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History Well 29.28 • • Drilling fluid consisted of clear water with a light polymer until the Dissolution Surface was encountered at 1365-ft bgs. • A suite of geophysical logs were completed following completion of coring. The core hole was completed as a Lower Aquifer monitoring well installation just above the Dissolution Surface as shown in the completion diagram.for Well 29-2. Below the monitoring well completion, the core hole was cement-grouted from TD (2133-ft bgs) to a depth of 1385 - ft bgs. The well completion was constructed with 2-inch Schedule 80, flush- threaded, O-ring sealed, PVC well casing and 2-inch Schedule 80, 0.02- inch slotted (20-slot) well screen to a depth of 1362-ft bgs. A 10-ft screen was placed at the base of the well completion interval from 1352- to 1362- ft bgs. • Sand pack (clean, #8) was placed from 1362- to 1342-ft bgs. • A bentonite sea! was placed at the top of the sand interval. The core hole was cement-grouted from the top of the sand pack using a 1-inch tremie pipe to assure complete grout placement. Finally, a steel, flush-threaded extension with a locking cap was added to the top of the surface casing resulting in a finished elevation approximately 2 ft above land surface. The core generated by drilling Well 29-2 was logged to provide stratigraphic, structural, and assay information. • The lithology, core recovery, and rock quality designation (RQD) were logged. In situ conductivity testing was conducted to estimate the hydraulic conductivity of the ore zone. The interval between 151- to 2016.8-ft bgs was geophysically logged after completion of drilling. The suite of fogs recorded include Natural Gamma, Spontaneous Potential (SP), Resistivity, and Temperature (SG). 1'~ Phase Well Development • A Grundfos pump was used to draw water out of the well from a depth of 500 ft. Approximately 1000 gallons of water were removed in early Feb 1999. • Attempts to bail water samples from the screened interval failed after the well was developed as a result of plugging from precipitation of bicarbonate in the casing. A sampling bailer used to attempt to collect a water sample returned with bicarbonate crystals inside. The precipitate completely blocked off access to the appropriate sampling interval. B Groove Recompletion • On July 20, 1999, the interval between 1030' -1040' and 1023' -1033' was perforated with 1 9/16° HSC, 4 spf, 6 gram charges. On July 23, 1999 a bridge plug was set beiween the dissolution and B . Groove at 1150'. The bridge plug was capped with 5' of cement and 25' of sand to 1120'.