2010-04-08_PERMIT FILE - M2008012

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Geologic Log — supplement to GW S 33 1 for NH-48088 NRAW1 Depth 'type Grain Size Color Water {ft) 0-5 sandstone f m It gra 5 -30 sandstone f m buff to pale red brown 30 -40 1 sandstone f buff to pink brown 40-45 siltstonelshale siit shale gra 45-50 sandstone of f aLay 50.70 sandstone f buff to ink brown 70-80 sandstone, some shale f m red brown 80 -100 sandstone f - gra y 100 -105 sandstone & shale of yellow brown 105 -195 siltstonelshale silt & clay red brown to maroon 915 -120 siltstone to sandstone of brown 120 -140 sandstone I f At gray top, red brown bottom f 140 -145 shale clay red brown 145 -160 silty sandstone silt -vf pale pink brown 160 -170 sandstone f -rn red brown 970 -180 mudstone siltv dk red brown, blue Rreen 180-200 mudstone to sandstone clay - of red brown 200 -220 sandstone I of f m tan to red brown 220 -240 sandstone f -m gray to yell ow brown 240 -260 sandstone sil -vf gray to yeliow brown 260-280 sandstone silty -vf yellow brown — some thin variegated sh — blue ra , olive, red 280 -300' sandstone off pale yellow brown Entrada Ss ? 1--290 300-316 silt and sandstone to slit - f yellow brown to It gray mudstone? 315 -320 shale/mudstone clay-silt red 320 -340 mudstone cla -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). Tile borehole was backfilled with native materials to 310 feet, then PVC casing was set as described on the attached form GWS'j 1. Twenty -two 50 -lb sacks of 10-20 sand filter pack were poured into annulus which subsequently had a measured Ievel 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 groun s�u�ace with hydrated bentonite, and cement from 3 feet to the surface. A cement surface cap was constructed and a locking well head casino protector installed. Thus, the monitoring well was constructed with perforations and sand from 250 to 31.0 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. T1ze 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.