2013-02-22_PERMIT FILE - C1981019A ‎(3)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 2/22/2013
• Section_Exhibit Name: Rule 4 Performance Standards -ST
• Media Type: D
• Archive: Yes

RULE 4 PERFORMA STANDARDS
and results of the current monitoring program are included in the Annual Reports for 1983 through 1990.
In addition, Section 2.05.4 and 2.05.5 details the specific mining and reclamation techniques which
Colowyo will implement to minimize changes to the hydrologic balance.
The post- mining land use as described in Section 2.05.5 will be rangeland. Changes in the hydrologic
balance will be minimized so that the post- mining land use will not be adversely affected.
Water quality standards and effluent limitations at the existing mining operation are regulated by the U. S.
Environmental Protection Agency and the Colorado Department of Public Health and Environment under
the terms of an NPDES Permit, (See Exhibit 7, Hydrological Information), and by the Coal Regulations
of the Colorado Mined Land Reclamation Board. The applicable effluent limitations will be met by using
treatment methods that will include prompt revegetation, minimizing disturbed areas, sediment retention,
use of contour furrows, terraces, sediment ponds and, if necessary, strategically placed energy dissipaters,
such as riprap, check dams, mulches, filters and dugouts. Water quality control measures are discussed in
detail under Section 2.05.4 and 2.05.6.
Where practicable, diversion methods will be used to change the flow of water from undisturbed areas so
as to bypass the disturbed areas rather than using treatment facilities. The principal technique to be used
for this purpose will be diversion ditches. These diversion ditches are located on Maps 11 and 12 and
discussed in detail under Section 2.05.6. Their design is specified in Exhibit 7, Hydrological Information.
No acid - forming materials are present in the area to be mined which would require selective placement
and sealing of overburden (Exhibit 6). The chemical characteristics of the overburden is presented under
Section 2.04.6. The overburden sampling program is presented under Section 2.05. Results of the current
overburden sampling program are presented in the Annual Reclamation and Hydrology Reports beginning
in 1983 to the present.
As discussed in Section 2.05.4, Colowyo will use various surface manipulation techniques on the topsoil
after its redistribution as one method to prevent excessive wind or water erosion.
No special treatment of coal processing waste is necessary since none will be produced. See Section 4.10
and 4.11.
Colowyo plans to have all surface runoff from the disturbed areas pass through sedimentation ponds.
Sedimentation ponds are discussed in detail under Section 4.05.6, and their locations are shown
graphically on the mine plan map (Map 23A).
Colowyo employs various methods to manage water which periodically collects internal to the mining
operation and does not reach sedimentation ponds. Various sumps, ditches, pumps, hoses and pipes, etc.
will be employed to control water within pits and/or route water between pits. The ultimate destination of
such water will be for operation's use (i.e. dust control), evaporation, or seepage into the backfilled spoil
areas.
In addition to the mining, reclamation, and treatment methods described and referenced in this Section,
further protection of the hydrologic balance will be established by an on -going plan for monitoring
potential changes in surface water quality and quantity and groundwater quality. This monitoring plan is
described under Section 4.05.13 and the monitoring locations are graphically shown on Map 10A. Excess
spoil valley fill areas are located up -dip from mining and reclamation areas and periodic monitoring for
seeps and springs and periodic monitoring of piezometer wells will detect the formation of spoil springs.
South Taylor /Lower Wilson — Rule 4, Page 4 Revision Date: 07/27/09
Revision No.: TR -76