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Twentymile Coal Company has collected additional information in order to further characterize the alluvial valley floor regions associated with Foidel, Middle, Trout and Fish Creeks. Vegetative cover and composition were determined from information obtained during the 1984 and 1986 field seasons. The location of the transects conducted during the 1986 field season are shown on Map 1, Salt Loading Study. Fifty meter transects were randomly located in the field. Ten-point frames were placed at five meter intervals to yield 100 hits per transect. Each transect was treated as separate datum for the purposes of determining vegetative cover and composition. Production data was obtained for Pastures 2 and 11. Individual species contained within the volumetric projection of quarter meter plots were clipped, oven-dried, and weighed to the nearest .1 gram. Data collected from three plots for each transect were averaged to describe a specific transect. The vegetative cover and production of the two pastures are denoted on Table 5, Pasture Two Vegetative Cover and Productivity and Table 6, Pasture Eleven Vegetative Cover and Productivity. The location of the 1984 field season transects are depicted on Map 18, Premining Vegetation, of the Foidel Creek Mine permit submittal. The vegetative cover for these transects was obtained using a ten-point ocular frame. Each transect was described using 100 hits. The 1984 transects were used in conjunction with 1986 transects to describe the sagebrush/meadow vegetation type associated with the alluvial valley floor region of Fish Creek. Data obtained from individual pastures were merged to describe particular alluvial regions which might be affected by the Foidel Creek Mine operations. For example, Pastures 1 and 2 are both irrigated with water diverted from Middle Creek; thus, they were used to describe the Middle Creek alluvial valley floor region. Table 1, Middle Creek Alluvial Valley Floor presents the data of those pastures. Pastures 7, 8N, 8S, 10, 12E, 12W, 14, 15N, AND 16S are irrigated with water diverted from Trout Creek. The data from these 9 pastures were used to compose Table 2, Trout Creek Alluvial Valley Floor. The Fish Creek alluvial valley floor region is described using the data of irrigated Pasture 13 and the native sagebrush/meadow vegetation type. Table 3 and Table 4 reflect the vegetative cover and composition of the Fish Creek alluvial area. In the evaluation of the alluvial valley floor regions, two small areas were excluded from consideration. One of the areas is located immediately west of Pasture 1 along Foidel Creek, noted as Pasture 19 on Map 1. The other area is located downstream of the Foidel Creek and Middle Creek confluence, in the area denoted as 18 on Map 1. These areas were not evaluated with the other pastures because both are small parcels of undeveloped rangeland (about 10 acres each) which do not contribute significantly to the productivity of the surrounding farm/ranch operations. The plant species growing within the specific irrigated and alluvial valley floor regions were categorized in terms of tolerance to soil salinity. The particular categories of moderately sensitive and moderately tolerant are based on the article "Crop Salt Tolerance - Current Assessment" by Maas and Hoffman (1977), as referenced in Rule 2.06.8(5)(C)(i)(A).