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in Attachment 20 -D in Tab 20 of the permit. The following paragraphs highlight specific <br />landscape features that were assessed during the bond release inspection. <br />Drainage Reestablishment <br />All permanent post -mine drainage channels previously excluded from the SL -3 bond release and <br />others encompassed in the SL -4 bond release area were evaluated and inspected as part of this <br />SL -4 Phase I bond release to assess general design compliance. These postmining drainage <br />channels included PM 4 -D, portions of PM -21), portions of PM -2 and a small portions of PM- <br />2A. To the extent possible, drainage channels were reestablished to their original natural pattern to <br />minimize erosion, to conserve soil moisture, and promote vegetation. Reconstructed drainages <br />blend well with off -site drainage patterns and the drainage density is appropriate and similar to <br />adjacent undisturbed areas. Approved permanent drainages in SL -4 bond release area are <br />depicted on Figures 1(a -d) of this document, Exhibit B of the SL -4 Application "Post -mine <br />Topography and Drainage ", Permit Exhibit 20 -2 " Postmining Topography and Drainage Map ", <br />and listed in the Permit Attachment 20 -1 -1 "Post -mine Channel Design Summary ". Comparison <br />of the Post - mining Topography Map (Exhibit 20 -2) to pre- mining topography as depicted on <br />permit Exhibit 7 -6 "Drainage Basins" indicates that most pre- mining drainages were constructed <br />in their approximate original locations. A comparison of Exhibit 20 -2 from the permit with <br />Exhibit B of the SL -4 application indicates that post -mine drainages were constructed in the <br />appropriate locations with adequate drainage density. <br />Channel observations made during the June 4, 2013 inspection and the May 14 and 15, 2013 site <br />inspections are detailed in these inspection reports. Channel PM 4 -D appears to have been <br />constructed as designed, however a gully has formed in the middle of the channel. SCC was <br />unable to repair the channel prior to the approval of this phase I bond release and requested this <br />channel be removed from the phase I bond release request. Thus the Division will exclude this <br />area from approval. <br />Post mine drainage channel PM -21) was constructed slightly larger than it was designed in terms <br />of bottom width. Overall, this channel was lined with rip -rap given the slope angle of the <br />channel and appeared to be functioning. SCC has constructed this drainage in the correct <br />location. <br />The bond release parcel encompassing the Pond 016 area also encompasses a portion of post <br />mine drainage PM -2. This channel was partially relocated during the repairs that were <br />conducted around Pond 016 due to landslide activity that occurred in the spring of 2011. The <br />channel is rip- rapped and stable. The bottom width of the channel was a little larger than it was <br />designed. A small branch of the PM -2A drainage is located within the Phase I bond release <br />boundary around Pond 016 and connects to PM -2. This drainage appears stable. The Division <br />walked the edge of these drainages with a YUMA GPS unit to map the location of these <br />channels. The line feature collected with the GPS unit was downloaded and projected in <br />ArcMap® and overlaid onto a geo- referenced Exhibit 20 -2 map depicting the post mine <br />topography and drainages. It appears the Operator has constructed these drainages in the correct <br />location. Both drainages appear to have been constructed wider than the approved design which <br />Page 14 of 18 <br />