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Home My WebLink About2024-02-20 Council meeting -Water Supply Strategies (2)WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.WATER SUPPLY STRATEGIESApprove Water System Study Findings, Recommendations and Next Steps WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.WATER SUPPLY STUDIES1.Well 2 Treatment for PFAS (Authorized on September 5, 2023).2.Water Distribution System Modeling for New Water Supply Source Locations(Authorized onSeptember 5, 2023).3.SouthArea Water Treatment Plant (WTP) for Future Wells (Authorized on October 17, 2023).4.Revised Capital Improvement Plan for Neighborhood Connections to City Water. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.FINDINGSWELL 2 TREATMENT FOR PFAS1) Well 2 production capacities are needed to meet peak summer demands untilWell6isoperational.2) Temporary IX treatment for PFAS at Well 2 is feasible.3) Permanent IX treatment for PFAS at Well 2 is dependent upon further evaluation and MDHapproval for long-term use of a pressure cartridge filter for iron and manganese (Fe/Mn)pretreatment.4) Treatment for PFAS at Well 2 using granular activated carbon (GAC) filter media is notfeasible.Limitedby building footprint and lack of sanitary sewer.5) Prefabricated trailer mounted systems are available for use in 2024.1) Evoqua: 450 gpm IX filters, six vessels per trailer, only one trailer available for 2024 (min. 6-mo. rental). Costs: $260kinitial fill and startup, $15k/mo rental, freight and demobilization at cost+30%2) WaterSurplus: 650 gpm IX filters, eight vessels per trailer, multiple trailers available for 2024. Costs: $141k initial filland startup, $27k/mo (two year rental rate), $3k demobilization. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.RECOMMENDATIONS WELL 2 TREATMENT FOR PFAS1) Proceed with design phase engineering for an Anion Exchange (IX) TreatmentatWell2usingpaired 8-ft diameter steel pressure vessels within the existing buildingfootprint and raisedroof. The roof needs to be raised to accommodate the 15-ft. tall steel pressure vessels.2) Pretreatment for IX filtration is required. A pressure cartridge filter for iron and manganese(Fe/Mn) pretreatment is recommended.3) Secure a GrantAgreement Amendment to fund design phase engineering services.4) Obtain sampling and detailed testing of Well 2 for design purposes.5) Proceed with direct procurement of the treatment vessels/equipment for accelerated delivery.6) Operate Well 2 on emergency basis only through peak 2024 summer demands.We are notrecommending the trail er mounted rental filters for use in 2024.7) Initiate building modifications as early as Summer 2024 in preparationof treatmentequipment.8) Initiate Well 2 rehabilitation and pump replacement in Fall 2024. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.PROJECT DETAILSWELL 2 TREATMENT FOR PFAS1) Treatment capacity is 800 gpm. Limited by building and site footprint.2) Schedule. Treatment system to be online by Spring 2025, prior to peak water demands.3) Cost. $2.40 million. All equipment is by purchased (no rentals).4) Expected life of IX media between replacement is estimated at 2-4 years.5) Estimated IX media replacement costs, including wastewater and media disposal is $225,000per change-out ($150k media, $55k disposal, $20k labor).6) Expected service life of treatmentsystem equipment is 50+ years (repaint interior and exteriorof vessels every 20 years). The equipment has a salvage or resale value within the design life.7) Temporary IX treatment for PFAS at Well 2 is feasible. Permanent IX treatment for PFAS atWell 2 is dependent upon further evaluation and MDH approval for long-termuse of apressure cartridge filter for iron and manganese (Fe/Mn) pretreatment. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.PROJECT DETAILSWELL 2 TREATMENT FOR PFAS1) Building modifications include process piping, fittings, valving andmeters; removal ofhydropneumatic tank, air compressor and associated small piping systems; replacement ofwest side exterior “knock-out” block wall; sealing the generator room grated windowopenings, installation of exterior wall insultation and unit heaters, and revision of accessdoors.2) Building modifications also include removal of the interior wall, raising the roof byincreasing the exterior wall heights, and pouring concrete pads for the steel vessels. A newdouble wide 16-ft. tall garage door would be installed.3) Chemical feed equipment modifications will be required .4) Electrical and control modifications will be required.5) Replacement back-up generator is recommended.6) Well rehabilitation and new well pump with a variable frequency drive (VFD) isrecommended. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.QUESTIONS? WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.WATER DISTRIBUTION MAPNorthern Water Supply PlanWell 6 & 7 Northern Water Supply PlanWell 2Well 4Well 5 WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Well 6 & 7 Southern Water Supply Planwith TreatmentWell 2Well 4Well 5WATER DISTRIBUTION MAPSouthern Water Supply Plan WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Option A1: Systemwide Delivery with North Wells (Wells 4 and 5) and South WTP (for Wells 6 and 7).Option A1 Works really Good WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Option A2: Option A1 with North WTP for Wells 4 and 5 (combining delivery point).Option A2 Works really Good WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Option C2: SPRWS Systemwide Delivery with Southern Connection Point (HPZ).Option C2: Recommended for SPRWS system wide delivery. Requires Booster Station PRV andoperational adjustments. It is recommended to construct a dedicated transmission line to theIntermediate Pressure Zone (Water Tower 2). WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Option C3: Separate North (IPZ) and South Water Delivery System (HPZ & LPZ).North WTP for Wells 4 and 5 (combining delivery point).SPRWS Southern Connection Point.Option C3: Separate North and South water delivery system works well. Allows for opportunity topurchase SPRWS for South Water Delivery System and maintain Wells 2, 4 and 4for North waterdelivery system. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.WATER DISTIRBUTION SYSTEM MODELING FOR NEW WATER SUPPLY SOURCE LOCAITONS1. Adopt a revised Water System Plan to construct and operate a systemwide water supplydelivery system with North Wells (Wells 2, 4 and 5) and South WTP (for Wells 6and 7) –OptionA1.2. Work closely with MDH to test and monitor PFAS at Wells 4 and 5. If PFAS exceedance isdetermined, initiate the design and construction of a centralized Water Treatment Plant to beconstructed at Tana Ridge Park to treat both Well 4 and Well 5. Initiate raw watermain anddistribution system infrastructure improvements recommended forAlternative A2. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.QUESTIONS? WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.Well 6 & 7 Southern Water Supply Planwith TreatmentWell 2Well 4Well 5WATER DISTRIBUTION MAPSouthern Water Supply Plan WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.WATER DISTRIBUTION MAPOther possible Well/Treatment LocationsWell 2Well 4Well 5 WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.A permanent water treatment plant (WTP) and construction of Well 6 at Stonegate Park isfeasible. The full use of the park for recreational purposes will be lost with the exception ofthe playground equipment. The property is city owned.A permanent water treatment plant (WTP) and construction of Well 6 just north of 10th Streetand the Inwood subdivision is feasible. Property will need to be acquired.A ComprehensivePlan Amendment will be required to extend sanitary sewer to the WTP and to revise thezoning from RAD to Public Facilities.The Public Works Facility site resides within the White Bear Lake Court Order 5-mile radiusand is therefore not feasible.Apermanent water treatment plant (WTP) should be constructed with an initial 3,000 to 4,000GPM capacity to serve at least two water supply wells (Well 6 and Well 3 or 7).The treatmentplant should be designed to allow for expansion for 1 additional water supply well and shouldbe designed to meet the projected 2024 Water Supply Demands.It is recommended that the water treatment plant (WTP) be designed to include pretreatmentfor iron and manganese (Fe/Mn).FINDINGSSOUTH AREA WATER TREATMENT PLANT (WTP) WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.A pilot study is recommended to inform the water treatment plant design parameters and tooptimize the treatment design. The total estimated cost for a pilot study is in the $250,000 to$350,000 range and can take approximately six to nine months to complete.When pretreatment for Fe/Mn is provided, IX media has demonstrated greater treatmentcapacity compared to GAC during pilot studies performed on similar water quality. IX mediatends to have greater efficacy for removing certain PFAS compounds that are present in LakeElmo’s water supply.Assuming an April 16, 2024 design authorization for Well 6 and the South Water TreatmentPlant, the plant will be operational for peak 2027 summer water supply demands. Thisassumes a 36-month design and construction schedule. Depending on the commencement dateof the pilot study, and the initial findings, the completion date for the WTP could be extendedby six to nine months.The opinion of probable cost for the treatment facility is $45M including a20% contingencyand soft costs.FINDINGSSOUTH AREA WATER TREATMENT PLANT (WTP) WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.1. Secure a MPCA Grant Agreement Amendment to fund design phase engineeringservicesandthe construction of a Test Well and Stonegate Park.2. Initiate Project design and construction phase services.3. Proceed with design phase engineering for Well 6 and a PFAS Water Treatment Plant to belocated in the south part of the city in the high-pressure zone.1. Consider Stonegate Park2. Consider sites north of 10th Street.4. Proceed with detailed site layout and investigations including the construction of a Test Well.5. Consider initiation of a pilot plant study to optimize the WTP design.6. It is recommended that the water treatment plant (WTP) be designed to include pretreatmentfor iron and manganese (Fe/Mn).RECOMMENDATIONSSOUTH AREA WATER TREATMENT PLANT (WTP) WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc. WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.QUESTIONS? WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.2024 – Homestead (18)20252025 -- Packard Park/Eden Park/20thSt Cir (68)20262026 -- Tartan Meadows/Klondike (39)20272027 -- Downs Lake/Sunfish Ponds/Forest (54)2028NEIGHBORHOOD CONNECTIONS WATER SUPPLY STRATEGIES – NEXT STEPSFEBRUARY 20, 2024 FOCUSENGINEERING, inc.RECOMMENDATIONS / REQUESTED COUNCIL ACTIONStaff is recommending that the City Council approve the preliminary findings andrecommendations as presented at the Council meeting, or as amended by the Council, and directstaff to initiate preliminary and final designs for improvements as recommended, and to apply forthe applicable 3M Settlement Grant Funding through the MPCA.“Move to approve the preliminary findings and recommendations as presented at the Council meeting, or as amended by the Council, and direct staff to initiate preliminary and final designs for the improvements as recommended, and to apply for the applicable 3M Settlement Grant Funding through the MPCA.”