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• • r~: Oround Water ~' The Quaternary elluvial deposits and the Neeaverde Formation are the primary hydrogeologic unite within the proposed lease area. The Quaternary alluvium ie aeeociated with the North Fork of the Gunnison River. Static water levels in this alluvial aquifer occur within several feet of the ground surface. Water yields can approach 500 gpm due to the high transmieaivity of the alluvial gravels. Because of this high tranemiesivity and hydraulic connection to the surface water of the North Fork, water quality between the two are similar. Essentially all ground water in the Heeaverde Formation ie aeeociated with secondary porosity (fracturing or natural bedding planes), which ueuelly occurs in a non-continuous fashion. Where areas exhibiting secondary porosity intersect the Quaternary alluvial deposits of the North Fork, recharge to the Heeaverde Formation can occur. Both the B and C coal beds underlie the North Fork in the vicinity of the proposed lease tract, however, the degree and extent of secondary porosity in these unite is unknown. Several water wells (Colorado State Receipt Numbers: 9110248, 9110249, 9110250, and 9110252) located between the North Fork and southern proposed lease boundary encountered water-bearing sandstone and shale unite in the Neeaverde Formation, ranging in depth from 34 to 67 feet below the ground surface. This provides evidence that at least some members of the Neeaverde Formation are water-bearing in the vicinity of the proposed lease tract. Possible hydraulic connection to surface water also occurs along joint systems in the Neeaverde Formation that coincide with the overlying ephemeral gulches. Recharge to the Neeaverde Formation from these joints would be mainly during the snowmelt season. Generally, water yields of the Neeaverde Formation are lees than 10 gpm. In areas where secondary porosity ie high, water yields can be much greater. Water quality in the Heeaverde Formation is an alkaline sodium-bicarbonate type, with Total Dissolved Solids concentration ranging from several hundred to several thousand mg/1. J. Socioeconomic Although the proposed lease tract is located in Gunnison County, moat of the workers live in Delta County and the mine buys locally ae much ae possible. Thaae local expenditures by the mine affect mainly Delta County. Delta; County, thus, ie the focus of the economic impact area analysis. Between 1980 and 1990, Delta County experienced changes in its population. Th~z 1980 population was 21,225 and the 1985 population was 23,466. The 1990 ce.neue puts the population at 20,980, a decrease of one percent over the 1930 population count. See Table 1 for the population of towns in Delta County. The Colorado Division of Local Government has made population projections for the period 1990-2015. Delta County ie projected to have a population of 22,280 by 2015 or a 6.2 percent increase over 1990. Employment for Delta County increased from 7,600 in 1989 to 8,124 in 1990 or a '1 percent increase according to data from the Bureau of Economic Analysis. Hi:ninq employment was 345 in 1960 and dropped to 98 by 1989, a 72 percent decrease. In 1989 mining employment represented one percent of the county's employment. Nininq earnings were 10.8 million in 1980 and decreased to 4.6 million by 1989. Hining earnings represented 13 percent of non farm earnings in 1980 and 4 percent of non farm earnings in 1989. • 12