2008-09-04_HYDROLOGY - M2007044 (2)

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Page 4 September 2, 2008 PR Spring emanates from near the base of the upper Salt Wash Member sandstone located on the reclaimed bench approximately 500 ft north of the main Packrat Mine portal/dump. PR Spring is characterized by flow from one or more fractures in the Salt Wash outcrop near the base of the old roadcut (Photo 12). This flow is captured by a pipe and possibly other buried collection structures and conveyed to a round galvanized metal stock tank (Photo 13). Water discharges from the tank by way of a metal pipe to the downslope side of the reclaimed road. The only other surface water potentially associated with the ore-bearing zone was observed in the draw immediately below the Packrat Mine dump (Photo 14). This seepage was minimal, estimated at less than 1 gpm. The seepage may be from transient storage of infiltrated precipitation within the dump materials. The presence of moss and algae in the drainage indicated that the seepage had been present for some time. The seepage was observed and present in the drainage for at least 150 ft downstream of the dump; no reconnaissance was conducted beyond this point. The Whirlwind Mine water treatment facility, which is located upstream of the Packrat Mine dump, was not discharging at the time of the field reconnaissance. A number of mine portals associated with past mining activity in the Salt Wash Member were observed during the reconnaissance. These include the Bonanza Mine, Dutchman Mine, Packrat Mine, Lumsden Mine, and Rajah 49 Mine. Each of these mines may have had multiple adit/portals associated with them. The larger adits were sealed with steel bat grates; a few small rock-plugged workings were also observed. Inspections of each portal area showed that all were dry with exception of the Dutchman Mine, where seepage from the back was observed and small pools were present approximately 30 ft inside the portal. Although past discharge has been reported at the Packrat, Lumsden No. 2, and Rajah 49 Mines, no discharge was observed from any of the mine workings visited. Reconnaissance upslope of the Brushy Basin Member outcrop area was limited to the vicinity of DP Spring and upper Lumsden Creek. DP Spring occurs near the Lumsden Fault and within a few . hundred feet of Lumsden Creek. Reconnaissance in the vicinity of DP Spring revealed an undulating ground surface characteristic of landslide terrain. The spring's source water area is located upslope (west) of the spring discharge pipe and stock tank in what may be the head of an ancient rotational landslide that displaced Burro Canyon Sandstone. Groundwater, which was likely related to the slide, now emanates and forms shallow surface water pools in the upper landslide mass. Sampling and Analysis Reconnaissance on June 19" focused on collection of groundwater samples from the main sump in the Whirlwind Decline, and surface water samples at PR Spring and three locations in Lumsden Creek. DP Spring was not sampled for water quality analysis. Flow measurements were recorded at DP Spring and at the sample locations where feasible [PR Spring, Lumsden Creek DN (Lumsden Creek below the Dutchman Mine dump)]. Flow in the drainage below the Packrat Mine dump was not considered of sufficient volume to sample. Water quality instruments were calibrated at the beginning of the field work on June 19'x'. Field sampling forms are presented in Attachment B. The field parameters collected for each sample location are summarized in Table 1. PR Spring was sampled directly from the metal pipe that conveys flow into the stock tank (Photo 13). Flow was measured with a bucket and stop watch. Turbidity was low as the water appeared very clear. Water emanating from the exposed outcrop did have a stringy milky-like film substance in part of the rivulet observed. Weans090108.doc