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Location and installation of Windy Gulch wells, drive point piezometers, and weirs 5 <br />2.2.1 DP-1 <br />Drive point piezometer DP-1 was installed upstream of the 9700 dump, just off the northern end of <br />the road, at the base of the talus material present on both sides of Windy Gulch (Plan 2.1). Upon <br />digging a test pit, the thick talus material appeared unsuitable for continuing with manual <br />installation of the drive point. Subsequently, a backhoe was used to deepen the excavation. The <br />maximum attainable depth of the talus excavation was about 12 ft. At this depth, either competent <br />bedrock or a very large boulder was encountered, which prevented further deepening (within <br />reason) of the excavation. The drive point was set to a depth of 12 ft. No flow channel is visible <br />in the talus in this section of Windy Gulch. The drive point was placed in the center of the gulch. <br />Water was observed trickling into the excavation in one discrete area at a depth of about 10 ft. <br />The water flowed to the bottom of the excavation and disappeared into the underlying coarse <br />material. In an attempt to create a saturated condition, the excavation was partially backfilled with <br />fine native material present east of DP-1 (above the 9700 dump). Higher flows in Windy Gulch <br />provide adequate water in DP-1 to allow sampling. <br />2.2.2 DP-2 <br />DP-2 is located about 150 ft downstream of the 9700 dump in a relatively flat lying portion of <br />Windy Gulch (Plan 2.1 ). A 4.5 ft deep test trench was dug at this location to remove any coarse <br />material present below the selected drive point location. The point was driven from the trench <br />bottom to a maximum depth of about 7.5 ft. Although DP-2 has been monitored regularly, no <br />water has ever been detected in the installation and no samples have been collected. The ground <br />surface at the drive point is approximately 5 ft above the adjacent stream channel which exhibits <br />intermittent flow in this reach. <br />2.2.3 OP-3 <br />The location selected for this drive point piezometer was about 500 ft north of the 9360 Dump, just <br />west of the 9700 Weir (Plan 2.1). The point was driven from the natural ground surface to a total <br />depth of about 5 ft. The water depth in the drive point is about 2 ft below ground surface. <br />Following installation, approximately 7 gallons were bailed from the drive point piezometer. The <br />ground surface at the drive point is approximately 1.5 ft above the adjacent channel. <br />2.2.4 DP-4 <br />DPI is located below the 9360 Dump in a gently sloping area (Plan 2.1). A pilot hole was dug to <br />a depth of about 2.5 ft and the point driven to a total depth of about 7.5 ft. The water depth in the <br />drive point was observed to be about 3.7 ft below ground surface. Prior to sampling, about 35 <br />gallons were bailed from the drive point. However the suspended solids content has remained <br />relatively high despite significant development through bailing. <br />DP-4 was replaced with a new drive point piezometer (DP~R) on June 6, 1999, about 5 ft <br />downstream from the original location. This replacement was completed because of the relatively <br />high suspended solids content noted in samples which suggested that the well screen may have <br />been damaged during installation. DP~R was installed using 2-inch stainless steel drive pipe <br />