ARCHIVED REPORTS XR0001225 - Laserfiche WebLink

Home Browse Search

S E C 0 R Conceptual Site Model March 24, 2004 Page 1 1 0 INTRODUCTION SECOR International Incorporated (SECOR), on behalf of Chevron Environmental Management Company (Chevron), presents this Conceptual Site Model (CSM) for Chevron service station 9-2033 k (Site), located at 508 West Charter Way, Stockton, California (Figures i through 3) This CSM was prepared on behalf of Chevron in response to regulatory guidance and comments from San Joaquin „ Environmental Health Department (SJEHD) during a recent site visit and regulatory meeting This CSM presents a discussion of site geology, hydrogeology, surface water, land use, a summary of previous investigations, sources of impacts, potential groundwater receptors, conclusions and recommendations, a work plan, and a scope of assessmentt 1.1 OBJECTIVES <� This CSM has been prepared to evaluate subsurface conditions and to evaluate previous site assessment activities in the vicinity of the Site The specific scope of this CSM is presented below Evaluate local geology and hydrogeology, � • Identify primary sources of petroleum hydrocarbon impacts to soil and groundwater by a , database search conducted by Environmental Data Resources (EDR) and a review of historical reports for underground storage tank (UST) sites in the vicinity of Chevron 9- 2033, • Evaluate soil and groundwater data to delineate hydrocarbon impact to soil and groundwater beneath the subject site, a • Evaluate hydrocarbon impact to soil and groundwater north and east of West Charter Way and South Lincoln Street, respectively, • Propose additional site assessment work 2.0 SITE DESCRIPTION AND FEATURES 4 The site is an operating Chevron service station located in a primarily commercial area at the southwest corner of the intersection of West Charter Way and South Lincoln Street in Stockton, California The site currently contains three gasoline USTs that share a common excavation near the northwest site boundary, four dispenser islands under a common canopy, and a station building (Figure 2) 2.1 Geology The site is in the Central Valley, which is a structural depression (approximately 400 miles long and 20 to 70 miles wide) extending from Redding to the Tehachapi Mountains Water-producing deposits is to the valley are primarily unconsolidated continental deposits (alluvium) of Pliocene age that extend to depths of up to 3,500 feet (USGS, 1998) 1 1Chevton1920331REP0R i S1CSKA\CSM 920'3.1 (REV Ba dor.