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Flow (GPM) Meter Tot. Minutes Gal/period Ave. Date Time From Pieter 000 al Elapsed 000 al Disc. 04/20/84 1433 80 35,697 20,176 1,278 63 04/27/84 1415 75 36,445 10,062 748 74 05/04/84 1222 85 37,165 9,967 720 72 05/11/84 1135 90 37,946 10,033 781 78 05/30/84 1213 70 42,087 27,398 4,141 151 05/31/84 1008 150 42,294 1,315 207 157 06/01/84 0946 150 42,503 1,418 209 147 06/08/84 0940 140 43,996 10,074 1,493 148 06/15/84 0950 135 45,429 10,090 1,433 142 06/22/84 0655 150 46,940 9,905 1,511 153 The data presented on Table 4 indicates that the inflow varies seasonally. When compared to the stream flow data for the Williams Fork, which would be representative of stream flow data trends in the Yampa River, the inflow appears to lag approximately one month behind the changes in stream. Table 5 contains the flow data from the Williams Fork River gaging station for the period of February 1, 1984 through July 10, 1984. A comparison of the 2 West 1 Left Panel and Williams Fork River discharge data indicates that the inflow to the 1 Left Panel could be coming from /infiltration from the Yampa River. The amount of inflow from surface water is possibly a maximum of 159 gpm and an averages of 85 gpm. The amount of surface water predicted to inflow to the No. !i Mine on the west side of the Yampa River was 45 gpm (see the permit application for the No. 5 and No. 9 mines, Table~Cr-20f). Given the variability in the hydrologic factors involve the e measured number is very close to the predicted value. Also, this small difference will not •31 ter our previous estimates of the net effect of the mining on the hydrologic balance. A study of the results indicate that a number of uncontrollable variables, both in the ground water system itse]f (i.e. modified local gradients), and in mine conditions (flooded or sealed areas) manifest themselves during the study. The resulting variation points out the difficulty in conducting inflow studies on an annual basis to address the MLRD's contention that it is imperative to identify what areas of the mine are drying up or have started producing water. The inflow predictions Empire Energy made in the permit application are reasonable, and Empire Energy provided for an approach for conducting additional inflow studies if needed. This was based upon the commitment to conduct inflow studies if the mine discharge exceeded the predicted discharge (which is the mine inflow) by 20%. This recognizes the fact that perturbations in the discharge rate will be caused by intercepting significant quantities of water, and this will require a new inflow study. It is Empire's intentions to request, through a technical revision, that the requirement to do an annual inflow study be abandoned, and the stipulation numbered 3 of the permit issued October 19, 1983 be reinstated.