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2001 AHR McClane & Munaer Canvon Mines Paae 4 PRECIPITATION Based upon Bureau of Land Management records from a rain gage in Ashford Canyon, the 2001 water year experienced 13.05 inches of precipitation compared to average precipitation of 18.45 inches. The rain gage is not located at the mine but about 3.5 miles north at an elevation of 5895 feet compared with 5610 at the portals. The daily rainfall record is detailed on Table 2. The greatest 24 hour precipitation event during the year, 2.25 inches, occurred on August 15`". Figure 2 presents a graphical comparison of the 2001 total monthly precipitation and the average monthly precipitation for the period 1977 through 2001. EFFECT OF THE MINES ON THE EAST SALT CREEK REGIME Surface Water Due to the limited disturbance of the mines there is little chance any significant effect on the quantity or quality of the surface waters near either mine sites has occurred. As the Division notes in its approval package for the Munger Canyon Mine, the total area that will be disturbed by both mine sites amounts to 0.12 percent of the area of the East Salt Creek drainage basin above the mines. Surface water samples from East Salt Creek were obtained for three quarters during the 2001 water year. East Salt Creek was dry during the 3'tl quarter 2001 monitoring event. Results from all water samples collected in 2001 are presented in Table 4. The results from the samples collected from East Salt Creek above and below the mine site are generally the same for all parameters. The sample sites on McClane Creek were dry all four quarters. Groundwater Table 5 shows the results of groundwater sampling during 2001. The average static water level for the baseline years of 1981 and 1986 is also shown. Results of quality sampling are consistent with the results from previous years. GW-4 in close proximity to a hay field that is irrigated during dry periods and in danger of being eroded with an oxbow, has been replaced with GW-3. GW-3 is located adjacent to the road south of GW-4 and should be outside of the influence of the irrigation of the hay field. Refer to Figure 4.2-2 of the McClane Canyon Permit. The Division of Minerals & Geology has approved this substitution. Pond Discharges A significant isolated precipitation event occurred on August 15, 2001. This event filled the sediment pond at McClane and the pond overflowed. The overtlow amounted to mud and debris. The sediment traps at Munger Canyon and Loma did not discharge.