Laserfiche WebLink
. 1419 Charter Way, Stockton <br /> Stefsnos Gasoline <br /> August, 2004, Page 2 <br /> The deepest grab groundwater sample on site was collected from cone penetrometer testing <br /> boring CPT-1 at 60 feet below surface grade (bsg) in December 1999 Analytical results of <br /> the CPT-1 grab groundwater sample were 5,700 micrograms per liter (ug/1) of Total <br /> Petroleum Hydrocarbons as gasohne (TPH-g), 76 ug/l of benzene, and 11 ug/l of 1,2- <br /> dichloroethane (1,2-DCA) All three monitoring wells on site MW-1 to MW-3 are screened <br /> from 30 feet to 50 feet bsg Although deeper groundwater samples have been collected and <br /> analyzed off-site,the vertical extent of the groundwater contamination plume on site has not <br /> been defined Analytical results of the grab groundwater samples from CPT-4,which is the <br /> collection point furthest to the east,were 100 ug/1 of TPH-g and 36 ug/l of 1,2-DCA at 75 <br /> feet bsg The CPT-4 grab groundwater sample results were all non-detect at 120 feet bsg <br /> The vertical extent of the groundwater contamination off-site appears to be defined at this <br /> time, but the lateral extent of the groundwater contamination to the east is not defined <br /> Submit a work plan to EHD that will define vertical extent of the groundwater <br /> contamination on slte, and the lateral extent of the groundwater contar=atxon off Site by <br /> October 20,2004 If you have any questions, please contact Jeffrey Wong at (209) 468- <br /> 0335 <br /> Donna Heran, REHS, Director <br /> Environmental Health Department <br /> Jeffrev Wong, Senior RENS - V �Llargar Lagoxio, REQS <br /> LOP/Sate Nlitigation Urut IV Supervisor <br /> C RWQCB, Central Valley Region—James a. L Barton, RG <br /> C Advanced GeoEnvironmental, Inc —Donna Sexton <br />