DRAFT. Palmer Wastewater Treatment Plant Preliminary Engineering Report City of Palmer, Alaska

Transcription

1 City of Palmer, Alaska Prepared by Hattenburg Dilley & Linnell, LLC and G. V. Jones and Associates, Inc. Date:

2 TABLE OF CONTENTS 1.0 INTRODUCTION PURPOSE AND NEED PROJECT PLANNING AREA Location Topography and Geology Vegetation Groundwater Environmental Resources Farmlands Wetlands Wildlife and Fisheries Endangered Species Historical and Archeological Sites Flood Hazards Population Growth Wastewater Flow Projections Population Model Flows Land Use Model Flows Proposed Flows EXISTING FACILITIES Wastewater Treatment Plant History Existing Wastewater Treatment System Existing Sludge Handling Existing Biological Process Current Wastewater Discharge Permit Historical Performance Design Criteria Potential Future Regulatory Requirements Treatment Objectives Projected Wastewater Flow and Strength FINANCIAL STATUS OF EXISTING FACILITIES ALTERNATIVES Alternative 1: Conventional Activated Sludge Description Preliminary Design Criteria Environmental Impacts Land Requirements Cost Estimates Advantages/Disadvantages Alternative 2: Integrated Fixed-Film Activated Sludge Description Preliminary Design Criteria Environmental Impact i

3 6.2.4 Land Requirements Cost Estimates Advantages/Disadvantages Alternative 3: Sequencing Batch Reactor Description Preliminary Design Criteria Environmental Impact Land Requirements Cost Estimates Advantages/Disadvantages Alternative 4: Membrane Bioreactor Description Preliminary Design Criteria Environmental Impacts Land Requirements Cost Estimates Advantages/Disadvantages Alternative 5: Upgrade Existing Lagoons Using Existing Outfall Description Preliminary Design Criteria Environmental Impacts Land Requirements Cost Estimates Advantages/Disadvantages Alternative 6: Upgrade Existing Lagoons with New Outfall to the Main Channel Description Preliminary Design Criteria Environmental Impacts Land Requirements Cost Estimates Advantages/Disadvantages Alternative 7: Upgrade Existing Lagoons with New Percolation Bed Description Preliminary Design Criteria Environmental Impacts Land Requirements Cost Estimates Advantages/Disadvantages Waste Solids Management Screenings and Grit Biosolids Sludge Treatment Alternatives Recommended Sludge Management COMPARATIVE ANALYSIS OF TREATMENT ALTERNATIVES Present Worth Cost Analysis ii

4 7.2 Matrix Rating System FIGURES Figure 1: Location Map... 4 Figure 2: Palmer Project Area Map... 5 Figure 3: Floodplain, Anadromous Waters and Wetlands... 9 Figure 4: Projected Population Growth Rates (Source: KABATA) Figure 5: Projected Study Area Population Figure 6: Wastewater Generated by Zone (Population Model) Figure 7: Sewer Phasing Plan Figure 8: Land Use Map Figure 9: Projected Wastewater Flows Figure 10: Existing Lagoon Site Plan Figure 11: Influent Wastewater Characteristics and Daily Flow (Existing Lagoons) Figure 12: Effluent Wastewater Characteristics (Existing Lagoons) Figure 13: CAS Process Schematic Figure 14: CAS Site Plan with Influent Pumping Figure 15: CAS Site Plan without Influent Pumping Figure 16: IFAS Process Flow Schematic Figure 17: IFAS Site Plan with Influent Pumping Figure 18: IFAS Site Plan without Influent Pumping Figure 19: Sequencing Batch Reactor Process Flow Schematic Figure 20: SBR Site Plan with Influent Pumping Figure 21: SBR Site Plan without Influent Pumping Figure 22: MBR Treatment Process Flow Schematic Figure 23: MBR Site Plan with Influent Pumping Figure 24: MBR Site Plan without Influent Pumping Figure 25: Lagoon Treatment Process Flow Schematic Figure 26: Lagoon Treatment Process Flow Schematic Figure 27: Lagoon and MBBR/DAF Treatment Site Plan Figure 28: Plan View Outfall to Main Channel Figure 29: Details Outfall to Main Channel Figure 30: Lagoon System With Additional Ponds Figure 31: Plan View Outfall to Percolation Bed Figure 32: Details Outfall to Percolation Bed iii

5 TABLES Table 1: City of Palmer Water Sources... 7 Table 2: Projected Residential Area in the Palmer Service Area in Table 3: Wastewater Flows, by Sector (Land Use Model) Table 4: Palmer Lagoon Dredging History Table 5: New and Prior NPDES Permit Limits Table 6: Projected Wastewater Flows Table 7: Palmer Water Sewer Utility Fund Financial Summary Table 8: Palmer Wastewater Rates Table 9: Selected Preliminary CAS Design Parameters Table 10: Selected Preliminary VLR Design Parameters Table 11: Selected Preliminary Design Parameters - IFAS Table 12: Selected Preliminary SBR Design Parameters Table 13: Selected Preliminary MBR Design Parameters Table 14: Design Parameters for Lagoon Upgrade and Existing Outfall Table 15: Design Parameters for Lagoon Upgrade and Main Channel Discharge Table 16: Design Parameters for Lagoon Upgrade & Percolation Bed Discharge Table 17: Comparative Costs Table 18: Criteria Scoring and Weighting Matrix APPENDICES APPENDIX A: APPENDIX B: APPENDIX C: APPENDIX D: APPENDIX E: COST ESTIMATE POPULATION AND WASTEWATER FORECASTS EQUIPMENT INFORMATION MIXING ZONE ANALYSIS PUBLIC MEETINGS iv

6 ACRONYMS ADEC ADF&G ADNR AHRS ANWR AOP ARRC ASCE AWWU BOD 5 C CAS CAT-EX DAF EA EAAS EIS EPA ERWWTF FC FEMA FPPA gfd gpad gpcd gpd gpm HDL HRT HU IFAS ISER KABATA MBR MBBR ME MF Mg mgd MSL NE NEPA NPDES NRCS O&M PER PLC PSA PVDF Alaska Department of Environmental Conservation Alaska Department of Fish and Game Alaska Department of Natural Resources Alaska Heritage Resources Survey Arctic National Wildlife Refuge advanced oxidation processes Alaska Rural Rehabilitation Corporation American Society of Civil Engineers Anchorage Water and Wastewater Utility five day biological oxygen demand Centigrade Conventional Activated Sludge Categorical Exclusion dissolved air flotation Environmental Assessment extended aeration activated sludge Environmental Impact Statement United States Environmental Protection Agency Eagle River Wastewater Treatment Facility fecal coliform Federal Emergency Management Association Farmland Protection Policy Act gallons per square foot per day gallons per acre per day gallons per capita per day gallons per day gallons per minute Hattenburg Dilley & Linnell hydraulic residence time Honchen and Uhlenkott integrated fixed-film activated sludge Institute of Social and Economic Research Knik Arm Bridge and Toll Authority membrane bioreactor moving bed bioreactor Metcalf & Eddy microfilter membrane million gallons million gallons per day mean sea level Northern Economics National Environmental Policy Act National Pollutant Discharge Elimination System Natural Resources Conservation Service Operation and maintenance process logic controllers Palmer Service Area polyvinylidene fluoride v

7 RBC rotating biological contactors RCA Regulatory Commission of Alaska RUS USDA Rural Utilities Service SBR Sequencing Batch Reactor SRT solids retention time SWX Palmer Southwest Utility Extension TSS total suspended solids UA University of Alaska USDA United States Department of Agriculture UV ultraviolet µm microns (1x10-6 meters) WWTP wastewater treatment plant vi