2018-10-19_REVISION - M1980244

• Permit No: M1980244
• IBM Index Class Name: Revision
• Doc Date: 10/19/2018
• Doc Name: Adequacy Review Response
• From: CC&V
• To: DRMS
• Type & Sequence: TR101
• Email Name: TC1
• Media Type: D
• Archive: No

Kn i ht Piesold Table3.1
9Cripple Creek and Victor Gold Mining Co.(Newmont)
C O N S U L T I N G Cripple Creek and Victor Mine
Stormwater Management Plan Evaluation
Summary of Modified SWMP Evaluation Findings
Impoundment Spillway Inflow Diversion Channel
Required Weir Required Chute As-built
Required Volume: As-built Weir As-built Chute As-built Riprap Required Riprap Required Peak As-built Riprap Required Riprap
EMP As-built Volume U SpillwayPeak Flow: Peak Flow:Upgrades Upgrades Channel Flow Upgrades
2x 10yr/24hr RunoffFlow Capacity Flow Capacity Stability Stability Flow: 100yr/24hr Stability Stability
(fts) ( 3) required? exists? ) 100yr/24hr ( ) 100yr/24hr y y required? Exists? Capacity ( ) y y required?
ft (cfs (cfs) cfs (cfs) Factor of Safety Factor of Safety (cfs) cfs Factor of Safety Factor of Safet
• 126,587 Yes Yes170 39 No NA NA NA NA NA
• chute NA1.2 Yes
560,736 501,995 NoYes 0 �241.3 12 300 131 0
8c 163,690 111,433(') No Yes 42 29 153 29 1.4 1.2 No No NA NA NA NA NA
9a-d(combined) 270,351 99,863(61 No •. • No NA NA NA NA NA
11 286,146 214,967(7� No(') No NA NA NA NA NA NA No No NA NA NA NA NA
250 57
16 167,265 21.930 No 25 4 111 36 • - `. 2.7 1.2 -
34 30 50 1.9 1.2 111 36 •
17, 17a, 17b 526,446 193,518 No
(combined) • 30 10 65 4.6 1.2 Yes 39 9 4.1 1.2 No
• • No NA NA NA 18 199,631 157,385 No • - • 1033120 320,145 67,494 No21 89,235 66,551 No • No NA NA NAONA
NA NA
.•: • • No NA NA NA NA NA
• •- .- No NA NA NA NA NA NA No No NA NA NA NA NA
Notes:
1. Red shading denotes structures that require upgrades.
2.Green shading denotes structures that do not require upgrades.
3. EMP 6:The existing spillway chute appears to lose containment near the outlet. Upgrades will be required regardless to extend the chute to the second,expanded EMP 6 pond.A second spillway design is included to discharge from the second EMP 6 pond to the environment.
4. EMP 8a:A new diversion channel (DC-EMP8a)was designed to EMP 8a that will divert part of the existing EMP 9a-d contributing area.The required volume accounts for the new diversion channel(DC-EMP8a).
5. EMP 8c:The required volume accounts for the reduced area due to the Squaw Gulch VLF 2 expansion.
6. EMP 9a-d:The required volume accounts for the reduced area due to the new diversion channel (DC-EMP8a)that will divert part of the existing EMP 9a-d contributing area to EMP 8a. Four(4)spillways designs are required.
7. EMP 11: Reclassified as a'non-EMP'structure, per CC&V.The as-built volume is sufficient to store the runoff volume from a single 10-year/24-hour storm event,as shown in the'Required Volume'column for this EMP. Upgrades(including spillway)and further analyses not required.