Laserfiche WebLink
California Regional Nater Quality Control Board <br /> Central Valley Region <br /> }Carl L Longley,SeD,PX,Chair <br /> asda S Adams Sacramento Main <br /> Arnold <br /> 1.7f- i 1020 Sun Cen Drive 9200,Rancho CWiRm 956'10-61,14 � Schwa r <br /> nvirarrrtento/ Phone(1916,464-3291-FAX{916)464-4W Governr <br /> ` Protect#on bttpt/hvww,wateftards.cagovfccnuWalky <br /> 14 December 2007 <br /> Mr. Kevin Basso <br /> General Manager- Forward Inc. <br /> 1145 West Charger Way <br /> Stockton, CA 95206 <br /> FORWARD LANDFILL HISTORIC HIGH GROUNDWATER,AREA EAST OF WMU F 6, <br /> SAN JOAQUIN COUNTY <br /> Regional Water Board staff has reviewed the "Forward Landfill Groundwater Elevation <br /> Evaluation East of Waste /Management Unit FU-06"and the"Forward Landfill Expansion, <br /> Groundwater Elevation Evaluation"submitted on 30 November 2007 and 11 May 2007 <br /> respectively. The reports evaluate the highest anticipated groundwater elevation underlying <br /> Forward Landfill, east of FU-06 and the proposed future expansion area respectively. The <br /> reports demonstrate that groundwater levels in the Forward area dropped forty to sixty feet <br /> between 1949 and 1974 and since 1974 fluctuate within a range of thirty fleet. The maximum <br /> high groundwater levels since 1974 occurred in the spring of 1964. if spring 1984 conditions <br /> were to reoccur, the maximum high groundwater elevation underlying the area east of FU-06 <br /> is anticipated to be minus 6 feet mean sea level (msl). <br /> Title 27 Section 20440(c) states: "Alt new landfills, waste piles, and surface impoundments <br /> shall be sited, designed, constructer!, and operated to ensure that wastes will be a minimum of <br /> five feet(5 ft.) above the highest anticipated elevation of underlying groundwater." Staff <br /> concurs that minus 6 feet msl is a valid estimate of the highest anticipated groundwater <br /> elevation for the area east of FU-06'. Therefore,waste in the area east of FU-06 may not be <br /> discharged below the elevation of minus 1-foot msl and waste containment units constructed <br /> east of FU-06 must be designed accordingly. Also, liner components that are constructed at <br /> or below the highest anticipated groundwater elevation should be protected from flooding or <br /> damage by upwelling groundwater. <br /> Existing Waste Discharge Requirements (WDRs) Order No. R5-2003-0049 prohibits discharge <br /> of waste below 7 feet mist. Staff understands that CEQA for landfill expansion will be complete <br /> in approximately one year and anticipates that revised WDRs will be adopted at that time. <br /> Revised WDRs incorporating the minus 1 feet msl limit for the area east of FU-06 must be <br /> adopted before waste can be discharged below 7 feet rnsl. 'Therefore,the 200a waste unit <br /> must be constructed to comply with existing WDRs. <br /> California Enviromnental Protection Agency <br /> ltwyclett Pdper <br />