ARCHIVED REPORTS_XR0004438 - Laserfiche WebLink

Home Browse Search

Boyett Petroleum 419 Main Street, Manteca, California Quarterly Groundwater Sampling Report June, 2001 1 Narrative tOn June 4, 2001, GeoAnalytical Laboratories, Inc., conducted field measurements, well pumping and groundwater sampling on eight (8)groundwater monitoring wells located at this site(Figures 1 and 2). On June 15, 2001, GeoAnalytical sampled MW-9. ' Groundwater elevations were taken from nine 9 wells prior to pumping Table 1 & ( ) P p Pg ( Appendix B). Monitoring wells MW-1 through MW-9 were evacuated by means of a ' steam-cleaned, stainless steel bladder type pump. During the three (3) volume pump down of each well, samples were collected to measure field pH, electrical conductivity ' and temperature (Table 3 & Appendix B). Once stability was achieved, a minimum of three (3) well volumes were removed and samples were collected with a disposable bailer. The samples were then labeled and placed in an ice chest cooled with Ice®. lie The samples were then logged on a Chain of Custody (Appendix A) and transported to the State-certified laboratory, GeoAnalytical Laboratory Inc., in Modesto, California. ' The analysis requested for the nine (9) water samples was EPA method 8260B for BTX&E (Benzene, Toluene, Xylene, and Ethyl-Benzene), oxygenates, Ethylene Dibromide (EDB), and 1,2-Dichloroethane (1,2-DCA), and EPA method GCFID ' (5030/Luft) for gasoline. The analytes and concentrations detected are listed in Table 2 of this report. Groundwater Gradient ' The .water level measurements from eight (8) monitoring wells (MW-1 — MW-8) were used to construct a groundwater gradient map (Figure 3). MW-9 is a deep well, therefore ' it is not used in the gradient calculation. This quarter, the groundwater gradient trend is South 80° West with a downward slope of 0.0006 ft/ft. Historical groundwater gradient maps are provided for reference in Appendix C. 1 ' 1