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Mr. Jim Woodard July 20, 1994 Page 2 (bgs). Soil boring MW-1 was continuously cored for lithologic description from 50-feet b to 100-feet bas. Cores were not collected from Soil Borings MW-2 and MW-3. During drilling, the soil cuttings were monitored, at 10-foot intervals, for the presence of volatile organic compounds (VOCs) using a field photoionization detector (PID). Soil cuttings were collected, placed in a plastic bag, and allowed to stand for approximately 5 minutes. The air inside the bag was then tested using the PID. Field evidence did not identify the presence of petroleum hydrocarbon compounds in the soil cuttings; therefore, soil samples for laboratory analysis were not collected from the boreholes. The location of the three monitoring wells is illustrated on Figure 1. Borehole logs, including the results of the PID monitoring are included as Attachment A. Groundwater Monitoring Well Installation Prior to constructing the three wells, each of the three boreholes was reamed using 101/4- inch-diameter hollow-stem augers to approximately 100 bgs. The three groundwater monitoring wells were each constructed using 50-feet of 0.020-inch slatted, 4-inch- diameter, schedule 40, polyvinyl chloride casing (PVC) and 53-feet of blank, 4-inch- diameter, schedule 40, PVC. The annulus surrounding the casing was filled with Lonestar ti.. #2/12 graded sand (or equivalent) to approximately 3 feet above the height of the slotted casing. Approximately 4 feet of bentonite chips were placed on top of the sandpack and hydrated using tap water. The wells were sealed to grade surface using neat cement containing approximately 5-percent bentonite powder. The wells were completed above grade by surrounding the protruding PVC casing with an S-inch diameter steel casing with a locking lid. The steel casings were set in a 2-foot by 2-foot concrete base. The top of the PVC casing and the top of the cement base were surveyed for elevation, relative to mean sea level, on May 9, 1994, by Tom Morrow, Inc., a State of California licensed surveyor. Well completion details are included in the borehole Iogs in Attachment A. Results of the well survey are summarized in Table I and presented in Attachment B. Groundwater Monitoring Well Development and Sampling Prior to developing the three wells, static water levels were collected from each well. The groundwater monitoring wells were developed using a submersible pump. Groundwater was extracted from monitoring wells MW-1 and MW-2 on May 12, 1994. The extracted groundwater water was routinely monitored for temperature, pH,specific conductance, and Use or disclosure of data contained on this sheet is subject to the restriction specified at the beginning of this document. 1422\RF PORTMQTR.R PT