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S 4 , V 20 March 1996 ' AGE-NC Project No 95-0139 Page 3 of 6 3.0. PROCEDURES ` ' 3 1 MONITORING WELL PURGE PROCEDURES ; On 10 January 1996, a Solmst water level meter was used to measure the depth to water in each well r ' 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 ground water measurements, a submersible pump was used to remove standing water from each well Approximately 5 gallons (minimum of three well volumes) of water were removed ' from each well to stabilize temperature, pH and conductivity Ground water parameters were measured at one-gallon intervals using an ICM water analyzer All purging equipment was decontaminated in an Alconox solution and rinsed twice after each well was purged The purged ' water was stored in 55-gallon drums on-site Stabilization data and field logs are included in Appendix A 32 COLLECTION OF GROUND WATER SAMPLES Water samples were collected from each well using disposable plastic bailers The samples were transferred into 40-m1 EPA vials containing hydrochloric acid as a preservative and l-liter amber bottles After collection, the samples were placed in a chilled container and transported under chain- of-custody to Western Environmental Science & Technology (WEST) in Davis, California Each water sample was analyzed for TPH-g and TPH-d and volatile organics (benzene, toluene, ethyl benzene and total xylenes, BTE&X) in accordance with EPA methods 5030i8015m and 602, respectively � 1 �r 3 3 COLLECTION OF GEOPROBE SOIL AND WATER SAMPLES t Five probings were advanced on 22 January 71996 using AGEs Geo robe 5400 probing unitequipped with a 2 15-inch diameter sampling assembly and 1 125-inch diameter probe rods The location of the five probings is as follows (see Figure 2) probing B5 north of MW-1, probing B6 west of the former UST excavation, probing B7 east of the current pump island, north of the current USTs, probing B8 east of the current pump island and south of the current USTs, and probing B9 in the driveway of the property immediately west of the site Probmgs B5 and B6 were advanced to 15 5 feet below surface grade(bsg), probings B7 arid B8 were advanced to 14 5 feet bsg and probing B9 was advanced to 13 5 feet bsg, the elevation of probing B-9 is approximately 1 5 feet below surface grade of the site for the other probings 1 Sort samples were collected from each probing at 2-foot intervals beginning at a depth of 9 feet in