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Following retrieval of the sampler, the first (lowest) sample tube will be removed from the sampler, the ends covered with aluminum foil or Teflon film, and capped with PVC end caps. Soil in the next sample tube (where available) should be used to describe the lithology and measure volatile organic compound (VOC) concentrations. Approximately half of the sample from the sample tube will be removed and placed in a resealable plastic bag. The plastic bag will be set aside to allow VOCs, if present, to accumulate in the headspace above the sampled soil. The headspace will then be sampled using a portable photo -ionization detector (PID). The PID probe should be inserted through a hole made in the plastic bag and the highest measurement encountered recorded on the boring log. • Soil and wastewater generated during the field activities will be contained in 55 -gallon United Nations approved drums. Well Construction Procedures • The monitoring wells will be constructed of flush jointed, threaded, 2 -inch I.D., Schedule 40 polyvinyl chloride (PVC) casing. The well casing will be delivered to the site in factory plastic wrap. The casing will have rubber or Teflon O-ring gaskets at the joints. • The slotted interval will consist of 0.020 -inch machined slots. The filter pack should consist of #3 Monterey Sand. The slot size and filter pack has been selected with the intent to minimize the amount of native lithologic and filter pack material entering the monitoring well. • A bottom screw cap will be placed on the bottom of the casing. A 15 -foot length of slotted casing in the shallow well and a 5 -foot length of slotted casing in the deep well will be joined to the bottom screw cap. The screened interval in the shallow well should be set so that no more than 10 feet or no less than 7 feet of well screen is below the current groundwater elevation. Blank casing will be used to construct the remainder of the well. During placement of the filter pack, the well will be suspended in the augers. The augers will be lifted 2 to 4 feet and the sand filter pack poured into the annulus. The augers will then slowly be lifted with sand filter pack placed "continuously" until the sand is approximately 2 to 3 -feet above the top of the screen. An approximately 2 to 3 foot thick zone of bentonite will be placed above the sand filter pack. IT CORPORATION SAC:\\\SACRFP 1 \COMMON\sacDP\2002\PRJ\PJ8\880\8800391 A.2ac. doc (01040000) A-2