2010-11-17_INSPECTION - C1981019

• Permit No: C1981019
• IBM Index Class Name: INSPECTION
• Doc Date: 11/17/2010
• Doc Name: Inspection Report
• Inspection Date: 11/3/2010
• Email Name: JRS
• Media Type: D
• Archive: No

November 3, 2010 C-1981-019/Colowyo Coal Mine JRZZ?7
West Pits, Colowyo has also regraded approximately 17 acres in a wedge along the old East Pit reclamation in the
Streeter watershed and the old R3 coal stockpile area behind the shop.
EXCESS SPOIL and DEVELOPMENT WASTE - Rule 4.09 Placement; Drainage Control; Surface Stabilization:
- Colowyo was actively dumping spoil from the South Taylor Pit box-cut in the C-C' underdrain area of the East
Taylor Fill. Colowyo was dumping material in the area where the rock crusher was located. It does not appear as
though Colowyo has added any additional material to the top lift of the fill at this point.
- Colowyo was not actively working the A-A' or B-B' underdrain areas of the West Taylor Fill at the time of the
inspection. On 8 November 2010 the Division proposed a decision to approve Technical Revision 88, which
changes the limits of the West Taylor Fill. The public notice for this revision was published on 11 November
2010 so the decision will become final on 22 November 2010 if no comments are received.
- The West Pit fill was observed from the West Pit Pond below. The fill appeared to be well vegetated and stable
at the time of the inspection. No erosional problems were noted. Colowyo has submitted a partial Phase I and II
Bond Release (SL-04) and a partial Phase III Bond Release for most of the reclaimed slopes of the West Pit Fill.
The bond release applications are still under consideration.
- The Streeter Fill was observed from the Streeter Pond below. The fill appeared to be well vegetated and stable at
the time of the inspection. No erosional problems were noted on the face of the fill. Colowyo has submitted a
partial Phase III Bond Release for the entire Streeter Fill. The bond release application is still under consideration.
HYDROLOGIC BALANCE - Rule 4.05 Drainage Control 4.05.1, 4.05.2, 4.05.3; Siltation Structures 4.05.5,
4.05.6; Discharge Structures 4.05.7, 4.05.10; Diversions 4.05.4; Effluent Limits 4.05.2; Ground Water
Monitoring 4.05.13; Surface Water Monitoring 4.05.13; Drainage - Acid and Toxic Materials 4.05.8;
Impoundments 4.05.6, 4.05.9; Stream Buffer Zones 4.05.18:
- Colowyo has completed the work required on the Final East Pit Ditch, North Tributary, East Pit Ditch and Taylor
Tributary Ditch, as required by Notice of Violation CV-2010-004. Colowyo has broken-up all of the large riprap
in the lower portion of the Final East Pit Ditch and they have recut the ditch so it has more depth, width and side
slopes. Colowyo has also lined with the entire constructed length of the Final East Pit Ditch with riprap. Colowyo
has also rerouted the North Tributary, East Pit Ditch in a configuration agreed upon between the Division and
Colowyo. This new ditch location removes the 90° bend in the ditch and changes the location where it intercepts
the Final East Pit Ditch. Colowyo has also recut the North Tributary, East Pit Ditch so that it has more depth,
width and side slopes. Colowyo has also lined the entire constructed portion of the North Tributary, East Pit Ditch
with riprap. Finally, Colowyo has broken-up all of the large riprap in the lower portion of the Taylor Tributary
Ditch and they have recut the ditch so it has more depth, width and side slopes. Colowyo has also lined with the
entire constructed length of the Taylor Tributary Ditch with riprap. Colowyo has provided the Division with as-
built certifications for these three portions of the ditches, dated 5 November 2010. The certifications state that
these portions of the ditches have been constructed according to the designs. The certifications were signed by
Colowyo's professional engineer (contractor) Tom Peterson (Colorado PE License Number 32257). The Division
terminated Notice of Violation CV-2010-004 on 9 November 2010.
- The Streeter Pond (NPDES 001 A) contained water to the weep hole of the discharge pipe and was discharging at
the time of the inspection. The discharge appeared to be clear. The pond embankment was well vegetated and
appeared to be stable at the time of the inspection. No erosional problems were noted on the embankment. This
pond was cleaned last year and there does not appear to be much sediment at the inlet of the pond at this time.
Number of Partial Inspection this Fiscal Year: 5
Number of Complete Inspections this Fiscal Year: 2
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