Laserfiche WebLink
9%TCv <br /> • A s s O C I A T E S I N C <br /> 2.0 METHODS AND PROCEDURES <br /> ' To evaluate if groundwater has been impacted by petroleum hydrocarbons present in soil beneath <br /> the site, one soil boring was advanced through the location of the former 3,000-gallon UST and <br /> completed as a groundwater monitoring well All field activities were performed in accordance <br /> ' with ATC's Workplan for Additional Subsurface Investigation at Diesel Performance, 2804 East <br /> Fremont Street, Stockton, Callforma, dated August 24, 1998 This workplan was approved by <br /> PHS/EHD on September 2, 1998 <br /> ' 2.1 Soil Boring Advancement and Samph!Lg <br /> ' Drilling was conducted by V & W Drilling (State C57 license no 720904) utilizing a hollow stem <br /> auger drill ng Soil boring NMI was advanced and completed as a groundwater monitoring well <br /> A field geologist logged drill cuttings and soil samples utilizing the Unified Soil Classification <br /> System Descriptions of soil types encountered and sample collection intervals are included on <br /> the boring/well log contained in Appendix A <br /> ' The cored soil samples were collected at five-foot intervals using a 2-inch diameter split-spoon <br /> sampler containing three brass tubes The cored samples and drill cuttings were characterized for <br /> soil type, moisture content, and visual evidence of petroleum hydrocarbons A flame ionization <br /> detection meter (FID) was used as a field screening device for the detection of petroleum <br /> hydrocarbon vapors in drill cuttings and cored samples Drill cuttings were temporarily stored on <br /> ' site in 55-gallon DOT approved steel drums <br /> 2.2 Soil Sample Analysis <br /> ' Soil samples were placed on ice, and transported under chain-of-custody to Sequoia Analytical <br /> (FLAP #1210) of Redwood City, California for analysis Soil samples were selected based on a <br /> ' verbal discussion with Ms Lori Duncan of PHSIEHD All soil samples were analyzed for total <br /> petroleum hydrocarbons as gasoline (TPHg), total petroleum hydrocarbons as diesel (TPHd), <br /> total petroleum hydrocarbons as kerosene (TPHk), benzene, toluene, ethylbenzene, and xylenes <br /> ' (BTEX) utilizing EPA 8015 and 8020 methodologies, and oxygenate fuel additives utilizing EPA <br /> 8260 methodology The analytical results for soil samples are summarized in Table 1 Laboratory <br /> data sheets and chain-of-custody documentation are included in Appendix C <br /> ' Groundwater Monitorin Well Construction <br /> 2�3 _ $ -— <br /> ' Soil boring MW 1 was subsequently completed as a groundwater monitoring well to assess if _ <br /> groundwater beneath the site had been impacted The well was constructed with 2-inch PVC <br /> casing The screened interval of the well was positioned from approximately 5 feet above to 15 <br /> ' feet below the encountered water table to allow for seasonal water level fluctuations The screen <br /> slot size is 0 010-inch Well construction details are depicted on the well log contained in <br /> Appendix A <br /> w 1625771reports%sumu d" 2 <br />