2018-07-09_PERMIT FILE - C1981019A ‎(58)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 7/9/2018
• Section_Exhibit Name: 2.04.7 Hydrology Information
• Media Type: D
• Archive: Yes

RULE 2 PERMITS
state, and it is replaced in an unconsolidated condition. While it is impossible for the mining and
reclamation operation to reconstruct the stabilizing affects of these drainages in bedrock, it is possible and
desirable to recreate the stabilizing affects of the rock protection. This method has been elected to armor
and stabilize the permanent stream channels constructed or to be constructed at the Colowyo Mine site. A
summary of these channels is presented below, and the location of the areas to receive rock riprap
protection are shown on Map 12- Hydrology, South.
Southwest Tributary to Streeter
South East Tributary to
Streeter
Streeter Gulch
Gulch A
Section 11 Ditch
Prospect
Final East Pit
Section 16 Fill
South Connection
West Pit
Taylor Tributary
West Pit Fill
Permanent Drainage Channels
Total
Length of Drainage
Channels - Feet
Unprotected
Rock Protected
Total
0
3,200
3,200
2,500
4,000
6,500
5,700
13,000
18,700
0
7,500
7,500
0
1,000
1,000
1,400
2,200
3,600
1,200
4,600
5,800
0
900
900
0
1,200
1,200
2,700
14,300
17,000
2,500
11,500
14,000
1,300
5,000
6,300
17,300
68,400
85,700
This rock riprap protection in the channels on steep slopes will pass the intermittent low flows normally
found in the area and approximate the original cascading flows while protecting the channel during the
infrequent high flows the design event is likely to produce. Given time, vegetation will encroach portions
of these channels, debris will accumulate and the stream will again reach a state of dynamic equilibrium.
Calculation for rock riprap sizing and gradation are found in Exhibit 7.
Rule 2 Pen -nits 2.04.7-29 Revision Date: 4/7/17
Revision No.: RN -07