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Memo to Matthew S. Hayes - 2 - May 17, 1989 waters are of a calcium bicarbonate type with relatively low Total Dissolved Solids (TDS) levels. Section 2.8 delineate both streamflow and water quantity. Two reservoirs are located within this drainage. The northernmost impoundment is called Minnesota Reservoir. It is located on Dry Fork. It has a decreed capacity of 1,285 acre feet. Useable capacity is limited by structural parameters imposed by the State Water Engineer to about 500 acre feet. Water is diverted to this reservoir from Little Gunnison Creek via the Deep Creek Ditch. Based upon ditch and West Elk Coal Company (WECC) records approximately 1,000 acre feet of water is transferred by this ditch. The second impoundment is called Beaver Reservoir. It is located on the East Fork of Minnesota Creek in the southeast corner of the permit area. This reservoir has an absolute decreed capacity of 1,620 acre feet plus a conditional decree for 522 acre feet. Both reservoirs store spring runoff for irrigation purposes. Stored water is used up by late August or early September. The valley in which Paonia and Somerset are located is semiarid with extensive agricultural activities. The average annual precipitation is about fifteen inches. Mean annual precipitation rates increase with elevation. The summit of Mt. Gunnison receives about forty inches of precipitation. Snowfall in the area averages about fifty-eight inches per year. Undisturbed surface waters are naturally impacted by spring discharges. 114 springs have been identified on the life of mine area. It has been calculated that these springs contribute 11% of the flow to Lower Dry Fork, 4% to Lick Creek, 12.6% to South Prong and 0.9% to Horse Creek. Excluding Sylvester Gulch data, the springs are estimated to contribute 6.2% during the low flow runoff period. TDS concentrations vary significantly during the water year and range from 252 to 1,215 mg/1. The average TDS levels appear to be between 400 and 600 mg/1. During the low flow part of the water year, numerous parameters can exceed recommended limits set for drinking water by the Colorado Department of Health. Water Rights and Useage The "F" Coal Seam outcrops upslope from the Minnesota Reservoir, however, some of Minnesota Creek's northernmost tributaries are underlain by the F Seam. Mining has been projected to occur beneath Dry Fork and Lick Creek. Beneath perennial streams, coal extraction will be limited to 50%. 200 foot buffer zones plus zones of influence (subsidence) up to 560 feet are planned beneath perennial streams. Surface water flow still has the slight potential to be impacted by mining. A multifaceted monitoring program has been in effect since 1981. Extensive baseline data has been collected. Based upon this monitoring, it is hoped that initial impacts will be detected. The wide range of precipitation values from year to year may make this judgment difficult. WECC has committed to a rapid response to surface water flow impacts on the permit area. For this purpose, certain supplies are to be stockpiled at the property. These supplies will consist of: 700 feet of steel well casing. A suitable pump to deliver water from underground collection sites to the impacted surface site. 500 feet of 36" corrugated pipe. All necessary couplings, seals, et al.