2009-04-29_PERMIT FILE - C1982056A (5)

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along the banks no more than a few feet wide. The landward limit of this wetland type was used to define the jurisdictional limits of the primary channel (Exhibit 16D, Map 1 W). Floodplain is virtually non-existent on the north side of the channel, being confined by sandstone outcrops. No attempt was made to delineate wetlands in the floodplain on the south side of the primary channel as potential disturbance is to be limited to the north side. Casual observation of this area indicates portions would likely qualify as wetland using the Cowardin System; however, the majority of this area would most likely not meet the soil and hydrology parameters applied by the USACE. Based on the findings of this survey, it is concluded that the area(s) disturbed for the 18-Right Ventilation Shaft pad and associated access roads do not impact jurisdictional wetlands or other Waters of the U.S. 6-Main North Ventilation Installation (TR05-48) In accordance with Section 404(b)(1) of the Clean Water Act (40 CFR 320), a routine wetland delineation was previously performed for areas affected by proposed construction of the 18-Right and 6-Main North Intake Shafts, and the associated access roads. Wetland boundaries were determined in the field in accordance with the US Army Corps Wetland Delineation Manual (Technical Report Y-87-1, Jan. 1987). Habitat Management Inc. conducted the surveys on October 21, 2003. "Normal" site conditions prevailed at the time of surveys. A detailed report for the wetland delineation is provided in Exhibit 16D, Wetland Delineation Report, RAG Twentymile Coal Company, Fish Creek Vent Shaft, October, 2003. Detail maps for the wetlands delineation for the 6-Main North Ventilation Installation are provided in Exhibit 16F. The following summarizes those portions of the report that are relevant to the 6-North Mains Shaft facilities and roads. The proposed 6-Main North Ventilation Shaft and access road are located in Section 17, of TSN, R86W, in Routt County Colorado (Map EX16F-M1). The proposed shaft pad, at an elevation of 6,765', covers approximately 11.1 acres. The wetland survey covered an area encompassing approximately 38 acres including the pad and surrounding areas. The access road is approximately 2,930 lineal feet from start to end points. The access road begins at the existing Northwest Mains Ventilation Shaft, located near the edge of the Fish Creek floodplain. The proposed access road proceeds northwest, terminating at the proposed intake shaft location. A 100-foot wide corridor was surveyed along the entire length of the proposed access road alignment, extending approximately 50 feet perpendicular on either side of the road centerline. Identified wetlands within the 38-acre survey area, are located north of the proposed shaft pad and are confined to areas within an intermittent drainage indicated by a dashed blue line on the USGS topographic map of the area. This drainage shows considerable variation within the survey area. The upper reach has poorly defined banks, but there is sufficient ongoing scour to prevent establishment of persistent vegetation communities. Midway along the surveyed reach, the channel is deeply incised and the banks are well defined. The bottom and banks of the channel support hydrophytic vegetation in areas where groundwater seeps are evident (refer to Exhibit 16D, Photos 5 and 6, and Map EX 16F-M 1). The proposed shaft pad has been relocated to the south of the identified wetland areas, such that approximately 10.6 of the 11.1 acres are outside of a 100' drainage buffer. In the northern central portion of the pad area, the remaining 0.5 acres of pad disturbance will fall just outside of a 50' buffer for the drainage and associated wetland areas. The 0.5 acre area is needed so that vertical power-drop boreholes can be aligned with the underground mine workings. Aside from this very limited area, planned project disturbance will only affect upland grass and shrub plant communities. Western Mining District (Panels 12-Left through 17-Left. PR06-07) No new surface facilities are currently planned as part of PR06-07. Also, as part of PR06-07, initial development of main and sub-main entries will occur under a portion of Fish Creek and its Alluvial Valley Floor. Because support pillars are retained in the entries, no subsidence is anticipated in conjunction with these development activities. Because no surface facilities are planned and no subsidence will occur, no impacts to any Threatened, Endangered, or Sensitive plant species are anticipated. TR09-66 2.04-61.2 02/17/09