2024-08-22_PERMIT FILE - C1981019A

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 8/22/2024
• Doc Name: Volume 1 Rule 4
• Section_Exhibit Name: Rule 4 Performance Standards
• Media Type: D
• Archive: Yes

RULE 4 PERFORMANCE STANDARDS

Rule 4 Performance Standards 4-30 Revision Date: 6/24/24
Revision No.: MR-255
4.11.3 Return to Underground Workings

(Not Applicable)

4.11.4 Disposal of Noncoal Waste

Noncoal, nonhazardous solid waste, such as garbage, used tires, etc., is stored in a controlled
manner around the operation in various waste receptacles and waste locations. Periodically the
waste is disposed of in the backfill area of the pit and covered with a minimum of two feet of
overburden material. No waste is allowed on the bottom of the backfill area or below the
anticipated groundwater level of backfilled areas.

Facility structures including but not limited to concrete foundation will be demolished in-place
and covered with a minimum of six feet of suitable material. The area will be regraded to blend
with the surrounding topography followed by topsoil and seeding as described in the reclamation
plan. All demolition materials related to sedimentation ponds will be placed within the ponds a
covered with a minimum of six feet of suitable material or transported to the pit area during the
reclamation process. Noncoal, nonhazardous solid waste is regulated under the Moffat County
Special Use permit identified in Section 2.03.10.

Nonhazardous used oil and grease, flammable liquids, etc. are stored in a tankfarm facility located
near the shop facilities.

Colowyo’s status as a conditionally exempt small quantity generator of hazardous materials
essentially indicates that Colowyo generates negligible amounts of hazardous waste. The limited
amount of hazardous waste is handled according to applicable State and Federal requirements.

Waste water from toilets, sinks, and showers will be disposed of by means of septic tanks,
underground leach fields and evaporation ponds.

Portable self-contained toilets will be located around the operation. These portable toilets will be
serviced periodically and the waste hauled from the mine for disposal.

4.11.5 Dams and Embankments

(Not Applicable)

4.12 SLIDES AND OTHER DAMAGE

Because of the mining technique used at the Colowyo operation and the inherent nature of the coal
geology, no natural barriers will be necessary.

At any time a slide occurs within the permit area which may have a potential adverse affect on
public property, health, safety, or the environment, Colowyo will notify the Division or other
appropriate governmental agencies and comply with any remedial measures necessary.