2016-08-10_GENERAL DOCUMENTS - M1981185 (2)

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Final -Restoration and Compliance Plan for May Day Idaho Mine Complex Administrative Order for Compliance, Docket No. CWA-08-2012-0011 survival of willows, but the growth of the willows is less than robust which possibly indicates an inadequate water supply. A total of 0.04 acre of mitigation has been constructed. None of the required native riparian trees (60 trees at a ratio of 2:1) have been planted. 5.2 WETLAND DELINEATION Wetlands and other Waters were delineated at the Chief Portal and Mine Access Road sites. Wetlands were delineated following the methods in the "Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region" (Corps May 2010). The occurrence of plant species in wetlands was determined from recent (May 2012) update to the "National List of Plant Species That Occur in Wetlands: Region 8 (Intermountain)". Fieldwork was completed on June 5, 2012, and included observations of vegetation communities, soils, and hydrologic conditions. The plant community was characterized based on the species present and their dominance. Pits were dug to observe soils, and soil colors were determined using Munsell Soil Color Charts (Kollmorgen Instruments 1988). Observations of surface and groundwater were made, and indicators of wetland hydrology were evaluated. Observations were recorded on WDDFs from the delineation manual, and photographs were taken to document conditions. Wetland boundaries were marked in the field with pin flags and mapped using asurvey-grade GPS. WDDFs are provided in Appendix D and photographs are included in Appendix C. The results of the wetland delineation were described in Section 5.1. 5.3 PROPOSED I~HYSIGAL CORIDITIONS The proposed plans for each site were developed based on available alternatives and input from the Corps during a field meeting. 5.3.1 Chief Portal Area An evaluation of potential alternatives for the Chief Portal was completed by BWC, as described in the June 29, 2012 memorandum to Kara Hellige, Corps (see Appendix E). Alternatives evaluated included: retaining wall design, fill/culvert plan, and knee-wall plan. The alternatives were evaluated in terms of their cost, logistics, technological considerations, and resource impacts. As described in detail in the memorandum in Appendix E, the preferred alternative is June 2016 Bikis Water Consultants, a division of SGM Page 10 Case 1:16-cv-02008-WYD Document 2 Filed 08/08/16 USDC Colorado Page 40 of 82