2012-10-01_REVISION - M1977306 (23)

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4.2 Surrounding Area Characteristics Most of the affected area at JD -9 is classified as a Pinyon- Juniper Woodland range. A portion of the highland to the north of the mine consists of steep rock outcrops that support little or no vegetation. Associated secondary species include: Indian ricegrass Fendler three awn Blue grama Rabbitbrush Galleta Snakeweed Cheatgrass Fleabane None of these species are currently listed on the BLM Colorado Sensitive Species List found at www.blm.gov /co /st /en/BLM Programs/botany /Sensitive Species List .html. The vegetative cover on JD -9 may be classified as scattered to sparse. Most Pinyon- Juniper stands do not reach over twenty feet in height. Shrubs, grasses and forbs remain closely cropped by grazing and wildlife use. Grassy parks are heavily infested with patches of prickly pear cactus. For a map of how the vegetation relates to the topography and soil types, see Exhibit U — EPP. The main types of soils to be disturbed at the JD -9 site are Bodot, dry-Ustic Torriorthents complex (Soil map unit 23) and Pinon - Bowdish -Rock outcrop complex (Soil map unit 76). Ecological site descriptions are not yet available in Colorado. However, a Rangeland Site Description associated with both these soil types has been provided by the Department of Agriculture, Natural Resources Conservation Service, and is included in this exhibit. The Rangeland Site Description discusses coverage percentages for each species including the relationship of current vegetation to soil types associated with Pinyon- Juniper sites. 4.3 Existing Storm Water Structures Presently, there are several constructed stormwater control structures at the site, consisting of diversion channels and berms, and detention ponds. The most prominent feature of the site is the steep topography and a large drainage located on the west side of the mining area that drains the highlands area above the site and ultimately the operational area of the JD -9 Mine. Existing stormwater structures attempt to divert offsite runoff around the mining area and intercept onsite runoff in ditches and detention ponds. Runoff from the steep hillside above the mine site is diverted by berms or ditches that route water around the waste rock pile and eventually to the major drainage. Improvements in these structures will be necessary with future mining plans. These improvements are illustrated in the design drawings found in the attachment to this document. Onsite stormwater structures include a ditch along the western margins of the waste rock pile that intercepts runoff from the waste rock pile and detains the water in a small pond located near the southwest corner at the toe of the pile. A secondary containment system is located along the ESWMP -3