Laserfiche WebLink
Water Boards <br /> Central Valley Regional Water Quality Control Board <br /> 18 May 2012 MAY 212012 <br /> Mr. Jeff Baker <br /> Tesoro Companies, Inc. By <br /> 3450 South 344" Way, Suite 100 <br /> Auburn, WA 98001-5931 <br /> OXYGEN INJECTION PILOT STUDY AND WELL DESTRUCTION WORK PLAN, TESORO <br /> STOCKTON TERMINAL, PORT OF STOCKTON, SAN JOAQUIN COUNTY <br /> California Regional Water Quality Control Board, Central Valley Region (Central Valley Water <br /> Board) staff reviewed the following documents: <br /> 27 February 2012 Oxygen Injection)Pilot Study Status Report(Pilot Study Report) <br /> 4 May 2012 Well Destruction Work Plan (Work Plan) <br /> Stantec Consulting Corporation (Stantec) submitted the reports on behalf of Tesoro <br /> Environmental Resources Company (Tesoro) for Tesoro's Stockton Terminal. <br /> On 25 January 2011, Tesoro began a one-year oxygen injection pilot study in wells <br /> TSIMW 3DR and TS/MW-4D to evaluate injecting oxygen into the "D" groundwater zone. The <br /> decreases in(petroleum hydrocarbon concentrations in the treatment <br /> Pilot Study Report shows ation was observed in the downgradient well <br /> wells; however, little change in I <br /> nuing the D zone pilot study for an additional year and <br /> TS/MW-2D. Tesoro recommends cont <br /> increasing the amount of oxygen being injected. <br /> Tesoroing the second and <br /> d quart <br /> of <br /> 12. The <br /> s expanding oses the de truction of 25 o bnerin injection wells and five D zo e m monitoring k <br /> tank farm are$ ing wells that <br /> Plan p P <br /> of the new tank far . Tesoro states that because the wells will be within the <br /> are within the area <br /> containment area, the wells will preset a potential conduit to groundwater following an <br /> accidental release from the tanks. <br /> Our comments are: <br /> one sparge <br /> 1, Central Valley Water Board staff concurs with the destrtan'on of the 25 k farm expansion area. <br /> wells and D zone monitoring wells within the proposed <br /> However, the Workplan proposes destruction of all D zone monitoring wells in the area, <br /> whichTesoro <br /> monitor <br /> n the D <br /> ther keep one xist ng Dzzone mon toring well or inson l <br /> install newzzone mo toringeds <br /> ■ <br />