2022-01-27_PERMIT FILE - C1981019A

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 1/27/2022
• Doc Name: Performance Standards
• Section_Exhibit Name: Volume 15 Rule 4
• Media Type: D
• Archive: Yes

RULE 4 PERFORMANCE STANDARDS

Collom – Rule 4, Page 12 Revision Date: 7/28/21
Revision No.: MR-237

Groundwater Fill Piezometers - Monitoring of the West Pit fill piezometer and Section 16 Fill piezometer
have been discontinued. The West Pit Fill and West Taylor Fill piezometers will be monitored quarterly
for water levels. One additional piezometers will be installed into the toe of East Taylor Fill, once
constructed, as described in Exhibit 21 Item 1.

A future spoil water monitoring well will be drilled (and water quality monitored) as identified on Map
41B in the reclaimed Collom Pit area to monitor and measure the potential development of a spoil aquifer.
This location represents the lowest point in the Collom Pit.
4.05.14 Transfer of Wells

Please see Section 4.05.14 in Volume 1.
4.05.15 Water Rights and Replacment

Please see Section 4.05.14 in Volume 1 and Section 2.04.7(2) in Volume 15.
4.05.16 Dischrage of Water into an Underground Mine

This section is not applicable to the Collom Mine.
4.05.17 Postmining and Rehabilitation of Sediment Pond, Diversions, Impoundments, and
Treatment Facilities

Please see Section 4.05.17 in Volume 1.
4.05.18 Stream Buffer Zones

Lands within 100 feet, or greater distance if required, of a perennial, an intermittent, or an ephemeral
stream with a drainage area larger than one square mile are required to be protected under Rule 4.05.18,
unless the Division specifically authorizes surface operations within the stream buffer zone. Stream
buffer zones have been identified along Wilson Creek and Jubb Creek, as the drainage area reporting to
these streams is larger than one square mile. Colowyo will be developing the Collom Haul Road which
will be inside the stream buffer zone on both Wilson Creek and Jubb Creek.

The Collom Haul Road will cross Wilson Creek as shown on Map 25E Sheet 1. During construction
Colowyo will install a round culvert, and will employ proper best management practices (BMPs) during
the construction phase in accordance with Colowyo’s approved stormwater management plan, Section
401 certification, and US Army Corps 404 permit..

The Collom Haul Road will also cross Jubb Creek as shown on Map 25E Sheet 1. The construction of the
crossing will be similar to the Wilson Creek crossing and will utilize the same BMPs as will be installed
at the Wilson Creek crossing.

As shown on Map 25E Sheet 1, the Collom Haul Road will parallel Jubb Creek. There will be one
section of the haul road that will be slighty within 100 feet of the stream. As shown on Map 25E Sheet 1,
at approximately Station 230+00 to 250+00 there will a slight amount of disturbance within the stream
buffer zone on Jubb Creek. Proper BMPs will be employed prior to any disturbance occurring within