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-57- CWI proposes to mine the "D" seam, utilizing conventional room and pillar methodology. The applicant has completed the required inventory of structures and renewable resource lands, a projection of probable subsidence, and developed a subsidence control plan and an appropriate accompanying subsidence monitoring plan. Inventory CWI has identified 29 structures within the permit and adjacent areas, depicted on Map 9-7. Nineteen (19) of these structures were inventoried within the permit area, as well as two water pipelines and an all-weather gravel road within Steven's Gulch. No inventoried structures will be affected by mining operations proposed during this permit term. CWI has also identified several alluvial/colluvial surficial deposits which constitute renewable resource lands within the revised permit area. surficial deposits have been identified within Steven's Gulch, East Roatcap Creek, and in the area of the Morrell Cow Camp. fie applicant completed a subsidence survey of hydrologic features which is described in Section 2.05.b(b)(e) Additional shallow alluvial monitoring wells were installed within the alluvial-colluvial deposits for the purposes of monitoring potential effects of subsidence upon the i~ydrology of the surficial deposits. Subsidence Projections CWI retained Geo-Hydro Consultants, Inc., to complete a technical projection of subsidence expected within the revised permit area. Atypical subsidence profile is graphically depicted on Plate 11 of the subsidence study in Volume 3. Vertical subsidence is projected to reach a maximum of approximately six feet. In consultation with the Division, and through the employment of Dunrud's (1976) research, CWI estimates the conservative angle-of-draw to be 20.5 degrees from vertical. The technical projections included in the subsidence study conform with the prudent state-of-the-art of subsidence projection. Subsidence monitoring has been conducted within the Orchard Ya11ey permit area, in compliance with the originally approved permit. The data collected to date corresponds with the technical projections for vertical subsidence and draw angle (See Table 8, Volume 3 and annual subsidence reports). CWI has completed strain projections for the structures inventoried on Map 9-7. Strain projections have also been completed for the Pitkin Mesa and CWI water supply water pipelines which cross the potential subsidence zone of the life-of arsine area. The Pitkin Mesa pipeline supplies potable water to roughly 160 domestic taps. Subsidence Control Plan CWI has proposed a subsidence control plan to prevent material damage from occurring to the renewable resource lands within Steven's Gulch and East Roatcap Creek. fie U. S. Bureau of Land Management lease C-37210 also bears stipulations addressing these same concerns.