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0019 '3 Herding Lawson Associates Appendix B All soil samples will be retained in brass tubes and the ends will be sealed with aluminum foil, plastic caps, and tape. samples will be stored in a cooled ice chest until delivery to a state-certified laboratory for testing. The sampling equipment will The cleaned between samples in a so- lution of Alconox and water and then rinsed with deionized water. The augers will be steam-cleaned between borings. Soil cuttings from the borings will be stored in Department of Transportation (DOT) certified drums. Chemical testing on samples from the borings will determine appropriate dis- posal methods for the soil. We will also collect a"grab-wa- ter sample from each boring with a stainless steel bailer. The water from the bailer will be poured into 40-milliliter f vials and stored in a cooled ice chest. Soil and ground-wa- ter samples will be analyzed from the borings as described Mi in Task 3. After evaluation of these data, along with the soil-gas data, we will locate between three and five moni- toring wC.: ls in an attempt to establish the "zero line.,, The monitoring wells will consist. of" 4-inch-diameter PVC casing with flush-mounted joints. The wells will be con- structed with 3 to 5 feet of screened section (0.02 inch i perforations) and 3 to 5 feet of solid PVC well casing (4- inch-diameter Schedule 40 PVC) . The bottom of the PVC cas- ing will be ca ; pped. The annular area between the casing and boring will be backfilled with No 3 Monterey sand or equiv- alent to at least 2 feet .above the screened section. A 6 to 32-inch layer of bentonite will be placed on top of the sand, and the remainder will be backfilled with a ce- ment/bentonite seal. The wells will be housed in alocking, traffic resistant box. A licensed surveyor will establish the surface elevation for each well. After the cement/bentonite grout has set for at least 32 hours, each well will be developed by bailing until the ground water is visually clear and free of sediment. During....- _ ......, development we we will monitor the turbidity, t- emperature, PH, and conductivity. Normally 3 to 5 well volumes are re- quired for development. Soil and water will be stored in 4 55-gallon drums and will become the property of 7-Eleven (the cost of their disposal is not included in this pro pogal) . Approximately 24 hours after well development, we Will accurately measure the depth to water in each well and r check for the presence of free product. Water samples will then be collected. Existing wells will also be purged and sampled at this time.