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and Sagebrush/Meadow Vegetative Cover, respectively. The data generated from Pasture 13 was used to characterize Table 3. The data used to describe Table 4 was obtained from 1986 field surveys and from the TCC Life of Mine Permit submittal. Table 4 represents the native sagebrush/meadow vegetation type and portions of land which have been previously irrigated. Within Pasture 13, the total vegetative cover is 75.2%. Of that amount, grasses cover 62.7%, grasslike plants cover 2.7%, and forbs comprise 9.8°L. The moderately tolerant species, smooth brome and intermediate wheatgrass, cover 31.7% of the area. Moderately tolerant grasslike plants cover 2.7%. The total coverage of moderately tolerant plants is 34.4%, or 45.7°,6 of the relative cover composition. Both timothy and clover are found within the pasture and cover .5%, which is .7% of the relative composition. As reflected in Table 4, the total vegetative cover within the Sagebrush/Meadow vegetation type is 88.6%. Grasses cover 45.1%, grasslike plants comprise 10.7%, forbs cover 20.6% and woody plants cover 12.2°k. The moderately tolerant grass species, crested wheatgrass, slender wheatgrass, mountain brome and wheat, are found in this region. Similar moderately tolerant plants, intermediate wheatgrass, tall fescue, foxtail barley, Idaho fescue, and sheep fescue were also found in the Fish Creek area as were sedges and rushes. The total coverage of moderately tolerant species is 18.2%, or 20.4% of the relative cover composition. The moderately sensitive plants in this area include redtop, timothy, and various clovers. The coverage of these plants is 3.3%, or 3.7°L of the relative cover composition. In summary, the irrigated pastures of Middle Creek support 41.6% vegetative cover of moderately tolerant species and 5.6% of moderately sensitive species. This area covers about 139 acres of irrigated land. Pasture 2 production data indicate 64.1% of the 1660 pounds of oven dried forage per acre is of moderately tolerant species and 25.3% is of moderately sensitive plants. There are about 91 acres in Pasture 2. The irrigated pastures of the Trout Creek alluvial valley floor region support 25.8% of moderately tolerant species and 15.3% of moderately sensitive species. This region contains about 246 acres of irrigated land which is generally cut for hay, 42 acres of irrigated land which is usually managed as pasture, and 69 acres of irrigated land which is more typical of a sagebrush/meadow type community. Production estimates for Pasture 11 indicate moderately tolerant species supply 27.9% of the total amount and moderately sensitive plants are 34.6%. Approximately 4550 pounds of oven dried forage are produced. Pasture 11 covers about 12 acres. The portion of the Fish Creek alluvial valley floor which is currently irrigated, Pasture 13, supports about 34.3% of moderately tolerant species and .5% of moderately sensitive species. The Sagebrush/Meadow region has 18.2% of moderately tolerant plants and 3.3% of moderately sensitive plants. These areas cover about 57 and 1253 acres, respectively. The Colorado Mined Land Reclamation Division (CMLRD) has chosen to establish the material damage standard for irrigation waters at 1000 umhos/cm. This standard is based on a conversion factor of 1.5 to describe the salinity of the soil and the premise that moderately sensitive species dominate the areas of concern. Information and data obtained by TCC do not