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Page 96 <br /> However,confirmation sampling of the CYA wells in 1990 did not detect any VOCs. Sampling at a <br /> private well at 8106A Austin Road did find VOCs,and this was confirmed by further sampling. The City <br /> constructed Well No. 14 between the well at 8106A Austin Road and the confirmed plume location in <br /> 1994. Well No. 14 did not encounter the plume. Additional sampling and analysis were determined to be <br /> needed to determine if the plume extends to 8106A Austin Road. A Corrective Action Plan(CAP)was <br /> proposed by the City on April 24, 1991 to address the VOC impacts to groundwater. The plan was <br /> approved by the Regional Water Quality Control Board(RWQCB) staff on June 10, 1991. Two <br /> extraction wells were installed with the capacity to extract about 300 gallons per minute (gpm). The <br /> extracted groundwater was treated through a stripping tower. The treated water was discharged to surface <br /> water(Little Johns Creek)under an NPDES permit. r� <br /> Table K-1 #�dI <br /> Maximum Key VOC Concentrations Reported in 1989 <br /> Compared to Drinking Water Standards <br /> .::ZR, .... <br /> ;> ::«:;:::<; ai cartict <::::> > :::::.aln '41�at �r:: tridat ' <br /> Tetrachloroethene (PCE) 210 5 <br /> Trichloroethene (TCE) 39 5 <br /> cis-l,2-dichloroethene(cis-1,2- 36 6 <br /> DCE) <br /> Vinyl chloride(VC) I 1 0.5 <br /> A 1994 finding of VOC contamination in an agricultural well located on CYA property adjacent to Austin <br /> Road approximately 3,750 feet downgradient of the landfill extended the suspected area of contamination. <br /> Additional Investigations: 1994-1999 <br /> Since the 1994 EIR,various investigations,programs and reports have been completed that have an <br /> impact on the Austin Landfill environmental setting,impacts and mitigation measures. These documents <br /> have either been reviewed by Stellar Environmental Solutions(SES)or discussed with appropriate <br /> responsible personnel to evaluate their relevance to this SEIR. The new information reviewed for this <br /> supplemental EIR is listed below in chronological order: f <br /> ■ Sometime in 1994,the City completed a Surface Water Pollution Prevention Plan (SWPPP). This �SJJ <br /> plan, which was not addressed in the 1994 EIR, stipulated monitoring of surface water runoff <br /> after the first rains, among other things. <br /> ■ In 1995, the City commissioned a Report of Waste Discharge (RWD) for the RWQCB that <br /> described the physical environmental factors, including the groundwater separation, landfill <br /> specifics and operating system. <br /> ■ In the 1994-1995 timeframe, the City started a conjoined effort at household hazardous waste „ <br /> screening, completing a RWD joint technical document. This implemented a 1994 EIR <br /> mitigation measure. <br /> GRASSEI TI ENVIRONMENTAL CONSULTING <br />