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08 July 1999 AGE-NC Project No. 95-0130 Page 7 of 10 4.0. FIELD PROCEDURES All field procedures will be overseen by an AGE representative under the supervision of a California Registered Geologist. Procedures for the monitoring well installation, well development, ground water sampling, soil sampling,equipment decontamination and sample shipment are outlined below. 4.1. CPT DRILLING CPT soil borings will be advanced to depths of 100 feet bsg utilizing a 25-ton truck-mounted CPT drill rig equipped with 2-inch diameter hollow-stem rods. The first soil boring will utilize a hydraulic ram to advance a cone penetrometer to the desired depth. Soil parameters such as cone bearing, sleeve friction, friction ration and pore water pressure will be measured as the cone penetrometer is advanced. Rinseate generated during drilling activities will be containerized in properly labeled D.O.T. 55-gallon drums, and stored on-site in an area lacking public access. Disposal alternatives will be evaluated at a later date based on laboratory results of rinseate. A second soil boring will be located adjacent the first CPT boring for soil sample collection. Based on CPT findings,discrete soil samples will be collected beginning at a depth of 20 feet bsg at 10-foot intervals or in areas of lithologic variation. Soil samples will be collected utilizing a 2-inch diameter piston soil sampling assembly loaded with pre-cleaned brass sleeves. Upon soil sample retrieval, a brass sleeve will be removed from the sampler. The ends of the brass sleeve will be immediately covered with Teflon or aluminum sheets, sealed with plastic end caps, secured with tape and immediately placed in a chilled container for transportation to a DHS state-certified laboratory. Each sample sleeve will be labeled with the location,boring designation, depth, time, date and sampler's initials. During soil sampling activities, sample duplicates will be monitored for the presence of organic vapor using a photo-ionization detector(PID: Thermo Environmental 580A, 10.0 eV, calibrated to isobutylene)and recorded on boring logs. Soil sample duplicates will be described using the Unified Soil Classification System (USCS) and recorded on the boring logs. Proposed soil boring locations are illustrated on Figure 2. Following borehole advancement,portland cement(grout mix)will be utilized to backfill each borehole utilizing a tremie pipe. The PHS-EHD will be given the opportunity to inspect the grout mix prior to backfilling activities. 4.2. MONITORING WELL DRILLING Ground water monitoring wells will be advanced utilizing a truck-mounted,hollow stem drill rig and Advanced GeoEnvironmental,Inc.