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r groundwater monitoring data (March 1992) determined groundwater flow direction to the south. A detailed discussion of the initial subsurface investigation can be found in RESNA's 'Interim Problem Assessment Report, Soil and Groundwater Contamination, ' dated June 8, 1992 In July 1994, a RESNA field geologist observed the drilling of four additional groundwater monitoring wells (MW4, MW5, MW6, and MW7) at the site to further characterize subsurface conditions. Groundwater samples collected from these additional wells contained no detectable petroleum hydrocarbons. A detailed discussion of the Phase 2 Subsurface Investigation can be found in RESNA's "Summary Report, July 1994 Investigation, ' dated August 26, 1994. In a letter received from the PHS/EHO dated March 1995, permission was given to sample wells MW3 and MW5 and wells MW4, MW6 and MW7 on an alternating semi-annual basis Wells MW1 and MW2 were to be sampled every quarter, conditions permitting GROUNDWATER- MPL Smith Environmental personnel performed groundwater monitoring and sampling on January 51 1996. Due to bad weather, the fourth quarter 1995 quarterly monitoring and sampling was • delayed until January 5, 1996. Field work included measuring the depth-to-water in wells MW 1, MW2, MW3, MW4, MW5, MW6, and MW7; using an electronic water/product interface probe to determine if free product was present; purging and sampling wells MW1, MW3, and MW5, and subjectively evaluating collected water samples for the presence of petroleum hydrocarbon constituents. j Static groundwater elevations were measured in each monitoring well on January 5, 1996 Groundwater exists at approximately 12 to 13 feet below grade A groundwater gradient map is presented in Figure 2 It depicts a southerly and easterly groundwater gradient at an average of 0.003 ft/ft or approximately 16 feet/mile. Fluid level measurements indicated groundwater flow direction beneath the site during the fourth quarter was different than the last monitoring event Groundwater flow direction beneath the site may be subject to seasonal fluctuations Groundwater monitoring data are summarized in Table 1. On January 5, 1996, groundwater samples were collected from monitoring wells MW 1, MW3, and MW5. Samples were collected after stabilization of pH, electrical conductivity (EC), and temperature All wells monitored were purged and sampled according to Smith Environmental's Quality Assurance/Quality Control Plan on file with the PHS/EHD. A minimum of four casing volumes of water were removed from each sampled well Purge water was contained in labeled DOT approved 55 gallon drums and stored on site pending laboratory analysis and proper disposal. A dedicated disposable bailer was used to collect each ..'gnAXn.-,QR IM WC • SMTH