2014-07-03_PERMIT FILE - C1981035A (5)

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f ,141 :EelOR Prior to the field surveys, U.S. Geological Survey topographic maps were reviewed to determine the location, elevation, soil types, and potential habitat types within the project areas. Wetland and drainage data were evaluated using National Hydrography Dataset maps and geographic information system (GIS) data. SWCA biologist Eilene Lyon conducted the surveys on February 26 and 27, 2014. Coordinates provided by GCC were used to locate the proposed drill hole sites. The field surveys consisted of a pedestrian survey of the project areas to assess general vegetation and habitat as they relate to Colorado special status species. All plant species were identified, with the exception of some dormant, dead, or newly emergent plants. A list of wildlife species and sign observed was compiled. U.S. Fish and Wildlife Service (USFWS) and Colorado Parks and Wildlife (CPW) lists of threatened, endangered, proposed, and candidate species, as well as species of special concern, for La Plata County were obtained for review prior to the site visit. RESULTS General Characteristics The average elevation of the nine project areas is 2,311 in (7,583 feet) above mean sea level, ranging from 2,228 to 2,368 in (7,310 -7,768 feet). According to the Western Regional Climate Center' for the period of 1996 to 2008, normal annual precipitation for the general project area averaged 32.08 cm (12.63 inches), based on information for Durango, Colorado. The precipitation falls close to evenly throughout the year, with the exception of the driest months of May and June. Average annual snowfall was 178.6 cm (70.3 inches) based on data from 1948 to 1991. The average annual temperature for the area is 8.17°C (46.7 °F), with an average annual maximum temperature of 17.0 °C (62.67) and an average annual minimum temperature of - 0.67°C (30.8 °F).2 The weather during the surveys was sunny and cool with a slight breeze on the first day, and overcast with nearby thunderstorms on the second day. Noise from mining activity was low to moderately high, depending on the slope of each site. The noise level was highest at CO- 14 -03. Photographs of the project areas are at the end of this technical memorandum. Soils Soils in five of the project areas are Pulpit loam, which is found on mesas with slopes ranging from 3% to 12 %. Pulpit loam is a well- drained sandy to clay or silty clay loam derived from loess. It has a typical profile of loam to clay loam and silty clay loam to fine sandy loam, 0 to 88.9 cm (0-35 inches). Soils in four of the project areas are Lazear -Rock outcrop complex, which is found on side slopes of mesas and land breaks with 12% to 65% slopes. This complex is a well- drained, very stony to clay loam residuum or slope alluvium derived from sandstone and shale. The profile of Lazear -Rock outcrop complex is very stony loam to stony loam, loam and clay loam, 0 to 38.1 cm (0-15 inches). One other soil type is present at one project site: Archuleta- Sanchez complex. This complex is found on mountainsides, hillsides, and ridges with 12% to 65% slopes. This complex is a well- drained loam to gravelly clay loam with interbedded sandstone and shale. The profile of Archuleta- Sanchez complex is loam, clay loam, loam to gravelly clay loam, 0 to 30.48 cm (0-12 inches).' Table 1 lists the soils at each of the well pad sites. Some cryptobiotic soils were found in the CO -14 -02 and CO -14 -09 project areas. ' Western Regional Climate Center. 2014. Colorado Climate Summaries. Available at: http:// www .wrec.dri.edu/COMPARATIVE.html and http:// www. wrcc.dri.edu/summaryAcdus08.html. Accessed March 2014. Z Ibid. 3 Natural Resources Conservation Service. 2014. Web Soil Survey. Available at: http: / /websoilsurvey.nres. usda.gov /app/WebSoilSurvey.aspx. Accessed February 2014. Technical Memorandum / SWCA Project No. 28487 April 11, 2014 King II Appendix 8 (5 )