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Inventory <br />The operator has identified 29 structures within the permit and <br />adjacent areas, depicted on Map 9-7. Nineteen (19> of these <br />structures were inventoried within the permit area, as well as two <br />water pipelines and an all-weather gravel road within Steven's Gulch. <br />No inventoried structures will be affected by mining operations <br />proposed during this permit term. Stipulation No. 42 of this permit <br />renewal requires the operator to submit waivers for any "occupied <br />dwellings within 100 feet of the permit area." The operator has also <br />identified several alluvial/colluvial surficial deposits which <br />constitute renewable resource lands within the revised permit area. <br />surficial deposits have been identified within Steven's Gulch, East <br />Roatcap Creek, and in the area of the Morrell Cow Camp. The applicant <br />completed a subsidence survey of hydrologic features which is <br />described in Section 2.05.b(b)(e> Additional shallow alluvial <br />monitoring wells sere installed within the alluvial/colluvial deposits <br />for the purposes of monitoring potential effects. of subsidence upon <br />the hydrology of the surficial deposits. <br />Subsidence Protections - <br />The operator retained Geo-Hydro Consultants, Inc. to complete a <br />technical projection of subsidence expected within the revised permit <br />area. Atypical subsidence profile is graphically depicted on Plate <br />11 of the subsidence study in Volume 3. Vertical subsidence is <br />projected to reach a maximum of approximately six feet. In <br />consultation with the Division, and through the employment of Dunrud's <br />(1976) research, the operator estimates the conservative angle-of-draw <br />to be 20.5 degrees from vertical. The technical projections included <br />in the subsidence study conform with the prudent state-of-the-art of <br />subsidence projection. <br />Subsidence monitoring has been conducted within the Orchard Valley <br />permit area, in compliance with the originally approved permit. The <br />data collected to date corresponds with the technical projections for <br />vertical subsidence and draw angle (See Table 8, Volume 3 and annual <br />subsidence reports). <br />The operator has completed strain projections for the structures <br />inventoried on Map 9-7. Strain projections have also been completed <br />for the Pitkin Mesa and Orchard Valley Mine water supply water <br />pipelines which cross the potential subsidence zone of the <br />life-of-mine area. The Pitkin Mesa pipeline supplies potable water to <br />roughly 160 domestic taps. <br />Subsidence Control Plan - <br />The operator has proposed a subsidence control plan to prevent <br />material damage from occurring to the renewable resource lands within <br />Steven's Gulch and East and West Roatcap Creeks. The U.S. Bureau of <br />Land Management Lease C-37210 also bears stipulations addressing these <br />same concerns. <br />-40- <br />