Laserfiche WebLink
CALIFORNIA GEOPHIr61CAL GROUP, INC . <br /> 12973 Cree Court , Poway CA 92064 Tel : 486- 1323 • 679- 1114 <br /> 1 of 6 Pages <br /> SITE ASSESSMENT <br /> Gasco Service Station <br /> 749 E . Charter Way <br /> Stockton , CA <br /> February 9 , 1990 <br /> SITE HISTORY <br /> On November 14 , 1989 the following tanks were removed from the <br /> site in accordance with the Tri -Regional Recommendations : <br /> 1 8 , 000 Gal . Unleaded Gasoline <br /> 1 5 , 000 Gal . Super Unleaded Gasoline <br /> 2 5 , 000 Gal . Unleaded Gasoline <br /> A total of 8 soil samples were taken two under each tank and <br /> analyzed for THP , and BTX&E . The lab results previously <br /> reported varied from 1 . 9 to 3600 PPM for TPH . Therefore , it was <br /> resolved that the site is a Case # 1 site and in a Category # 1 <br /> area with the water table located at about 39 feet below the <br /> surface . <br /> The excavation site was backfilled with the original soil plus <br /> soil from a new excavation . The site was then remodeled and <br /> placed back in service . <br /> On Dec . 19 , 1989 an Electromagnetic Induction survey was <br /> conducted on the site to aid the investigation of the areal <br /> extent of the plume and assist in locating the ground water <br /> monitoring wells . <br /> A work plan for assessing the contamination of the site was sent <br /> the the San Joaquin Local Health Department of Dec . 29 , 1969 <br /> along with a well drilling permit . The plan was accepted and a <br /> special well permit was issued on Jan . 19 , 1990 . <br /> Drilling and sampling according to the work plan began on Jan . <br /> 22 , and finished on Jan 26 , 1990 . This report addresses the <br /> data acquired and analyzed according to the work plan , <br /> i ' <br /> GEOLOGY <br /> The site and all nearby terrain are underlain by non -marine , <br /> fine -grained sediments which are tentatively assigned to the <br /> Modesto Formation of Pleistocene age . ( USGS Bulletin 1470 <br /> Marchand and Alwordt , 1981 ) . Although the Modesto is typically <br /> composed of coarser -grained material such as sands and gravels <br /> it is reasonable , on the basis of stratigraphic position , to <br /> consider these finer-grained sediments to be the distal portion <br /> of the large alluvial fans which make up the Modesto . <br /> I, <br />