2018-09-04_GENERAL DOCUMENTS - C1980007

• Permit No: C1980007
• IBM Index Class Name: General Documents
• Doc Date: 9/4/2018
• Doc Name: Proposed Decision and Findings of Compliance
• From: DRMS
• To: CAM Mining, LLC
• Permit Index Doc Type: Findings
• Email Name: LDS
• Media Type: D
• Archive: No

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3. The Division proposes to exempt specific small areas from the use of sediment
ponds for the following reasons: each area is of limited size, ponds and
treatment facilities are not necessary for drainage in each area to meet the
effluent limitations of Rule 4.05.2 and applicable State and Federal water
quality standards for receiving streams, and no mixing of surface drainage with
a discharge from underground workings will occur. The following areas are
exempted: the Sylvester Gulch fan site, an area located downstream from the
MB-5E pond, the 1.2 million gallon water tank, the area surrounding the raw
water intake gallery, the Shaft 3 area, the drill pads utilized at the “thermal
event” area, the drill pads at MVBs, the sites of the former Lone Pine
substation and Lone Pine ventilation fan and associated facilities, the corrals
laydown/staging area, and the Deer Creek Shaft area [4.05.2(3)(b)(i)].

B. Diversions and Conveyance of Overland Flow

1. Sediment control ditches have been designed and constructed in compliance
with Rule 4.05.3. Locations are shown on the Map 54 series, and designs can
be found in Exhibit 66. A summary of the designs can be found on Table 44
in Exhibit 66 of the PAP [4.05.3(2)].

C. Stream Channel Diversions

1. The West Elk Mine does not propose any stream channel diversions;
therefore, this section is not applicable.

D. Sedimentation Ponds

1. Mountain Coal Company has constructed six sediment ponds and two
freshwater ponds. The ponds have been designed, constructed and maintained
in accordance with the requirements of 4.05.6 and 4.05.9. The location of
these ponds can be found on the Map 54 series. The designs of the ponds can
be found in Exhibit 66. The ponds are located as near as practical to the
disturbed area and are not located within perennial streams according to
4.05.6(1)(b).

E. Acid-forming and Toxic-forming Spoil

1. Underground development waste from underground workings at the West Elk
Mine is handled as coal mine waste and placed on the Lower Refuse Pile
(LRP), Refuse Pile Expansion (RPE) and Refuse Pile Expansion East (RPEE).
No acid-forming or toxic-forming materials are present in the waste in
quantities significant enough to affect groundwater quality. Therefore, special
handling is not required for these materials [4.05.8(3)]. An Upper Refuse
Disposal Area has also been approved for construction, but has not been built.
MCC has verbally indicated this pile will not be needed. Stipulation #7
requires MCC to complete a geotechnical investigation prior to constructing
the Upper Refuse Disposal Area.