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By exception, the Applicant is in compliance with this rule. No reclaimed area of the Permit is <br />cropland. <br />1S. Rule 4.20.3(1) Surface Owner Protection (Subsidence) <br />Each person who conducts underground mining activities shall adopt all measures of the subsidence <br />control plan approved by the Division to reduce the likelihood of subsidence, [o prevent subsidence <br />from causing material damage or reducing the value or reasonably foreseeable use of surface lands, <br />and to mitigate the effects of any such damage or reduction which may occur. <br />The Division may release the bond or reclamation liability for surface areas overlying underground <br />workings only after all mining in the area is completed and the major subsidence effects, if any, have <br />been manifested, Division policy is that the liability period is a minimum of three years after mining <br />for areas of extraction. (CMLRD Policy Memorandum, "Release of Liability of Areas Overlying <br />Underground Coal Mine Workings", April 13, 1987.) <br />Structures and features within the original mine plan area included State Highway 13, Curtis Creek, <br />Jensen Ranch buildings, reservoirs, ponds and dams, a natural gas pipeline, power lines, <br />archaeological sites, and structures owned by (the then) Northern Coal Company (Permit, Page S-1). <br />These structures and features are located on Exhibit S-1 of the Permit (Subsidence Survey Map, <br />3/25/80). Coordination had been completed with the Colorado State Department of Highways (Permit, <br />Page S-17a, Highway Department letter, October 28, 1980), Western Slope Gas Company (Public <br />Service Company of Colorado, Permit, Page S-19, Western letter of April 14, 1980), and White River <br />Electric Association, Inc (Permit, Page S-21, White River Electric Association letter of April 3, 1980). <br />No secondary mining was to be performed beneath archaeological sites and therefore should not <br />undergo any subsidence (Permit, Page 5-20, Paragraph 5.7). The Applicant satisfied concerns for <br />mining under all the structures and features (Permit, Pages S-16 through 5-26). Structures and features <br />actually undermined were State Highway 13, Curtis Creek, the electric power lines, and facilities <br />owned by Enron Coal Company (Documents 25 and 26, both hand delivered to the Division on January <br />20, 1998, as depicting the maximum extent of underground mining). The Permit approved only <br />advance room and pillar mining under the Highway and Curtis Creek (and due to close proximity, the <br />power lines). No secondary mining (retreat room and pillar or longwall) under these resources, or <br />within an angle of draw that may have an impact upon the highway, was permitted (Permit, Page S- <br />16). Although not undermined, advance room and pillar mining (a gateway) approached to within <br />approximately 100 feet (horizontal distance) of the natural gas pipeline, at a depth of approximately <br />300 feet of overburden (Document 25, posted as 12/31/80)(five gateways, approximately 20 feet wide, <br />on 80- to 90-foot centers, approached the natural gas pipeline, and terminated approximately 100, 130, <br />250, 300, and 300 feet from the pipeline). <br />Only records of subsidence monitoring at the Rienau ~/ 2 Mine were found in the Permit files. <br />"Subsidence monitoring showed no evidence of surface subsidence due to past or on-going operations." <br />was reported in an Office of Area Mining Supervisor, CRMA, memorandum of November 14, 1979 <br />{Document 27). A conclusion within a Curtis Creek subsidence report (copies of subsidence reports <br />28 20 January 1998 <br />