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' The monitoring well was constructed with fifteen feet of four-inch schedule 40 PVC well screen ' with 0.01-inch slots, and 105 feet of blank four-inch schedule 40 PVC well casing. The screened interval was surrounded by a sand pack of Lonestar # 2/12 sand which extended three feet above the top of the screen (see attached boring log). During sand installation, the ' well was surged with a 4-inch bailer to assure proper placement of the sand. Above the sandpack, four feet of bentonite pellets were placed in the annular space to provide an annular seal. A 1-inch diameter PVC pipe was placed to the top of the bentonite seal at a depth of ' 95.5 ft bgs, and a 5% bentonite grout mixture was pumped into the annular space until the grout reached the ground surface. The displaced drilling mud was released into the large storm ' water containment pond (dry) adjacent to the drilling site. An 8-inch steel standpipe with a locking lid was welded to the inside of the conductor casing to cover the exposed portion of the top of the well. A 4-inch PVC slipcap was placed on top of the well to prevent any debris from entering the well. After completion of the groundwater monitoring well, it was developed by purging at least ten wet casing volumes from the well. Purging was performed with a 20-foot long, 10-gallon capacity bailer lowered into the well from a Smeal well development rig. Ph, temperature, and ' conductivity measurements were taken from the development water at various intervals during the development process (see table 1). The development water was pumped into a 550-gallon tstorage tank which was left on site pending analytical results. All drilling tools and sampling equipment were pre-cleaned at the driller's yard using a high- pressure hot water wash before use. 4.0 GROUNDWATER SAMPLING ' Groundwater samples were collected from the monitoring well using a disposable two-inch bailer. In order to reduce the loss of volatile constituents, samples for volatile organic compounds analysis were dispensed from the bailer using a disposable VOC sampler. A water sample was also collected from the 550-gallon development water storage tank. The two water samples were released into laboratory-supplied, sterile sample containers. The sample ' containers were labeled, placed in a cooler on ice, and transported under chain of custody documentation to Curtis and Tompkins laboratories, in Berkeley, California. 1 ' 14744003.013 3 TRC