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HomeMy WebLinkAbout5 Aqua Hydrogeologic Consulting Agenda Item # Memorandum To: Board of Directors From: Ed Taylor Date: September 2, 2005 Subject: Consideration of proposal for water quality testing at Northside Well from AquA Hydrogeologic Consulting. 1. WHY THIS MATTER IS BEFORE THE BOARD According to District code, consulting agreements that exceed $15,000 must be presented to the Board of Directors for approval. Professional services are required for to evaluate the arsenic problem at the Northside Well. 2. HISTORY The USEPA and the Department of Health Services have mandated a new water quality level for arsenic in drinking water, which will take effect on January 1, 2006. The change in the regulation is a decrease level from 50 parts per billion (ppb) to 10 ppb. During the past two years, the District has evaluated and modified wells for compliance with the new regulation. All of the drinking water wells are incompliance except the Northside Well. The Northside Well produces 900 gpm (10%of the total system capacity) and is the number five producer out of the District's eleven wells. The Northside Well has an arsenic level of 47 ppb. Pump testing and zone sampling is required to provide the necessary information to prepare a plan to get Northside Well in compliance with the new regulation. The proposed project will chemical treat the well, test pump and sampling the well every twenty feet to identify what zone or zones the arsenic is coming from. If the tests identify a specific zone, then a plan will be developed to seal off that zone. If the arsenic zones are spread throughout the well and seal them all off will greatly affects the capacity, then a plan for treatment will be prepared. Pump test and sampling requires space for equipment and chemical tanks. Northside Well is the last well scheduled for modification or treatment because of the site constraints caused by the use of the leased space on the site. The space required for the equipment and chemical tanks is large. The project will require five chemical (Baker) tanks. Each tank holds 32,000 gallons and weights when full, 260,000 lb or 130 tons. z 3. NEW INFORMATION The lease of the space was up on July 31, 2005. The Board extended the lease to the end of September 2005. The Northside Well is not to be used for drinking water after January 1, 2006 if it does not comply with the new arsenic regulations. The Northside Well is an important water source for the District. It is imperative that the test pumping and sampling project be complete as fast as possible, so that the modifications or treatment for the well is complete before 2006. To accomplish this, the testing must start October 3, 2005. AquA Hydrogeologic Consulting will subcontract the test pumping to Carson Pump and the water laboratory test to Sierra Environmental Monitoring. This project is in the 2005 budget. 4. RECOMMENDATION I recommend that the Board approve the proposal from Aqua Hydrogeologic Consulting for Northside Well rehabilitation and arsenic sampling program in an amount not to exceed $61,070.00. A, WSW Y September 2, 2005 Mr. Ed Taylor Water Utility Manager Truckee Donner Public Utility District P.O. Box 309 Truckee, CA 96160 RE: Northside Well rehabilitation and water sampling programs Dear Mr. Taylor: As you requested, I have prepared the following scope of work and cost estimate for providing hydrogeologie consulting services for maintenance and water quality sampling of the Northside well. The following is the proposed work plan as submitted by AquA. Work Plan Cleaninp0amalina of the Northside Well • During the well maintenance program AquA personnel will be on-site during installation and removal of the muriatic acid. Aqua will subcontract to Carson Pump for maintenance work. • AquA will provide on-site supervision and data collection during the double swab pumping of each interval where the water quality sample is to be collected. It is estimated that 20 samples will be collected. The samples will be submitted to Sierra Environmental Monitoring for arsenic analysis. • Based on results of the water quality analysis for arsenic, a program will be developed to either seal off the zone or zones which are contributing high arsenic values to the well or define the levels of water treatment necessary. • A final report will be prepared documenting all field activities and water quality results from the laboratory. Project Total Not to Exceed $61,070 If you have any questions regarding this proposal, please contact me at (775) 250- 9700. Sincerely, David Carlson Ro.Box 18793 Reno,NA 89511 (775)250 9700*Fax(775)852-3642 odm id aquagroundr+ateceom*k<kN".aquagmundrratecean