_INSPECTION - C1982057 ‎(5)‎

• Permit No: C1982057
• IBM Index Class Name: Inspection
• Doc Name: Inspection Report
• From: DRMS
• To: Seneca Coal Company
• Inspection Date: 5/16/2011
• Email Name: SLB
• Email Name: SB1
• Media Type: D
• Archive: No

May 16, 2011 C-1982-0571Seneca II-W Mine SLB
The discharge riser(primary spillway)to Pond 016A has been damaged by ice on the pond surface during the
winter. The riser was torn at the point where the vertical and horizontal pipes meet, causing the pond to dewater at
the level of the horizontal pipe instead of the riser elevation. All discharge from the pond was flowing to Pond
016. There were two large cracks in the embankment of Pond 016A,having been caused by either the ground
movement in the area or the damaged spillway. There were also cracks between the Pond 016A outfall and the
inlet slope of Pond 016. Since Pond 016A had been dewatered by the damaged primary spillway,the risk of
embankment failure was lessened. The operator should not allow the water in the pond to rise above the damaged
spillway elevation,and should immediately pump the water out of the pond in the event that the level rises. The
operator has proposed to remove Pond 016A as part of the slide remediation plan currently under review(TR-73).
Since the pond will be removed, repairs to the pond will not be required at this time. Should the pond not be
completely dewatered and removed within 90 days of this inspection, repairs will be required.
Pond 016 was discharging very turbid water. A sample for settleable solids was taken in an Imhoff cone; after one
hour,there was a barely detectable amount of solids in the bottom of the cone,well below the 0.5 mlll standard.
The embankment of the pond was stable and well vegetated,and the outfall areas of both spillways were stable.
Postmining drainage channels that were accessible were in good condition and functioning as designed. All of the
major drainage channels were flowing at or near capacity due to the high snowpack and recent rains.
ROADS—Rule 4.03
Construction 4.03.1(3)14.03.2(3)
,iDrainage 4.03.1(4)14.03.2(4)
'Surfacing and Maintenance4.03.1(5)and(6)14.03.2(5)and(6)
Reclamation 4.03.1(7)14.03.2(7):
A slide had occurred along the Mine Entrance Haul Road(MEHR)on the south side of the road. The slide is
approximately 200' in length, and originated at the top of the road embankment. The approximate location of the
slide is shown as"Area 1"in Figure 1 of this document. The movement of the embankment resulted in fill
material being pushed into and constricting the flow of Dry Creek. Severe erosion of the sidewalls has occurred in
the Dry Creek channel as a result of the constricted flow,and sedimentation has occurred offsite where material
from the road fill was washed into Dry Creek. An approximately 25 l.f. long section of the toe approximately 3'
thick had entered into and partially blocked the river channel. As a result, the Division issued Notice of Violation
No. CV2011-001 for failure to ensure that"construction,maintenance,and post-mining conditions of haul roads
into and across the site of operations will control or prevent erosion and siltation,pollution of air or water,and
damage to public or private property",as required by Rule 4.03.1(1)(a),and failure to ensure that haul roads do not
cause"additional contributions of suspended solids to strea nflow or to runoff outside the permit area"as required
by Rule 4.03.1(1)(b). An excavator was working during the inspection to pull the material out of the creek bed,
and a scraper and dozer were moving the material to the opposite side of the road. In addition to remediation of
the slide area, the operator was working to narrow the MEHR to the approved post-mining configuration.
Number of Partial Inspection this Fiscal Year: 9
Number of Complete Inspections this Fiscal Year: 3
Page 3 of 15