Laserfiche WebLink
Aven <br /> CV: <br /> 5 fit` 1117 Lone Palm SuiteU6 <br /> %TC <br /> t t, Modesto CA 95351 <br /> 209 579 2221 <br /> Fax 209 579 2225 <br /> A S S O C I A T E S I N C , �L <br /> August 25, 1999 <br /> Mr Harlin Knoll <br /> San Joaquin County Public Health Services <br /> Environmental Health Division <br /> 304 E Weber Ave , Fourth Floor <br /> Stockton, CA 95201-0388 <br /> Subject First Quarter 1999 Monitoring Report, 26056126080 Thornton Road, Thornton, <br /> CA, Site Code 1864 <br /> Mr Knoll <br /> This letter report summarizes field activities conducted during the First Quarter 1999 by ATC <br /> Associates Inc at the subject site (Figure 1) <br /> BACKGROUND <br /> On September 6, 1989, three underground gasoline storage tanks were removed at the project site <br /> by Western Meter Service of Stockton, California Soil samples were collected beneath each <br /> tank and the associated piping Soil samples collected from beneath two of the tanks contained <br /> moderate to high levels of ethylbenzene and xylenes (1 2 to 70 parts per million [ppm]) as well <br /> as total petroleum hydrocarbons as gasoline (TPHg) at 470 to 830 ppm <br /> Due to the presence of elevated concentrations of petroleum hydrocarbons in the tank pit soil <br /> samples, further investigation was required by San Joaquin County Public Health Services, <br /> Environmental Health Division (PHS/EHD) <br /> In a two-phased approach beginning on November 1, 1990, RESNA Industries Inc personnel <br /> advanced six soil borings (MW1 through MW6) to depths ranging from 27 to 30 feet below <br /> grade at the project site to accomplish the following 1) define the lateral and vertical extent of <br /> hydrocarbon impacted soils, 2) determine soil stratigraphy, and 3) install groundwater <br /> monitoring wells within the uppermost aquifer in order to assess groundwater quality The <br /> boring/well locations are plotted on Figure 2 Field methodology and analytical results are <br /> discussed in detail in RESNA's Interim Problem Assessment Report, dated January 13, 1992 <br /> The site's station building and garage were demolished in December 1994 to facilitate corrective <br /> Saction activities including the removal of hydrocarbon contaminated soil which was present <br /> beneath the station building The demolition of the station building was requested in PHS/EHD <br /> W 1625821quart1y\1gr-1999 doc 1 <br />