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r]Rase H Environmental Site Assessment Heritage Square Page 4 diameter cutting shoe The hand auger borings were manually using a 3- inch diameter bucket. The cutting shoe, hand auger bucket, and associated push rods were thoroughly cleaned before each use with laboratory-grade, non..phosphate detergent and de-ionized water and double-rinsed with de-ionized water. Upon completion of the drilling and sampling, the direct pushboreholes were backfilled with grout and the hand auger boreholes were backfilled with clean aggregate base and capped with concrete. 4.3.1 Soil Sampling Soil samples were collected from each Geoprobe° boring from approximately two feet below the bottom of the respective nearby UST and at five-foot intervals thereafter to a depth of 10 feet below the deepest evidence of hydrocarbon contamination or 30 feet bgs, whichever was greater. A minimum of two soil samples from each boring were retained for laboratory analyses. Borings B-1, B-2, and B-4 were advanced to approximate depths of 20 feet bgs, and borings B-6 through B-8 were advanced to approximate depths of 16 feet bgs. As field observations indicated that contamination was present in boring B-3 east of TK 1, samples were collected at less than five-foot intervals through the impacted zone, a total of seven samples from the boring were retained for analyses, and the boring was advanced to a depth of 36 feet bgs. Obvious indicators of contamination were present near T.K2 in boring B-5 as well, and a total of three samples from this boring were retained for analyses and the boring was advanced to a depth of 40 feet bgs. Groundwater samples were also collected from each of these impacted borings. Sample depths for borings B-1 through B-8 are indicated on the geologic logs in Appendix B.Borings C- 1 through C-4 were advanced to approximately two feet beneath the underground piping. Soil samples were collected from this depth for each of these borings. Soil samples were collected from the Geoprobe" borings using a 2-inch outside diameter, 4-foot long core barrel, fitted with a clean, single use, acetate liner. Soil samples were collected from the hand auger borings by driving a sampling sleeve into the soil with a slide hammer. The soil sampling equipment was cleaned prior to boring the next hole and the cutting shoe and sampling sleeve were cleaned prior to collecting each sample by washing them in a solution of laboratory-grade, non-phosphate detergent and deionized water, and double-rinsing with de-ionized water. During the soil sampling, the Geoprobe"' core barrel was driven continuously in four-foot intervals to between 16 feet and 40 feet bgs. After the core barrel was driven four feet, the core barrel was withdrawn and the sample was removed. The sample liner was extracted from the core barrel and used for geologic logging and field observations. A new unused acetate liner was placed in the core barrel and the process was repeated. All soil samples were logged according to the Unified Soil Classification System (USCS). Geologic logs were prepared containing field observations including soil type, estimated moisture content, photo ionization detector (PID) measurements, and the presence of staining or odor. The geologic logs are included in Appendix B. Each soil sample selected for potential laboratory analyses was cut from the liner. The soil samples were retained, undisturbed, in the liners. The liners were sealed at the ends with Teflon sheeting, capped, and labeled. The samples were stored in a cooler chilled with Blue Ices and delivered under chain-of-custody procedures to Excelchem .Environmental Labs (Excelchem) of Roseville, California. The samples were analyzed using U.S. EPA and California approved methods. L� 4.3.2 Groundwater Sampling Groundwater samples were collected from two of the Geoprobe° borings, B-3 and B-5. The borings were completed to termination and then new PVC casing and riser were placed in the open boreholes. Groundwater flowed hydrostatically from the formation into the inlet screen. A groundwater sample was retrieved from within the screen with a length of clean,318-inch diameter poly tubing with a check valve at the bottom. The tubing was pumped up and down by hand to draw groundwater up the tubing. The is CONDOR