.

3.3 SERVICES

The services of a qualified Leopold technical representative to instruct the Contractor's personnel about the proper installation technique of the mechanical filter equipment will be provided for a period of nine (9) days (8 hr/day) on site plus six (6) days travel time to and from the job-site in three (3) trips.

The services of a qualified Leopold technical representative for filter control system startup and operator training will be provided for a period of twelve (12) days (8 hr/day) on site plus eight (8) days travel time to and from the job-site in four (4) trips.

Additional services may be obtained at the current prevailing rate plus living and travel expenses.

Should our service representative be scheduled and arrive on site at the time requested by the contractor/purchaser and the equipment is not ready, our standard per diem rate, plus travel and living expenses will apply.

4

MEDIA:

Submittals:

Materials meet and/or exceed American Water Works Association Standard B100 (latest revision) for Filtering Material. Typical samples and/or test reports detailing the physical and chemical characteristics of the filtering material will be provided for review and approval as required by the specification. If independent testing is required per specification, test reports of the actual material produced will be submitted for approval

prior to release for shipment.

Packaging and Placement of Materials:

Xylem, Inc.

www.xylem.com/treatment Material will be packaged in semi-bulk containers, "Super Bags," with lifting sleeves and bottom discharge spout, containing approximately 2,000 to 4,000 pounds per sack.

Quantities:

Quantities indicated above are Xylem Water Solutions USA, Inc best calculations of the quantity requirements. Loss of gravel due to storage or handling is not covered by this proposal.

ITEMS NOT INCLUDED:

The following items, while not comprehensive, are not included in the elimi-NITE Denitrification System:

Receiving, unloading, storing, and proper installation of supplied equipment and materials.

Concrete for filter, building/architectural work and engineering thereof.

Grout between and under the underdrain laterals in filters.

Platforms, ladders, or walkways.

Lubricants for mechanical equipment.

Interconnecting piping, piping supports, and wall sleeves/pipes including flanges, bolts, nuts, and gaskets.

Instrument air pipe, isolation valves, tubing, and engineering thereof.

Electrical starters, circuit breakers, motor control center, conduit, and interconnecting wiring and engineering thereof, and 480 VAC, 3 phase, 60 HZ power.

Water supply/disposal for flushing of filter internals, media installation or backwash testing.

Lab services for performance guarantee testing.

5

5.1 MAIN SCOPE

BASIS of PRICING:

Any items and/or accessories not specifically called out in this quotation must be construed as being furnished by others.

Xylem, Inc.

www.xylem.com/treatment This quotation is considered firm for 90 days. Orders received more than 90 days after the date of this quotation is reviewed by Xylem Water Solutions USA, Inc before acceptance and is subject to changes in prices or delivery depending on conditions existing at the time of entry. Quoted prices are firm for delivery within 12 months from the delivery date stipulated in the plans & specifications or mutually agreed upon by

Xylem Water Solutions USA, Inc. and Purchase Order issuer at time of order placement.

We do not include any applicable taxes.

Orders resulting from this quotation should be addresses to Xylem Water Solutions USA, Inc. 108 Tomlinson Dr., Zelienople, PA, 16063, USA.

We propose to furnish the material described in this document for a total budget selling price of :

$ .

Pricing for the equipment and field services outlined in this proposal, DAP Jobsite per Incoterms 2020.

For further information pertaining to the equipment contained in this proposal, please contact our area representative, who is:

Sherwood-Logan & Associates, Inc.

2140 Renard Ct.

Annapolis, MD 21401 Phone: (410) 274-3716 Email: AKreider@sherwoodlogan.com Attention: Andrew Kreider Pricing is based on the following payment terms (net 30 days):

10% following initial submittal for approval 80% following the date of the respective shipments of the product 5% following installation, not to exceed 150 days after shipment of the product (whichever comes first) 5% following start-up, not to exceed 180 days after shipment of the product (whichever comes first) 6

6.1 DELIVERY SCHEDULE

6.1.1 Delivery time Delivery of fabricated items and filter media 24 to 45 weeks after drawing approval.

Delivery of filter valves and control 30 to 60 weeks after drawing approval.

6.1.2 Production schedule Xylem, Inc.

www.xylem.com/treatment 8 to 10 weeks after order acceptance.

Submittal of EIC drawings for approval 8 to 12 weeks after order acceptance.

6.2 TERMS AND CONDITIONS OF SALE NORTH AMERICA

This order is subject to the Standard Terms and Conditions of Sale Xylem Americas effective on the date the order is accepted. Terms are available at http://www.xyleminc.com/enus/Pages/terms-conditions-of-sale.aspx and incorporated herein by reference and made a part of the agreement between parties.

Different terms are hereby rejected unless expressly assented to in writing.

AGREEMENT TO PURCHASE: BUYER agrees ACCEPTANCE: SELLER hereby accepts to purchase the equipment and services herein BUYER'S offer to purchase.

in accordance with the terms and conditions set forth above.

________________________________________ Xylem Water Solutions USA, Inc.

(BUYER)

BY:____________________________________ BY:_________________________________

____________________________________ _________________________________

____________________________________ _________________________________

______________________, 20 __________ _____________________, 20 ________

Xylem, Inc.

www.xylem.com/treatment Item 8: UV Disinfection Unit " Centreville WWTP ENR Upgrade and Expansion Preliminary Engineering Report - DRAFT Centreville, MD

Appendix E

Preliminary Hydraulic Profiles Page 102 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231 Whitman, Requardt & Associates, LLP 801 South Caroline Street, Baltimore, Maryland 21231