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Final Mitigation Plan for Long Hollow Reservoir <br />La Plata River Mitigation Site (Permit No. 200375243) <br />2.4 Baseline Information <br />Long Hollow Reservoir (LHR) is proposed to be constructed in portions of Sections 29, 32, and <br />33, Township 33 North, Range 13 West in La Plata County, Colorado in Long Hollow, <br />approximately 0.5 miles upstream of its confluence with the La Plata River. Characteristics of <br />the wetlands and other Waters of the U.S. impacted by the Project are described in the February <br />2008 Revised Mitigation Plan. The impacts to wetlands and other waters of the U.S. from the <br />Project are shown in Table 1. <br />Table 1. Summary of Impacts to Wetlands and Other Waters <br />Watershed Emergent Wetland Perennial Drainage Ephemeral Drainage <br />Government Draw 46,480 s ft <br />1.07 acres 7,040 LF 700 LF <br />Lon Hollow 62,156 s ft <br />1.43 acres 11,520 LF 1 480 LF <br />Total 2.53 Acres 18,560 LF 2,180 LF <br />Most of the LPRMS is a relatively flat, reclaimed gravel pit with a 4.2-acre pond (see Photos 1 <br />and 2 in Appendix A and Figure 2). It is proposed to excavate unmined aggregate from an <br />approximately 1.2-acre parcel in the northeastern portion of the site in order to establish <br />wetlands. Unmined aggregate will be removed and stockpiled onto the existing 112 State Mine <br />Permit area. <br />The reclamation that has been done at the site was completed according to the "Reclamation <br />Plan" in the mine permit. Reclamation has included backfilling and grading the area east of the <br />pond, placing topsoil, and then revegetation with an upland seed mix. The area proposed for <br />wetland creation is on the east side of the pond, and within 2 to 5 feet in elevation from the <br />normal water level of the pond. <br />A subsurface drain system was constructed along the south end of the site during reclamation to <br />reduce groundwater inflow to the pond (see Figure 2). The system includes perforated PVC <br />pipe and two 6-inch flexible drainpipes, with solid pipe connected to a series of air-vent <br />manholes. The system ties into a valve box near the southwest corner of the lake that can <br />discharge either to the lake (during times of no water rights calls on the river) or to the river <br />(when there is a call). This subsurface drain system will be removed during construction of the <br />wetlands. <br />August 2010 Bikis Water Consultants, LLC Page 3