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affected by petroleum hydrocarbons is estimated to be limited to an area of approximately 160 feet in diameter GROUNDWATER MONITORING ACTIVITIES ' On November 25, 2002, WGR Southwest, Inc 's (WGR's) John Terayskis and Sandra Goodman sounded and sampled the Port's former UST Site No 3 monitoring wells MW3-1 through MW3-3 Prior to initiating sampling activities, depth-to-groundwater measurements were made in each well and recorded on the well purging and sampling form (Appendix A) Before purging at each well, a bailer sample of groundwater was collected from each well, visually checked for free product, and a portion transferred to a beaker Field parameter measurements consisting of dissolved oxygen (DO) and oxygen reduction potential (ORP) were measured in the beaker and recorded on the well purging and sampling form DO and ORP measurements have been added to the list of field parameters starting this quarter to provide a indication of biodegradation of PHCs in groundwater DO measurements are typically collected in both PHC-affected groundwater and unaffected ' groundwater Microbes use oxygen as an electron acceptor in aerobic respiration processes Lower DO concentrations in affected groundwater compared to adjacent areas indicate aerobic biodegradation activities ORP of groundwater is a measure of electron activity ORP values typically are positive under oxidizing conditions (losing electrons) and negative under reducing conditions (gaining electrons) Anaerobic biodegradation generally creates a reducing condition in the vicinity of the biologic activity After the bailer sample was collected, each well was then purged of a total of about 100 gallons of water with a vacuum truck and dedicated stinger After the first 50 gallons were purged from each well, field parameters consisting of temperature, pH, and conductivity were measured and recorded on the well purging and sampling form Field parameters were collected again after the final 50 ' gallons were purged The 100 gallons purged represented more than 3 casing volumes of groundwater from each well A total of 300 gallons of purged water collected from the 3 wells was taken to Seaport Environmental under a Non-Hazardous Waste Transport Form by American Valley Waste Oil, Inc A copy of the signed bill of lading is included in Appendix C After purging, the wells were allowed to recharge to at least 80% of their respective static water levels prior to sample collection The samples were recovered using clean, disposable bailers, and were then transferred into 40-milliliter VOA vials All samples were labeled,placed in an ice chest, chilled with ice to 4° C, and transported to Precision Enviro-tech Analytical Laboratory(an ELAP- certified laboratory in Stockton, California) for analysis using appropriate chain-of-custody ' procedures The results of all current and previous groundwater levels are summarized in Table 1 Depth to ' groundwater in wells MW 3-1 and MW 3-2 was 12 70 feet and 12 62 feet, respectively An apparent problem occurred with the water level sounder while measuring water depth in MW 3-3 Because the water level measurement :n MW 3-3 is suspect, groundwater gradient and groundwater ' ust 53te3 qtr 13 doc 4 1