ARCHIVED REPORTS XR0001920 - Laserfiche WebLink

Home Browse Search

4 , 23 July,2001 • AGE-NC Project No 97-0312 I Page 2 of 4 2 S e 4 I a Grundfos submersible purge pump Approximately 85 gallons of water were purged from UST-1 ` and approximately 8 to 12 gallons of water were removed from wells UST-2 through UST-6 (a minimum of three standing casing-water volumes per well) Ground water was purged from near the u I top of the water column to remove water trapped within the unscreened interval of the well casings Temperature,pH and conductivity ofpurged water were measured at regular intervals during purging a using an Oakton water analyzer The recorded field data and logs are included in Appendix B IPurged water was stored on-site in 55-gallon DOT-approved drums pending laboratory analysis On 18 June 2001 the small and large domestic wells on-site were sampled for volatile organic ' compounds To purge the large domestic well, a dram valve was opened on the water storage tank The pump was allowed to cycle,on and off for approximately 15 minutes To purge the small ` domestic well, a faucet between the well and the water holding tank was opened to fallow the pump ' to cycle for approximately 15 minutes t I23 COLLECTION OF GROUND WATER SAMPLES s lie The depth to water was re-measured following purging to assure a minimum of 80% recharge prior to sampling Water samples were retrieved from each purged well using new disposable bailers To sample the domestic wells, a sampling port was opened at the well head and samples were collected ' from the sampling port while the pump was operating to obtain fresh water samples Each sample was transferred into three laboratory-supplied 40-m1 EPA-approved VOA vials containing 0 5 ml of 18% hydrochloric acid as a sample preservative and into one 1-liter amber bottle without ' preservative The samples were labeled,placed in a chilled container and transported under chain-of- custody to McCampbell Analytical Inc (MAI) in Pacheco, a California Department of Health , Services (DHS)-certified analytical laboratory The samples were analyzed for E • Total petroleum hydrocarbons quantified asgasoline (TPH-g) and diesel (TPH-d) m S accordance with EPA Methods 5030/8015m and 355018015m, respectively, ' ' • ` Volatile aromatic hydrocarbons - benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 80201602, and ' Volatile organics and fuel oxygenates,--MTBE, di-isopropyl ether (DIPS), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME) and tert-butanol (TBA) in accordance with EPA Method 8260 modified F n ' F'IlVDINGS 3.0. • Ground water elevations were determined by subtracting the measured depths-to-water from the 1 F , Advanced GeoEnvYronni Mai,Ine ` 1 V f ' -