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I IGroundwater monitoring and sampling were conducted by Ground Zero personnel on November 10, 1995 The depth to groundwater was measured in each well and subtracted from the wellhead elevation to determine groundwater elevation Groundwater elevations are included Iin Table 1 Monitoring logs are included in Attachment C Groundwater flow was generally southwesterly with an hydraulic gradient of approximately 0 0017 feet per foot A potentiometric surface map generated using the November 10, 1995 monitoring data is shown on Figure 3 Groundwater samples were collected from wells MWI through MW3 on November 10, 1995, after purging a minimum of three well casing volumes and stabilization of physical parameters (pH, electrical conductivity, temperature) Purge water was stored on site in 55 gallon Icontainers pending laboratory analysis Field purge logs are included in Attachment C At the request of PHS/EHD, confirmation groundwater monitoring and sampling were performed ' on December 12, 1995 Groundwater elevations are included in Table I Field monitoring and purge logs are included in Attachment C Groundwater flow was generally south-southwesterly with an hydraulic gradient of approximately 0 0009 feet per foot A potentiometric surface map generated using the December 12, 1995 monitoring data is shown on Figure 4 LABORATORY ANALYSES ISelected soil samples from the borings were analyzed by Sequoia Analytical Laboratory for TPHg using EPA Method 8015, and BTEX using EPA Method 8020 In addition, selected soil samples collected from the borings were analyzed for physical parameters including vertical permeability, effective porosity, moisture content, bulk density, particle size distribution, and I hydraulic conductivity Selected soil samples collected from the borings were also analyzed for chemical/biological parameters including total organic carbon (TOC), heterotrophic plate count, phosphorus, potassium, and nitrogen (PKN) Groundwater samples collected from the wells were delivered under chain of custody to Argon Laboratory and analyzed for TPHg using EPA modified Method 8015 and BTEX using EPA Method 8020 LABORATORY RESULTS TPHg and BTEX were not detected in soil samples collected from borings SBI through SB3 Soil analytical results are summarized in Table 2 TPHg and BTEX were not detected in groundwater samples collected from wells MW I through MW3 during the initial sampling in November 1995 nor during the confirmation sampling in December 1995 Analytical results of groundwater samples are summarized in Table 3 Attachment D contains laboratory reports and chain of custody documentation for soil and groundwater sampling I i groundzelnormaclsumrepor 95 4 I