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. 20 May 1996 AGE-NC Project No 95-0101 Page 3 of 4 3.0. PROCEDURES 3 1 MONITORING WELL PURGE PROCEDURES On 04ril 1996 a Sohnst water level meter was used to measure the depth to ground water in each well relative to the top of the casing The relative ground water elevations and hydraulic gradient were determined from these data (Table 1) After depth-to-water measurements, wells MW-2, MW-3 and MW-6 were purged using pre-cleaned PVC bailers Approximately 5 to 6 gallons (minimum of three well volumes) of water were removed from each well Temperature, pH and conductivity were measured at one-gallon intervals using an ICM water analyzer Stabilization data and field logs are included in Appendix A All purged water was stored in 55-gallon drums on-site In accordance with a 29 March 1996 conversation with Mr Harlin Knoll of the PHS-EHD, the sampling frequency of monitoring wells MW-1, MW-4 and MW-5 was reduced to semi-annual monitoring, and were not included for sampling this quarter 3 2 COLLECTION OF GROUND WATER SAMPLES Water samples were collected from each purged well using new disposable bailers Immediately upon retrieval, the samples were transferred into 40-m1 EPA vials containing hydrochloric acid as a preservative The samples were transported in a chilled container, under chain-of-custody, to McCampbeIl Analytical, Inc (MAI) and analyzed for TPH-g and BTE&X in accordance with EPA methods GCFID/5030 and 602, respectively 4.0. FINDINGS 4 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT The relative elevation of ground water in each well was calculated by subtracting the depth to water from the surveyed casing elevation (Table 1) All wells were surveyed relative to MW-3, which was assigned an arbitrary elevation of 100 feet The relative ground water elevation ranges from 28 40 feet in MW-6 to 29 32 feet in MW-4 Ground water has risen an average of 1 62 feet since the August 1995 monitoring event As with previous measurements, the ground water elevation in MW-5 was again anomalously low Since water is not extracted from this well, this anomaly could not be explained The ground water flow direction is generally southerly with a gradient of approximately 0 0058 ft/ft,