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OOr.S~2 CESPK-CO-R Page 5 Public Notice Number 200375243 I, W~tl:mrl rrf"~tion: Wetland creation is proposed below the embankment and upstream of the proposed facility to mitigate for the 2.5 acres of emergent wetland impacts within the reservoir's footprint. Impact to emergent wetlands would be mitigated for at a ratio greater than I: I. 2, Rip~rinll rornrlnr Rf't;t[)r::ltion ;]ncl r;nh::lncemp.nt: Additional mitigation may include enhancement and/or restoration of existing riparian areas along Govemment Draw and Long Hollow, The applicant intends to work closely witli the US Army Corps of Engineers and other agencies to best address the basin needs in ternlS of mitigation opportunity, Construction of the proposed project will create a reservoir with a fluctuating water surface. These conditions along with the steep terrace walls do not favor mitigation opportunities along the shoreline of the proposed reservoir. A mitigation wetland downstream of the dam embankment is proposed. Other mitigation opportunities exist upstream from the proposed facility in the Long Hollow and Government Draw drainage, Surface water and shallow groundwater would provide for wetland hydrology, Mitigation sites will be constructed by excavating to existing water sources and by expanding existing riparian wetland corridors. The mitigation areas will be more diverse and provide increased functional values compared to the impacted wetlands. Wetland mitigation areas will have multi,layered vegetation, including trees and shrubs. The mitigation wetlands will provide functions for water quality enhancement, wildlife habitat, and groundwater recharge. Earthwork will be done after construction of the dam embankment. All mitigation sites will be planted with native vegetation using potted nursery stock and/or seeded, Wetland creation areas will be fenced to prohibit livestock grazing. Riparian wetlands above the proposed reservoir lack shrubs and trees. The presence of shrubs and trees Within riparian areas enhance wetland functions, especially for wildlife habitat. Therefore, the applicant proposes to plant shrubs and trees along approximately 20,000 LF of riparian wetland adjacent to Government Draw and Long Hollow 10 restore and improve the riparian vegetation. Restoration opportunities upstream and downstream of the proposed reservoir include the use of mechanical and vegetative bank stabilization techniques that will improve the stability of the drainage, The design of bank stabilization measures will depend on factors such as slope angle, soil type, and Ilow regime. Vegetative measures can include seeding, sodding, and/or planting trees and shrubs. Mechanical measures may include surface roughening, erosion mats/nets, terraces, blankets, riprapping, mulch, and soil seals. Enhancement would include plantings or nursery stock trees, shrubs, and herbaceous vegetation to complement existing conditions and increase biodiversity. Wntpr Qll;:J Ii ty Prot~('fion Appropriate soil erosion and sediment controls would be implemented and maintained during construction of the proposed reservoir. Mitigation of water quality impacts to native and T &E species of concern as a result of the proposed reservoir are being addressed with the appropriate agencies. Any mitigation solutions, including a multi-level release design from the reservoir, resulting from discussions with the appropriate agencies will be incorporated into the construction, operation and maintenance of the reservoIr. ADDITIONAL INFORMATION: The applicant has requested water quality certification tram the Colorado Department of Public Health and Environment, Water Quality Control Division in accordance with Section 401 of the Clean Water Act. Written comments on water quality certification should be submitted to Mr. John Hranac, Planning and Standards Section, Colorado Department of Public Health and Environment, Water Quality Control