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1 <br /> INTRODUCTION <br /> This Project Status Report of Groundwater Monitoring provides groundwater quality monitoring <br /> information and data for gasoline impact from 2 former 12,000-gallon USTs The groundwater <br />' monitoring activities discussed herein were conducted in general accordance with the "Workplan <br /> for Initial Subsurface Investigation," (Boyajran & Ross, Inc [B&R], 1998) "Initial Subsurface <br /> Investigation of Petroleum Hydrocarbons," (B&R, 1998), and the "Workplan for Additional <br />' Subsurface Site Investigation for Petroleum Hydrocarbons,"(Phrlsp P Ross, R G Consulting <br /> Hydrogeologist, January 10, 1999) implemented as approved by the San Joaquin County <br /> Environmental Health Division(SJCEHD) <br />' The work described in the Groundwater Monitoring section documents sounding and sampling <br /> activities conducted on August 20, 2002 (third quarter, 2002) <br />' The History of Site Work (beginning on page 2) summarizes previous work performed on the <br /> subject site, as do the tables listing well-sounding data, and groundwater sampling analytical <br />' results Previously-submitted documents by the Port of Stockton (Port), and earlier consultants <br /> present historical information in greater detail <br />' SITE SETTING <br /> The property is located at the central portion of the Port in the City of Stockton, San Joaquin <br /> County, California (see Figure 1) This site, along with Site 2, has been identified by SJCEHD as <br />' "Site Code 1282-124 " Site 2 was determined to require no further investigations by SJCEHD <br /> Site 3 is approximately 50 feet north of Port Road G and about 300 feet west of Port Road 14 (see <br /> Figure 1) Following is a description of the tanks, as well as excavation, soil, and groundwater <br /> ' sampling activities at Site 3, which is the subject of this report <br /> The site formerly contained two 12,000-gallon tanks, identified on a SJCEHD inspection report as <br />' Tank #1 and Tank # 4, both of which stored unleaded gasoline The tanks were removed on <br /> February 16, 1988 by Stockton Service Station Equipment Co , Inc (SSSE) Approximately 180 <br /> cubic yards of soil were excavated with the tanks to a depth of about 11 feet below surface grade <br /> ' (bsg) Presently, the area over the former tanks and excavation is covered with concrete A survey <br /> of domestic, municipal, agricultural, industrial and other supply wells within a 2,000-foot radius of <br /> the site was conducted No municipal or drinking water supply wells were identified within the <br /> ' 2,000-foot radius <br /> ' LOCAL HYDROGEOLOGIC SETTING <br /> The site is located on the Delta of the San Joaquin River, approximately 2 miles east of the <br /> ' confluence of the San Joaquin and Calaveras Rivers The subsurface geology consists of a thick <br /> • sequence of alluvial deposits of late Tertiary to Holocene Age, overlying sedimentary rocks of <br /> Cretaceous to Tertiary Age, which in turn overlie crystalline basement rocks (Bartow and Nilsen, <br /> ust sne3 gtrl2 doe 2 <br />