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The Bowie No. 1 Mine is located in the D seam and utilizes 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. [nventorv - The operator has identified 41 structures within the permit and adjacent areas, depicted on Map 9-7. Twenty seven (27) 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 during this permit term since mining has ceased. Should mining be resumed during this permit term, the proposed future mine plan will be reviewed as it relates to possible mine subsidence effects. The operator 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 completed a subsidence survey of hydrologic features which is described in Section 2.OS.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 hydrology of the surficial deposits. Subsidence Projections - The operator 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. [n consultation with the Division, and through the employment of Dunrud's (1976) research, the operator 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 Bowie No. 1 Mine 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). The operator has completed strain projections for the structures inventoried on Map 9-7. Strain projections have also been completed for the Pitkin Mesa and the Bowie No. 1 Mine water supply water pipelines which cross the potential subsidence zone of the life-of--mine area. The Pitkin Mesa pipeline supplies potable water to roughly 160 domestic taps. Subsidence Control Plan - The operator has proposed a subsidence control plan to prevent material damage from occurring to the renewable resource lands within Steven's Gulch and East and West Roatcap Creeks. The U.S. Bureau of Land Management Lease C-37210 also bears stipulations addressing these same concerns. The operator proposes to control subsidence within these renewable resource lands by limiting the extraction of coal beneath these potentially impacted surficial aquifers. In areas of the renewable resource lands separated from the D seam by less than 600 feet, extraction will be 37