2012-10-01_REVISION - M1977305 (15)

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Blue grama Rabbitbrush Snakeweed Galleta grass Russian thistle Sand dropseed Sunflower Scarlet falsemallow Pea family members 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. Between the steep south facing slope and the sagebrush park lies a strip of pinion juniper whose vegetative cover approximates six percent. Moving from the park towards the hillside and portal area, the soils trend is to grade into a clay loam from a loam. The average height of the dominant vegetation ranges from 10 to 20 feet. The associated pinion juniper stands thin out up the south facing slopes as the soil contains more clay and water infiltration deceases. Vegetative cover is less than 5 %, with an abundance of rock outcrops present. 4.3 Existing Stormwater Structures The portal is located near the path of a small, but well defined drainage that naturally collects offsite runoff from the northeastern side of the site (Offsite Basin 20). This 16 acre basin includes highland areas above the waste pile which discharge to the drainage and are routed around the eastern edge of the site. The drainage channel lies between the waste rock pile and the mine portal. The waste rock pile is mounded in the middle and sheds water to the east and to the west. Another small drainage is located between the vent 4A access roadway and the northwest edge of the waste pile. This drainage collects runoff from the western side of the waste rock and routes it to the southwest into small swales located between the road and the waste rock pile. This vent access roadway (to Vent 4A) is also located above the waste rock pile and intercepts runoff from the hillside above and to the north (Offsite Basin 10). These flows are also routed to the south around the west side of the site. At the present time, some runoff from the northern hillside flows over portions of the waste rock pile. There are currently no structures to prevent this runoff from either entering the eastern drainage or flowing to the south and west of the pile. The site, however, is not presently active and has been reclaimed. 5.0 Site Manager The site manager for the LP -21 will be responsible for implementing BMPs at the site during the operation of the mine, bi- annual stormwater inspections, maintenance of stormwater inspection records, and oversight of reclamation efforts once mining activities are completed. ESWMP -3