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A. J. Waldron -3- June 29, 1995 hydrologic impacts of mining during the year, why did the quality of the alluvial wells improve for the 1993 sample? The 1993 AHR indicates that AA1 and AA3 both saw a reduction in most of the pertinent water quality except AA3 in which conductivity showed an increase. The water quality did not really improve. The reduction in most of the pertinent water quality parameter was generally within expected ranges. 2. The 1993 AHR would assess the hydrologic impacts of mining during the next year which would be 1994. Mining in 1994 was restricted to the western portion of the reserve. Retreat mining was performed in the First North Mains. The Third West Mains were advanced. The Second North Mains were mined along with panels 14, 15, 16 & 17 (see Map 9A). Since the springs in Lone Pine Gulch (G-26A, G-26B and CR-12) are protected from the impacts of subsidence, no hydrologic impacts were anticipated or noted for the mining performed in 1994. 3. There is a table in the 1993 AHR which presents that amount of water imported to the mine. 1994 Annual Hydrologic Report 1. The Division asks as part of the required assessment of hydrologic impacts of mining during the year, why does there continue to be no flow in the lower french drain and why is there no flow at spring CR-12? The lower french drain was installed to dewater the toe of the area that slid in 1993. It was installed to drain the toe of the slide if any free water was present. Evidently no free water is available at the toe of the slide since the lower french drain has been dry since it was installed. The limited data available on spring CR-12 indicates it is usually dry. The baseline data in the permit is restricted to two monitoring events 9/93 and 11/93 and both are recorded as dry. The 1994 AHR would assess the hydrologic impacts of mining during the next year which would be 1995. Mining in 1995 is projected to occur with the retreat of the Third West Mains and the development of panels to the south in Section 20. Since there are no water resources in the area to be mined in 1995, there are no projected hydrologic impacts. 3. There is a table in the 1994 AHR which presents the amount of water imported to the mine. General Recommendations and Questions Enclosed is the requested monitoring location map.