Laserfiche WebLink
GROUND ZERO ANALYSIS, INC. <br /> 1714 Man Street <br /> Escalon,California 95320-1927 <br /> Telephone (209)838-9888 <br /> Facsunde (209)838-9883 <br /> December 16, 2004 <br /> Mr Michael Infuma <br /> San Joaquin County <br /> Environmental Health Department <br /> 304 E Weber Ave , Third Floor <br /> Stockton, CA 95202 <br /> Subject Fourth Quarter 2004 Groundwater Monitoring and Sampling Report <br /> Valley Pacific Petroleum Services, Inc (Woolsey Oil, Inc) Cardlock Facility <br /> 1501 W Charter Way, Stockton, CA (Site Code 508175) <br /> I <br /> Dear Mr Infurna <br /> This letter report presents the results of the fourth quarter 2004 groundwater monitoring and <br /> • sampling activities at the subject site (Figure 1) <br /> Site Activities <br /> Activities at the site included monitoring water level elevations, purging and sampling groundwater <br /> from all site wells Groundwater samples were analyzed for total petroleum hydrocarbons as <br /> gasoline (TPHg), total petroleum hydrocarbons as diesel (TPHd), benzene, toluene, ethylbenzene, <br /> total xylenes (BTEX), and gasoline oxygenate additives In addition, all samples collected were <br /> analyzed for CAM 17 metals, hexavalent chromium (Cr 6), selected mineral cations and anions, <br /> dissolved oxygen (DO), total suspended solids (TSS) and total dissolved solids (TDS) These <br /> additional analyses where done in order to evaluate whether the injection of an oxidizer, such as <br /> hydrogen peroxide, might result in the liberation or creation of objectionable dissolved chemical <br /> species, such as hexavalent chromium <br /> Fieldwork <br /> On November 23, 2004, monitoring wells MW1 through MW5 were monitored and sampled <br /> Groundwater elevations were calculated by measuring the depth to groundwater in each well and <br /> subtracting from the respective wellhead elevation Groundwater elevations at the site fell an <br /> average of 0 20 feet since last monitored on August 6, 2004 The average hydraulic gradient across <br /> the site was approximately 0 004-0 005 ft/ft Groundwater flow was toward the north, but with <br /> components of northwest and northeast flow A potentiometric surface map created from the <br /> • November 23, 2004 monitoring data is depicted on Figure 2 Groundwater elevation data are <br /> summarized in Table 1 Monitoring data sheets are included in Attachment A <br /> G 1GROUNi)ZE1W00LSEY CHTIQMR1200414QM2004 doe <br />