2010-03-10_PERMIT FILE - M2008012 (2)

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Geologic Log - supplement to GWS-31 for MH-48088 MMW1 Depth ft Type Grain Size Color Water 0-5 sandstone f-m It gray 5-30 sandstone f-m buff to ale red brown 30-40 sandstone f buff to ink brown 40-45 siltstone/shale silty shale gray 45-50 sandstone of-f gray 50-70 sandstone f buff to ink brown 70-80 sandstone, some shale f-m red brown 80-100 sandstone f-M gray 100-105 sandstone & shale of yellow brown 105-115 siltstone/shale silt & clay red brown to maroon 115-120 siltstone to sandstone of brown 120-140 sandstone f It gray top, red brown bottom 140-145 shale clay red brown 145-160 silty sandstone sil -vf ale ink brown 160-170 sandstone f -m red brown 170-180 mudstone silty dk red brown, blue green 180-200 mudstone to sandstone clay - of red brown 200-220 sandstone of-f-m tan to red brown 220-240 sandstone f-m gray to yellow brown 240-260 sandstone silt -vf __gray to yellow brown 260-280 sandstone silty-vf yellow brown - some thin variegated sh - blue ra , olive, red 280-300 sandstone of-f ale yellow brown Entrada Ss ? -290 300-315 silt and sandstone to mudstone? silt - f yellow brown to It gray 315-320 shale/mudstone clay-silt red 320-340 mudstone clay-silt red brown Comments: Although circulation was never lost during drilling (samples return was continuous), it was during completion, suggesting that one or more mines, drifts, or open fractures were penetrated by the borehole. No geophysical log was obtained (equipment malfunction). The borehole was backfilled with native materials to 310 feet, then PVC casing was set as described on the attached form GWS-31. Twenty-two 50-]b sacks of 10-20 sand filter pack were poured into annulus which subsequently had a measured level of 250 ft. Bentonite pellets were poured into the annulus and the depth remeasured at almost 300 ft, suggesting that the weighted tape had entered another hole or cavity. Repeated efforts to measure the depth of the sand and bentonite in the annulus resulted in sticking the tape and losing the weight. The monitoring hole was then sealed from 10 to 3 ft below ground surface with hydrated bentonite, and cement from 3 feet to the surface. A cement surface cap was constructed and a locking well head casing protector installed. Thus, the monitoring well was constructed with perforations and sand from 250 to 310 ft of depth, and perhaps more, as the tape was lost in an adjacent or parallel hole somewhere above 250 ft. Initially after completion, the water level was at 290 from ground level. The water level began dropping when hand bailed and all water recovered was bottled for chemical analysis without first purging the well of three casing volumes. The well was barely able to produce adequate quantity to fill the laboratory supplied sample bottle set. No additional water was recoverable for the next several days and the hole was dry a month later.