Laserfiche WebLink
J <br /> ti <br /> j.0 INTRODUCTION owner and <br /> Department(property <br /> uin County <br /> Facilities�Mana9ement Dep lira and <br /> On behalf of the San ,oaq th <br /> responsible party), Ramage Evironmis Soil County.Environmental <br /> nental, Inc. hasprepared <br /> Risk Assessment Report far submittal to the San Joaquin <br /> Human Health Central Valley Regional Water Quality Control Board (RWQCB). <br /> Health Division (EHD) and the <br /> .i. <br /> 1.1 Site Description <br /> The Agricultural Commissioner's Office site is located at 503 East 1e Street in the city of Tracy <br /> L,,i (San Joaquin County), California (Figure 1). The property is an active county office bull6g. <br /> 1. <br /> The site is bordered to the north by Hamilton Alley, a city of Tracy right-of-way, and tot a east <br /> by a transmission repair shop on private property (Figure 2). The site is flat and mostly paved. <br /> ~ Three, 1,000-gallon capacity,'underground_storage tanks (UST) existed in the northeast part of <br /> the site. The northernmost and southernmost USTs (Tanks 1 and 3) were used to store weed <br /> oil (i.e., high-sulfur diesel fuel). The center.UST was-used to store unleaded gasoline. <br /> y 1.2 PreviousWork -` <br /> 1.2.1 'UST System Removal <br /> On October 28, 1988, the three 1,000-gallon capacity„USTs and associatedP <br /> roduct piping in and <br /> P <br /> j <br /> dispenser island equipment were removed"from the site by Tilford & Hall. During UST removal, <br /> the EHD inspector noted the presence of holes in both weed oil USTs and."extensive <br /> i� contamination"within the limits of the excavation. ` <br /> One soil sample was collecte8 from beneath each UST at a depth of 9 to 10 feet below ground <br /> surface (bgs) and analyzed for Total Extractable Petroleum Hydrocarbons (TEPH), Total Volatile <br /> Petroleum Hydrocarbons (TVPH), benzene,.toluene, ethyl benzene and xylenes (STEX), <br /> ethylene dibromide and total lead by Canonie Environmental Services Corporation:, Laboratory <br /> results indicated that concentrations of petroleum hydrocarbons were detected in all three soil <br /> samples. Concentrations of petroleum hydrocarbons included 760 parts per million (ppm) TVPH <br /> beneath the.center UST (Tank 2), 4,700 ppm TEPH from beneath the northern weed oil UST <br /> (Tank 1) and 4,800 ppm TEPH from beneath the southern weed oil UST (Tank 3). The soil <br /> sample analytical results are summarized in Table 1. <br /> k <br /> � - 4 <br />