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Page 6 of 7 <br />minor. Overall the surface has a more shallow and consistent grade than slopes to the <br />west and southwest. The greatest elevation difference from premining to postmining <br />north of BB road and West of 2700 road occurs on the WFC and Johnson property. The <br />postmining surface is shown to be, at a maximum, 45 feet lower than the premining <br />surface on cross - sections B -B' and D -D'. This occurred because the process of strip - <br />mining has shifted the locations of the landscape features over. The premining surface <br />had a saddle that was shifted to the south causing the postmining surface to have a <br />shallower uniform slope that drains to the north. The area to the west of cross - section D- <br />D' is also lower with a shallower uniform slope that drains to the west. The premining <br />surface in this area was dissected with small drainages. The postmining surface <br />approximates the premining surface and supports the postmining land use. <br />• OSM could not find any of the ditches referenced in permit Attachment 2.05.3(3) -1 <br />`Collection/Diversion Ditches and Culverts Design Parameters.' Specifically the ditches <br />related to the BB road, 2700 road, Benson property and Morgan property. Permit Table <br />2.05.3(3) -1 `Collection Ditch and Diversion Ditch Designs Entire Permit Area' shows <br />Ditches C -32 and C -33 with the same watershed basins (PM11B). OSM could not find <br />those ditches located on permit Map 2.05.3(3) -1 -2 `Post Mine Surface Water Hydrology <br />(Surface Water Features and Controls).' OSM also could not locate any specific <br />information regarding road ditches and drainage control for the BB road and 2700 road. <br />In pages 61 -63 of Attachment 2.05.3(3) -1 it is stated that Ditch C33 is the same as Ditch <br />C32. C33 is shown with the same design parameters as C32. Also, on permit Map <br />2.05.3(3) -1 -2, PM Basin O11B is shown with 105.1 acres and references Ditch C -32, but <br />in the design parameters of Attachment 2.05.3(3) -1, Ditch C -32 was designed with a <br />drainage area of 101.9 acres. <br />In summary, OSM has confirmed that the plans within the permit for re- establishing the <br />approximate original contour (AOC) landscape that existed prior to mining are in place and have <br />been designed in accordance with the state program regulations. Regarding the citizens <br />complaint alleging that either spoil seepage or surface drainage is reporting to the Morgan <br />property from the Benson property to the east, due to the Benson property being reclaimed to a <br />landscape higher than the original topography; OSM has determined that: 1) The approved <br />postmining topography, as shown on maps within the permit, is approved to be lower than the <br />premining topography; and 2) Drainage flow in the direction of the Morgan property from the <br />Benson property should be intercepted before it enters the Morgan property by a ditch that runs <br />along the north side of BB road. This ditch is implied by the watershed delineation on Map <br />2.05.3(3) -1 -2 `Post Mine Surface Water Hydrology (Surface Water Features and Controls) and <br />Attachment 2.05.3(3) -1 ` Collection/Diversion Ditches and Culverts Design Parameters,' but is <br />not explicitly discussed or shown in the permit text or maps. To be in full compliance with the <br />state program regulations [4.14.1(2) (f) (ii) & 4.14.2(1)J, the permit should be revised to <br />include obvious illustration of the locations of all permanent postmining ditches on Map <br />2.05.3(3)4 -2 `Post Mine Surface Water Hydrology (Surface Water Features and <br />Controls)', to clearly demonstrate that the postmining surface does have adequate drainage <br />and protection against erosion. <br />