2020-06-24_REVISION - C1981035 (2)

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ENVIRONMENTAL ASSESSMENT impoundments along unnamed intermittent drainages have been constructed to create small, seasonal ponds that may support wetlands. As discussed in Chapter 2,the existing King II Mine and the LBA reserve area are separated by The Gulch where most of the coal outcrops occur. Coal in the Project Area would be accessed from the West Mains of the King II Mine through a subsurface, low-cover crossing of The Gulch (Appendix A, Figure 2-1). In October 2018, a field survey was conducted by SME Environmental, Inc. (SME)to investigate whether any potential wetlands and/or WOTUS are present in proximity to the proposed East Alkali Gulch low- cover crossing. Prior to conducting the field survey, SME conducted a desktop study of available publications and aerial images such as: USGS 7.5' topographic quadrangles, USDI National Wetlands Inventory quadrangles, U.S. Department of Agriculture National Resource Conservation Service (NRCS) soil maps, and DigitalGlobe Aerial Imagery(July 3, 2017)from the USDA NRCS SSURGO database. Per the BLM and OSMRE's request, all NWI mapped wetlands that crossed the Gulch low-cover crossing access road or that were in the vicinity of the access road were examined. Field work was conducted by SME staff using the methodology defined in the Routine Determination procedure set forth in the U.S. Army Corps of Engineers Wetlands Delineation Manual (USACE 1987) and the Arid West Supplement (USACE 2006). Wetland boundaries were defined based on the presence of hydrophytic vegetation, hydric soils, and hydrologic indicators that under normal conditions would indicate wetland conditions. Where wetland conditions did not occur adjacent to surface water, the jurisdictional boundary was identified based on evidence of the ordinary highwater mark (USACE 2005). Additional detail can be found in Aquatic Resources Delineation Report,Alkali Gulch Low Crossing Project, LPC, CO (SME 2018). The Gulch low-cover crossing access road is located in Sections 24, 25, 26,35 and 36 of Township 35 North in Range 12 West and Sections 19 and 30 of Township 35 North in Range 11 West of the NMPM for LPC, Colorado.The East Alkali Gulch low-cover crossing survey area was defined to include the East Alkali Gulch and the surrounding forested areas approximately 1,800 ft east of De Oro Way. In general,the survey area is situated in the Middle San Juan Watershed (HUC 14080105) at approximately 7,440 ft above mean sea level. The survey area is located west of Hesperus, CO and west of the La Plata River to which The Gulch eventually drains.The total size of the survey area is 12 acres,which includes the area where the proposed East Alkali Gulch low-cover crossing would be constructed.The survey area was accessed via an unnamed dirt road off of CR 120. The USGS map shows an intermittent tributary flowing south/southwest through the survey area to the La Plata River. However, after delineation fieldwork, it has been determined that this feature is a narrow palustrine scrub-shrub (PSS) wetland. Table 3-7 lists the acreage of the wetlands/WOTUS classified in accordance with the Cowardin Classification System for wetlands and deepwater habitats (Cowardin et al. 1979).The boundaries of wetlands/WOTUS are depicted in Appendix A, Figure 3-1.Table 3-8 provides a breakdown of these resources as evaluated for a Preliminary Jurisdictional Determination from the October 2018 field survey efforts. Dunn Ranch Area Coal Lease by Application COC-78825 and Mine Plan Modification EA 3-26