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-56- The proposed operation is in compliance. XX. SEALING OF DRILLED HOLES AND UNDERGROUND OPENINGS (2.05.4(2)(8), All concerns regarding sealing of drilled holes and underground openings have been resolved, and the proposed operation is in compliance. XXI. SUBSIDENCE (2.05.6(6), 4.20) 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 appropriate accompanying subsidence monitoring plan. Inventory CWI has identified 29 structures within the permit and adjacent areas, depicted on Map 9-7. 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. One of these inventoried structures will be affected by mining operations proposed during the initial 5-year permit term. That structure (No. 27 on Map 9-7) is an "unliveable, dilapidated ruin". 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. The applicant has committed, on pages 156A and 157 of Section 2.05.6(6) of the application, to the completion of additional hydrologic investigations within these surficial deposits during the summer of 1985. Asa portion of these investigations, additional shallow alluvial monitoring wells will be installed within these deposits for the purposes of monitoring potential effects of subsidence upon the hydrology of these surficial deposits. Subsidence Projections CWI retained Geo-Hydro Consultants, Inc., to complete a technical projection of subsidence expected within the revised permit area. The projected subsidence is graphically depicted on Figure 14 of the Appendix to Volume 3 entitled "Report - Subsidence Study Proposed Long-term Lease Area Orchard Valley Coal Mine for Colorado Westmoreland, Inc.". Vertical subsidence is projected to reach a maximum of approximately six feet. The technical projections included within this appendix conform with the prudent state-of-the-art of subsidence projection. Subsidence monitoring has been conducted within the Orchard Valley permit area, in com liance with the originally approved permit. To date, the results of the monit ring program have been limited. However, the data collected to date corresp nds with the technical projections for anticipated subsidence (See Table 8, Volume 3).