PERMFILE135522

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: EXHIBIT 7 Archived Section 2 Part 2
• Media Type: D
• Archive: Yes

Mr. Richard Atkinson
• May 14, 1981
Page Five
The Taylor Gulch Pond and Gulch A have been revised to accommodate the
revised sediment volumes resulting from revised sediment delivery ratios and
revised CS factors.
5. Working area percolation pond: This pond is a component in the sanitary
waste disposal system and as such is not connected with storm drainage or the
sedimentation ponds.
b. Drainage from disturbed areas: The areas described in this point are drained
to t e Streeter Gu c and Gulch A detention ponds by the use of berm ditches,
terrace or contour ditches and the East Collection Ditch. In the area near
Streeter Gulch berm ditches at vertical intervals of 100' are employed to carry
the drainage along the berms in a northernly and westernly direction to the
Streeter Gulch channel. In the Section II fill either terrace ditches or contour
ditches will be used to conduct drainage to the Gulch A south ditch (Drainage
No. 5) and thence to Gulch A detention pond. A small area in the vicinity of
the Gulch A north ditch (Drainage No. 4) will be also conducted along terrace
ditches or contour ditches to the Gulch A north ditch and thence into the Gulch A
detention pond. The Eastside collection ditch, a portion of which is constructed
• and operating in Section 2, collects runoff from the fill areas below the last berm
and from construction roads and conducts this runoff to the 6900 berm of the
Streeter Gulch fill. As this ditch is extended with the mine progression into
Section II a portion of the ditch will discharge flow into Gulch A drainage system
and thence into the Gulch A sedimentation pond.
7, Section II Permanent Diversions: The Adequacy Review inquires about the design
of diversions to a located in conjunction with the Section II fill. The original design
of these diversions was a single diversion channel located along the south boundary
of the Section II fill. Data and sketch of this channel are given in Table 1 and
Figure 1 of Exhibit 7 to the Permit Application. The final post mining topography
as shown on Map 19 of the Permit Application portrays a minor modification to the
original design consisting of connecting the beginning of the ditch to the Streeter
Gulch Drainage (Drainage No. 3), thus restoring the drainage pattern closer to
pre-mining drainage pattern. This results in a smaller diversion that the Diversion
No. 2 to Prospect Gulch listed in Table 1 of Exhibit 7, for which the design section
should suffice.
8. Stock Water Ponds: The Adequacy Review requires compliance with applicable
ru es and standards. All engineering for these ponds will be in compliance with
the required standards.
2.05.4 (2)(C) 4.14 Backfilling and Grading
. 5. Stream Channel Reconstruction: The Adequacy Review requested plans for all
stream c annel reconstruction. The design data for all stream channel reconstruction
and supplementary ditches is given on Table 1 of Exhibit 7, sketches of the ditches