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not converted to monitoring wells will be backfilled by pouring a cement slurry not exceeding 5% ibentonite through the auger. 3.3 Soil Sampling Soil samples will be collected to the first occurrence of groundwater and will be collected at 5-foot intervals Groundwater has been measured at approximately 21 to 25 feet below grade. Soil samples will be collected through the auger in three 6-inch long brass sleeves with a 2-inch diameter an a split-spoon sampler. The sampler is driven ahead of the auger by a 140 pound hammer with a 30-inch drop. The brass sleeves and sampler will be washed with an Alconox solution and rinsed with deomzed water prior to each use. One brass sleeve containing soil from each interval will be capped, sealed, labeled in accordance with EPA protocol, recorded on a chain of custody form, placed in a cooler at 4 degrees centigrade and transported to a California certified analytical laboratory for the specified analyses under proper chain of custody documentation. Another brass sleeve will be used for hthologic description. All field data regarding lithology, recovery and blow counts will be recorded on boring logs. 3.4 Field Screening of Soil Samples • One brass sleeve will be used for field screening of samples. The material from the top tube will be placed in a sample Jar filled to approximately 50 percent capacity, shaken and stored for a period of approximately 5 minutes. A standard headspace reading will be collected at this time using a Foxboro organic vapor analyzer (OVA) or equivalent field instrument and noted on the boring log. 3.5 Soil Analyses Soil samples will be analyzed by a California certified laboratory in accordance with State guidelines and EPA protocol The samples will be selectively analyzed for total petroleum hydrocarbons (TPIT) quantitated against gasoline standards and benzene, toluene, ethylbenzene and total xylenes (BTEX) and using EPA methods 8015M and 8020, respectively. I 3.6 Installation of Monitoring Wells Two groundwater monitoring wells will be constructed in soil borings as shown on Figure 2. The wells will consist of 4-inch, flush threaded, schedule 40 PVC slotted and blank casing. A threaded end cap will be placed at the bottom of the PVC which will then be set through the auger. The screened PVC casing will consist of 0.02 inch machine cut slots Number 2 sand will be poured down the auger whale removing approximately 2 feet of auger at a time. The filter pack will be placed 2 feet above the screened interval. Three feet of bentonite pellets will be poured 5023J2 4