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er Project No S8080-06-03 September 6, 1995 Page 2 Well Purging and Sampling Approximately three well casing volumes of groundwater (7 5 to 9 gallons) were extracted from ' each monitoring well on June 30, 1995 utilizing a 2-inch diameter Grundfos submersible pump During the well purging activities, the groundwater was monitored for pH, electrical conductivity and temperature Approximately three well casing volumes of groundwater were extracted from t each monitoring well again on July 24, 1995 The re-sampling performed on July 24, 1995 was necessary due to the failure of the analytical laboratory (Sequoia Analytical)to analyze the samples within the allowable holding time for Methyl Tert-Butyl Ether(MTBE) Well sampling data sheets ' are presented in Appendix A Purged groundwater was pumped into DOT 17-H 55-gallon drums which were labeled and stored onsite pending receipt of laboratory analysis and subsequent disposal following regulatory protocols ' Following well purging on June 30, 1995, groundwater samples were collected from each well and decanted into one 1-liter amber sample,lar and five 40-m1 volatile organic analyses (VOA) vials equipped with teflon septums Following well purging on July 24, 1995, a groundwater sample was collected from each well and decanted into three 40-m1 VOA vials On each date the samples were sealed, labeled and placed to an ice chest containing blue ice The samples were transported to Sequoia Analytical using standard chain-of-custody protocol FINDINGS AND DISCUSSION ' Groundwater Elevations and Gradient A review of the last reported groundwater level measurements performed in November 1994, indicates that groundwater levels have risen approximately 3 to 3 5 feet in the last seven months The direction of groundwater flow beneath the site on June 30, 1995 ranged from south-southeast to south-southwest with a gradient that ranged from 0 003 to 0 004 feet/foot ' Laboratory Analysis ' The groundwater samples collected on June 30, 1995 were delivered to Sequoia Analytical, a California certified analytical laboratory, for the analyses of total petroleum hydrocarbons as gasoline and diesel(TPHg and TPHd) following EPA Test Method 8015 modified, benzene,toluene, ' ethylbenzene and total xylenes (BTEX) following EPA Test Method 8020, MTBE following EPA Test Method 8020 and halogenated volatile organics following EPA Test Method 601 The groundwater samples collected on July 24, 1995 were delivered to Sequoia Analytical for the ' analysis of MTBE following EPA Test Method 8020 The laboratory reports and chain of custody documentation for both the June 30th and July 24th sampling events are presented in Appendix B A copy of the original MTBE analytical report for which the holding time was exceeded is also ' included in Appendix B