ARCHIVED REPORTS_XR0003832 - Laserfiche WebLink

Home Browse Search

Report of Closure Activities 2 Barbara Drake 26485 North Thomton Road Thomton Califomia Ani 16 1998 exposed to a depth of approximately three feet below ground surface(bgs) The casing and well seal were trimmed back to approximately 6 inches above the bottom of the excavation A neat cementlbentonde grout delivered via a tremae pipe was used to backfill the well to the top of casing, and the well excavation area was backfilled with grout to a depth of approximately 2 feet bgs After the grout had set, sod from a clean on-site soil stockpile was used to complete the backfill of the bonng to the surface Wells MW-2 and MW-3,which have histoncally contained varying concentrations of petroleum hydrocarbons,were overdrilled using a truck-mounted, 10-inch-diameter hollow-stem auger dnil ng to a depth of approximately 20 feet bgs The resultant borehole was backfilled to surface with a neat cementtbentonite grout using a tremie pipe placed in the borehole Well-related materials were temporarily stockpiled on-site pending charactenzabon and removal Soil sample WAO, a composite of the cuttings generated from the well abandonment overdnll activities,was obtained and submitted to WEST Laboratory of Davis, a State-certified analytical laboratory The sample was collected and submitted at the same time as, and analyzed for the same parameters as the stockpile soil samples described below Well-related matenals were stockpiled on site, and subsequently removed by W A Craig, Inc (W A Craig), a state-licensed contractor,during work conducted from January 5-12, 1998 23 Soil Stockpile Sampling On September 19, 1997, Fluor Daniel GTI obtained soil samples from the stockpiled soil on-site under direction of the PHS/EHD Pnor to stockpile sampling, an access bore was hand-augered into the stockpile at each sample point(Figure 2) to a sample collection depth of approximately 18 to 24 inches Each sample was collected by dnving a 2-inch-diameter by 6-inch-long brass sleeve, fitted on the end of a slide hammer, Into the stockpile The hand auger and sampling equipment were cleaned between each sampling interval with a phosphate-free detergent and rinsed with distilled water Solis were screened for hydrocarbon vapors using a photo-ionization detector(PED) The sample tube from each sampling point was sealed with Teflon sheets, capped,taped, labeled, and placed on ice In an insulated container The original work scope planned for the collection of 16 separate sod samples which were to be combined Into a total of four composite samples for analysis However, under the direction of Mr Steve Sasson of the PHSIEHD, 17 discrete soil samples were obtained from the sod stockpiles and submitted to WEST Laboratory All samples collected were analyzed for benzene,toluene, ethylbenzene and 20700512 CLO FLUOR DANIEL GTI LJ