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Final Compensatory Mitigation and Monitoring Plan—Version 2.0 <br />Climax Mine Overburden Storage Facility Expansion (SPK-2013-00045) <br />March 2017 Bikis Water Consultants, a division of SGM Page 10 <br />soil is reported to have a gravelly and very cobbly silt loam texture in the upper 15 inches. Soils <br />in the upper portion of McNulty Gulch are Handran and Eyre soils. These are gravelly to stony <br />loam soils that are well drained or excessively well drained and have a depth to water of greater <br />than six feet. The Eyre soil is red in color. The bench in the upper part of the study area is a <br />mix of Cryoborolls, Cryaquolls, and Borohemists. The Cryoborolls and Cryaquolls are both well <br />drained with a depth to groundwater greater than six feet. However, the Borohemists reportedly <br />include peat up to 11.5 inches deep and have a seasonally high water table (0 to 1 foot). This <br />last soil would be considered to be a hydric soil. <br />Extensive soil pits were dug throughout McNulty Gulch to observe soil. These pits confirm the <br />above soil types, with red parent material occurring in the northeast part of McNulty Gulch. The <br />most common hydric soil indicators are redox dark surface and depleted matrix. A histic <br />epipedon occurs in fens. <br />5.1.3 Vegetation Communities <br />A total of 48 species were observed in the study area, many of which occur in wetlands to some <br />extent. Dominant wetland plant species in wetlands include: tufted hair grass (Deschampsia <br />caespitosa), Baltic rush (Juncus balticus), small-wing sedge (Carex microptera), marsh marigold <br />Caltha leptosepala), elephanthead (Pedicularis groenlandica), and plain leaf willow (Salix <br />planifolia). Bittercress (Cardamine cordifolia) and senecio (Senecio triangularis) occur in some <br />riparian wetlands at lower elevation. Most of the wetlands contain at least some willows (Salix <br />spp.) with an understory of herbaceous species, and have relatively distinct boundaries. Moss <br />is also relatively common in the wetlands. <br />5.2 LAKE IRWIN MITIGATION SITE <br />Lake Irwin is an area of perennially ponded water located on a former, mostly reclaimed, tailing <br />storage facility to the northwest of McNulty Gulch (Figure 1). It is located in a relatively flat area <br />of the tailing facility) above the historical topographical drainage divide between the East Fork <br />of the Eagle River to the southwest and Tenmile Creek to the northeast. Lake Irwin is located at <br />the base of Sheep Mountain, in an area heavily disturbed by previous mine-related activity. <br />Several intermittent and perennial channels and springs at the base of Sheep Mountain flow <br />toward Lake Irwin and maintain a relatively constant water surface area throughout the growing <br />season, and even in dry water years. The size of Lake Irwin varies throughout the year, but is