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Page 2 of 3 farther than benzene travels in groundwater on average, at gasoline release sites of all sizes as documented in the Technical Justification for Groundwater Plume Lengths, Indicator Constituents, Concentrations, and Buffer Distances (Separation Distances) to Receptors; State Water Resources Control Board; July 2011, http://www,waterboards.ca .gov/ust/policy/techoust07l211 . pdf top of page 2 . There is no evidence to suggest that potential historic releases from Tracey Country Market's small, gas tanks would come close to what is generally considered an "average" sized release as discussed in this document. Furthermore, the soil sample data we have at the Country Market site, which was collected in the immediate vicinity and directly below the UST's shows no evidence of a release capable of reaching groundwater ( reported at 78 feet , 1974 DWR well install report), let alone migrate down gradient another 300 feet. The soil samples collected beneath the LISTS were non-detect and as we discussed in October, the highest concentrations of BTEX compounds detected at the site in the samples located adjacent to the tanks, are already below concentrations that would warrant further risk evaluation . In addition, the on-site domestic well that Antea Group already sampled is active, is the closed potential receptor to the potential release point, and can reasonably be expected to draw in residual hydrocarbon concentrations in groundwater, if they were present. That sample was also non-detect. Therefore, based on this additional information and further evaluation, Antea Group reiterates our recommendation and request that this case be closed with no further action . Sincerely, Andrew M . Lojo, P.G . 6034. Links to reports documenting regional GW flow direction to the north or northwest. "Based on groundwater elevations collected during December 2001, the groundwater appears to be flowing to the northwest with a gradient of approximately 0.001 foot per foot (ft/ft) ." RAP for Pyrolytic Oil- and Metals-Affected Soil Tracy Tire Fire Site September 18, 2003 http ://www.envirostor.dtsc.ca .gov/regulators/deliverable documents/5660034000/Tracy%20Tire%20Fire% 20RAP%209 18 2003 . pdf "Based on depth to water measurements recorded during ground sampling events from 2003 through 2006, groundwater within the upper waterbearing unit generally flows toward the north-northwest with a calculated gradient ranging between approximately 0.001 to 0.002 feet per foot (ft/ft) ." Letter of Transmittal from LFR Environmental Management and Consulting Engineering November 10, 2006 http://www.envirostor.dtsc.ca .gov/regulators/deliverable documents/4871686637/combined-rpt-RA summ- Nov06-revfinal-09025. pdf "Based on file reviews of surrounding properties, groundwater flows northward in this area"; DTW reported at 75' bgs Soil and Groundwater Investigation ReportTAOC Tracy Gravel Pits October 2006 http ://geotracl<er.waterboards.ca .gov/esi/uploads/geo repo rt/3204346656/SL0607723732 . PDF Andrew Lojo P.G. 1 Senior Consultant I USA 12/18/2014