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current mine plan. Any future proposed surface disturbances associated with this lease would be <br />analyzed and approved by OSM. <br />Thirteen historic properties recommended for protection and preservation have been recorded in <br />the lease area, and are required to be avoided by all surface disturbing activities. The historic <br />properties are: 5RB 1020, 5RB 1029, 5RB 1160, 5RB 1175, 5RB6754, 5RB7286, 5RB7287, <br />5RB7289, 5RB7291, 5RB7296, 5RB7304, 5RB7305, 5RB7307, and 5MF7622. The unsuitability <br />criteria #7 applies to each of these thirteen sites that are potentially eligible for the National <br />Register of Historic Places. <br />Environmental Consequences of the Proposed Action: <br />Direct and Indirect Effects: Effects that are possible to happen to archaeological sites <br />include outright destruction of sites, artifacts, and features caused by ground disturbance. There <br />can be increased natural processes like erosion that stem from these ground disturbances. <br />Associated route construction will result in increased public access to areas where cultural <br />resources are present, if they are not gated off, causing increases in unauthorized collection and <br />vandalism. Additionally impacts to cultural resources can result from actions that alter <br />characteristics of the surrounding environment that contribute to resource significance; introduce <br />visual or audible elements out of character with the property; alter its setting; and fragment the <br />landscape in which sites are part of. <br />The Deserado Mine has done studies on subsidence at the mine, but no documented studies of its <br />effect to cultural resources can be located by the WRFO. Their mine plan includes their <br />maximum predicted subsidence from longwall mining there is 7.7 feet, and room and pillar <br />mining is 0.5 feet, as well as the subsidence control plan that they use. In 1987 and 1988 they <br />monitored the subsidence that occurred over their first longwall panel with analytical <br />photogrammetry. Their subsidence study found that the predictions had been conservative, and <br />that the subsidence was less than expected and at the maximum subsidence was 5.14 feet at their <br />test point that had the least overburden (Stinson 1988). Depth increases as the mine progresses to <br />the north, and where depth increases subsidence decreases (Deserado Mine 2011). Studies of <br />subsidence effects to cultural sites were not to be conducted as: <br />"DMG (Colorado Division of Minerals and Geology) and OSM (Office of Surface <br />Mining) have determined that the best mitigation for archaeological sites subject to <br />potential subsidence was to limit access to the area and limit access to the location <br />information. It was determined that subsidence itself did not produce a detrimental <br />impact to the cultural resources. Subsidence is expected to produce no long term impacts <br />on these sites. (Deserado Mine 2011)" <br />However, as generally accepted knowledge in the archaeological community, underground coal <br />mining and subsequent subsidence can cause surface disruption and direct impacts to both <br />known and unidentified cultural resources. Sites most sensitive to the effects of subsidence <br />include rock shelter and rock art sites located on or beneath rock outcrops. A recent, local <br />example is the collapse and destruction of the eligible Red Army Rockshelter site (5RT345) in <br />the Little Snake Field Office (LSFO) area, after subsidence of an underground coal mine <br />occurred (per conversation with LSFO Archaeologist Ethan Morton). Standing prehistoric and <br />DOI- BLM -CO- 110- 2012- 0023 -EA 59 <br />