_INSPECTION - C1982057 ‎(64)‎

• Permit No: C1982057
• IBM Index Class Name: INSPECTION
• Doc Name: Inspection Report
• Inspection Date: 5/20/2010
• Email Name: DTM
• Email Name: SB1
• Media Type: D
• Archive: No

III. COMMENTS - COMPLIANCE
Below are comments on the inspection. The comments include discussion of observations made
during the inspection. Comments also describe any enforcement actions taken during the inspection
and the facts or evidence supporting the enforcement action.
General Comments
This was an aerial inspection of the Seneca II-W Mine. Harry Ranney of the Division took 25 oblique to near
vertical digital aerial images during the fly-over of the mine site on May 20, 2010. The Tie Across Haul Road
portion of the permit area was not covered by the imagery.The images were viewed by Dan Mathews of the
Division on 5-27-10. Snow had recently melted off the reclamation, although there were remnant snow patches
in drift locations along the lee side of the eastern ridgeline. Muddy conditions were prevalent across much of the
mine site, with puddles evident in many locations, apparently from recent snow or rain on soils already moist to
saturated from snowpack melt.
Roads
It was not evident that significant road maintenance work had been completed since the previous inspection.
Conditions may have remained too muddy to allow for maintenance in most areas. Maintenance grading, culvert
maintenance and ditch repair/riprap installation is warranted in various locations(see previous inspection report
dated 5/14/10).
Hydrologic Balance
Snowpack had recently melted off most reclaimed areas, but conditions were muddy throughout the site, with
puddles evident in low lying areas. Sediment Ponds 016 and 016A were full and discharging; other sediment
ponds were not covered by the photos.
Stock Ponds T-18, T-20, T-5, T-26 and T-27 all contained full or nearly full pools.
Backfill and Gradinq
Permanent Channels and Hillslope Erosion
It appears that most areas have remained inaccessible for rill and gully repair work due to muddy conditions.
There is widespread rill erosion on recently reclaimed slopes in the 016/016A watershed. Much of the rilling was
initiated by heavy rain on saturated soils in the spring of 2009. The operator implemented significant erosion
control and repair measures in 2009, including construction of numerous erosion control surge structures and
low gradient cross ditches. The surge structures and ditches appear to have largely functioned as designed, and
the extent of erosion from 2010 runoff is much reduced compared to 2009. However, channel maintenance
will be necessary in a number of locations, particularly immediately downstream of the surge structure
outlets. Also, installation of additional cross ditches in series, or other appropriate measures, appears
to be necessary to allow for stabilization of hillslopes in portions of the PM-2A and PM-26 channel
networks, and possibly other slope locations,where concentrated rill erosion is evident. Appropriate
measures will need to be addressed and implemented by the operator under the Rill and Gully Plan, this field
season.
Slides and Damage
Two areas affected by significant landslides in the past were covered by the photos taken on May 20. One of
these slide areas is the slide complex in the lower 016/016A drainage of the South Extension area, which
exhibited additional movement on the in-slope of Sediment Pond 016A, as described in the April inspection
report. A remediation plan based on geotechnical and hydrologic evaluation of the slide complex is being
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