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} -_ 06 February 2001 AGE-NC Project No. 95-0118 Page 4of7 2.2. GAUGING OF DEPTH TO GROUND WATER AND PURGING OF WELLS On 19 January 2001,the depths to ground water in the monitoring wells were measured relative to the top of the well casings using a Solinst water level meter. Subsequently, approximately six to i eight gallons of water(a minimum of three saturated-casing water volumes)were removed from each ground water monitoring well MW-1 through MW-6 using a submersible PVC pump. An ICM Model 52200 water analyzer was utilized to monitor temperature, pH and conductivity of purged water at regular purge-volume intervals. Purged ground water was containerized in 55-gallon drums and stored on-site. Stabilization data and field logs are included in Appendix C. -+ 2.3. COLLECTION AND ANALYSIS OF GROUND WATER SAMPLES Water samples were collected from the purged wells using new disposable plastic bailers. The collected samples were transferred into EPA-approved 40-m1 volatile organic analysis (VOA)vials containing 0.5 milliliters hydrochloric acid(18%)as preservative. The samples were labeled, logged r -'-' on a chain-of-custody form,placed in a chilled container and transported to MAI. Each sample was analyzed for TPH-g, BTEX, and nine fuel additives in accordance with EPA Methods listed in Section 2.1. 4.0. FINDINGS Extracted soil vapor samples were collected from the positive pressure blower for laboratory analysis during the three monitoring events over the last three months (quarter). The data collected was used to estimate the mass of hydrocarbons removed from the soil at the site. Ground water elevation, flow direction and gradient were determined from field data collected on 19 January 2001; the contaminant impact to ground water was assessed from the laboratory data derived from the ground water samples. _i 3.1. SOIL VAPOR EXTRACTION During the later portion of the operating period,the blower operated at an extraction flow rate of 60 sefm. An induced vacuum (negative pressure) as high as 14 inches of water was monitored in the piping between the blower and the extraction wells. 1 TPH-g was detected in the 27 November 2000, 21 December 2000 and 23 January 2001 samples Advanced GeoEnvironmental,Inc.