Laserfiche WebLink
1 • 06 April 2005 <br /> AGE-NC Project No 98-0448 <br /> Page 2 of 9 _ <br /> 2.0. GROUND WATER MONITORING AND SAMPLING PROCEDURES <br /> 1 <br /> On 07 December 2004,ground water monitoring and sampling was performed at the site on selected ' <br />' ground water monitoring wells Ground water monitoring and sampling procedures for the site were <br /> outlined in Remedial InvestigationlFeasibility Study Work Plan, dated 02 March 1999,prepared by <br /> AGE and approved by the San Joaquin County Environmental Health Department (SJCEHD) by <br />' letter dated 07 April 1999 As-built monitoring well construction details also are summarized in <br /> Table 1 <br /> 2 1 WELL MONITORING AND EVACUATION <br />' During the December 2004 monitoring event, depth to ground water measurements were collected <br /> in monitoring wells MW-1 through MW-8 from the top of the well casing to the nearest 0 01-foot <br /> utilizing a Solmst water level meter, ground water measurements were not collected from well <br /> MW-5 due to a parked vehicle The ground water elevation in each well was calculated by <br /> subtracting the measured depth to ground water from the surveyed casing elevation (Table 1) <br /> rGround water elevations were plotted and contoured on a scaled site map (Figure 3) <br /> After water levels were measured, approximately 3%z to 113/4 gallons of ground water(a minimum <br />' of three casing-water volumes per well)were evacuated(purged)from wells MW-1,MW-2,MW-4 <br /> (A and B), MW-6 and MW-8 utilizing a polyethylene disposable bailer Temperature, pH and <br /> conductivity were measured for stabilization at regular purge-volume intervals from each well using <br /> an Oakton water analyzer Field data and logs are provided in Appendix A Purged ground water was <br /> containerized in properly labeled Department of Transportation(DOT)-approved 55-gallon drums <br /> and was stored on-site in an area lacking general public access <br /> r <br /> 2 2 GROUND WATER SAMPLING <br /> rFollowing well purging,the ground water level in each of the purged wells was allowed to achieve <br /> a minimum of 80%recharge prior to sample collection Ground water samples were collected from + <br /> the purged wells utilizing new, disposable polyethylene bailers and transferred into 40-'ml EPA- <br /> approved volatile organic analysis(VOA)vials containing 0 5 ml 18%hydrochloric acid as a sample <br /> preservative Care was taken to ensure that visible air bubbles-were not present in the vials after <br /> rfilling and capping Ground water sample containers were labeled with the well designation, date, <br /> time, and sampler's initials <br /> r F _ <br /> Advaneed GeoEnvironmental,Inc <br /> r <br />