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The Bear Coal operation is in compliance with the provisions of this section. <br />XIV. Protection of Underground Mining <br />This section is not applicable to the Bear Coal Company permit. <br />Xv. Subsidence Control <br />A. A description of the subsidence monitoring plan for the Bear No. 3 Mine is presented in <br />Section 2.05.6 of the Bear No. 3 Mine permit application. <br />Bear Coal Company has conformed with the requirements of the permanent program <br />regulations regarding subsidence control at the Bear No. 3 Mine. No structures overlie the <br />underground workings of the Bear No. 3 Mine. Potentially affected renewable resource <br />lands are limited to the aquifers of the Barren Member of the Mesaverde and the coal <br />seams overlying the B- and C-Seams extracted in the Bear No. 3 Mine and the springs <br />located in Lone Pine Gulch. The limited area of the potentially affected aquifers which <br />occur within the permit area, and the limitation of potential effects to the down-dip, <br />near-outcrop parts of these aquifers and coal seams, reduced the possible hydrologic effects <br />of subsidence upon the aquifers and the coal seams. Bear did not mine within the angle of <br />draw of the Lone Pine springs, and additionally used 50 percent coal extraction in areas <br />adjacent to these springs. The Division does not consider the Bear No. 3 Mine a threat to <br />either structures or renewable resource lands. <br />With the submittal of Permit Revision No. 2, the Division determined that Bear Coal <br />Company should submit a list of the various structures and renewable resources within and <br />adjacent to their permit area. Bear submitted the inventory and a subsidence control plan <br />(page 2.05-63d of the permit application) to restrict mining and associated subsidence to <br />areas that are well away from structures or renewable resource lands absent additional <br />subsidence monitoring. Upon further review, the Division determined that additional <br />subsidence monitoring would be required in areas that were previously not considered as <br />renewable resources and not identified as such by the operator. These areas were the <br />Mountain Coal ventilation fan access road, an ephemeral surface tributary to Lone Pine <br />Gulch, and the area overlying panels 31-38. This additional monitoring was addressed <br />through submittal of a technical revision as required by Stipulation No. 35. <br />The canyon walls of the North Fork of the Gunnison River are covered with numerous <br />landslide deposits. These mass movement features vary in age from ancient to modern. <br />Rotational slumps, translational, earthflow and debris-flow features are present on the site. <br />A study conducted by Rocky Mountain Geotechnical of the Bear No. 3 Mine property has <br />mapped numerous mass movement features. <br />The Division was concerned about reactivation of these features by subsidence of the land <br />surface resulting from coal extraction. An extensive study by Rocky Mountain <br />Geotechnical was completed in 1986 that addressed the relationship between subsidence <br />and the potential reactivation of slide bodies above the Bear No. 3 Mine. The study <br />concluded that the general mass movement mechanism was small, shallow slope failures <br />rather than large, deep failures. The report concluded that the landslide features above the <br />Bear No. 3 Mine were unstable and that failures would occur regardless of subsidence <br />effects. No subsidence effects were expected to occur in the critical toe area of any of the <br />slide bodies. Subsidence in these areas was to be controlled by split pillar removal. <br />24