ARCHIVED REPORTS XR0009118 - Laserfiche WebLink

Home Browse Search

t25 January 2005 . AGE-NC Project No 97-0301 Page 2 of 6 2 1 WELLIMgNITORING AND P�U�RI GAWG Aid, On 30 September 004, depth to ground water was measured in each well from the top of the well casing to the nearest 0 01-foot utilizing a Solinst water level meter On 01 October 2004, single-completion monitoring wells MW-1 through MW-5 and multi-level monitoring wells MW-8 through MW-12 were purged by lowering and raising a 3/8-Inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through the top chambers into the specific water-charged screened section A Waterra Hydro-Lift II pump equipped with a mechanical arm was utilized to surge each well with 3/8-inch diameter polyethylene hose Monitoring wells MW-6 and MW-7 were purged using new disposable plastic bailers Approximately 1'/4 to 25%2 gallons of ground water(a minimum of three casing-water volumes per ' well)were purged from single-completion wells MW-1 through MW-7 and approximately 1/3 to 3- gallons were purged from multi-level wells MW-8 through MW-12 Temperature, pH, and conductivity were measured for stabilization at regular purge-volume Intervals from each well using ' an Oakton water analyzer Field data and logs are included in Appendix A All purged ground water was transferred to Department of Transportation(DOT)-approved model 17H 55-gallon drums and • stored on-site in an area lacking general public access 2 2 GROUND WATER SAMPLING After each well was purged, ground water levels were re-measured to verify the amount of ground ' water recharge Upon achieving at least 80%ground water recharge, samples were collected from well s MW-1 through MW-12 utilizing the techniques described above in purging each well Ground water samples from each well were transferred into three 40-milliliter(ml) EPA-approved volatile organic analysis (VOA) vials containing 0 5 ml 18% hydrochloric acid solution as a sample preservative and one 1-liter amber bottle without sample preservative Care was taken to ensure that visible air bubbles were not present in the vials after filling and capping Ground water sample ' containers were labeled with the well designation, date, time, and sampler's initials ' 2 3 LABORATORY ANALYSIS OF GROUND WATER SAMPLES Following collection and labeling,each ground water sample was logged on a chain of custody form, ' placed In a chilled container, and transported to Cal Tech Environmental Laboratories (CTEL), a California Department of Health Services (DHS)-certified laboratory, for analysis for ' Total petroleum hydrocarbons quantified as gasoline,diesel,kerosene,and motor oil(TPH-g, TPH-d, TPH-k, and TPH-mo, respectively)by EPA Method 8015M, and ' Advanced GeoEnvironmental,Inc