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Final -Restoration and Compliance Plan for May Day Idaho Mine Complex <br />Administrative Order for Compliance, Docket No. CWA-08-2012-0011 <br />There are no wetlands in the Chief Portal area, including along Little Deadwood Gulch, due to <br />the lack of soil development, steep slopes, and a wetland water supply. NWI mapping for the <br />area (see Figure 4) does not indicate any wetlands or other Waters in the area. Soil mapping <br />(see Figure 5) shows the soil at the portal to be Nordicol very stony sandy loam, with 6 to 25 <br />percent slopes. This is not a listed hydric soil. Photo 4 (see Appendix C) shows the soil in the <br />area. <br />Vegetation in the Chief Portal area is mesic, mixed forest. The site is located in a cool, shaded <br />forested area. BWC completed Wetland Determination Data Forms (WDDFs) from the <br />"Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western <br />Mountains, Valleys, and Coast Region" (Corps, May 2010) in the area (see Appendix D). As <br />shown on these forms, dominant species include quaking aspen (Popu/us tremu/a), fir (Abes <br />spp), dogwood (Corpus spp), willow (Sa/ix spp), currant (Ribes spn), and elderberry (Sambucus <br />spp), with an understory of mountain brome (Bromus marginatus), cow parsnip (Herac%um <br />/anatum), bluebells (Mertensia ci/iata), and false Solomon's seal (Maiathenum racemosa). <br />Fill material is thought to have been placed in the channel of Little Deadwood Gulch years ago <br />(in the 1910s) to explore the May Day vein. Additional work was completed prior to 1926 to <br />connect the Chief Portal to an underground shaft to the May Day Mine. Calculations indicate <br />that around 315 cubic yards (CY) of soil and rock were placed in Little Deadwood Gulch from <br />this early work. This included construction of a fill pad in the creek with a culvert. The remains <br />of the old culvert still exist in the fill. <br />More recently, in 2009, the previous operator of the mine placed soil and rock from the area <br />(scar) above the portal on top of the historic fill in piles. The footprint of the historic fill was not <br />increased. The measured volume a# the more recent fil! corresponds we!! with the estimated <br />volume of the scar above the portal (245 CY), which supports the piles as being from the scar. <br />Therefore, the Chief Portal site consists of apre-Section 404 fill in the drainage with more recent <br />fill on top. The fill consists of soil and rock from the mine portal workings and this material is <br />believed to be free of chemicals and pollutants. <br />The entrance to the portal itself is unstable and has collapsed partially. The old access road to <br />the portal has become invaded by weeds but is still usable to small four-wheel drive vehicles. <br />June 2016 Bikis Water Consultants, a division of SGM Page 8 <br />Case 1:16-cv-02008-WYD Document 2 Filed 08/08/16 USDC Colorado Page 38 of 82