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HomeMy WebLinkAbout03.b. Review draft Position Paper to authorize Central San staff to sign the agency acceptance letter for plant-specific findings for the Nutrient Reduction Report Page 1 of 16 Item 3.b. CENTRAL SAN BOARD OF DIRECTORS POSITION PAPER DRAFT MEETING DATE: APRIL 25, 2018 SUBJECT: REVIEW DRAFT POSITION PAPER TO AUTHORIZE CENTRAL SAN STAFF TO SIGN THE AGENCYACCEPTANCE LETTER FOR PLANT- SPECIFIC FINDINGS FOR THE NUTRIENT REDUCTION REPORT SUBMITTED BY: INITIATING DEPARTMENT: NITIN GOEL, ASSOCIATE ENGINEER ENGINEERING AND TECHNICAL SERVICES- DAN FROST, SENIOR ENGINEER PDS-PLANNI NG AND APPLIED RESEARCH REVIEWED BY: DANEA GEMMELL, PLANNING & DEVELOPMENT SERVICES DIVISION MANAGER LORI SCHECTEL, ENVIRONMENTAL & REGULATORY COMPLIANCE DIVISION MANAGER JEAN-MARC PETIT, DIRECTOR OF ENGINEERING & TECHNICAL SERVICES ANN K. SASAKI, DEPUTY GENERAL MANAGER ISSUE Board of Directors' authorization is requested for Central San staff to sign the proposed agency acceptance letter for plant-specific findings for the Nutrient Reduction Report. BACKGROUND In 2014, the San Francisco Bay Regional Water Quality Control Board (RWQCB) issued Order No. R2- 2014-0014, Waste Discharge Requirements for Nutrients From Municipal Wastewater Discharges to San Francisco Bay (referred to as the SF Bay Nutrients Watershed Permit). Sections VI.C.1 and 2 of the SF Bay Nutrients Watershed Permit require that the major Dischargers (including Central San) shall, individually or in collaboration with other Dischargers, evaluate options and costs for nutrient discharge reduction by optimization of current treatment work and conduct an evaluation to identify options and costs for potential treatment upgrades for nutrient removal. These provisions of the SF Bay Nutrients Watershed Permit require that the final reports be submitted by July 1, 2018. Over the last few years, Central San has worked with other publicly-owned treatment works (POTW) collaboratively under the joint powers agency- Bay Area Clean Water Agencies (BACWA), and the HDR/Brown & Caldwell consulting team hired by BACWA to submit one coordinated study to meet the April 25, 2018 REEP Committee Meeting Agenda Packet- Page 14 of 84 Page 2 of 16 requirements of Sections VI.C.1 and 2 of the SF Bay Nutrients Watershed Permit. This coordinated study is referred to as the Nutrient Reduction Report. The Nutrient Reduction Report includes individual plant reports and analyses for each of the 37 POTWs that discharge to the San Francisco Bay. The Nutrient Reduction Report and the individual plant reports were prepared using an approach and underlying assumptions that were accepted by the RWQCB as documented in a 2015 Scoping and Evaluation Plan. The findings and recommendations for Central San's individual plant report are summarized in the Executive Summary included as Attachment 1. Each BACWA agency has been requested by the RWQCB to sign a letter accepting the plant-specific findings for the Nutrient Reduction Report. This letter would be included with the Individual Plant Report to be submitted to the RWQCB. Attachment 2 includes the proposed letter that Central San would submit. Central San's current 10-Year Capital Improvement Plan (CI P) includes a future project to complete optimization of the existing treatment plant to reduce nutrient loads if optimizations for nutrient load reduction (i.e. BACWA Level 1 referred to in the reports) are required by the RWQCB within the next 10 years. The current 10-Year Cl P does not include funding projects to meet potential future nutrient limits (i.e. BACWA Levels 2 and 3 referred to in the reports). If nutrient limits are required in the future, Central San's CI P will be updated to include the necessary projects. ALTERNATIVES/CONSIDERATIONS None. FINANCIAL IMPACTS None directly by this action. COMMITTEE RECOMMENDATION The Real Estate & Environmental Planning Committee will review this issue at its April 25, 2018 meeting. RECOMMENDED BOARD ACTION Authorize Central San staff to sign the proposed agency acceptance letter for plant-specific findings for the Nutrient Reduction Report. Strategic Plan Tie-In GOAL TWO: Strive to Meet Regulatory Requirements Strategy 1 - Strive to Achieve 100% Permit Compliance in Air, Water, Land and Other Regulations ATTACHMENTS: 1. Individual Plant Report- Central San Exec Summary 2. Nutrients Watershed Permit- Proposed Central San Acceptance Letter 3. Nutrient Reduction Report Overview Presentation April 25, 2018 REEP Committee Meeting Agenda Packet- Page 15 of 84 BAC W A 1=51 3of16 BAY AREA _� CLEAN WATER Ar A G E N C I E S Brown-n Caldwell Executive Summary The Central Contra Costa Sanitary District (Central San) owns and operates the Central San Wastewater Treatment Plant (WWTP) located in Martinez, CA and discharges treated effluent to Suisun Bay. The plant has an average dry weather flow (ADWF) permitted capacity of 53.8 million gallons per day (mgd). A summary of the flows and loads for the current conditions, optimization, sidestream and upgrade strategies are presented in Table ES-1. Capital costs, operation and maintenance (O&M) costs and unit costs (e.g., $/gpd)were developed for each strategy. Table ES-1. Summary of Costs and Load Reductions Opt. • . Dry Year Dry Year Year - . Season3 Round3 Season3 Round3 - . Basis of Design Rowfor mgd - - 35.5 40.7 53.8 61.6 53.8 61.6 - Strategies Raw to Bay2 mgd 36.3 36.3 36.3 36.3 45.5 45.5 45.5 45.5 - Nutrients to Bay(AverageY AmTwia Ib Nd 7,670 7,670 5,650 5,650 820 770 820 770 - TN Ib Nd 9,050 9,050 8,790 8,790 4,870 4,560 3,680 2,210 - TP Ib P/d 260 260 2807 2807 330 330 240 110 - oStS4,5 Capital $MI - - 7.9 7.9 238 264 391 436 - O&M PV $Nil - - 32.0 32.0 88 96 191 342 - Total FV $Nil - - 40.0 40.0 326 360 582 777 - Unit Cost!P Capital $/gpd - - 0.2 0.2 4.4 4.3 7.3 7.1 - Total P1/ $✓gpd - - 1.1 1.0 6.1 5.8 10.8 12.6 - 1. mgd=n it l ion gallons per day;TN=Total Ntrogen;TP=Total Phosphorus;O&M=Operations and Maintenance;PV=Present Value. 2.The current flays and loads to the Bay are the average annual 2015 BACINA Nutrient Reduction Study Group Annual Repot(data from 7/2012- 6/2015).The reported flaw and loads for optimization,upgrades,and sidestream represent average projected loads discharged to the Bay for the period of analysis(10-yr for optinization and 30-yr for upgrades and sidestream). 3. Dry Season=facilities sized for May 1 through Septen-ber 30 loads but operate year round;year round=facilities sized for year round loads and operated year round.The sidestream facilities are sized for a year round loads and operated year round. 4. Costs are referenced to the ENR SF CG for November 2017 at 12,015.Costs do riot include changes in solids handling or changes in energy requirements in other unit processes.Level 3 costs are inclusive of facilities needed to meet Level 2. 5. PV is calculated based on a 2 percent discount rate for 10 years(optimization)and 30 years(sidestream and upgrades). 6.The unit load reduction cost was calculated by dividing the capital or total present value by the basis of design flaw. 7. If effluent pho�loads are riot a major conoem at the time of optimization,CEPT may riot be required and the effluent TP load would be higher than sham in this table.(i.e.effluent TP loads WWI increase if Optimization Strategy 3 only is implemented). The recommendations included in this report should be considered preliminary and are subject to change. Central San may continue to evaluate potential future nutrient removal alternatives and may further refine the costs and recommendations of this report or may include additional and/or different Bay Area Clean Water Agencies I Central Contra Costa Sanitary District Final Report 11 April 25, 2018 REEP Committee Meeting Agenda Packet- Page 16 of 84 B A C WFcwe4of16 FYZ BAY AREA CLEAN WATER Brown—Caldwell d 11-ft A G E N C I E S recommendations than this report. Other potential options being considered by Central San include supporting recycled water opportunities to divert nutrient loads from Suisun Bay, applied research and piloting of nutrient removal technologies that may provide similar or better levels of treatment at lower present value costs, and other methods of nitrification and nutrient removal that may offer a more feasible implementation. Through secondary process optimization (i.e. implementation of an anaerobic selector) and recycled water use, Central San is already achieving around 85% total phosphorus load reduction of approximately 19,200 Ib P/year (1,600 Ib P/day), around 32% total nitrogen load reduction of approximately 53,000 Ib N/year (-4,400 Ib N/day), and around 9% ammonia load reduction of approximately 9,600 Ib N14-4/year (-800 Ib NH4-4/day) based on 2011-2014 average annual influent and effluent TP, TKN, and Ammonia data. The current optimization strategies require a significant investment ($40M Total PV)to achieve approximately 25% additional ammonia load reduction and less than 3% additional TN load reduction. Table ES-1 assumes that upon further evaluation the optimization strategies will be feasible; however, the recommended strategies require further investigation before determining whether or not they are feasible. The recommended optimization strategy to reduce nutrient loads in the plant effluent includes: 1. Seasonal nitrification and partial denitrification during the dry season. Nitrification would be achieved by increasing the solids retention time (SRT) during the dry season in the activated sludge process. This would require additional blower capacity, alkalinity chemical feed facilities (if required). Partial denitrification would occur in the existing anaerobic selector. Denitrification would likely be limited by return activated sludge (RAS) pumping and a lower than desired hydraulic residence time (HRT) in the anaerobic selector. During the dry season, the existing anaerobic selector will be converted to an anoxic selector and the growth of phosphorus accumulating organisms (PAOs) and corresponding phosphorus removal will be inhibited (i.e. effluent phosphorus loads will increase during the dry season). During dry season startup (for possibly a couple weeks), possible foaming issues and nitrite lock are likely to occur, which may create operational challenges related to effluent quality and recycled water disinfectant demands. Additional recycled water facilities may be required (not currently included in the costs) such as an expansion to the existing sodium hypochlorite facilities and/or an ammonia injection facility. It is recommended that this strategy be further modeled and evaluated to determine its feasibility. 2. If phosphorus removal is of concern, coagulant chemical feed facilities can be included for seasonal phosphorus removal in the primary sedimentation tanks. While the plant already achieves the Level 2 phosphorus concentration, 1 mg P/L, the ability to remove phosphorus in the activated sludge process would go away during the dry season if seasonal nitrification and partial denitrification is implemented. This strategy is predicated on implementation of the next optimization strategy (seasonal nitrification and partial denitrification) and is not recommended as a standalone strategy. Bench and pilot testing is recommended to confirm feasibility prior to implementation. Central San is not considered a candidate for sidestream treatment because the plant incinerates solids, which does not produce a return sidestream laden with nutrients. The upgrade strategies to achieve Levels 2 and 3 include: 1. Level 2 (15 mg TN-N/L and 1 mg TP-P/L): 2 1 Final Report Bay Area Clean Water Agencies I Central Contra Costa Sanitary District April 25, 2018 REEP Committee Meeting Agenda Packet- Page 1 T of 84 BAC W A 1=51 5of16 BAY AREA i� CLEAN WATER A G E N C I E S Brown-nCaldwelL a. Additional primary sedimentation tanks to maintain solids and organics capture in the primary sedimentation tanks. b. Modifying the aeration basins to an Integrated Fixed-Film Activated Sludge (IFAS) process. This would also require additional basins, additional feed pumping capacity, additional blower capacity, alkalinity chemical feed facilities (if required), mixed liquor return pumping/piping, additional RAS pumping capacity, and air piping modifications. c. Relocation of contaminated soils is required to construct the additional IFAS basins required. 2. Level 3 (6 mg TN-N/L and 0.3 mg TP-P/L): a. Same as Level 2, plus b. Add a new denitrifying filter complex to reduce both total nitrogen and total phosphorus loads. This would require a feed pumping station. c. External carbon source chemical feed facilities located at the denitrifying filters to assist with further reducing total nitrogen levels. d. Metal salt and polymer chemical feed facilities located at the denitrifying filters to assist with further reducing total phosphorus levels. Capital costs, O&M costs and present value costs were determined for optimization, sidestream treatment, Level 2 upgrades and Level 3 upgrades. These costs do not account for changes in solids handling requirements, resulting energy impacts in other unit processes, and any costs that may be incurred due to increased greenhouse gas emissions, which may be significant and should be considered when further evaluating the recommendations. As shown in Table ES-1, the costs generally increase from optimization to Level 2 and Level 3 upgrades. The costs generally increase for both capital and O&M from the dry season (operated year round)to year round. Overall the total present value costs range from $40 Mil for dry season optimization up to $777 Mil for Level 3 year-round upgrades. In addition to costs, the relative increase in greenhouse (GHG) emissions was also evaluated. With the exception of chemicals for optimization, the GHG emissions showed an increase as the level of treatment and energy demands increase. The increase in GHG emissions are associated with the production and hauling of chemicals, fugitive biogenic emissions, and emissions due to offsite energy generation and increase import of grid electricity. These increases in GHG emissions are not considered on-site anthropogenic emissions and as such, are not expected to impact Central San's ability to stay below the California Air Resources Board Cap and Trade Threshold. Bay Area Clean Water Agencies I Central Contra Costa Sanitary District Final Report 13 April 25, 2018 REEP Committee Meeting Agenda Packet- Page 18 of 84 Page 6 of 16 ,jIlACENTRAL SAN CONTRACENTRAL • IMHOFF PLACE, MARTINEZ, CA 94553-4392 May 2018 PHONE: (925)228-9500 FAX.- (925)228-4624 www.centralsan.orQ ROGER S.BAILEY Mr. Bruce Wolfe General Manager KENTONL.ALM Executive Officer Coanselfarthe District San Francisco Bay Regional Water Quality Control Board (510)808-2000 KATIE YOUNG RE: ACCEPTANCE OF PLANT-SPECIFIC FINDINGS FOR Secretary of the District THE NUTRIENT REDUCTION REPORT Dear Mr. Wolfe, On behalf of Central Contra Costa Sanitary District (Central San), I have reviewed the individual plant report prepared for Central San that is included as an appendix to the Potential Nutrient Reduction by Treatment Optimization, Sidestream Treatment, Treatment Upgrades, and Other Means Report (Nutrient Reduction Report). The plant report was prepared by the HDR/B&C consulting team (Consultants) under a contract with the Bay Area Clean Water Agencies (BACWA). The Central San report was prepared after the Consultants visited the plant site, interacted with plant staff, prepared a draft report for our staff's review and responded to staff's comments. A representative group of BACWA members (i.e. Contract Management Group) also provided direction to the Consultants in preparing the individual plant reports and the overall summary for the Nutrient Reduction Report. This report represents my best understanding of our facility in 2017. With this level of involvement and oversite of our staff who worked with the Consultant in preparing the report for Central San, I agree that the recommended approach and cost estimates for reducing nutrients at our facility are reasonable with respect to the context of the overall report. Furthermore, in accordance with the Watershed Permit requirement for report certification, I certify, under penalty of law, that this document and all attachments were prepared under direction or supervision of District staff in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Thank you, Ann K. Sasaki Deputy General Manager April 25, 2018 REEP Committee Meeting Agenda Packet- Page 19 of 84 _ fpr r � NUTRIENTS WATERSHED PERMIT — ........-------- NUTRIENT REDUCTION REPORT s � Jean-Marc Petit Director of Engineering & Technical Services Real Estate & Environmental Planning Committee Meeting April 25, 2018 IMF April 25, 2 1 ittee Me - _ BACKGROUND RWQCB issued the SF Bay Nutrients Watershed Permit on April 9, 2014 (effective July 1 , 2014). Special Provision of the SF Bay Nutrients Watershed Permit requires that Dischargers shall, individually or in collaboration with other Dischargers, evaluate options and costs for nutrient reduction to the Bay. The 37 bay-discharging treatment plants are working collectively under the joint powers agency, Bay Area Clean Water Agencies (BACWA), to submit a coordinated study (referred to as the Nutrient Reduction Report). The Nutrient Reduction Report includes individual plant reports that identify plant-specific nutrient reduction strategies and associated costs. THERE IS SOME UNCERTAINTY IN NUTRIENT REGULATIONS Possible Limits (mg/L) Possible Timing-c' Start of End of Ammonia TN TP Watershed Permit - Permit Compliance Required Continued Monitoring, Increased Studies 2019 . 2024 Funding of Science Program & � � . Studies, & Encourage Early Actions Level 1 Optimization 2024? 2029? Level 2 2 15 1 2029? 2034? Level 3 2 6 0.3 2034? 2039? TNA-IT oen. P = TtI h r ` BAY-WIDE NUTRIENT REDUCTION INFRASTRUCTURE WOULD COST BILLIONS OF DOLLARS DRAFT: Total N Discharge Load Reduction and Costs under Various Scenarios (Dry Season Permit) $14,000 70,000 Z $12,000 ------------------------------------------------D-RAFT--------------------------------- --- 80,000 a' _ _ — o M $10,000 - - - --- 50,000 ------------------------------------------------------------------------- -- -- - -- -- ---------------- $8,000 -------------------------------------------------------------------------- ---------- --- 40,000 > $0,000 ----------------------------------------------------------------- ---------- --- 30,000 cu an $4,000 ----------------------------------------------------------------- ---------- --- 20,000 M ------------------------------------------ ----------- $2,000 10,000 Z $0 0 Optimization Sidestream Level Level ■Total PV Cost 13 Load Reduction • Optimization = 10-yr planning horizon • Sidestream and Upgrades (Level 2 and 3) = 30-yr planning horizon using Permitted Capacity AS EXPECTED, SIGNIFICANT COSTS TO ACHIEVE NUTRIENT REMOVAL AT CENTRAL SAN BACWA Level Capital Cost,, O&M Cost'P Present Value, $ Million $ Million $ Million Level 1 $40 for (dry season) $8 $32 10 years Level 2 $264 $96 $360 for (year-round) 30 years Level 3 $778 for (year-round) $436 $342 30 years EXECUTIVE SUMMARY - PLANT=SPECIFIC RECOMMENDATIONS • Optimization Strategy • Seasonal nitrification and denitrification with ammonia injection, alkalinity addition, and increased aeration by addition of new blowers. • UpgradUb LU Meet Luvel ? (2 NH4-N, 15 fN, 1 TP) Modify aeration basins for Integrated Fixed-Film Activated Sludge (IFAS) process, construct additional basins, new feed/RAS pumps, new blowers, and possibly chemical feed. • Additional primary sedimentation tanks. • Upgrades to Meet Level 3 (2 NH4-N 6 TN, 0.3 TP) • Same as Level 2 Plus new denitrifying filters for TN and TP removal, external carbon source for additional N removal and metal salt and polymer feed for additional P removal. • Continue to Evaluate, Pilot, and Explore Nutrient Reduction Alternatives COORDINATION WITH CENTRAL SAN'S CAPITAL IMPROVEMENT PLAN (CIP) Central San's current 10-Year CIP includes a placeholder capital project for Nutrient Removal Optimizations (i.e. BACWA Level 1 ), if required . Nutrient Removal project (i .e. BACWA Levels 2 and 3) are not included in the CIP but have been identified as possible future projects. The 10-Year CIP will need to be updated as Central San continues to track nutrient removal regulations and updates possible nutrient removal strategies. 1 SEE ATTACHMENT 2 FOR PROPOSED AGENCY ACCEPTANCE LETTER CENTRAL SAN May 2018 nays_.f9zsi 289166 D RAFT ` 023)22& 4 Mr.Bruce Wolfe Exeoutive Olficer r�be.fne,e San Frandsco Bay Regional Water Quality Control Board rmx raav RE.ACCEPTANCE OF PLANT-SPECIFIC FINDINGS FOR THE NUTRIENT REDUCTION REPORT Dear Mr_Wolfe, Onbeha If of Central Contra Costa Sanitary Distri ct(Central San),I have reviewed the individual plant report prepared for Central San that is included as an appendix to the Potential Nutrient Reduction by Treatment Optimization,Sidestream Treatment,Treatment Upgrades, and Other Means Report(Nutrient Reduction Report).The plant report was prepared by the HDPJBBC consulting team(Consultants)under a contract with the Bay Area Clean Water Agencies(BAC WA). The Central 5 an report was prepared atter the Consultants visited the plant site,interacted with plant staff,prepared a draft report for our staff's review and responded to staffs comments. A representative group of BACWA members(i.e.Contract Management Grou p)also provided direction to the Consultants in preparing the individual plant reports and the overall summary for the Nutrient Reduction Report This report represents my best understanding of our facility in 2017. With this level of involvement and oversite of our staff who worked with the Consultant in Preparing the report for Central San,I agree that the recommended approach and cost estimates for red uclng nutrients at our facil lty are reasonable with respect to the context of the overs 11 report. Furthermore,in accordance with the Watershed Permit requirement for report certification,I certify,under penalty of law,that this document and all attachments were prepared under direction or supervision of District staff in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who ma nage the system or those persons directly responsible for gathering the information,the information submitted is,to the best of my knowledge and belief,hue,accurate,and complete.I am aware that there are significant penalties for submitting false information,including the possibi lity of fine and imprison Ment for knowing violations_ Thank you, Ann K.Sasaki Deputy General Manager Anril 91i 9njRRFFP ( nm iffizoz NA,=ofinn Pnrin Pnrk-int- Pqnp 97 r)f RA 'goe�--= l RECOMMENDATION Board of Directors' authorization is requested for Central San staff to sign the proposed agency acceptance letter for plant-specific findings for the Nutrient Reduction Report 1 QUESTIONS ?