Laserfiche WebLink
A Boring, identified as B-T, was placed by JPCA on June 24, 1994 , <br /> approximately in the center of the former UST and extended to the <br /> saturated zone, approximately 35 feet. Soil samples were collected <br />' at each five feet commencing at 11 feet. A grab water sample was <br /> collected. Figure 2 presents the location of the former UST area <br /> and B-T. <br />' The soil and groundwater samples were analyzed for Total Petroleum <br /> Hydrocarbons as Gasoline (TPHG) and Benzene, Toluene, Ethylbenzene <br />' and Xylene (BTEX) using Modified EPA Methods 8015/8020. <br /> Based on the results of the analysis from the initial boring, San <br /> Joaquin County Environmental Health Division (SJCEHD) required an <br /> additional subsurface investigation to better define the extent of <br /> the soil and possible groundwater contamination. JPCA addressed <br /> the county requirements and prepared a workplan which was accepted <br />' by SJCEHD. <br /> A permit was requested and received from SJCEHD prior to drilling <br /> the three borings and three monitoring wells. In October 1994, the <br />' borings and wells were completed with soil and groundwater samples <br /> collected for analysis. <br /> Soil samples collected from a depth of 20 feet to groundwater at <br /> approximately 30 feet were analyzed and contained gasoline and <br /> gasoline constituents. Groundwater samples contained actionable <br /> levels of gasoline and gasoline constituents. <br /> FIELD WORK <br /> John P. Cummings of JPCA met with Harlin Knoll, Senior REHS, San <br /> I Joaquin County Environmental Health Division, on site during the <br /> morning of April 21, 1997 . <br /> IGRADIENT DETERMINATION <br /> Prior to purging and sampling, on April 21, 1997, the depth to <br /> groundwater was measured by an electronic probe in the three <br /> Monitoring Wells on site, see Figure 2 for locations of the wells <br /> on site. The water depth was measured from a mark located on the <br /> top of the casings. The groundwater gradient data are presented in <br /> Table I. The calculated gradient is S 72 W or 2880 at 0. 02 ft/ft. <br /> The groundwater gradient is depicted in Figure 2 . Field notes are <br /> contained in Appendix A. <br /> i2 <br /> ,f <br />