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Included in the post -mine regrading operation was the construction of small swales and hummocks <br />to minimize erosion and to conserve soil moisture and to promote revegetation. These features were <br />constructed on steeper slopes in the reclaimed area. <br />SCC generated topographic maps, using photogrammetric methods, of backfilled and regraded areas <br />on an annual basis. These maps were submitted to the Division each year in the Annual <br />Reclamation Report. The maps were used to determine whether regraded areas were consistent <br />with the approved postmining topography. <br />Each year SCC also submits a Rill and Gully Survey. This annual report is produced by <br />inventorying erosional features on the hillslopes and drainage channels where additional repairs and <br />maintenance work are identified. The 2011 and 2012 survey maps were referred to during the bond <br />release inspection. <br />Drainage reconstruction <br />The approved drainage reestablishment consisted of the design and construction of permanent <br />postmining drainage channels. The post -mine channels are shown on Figures 1(a -d) of this <br />document. Post -mine channels are designed and certified to safely convey the peak discharge from <br />the 10 -year, 24 -hour storm event in accordance with Rule 4.05.3 and do not require as -built <br />certifications. Certified designs for the post -mine channels were approved prior to the bond release <br />application and are provided in Tab 20 Attachment 20 -1 of the permit. The approved Post - Mining <br />Topography Map, Exhibit 20 -2 shows the location of the approved post -mine channels. Exhibit <br />B of the SL -4 application, "Post -mine topography and Drainage" shows the completed drainage <br />channels. <br />In the original permit area Post -mine Channel 005 Gulch, and its' tributary 005 -E1, flow to Pond <br />005 which discharges through an unnamed drainage into Dry Creek. Post -mine Channel 006 <br />Gulch, and its' tributaries: 006 -NE1, 006 -NE2, 006 -NE3, 006 -E1, and 006 -E2 flow to Pond 006 <br />which discharges into Hubberson Gulch which also flows into Dry Creek. Several other <br />designed permanent tributary drainages were approved through revisions to the permit, including <br />005 -W1, 006 -S1, 006 -NE3, and 006 -NE4. In the South Extension Area, postmining drainage <br />channels PM -2 and PM -3 flow into Pond 016, which discharges into an unnamed tributary of <br />Hubberson Gulch and eventually into Dry Creek. Postmining drainage channel PM-IA flows <br />into Pond 017 which also flows into Hubberson Gulch and then into Dry Creek. Additional <br />tributary drainage channels have been "field fit" in accordance with provisions of the approved <br />rill and gully repair plan, in locations where concentrated flows on the reclaimed landscape <br />resulted in channel formation. <br />Facilities <br />The final reclamation plan for the Seneca II -W Mine includes retention of numerous permanent <br />facilities including access and light use roads, an electric substation and powerline, and various <br />fences associated with grazing management, property boundaries, and shrub plots. <br />Documentation to support retention of all approved facilities has been provided within Tab 20 <br />Page 11 of 18 <br />