Laserfiche WebLink
Geologccal7-ecknccs Inc Page 4 <br /> 1 Groundwater Monitoring Report <br /> Project No 770 2 <br /> April 30,2003 <br /> well MW-5 contained product sheen The wells were purged of at least three well volumes <br /> of stagnant water using a dedicated Waterra check-ball assembly and 'h inch tubing <br /> ' Purging continued until the temperature, conductivity and pH of the groundwater stabilized <br /> (c10% variation among three readings) indicating that formation water representative of <br /> aquifer conditions was entering the wells These water quality parameters were measured at <br /> ' intervals of each well volume purged <br /> ' Once purging was complete, a water sample was collected from the Waterra tube Care was <br /> taken to minimize sample agitation Once the sample container was filled and capped, the <br /> bottle was inverted, tapped and checked for headspace bubbles The sample container was <br /> identified and labeled with a unique designation, inserted into foam holders and placed into <br /> an ice chest cooled to 4°C for transport to the laboratory <br /> ' All non-disposable sampling equipment was decontaminated using a hot water washer and <br /> detergent before and between uses Disposable gloves were used by the technician to <br /> collect all samples and were changed with each sample collection <br /> ' A chain of custody document, listing all samples collected, accompanied the samples from <br /> field to laboratory, thereby providing a means to track their movement and insure their <br /> integrity <br /> All water purged from each monitoring well and not used as a sample was placed in a <br /> ' properly labeled 55 gallon DOT approved container and stored on site until its proper <br /> disposition can be arranged <br /> ' Groundwater monitoring field logs are included in Appendix C <br /> 1.3 Laboratory Analyses <br /> The groundwater samples collected on December 18, 2002, were delivered to Sherwood <br /> ' Lab (Department of Health Services Certification No 1400), of Hilmar, California, for <br /> analysis <br /> lI <br /> Sherwood analyzed the sevetnmonttoring well groundwater samples for <br /> • Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX)by EPA method 8020 <br /> • Total Petroleum Hydrocarbons as Gasoline (TPH-G) by EPA method 5030/8015(M) <br /> ' • TEPH- Diesel and Motor Oil by EPA method 3500/8100(M) <br /> The detection limas for the above analyses are listed to Table of Appendix A while the <br /> laboratory analytical results are presented to Appendix B <br /> 1 <br />