_GENERAL DOCUMENTS - C1981017 ‎(142)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Permit Index Doc Type: General Correspondence
• Media Type: D
• Archive: No

Fred Banta - 4 - September 11 , 1985
As in the case of waste flows on the coal processing waste pile, the waste
flows at the rock tunnel refuse pile were, in the opinion of the operator's
consultant, with which I also concur, the result of the operator' s activities
which did not comply with the approved specifications for placement of
material at the rock tunnel refuse pile. Once again, the operator failed to
comply with the approved plan. The specifications for placement of waste were
developed by the applicant design consultant, Lincoln DeVore, Inc. , in
October, 1979. This design report was submitted by the operator as a portion
of a permit revision request for approval of the Mid-Continent Tunnel project
and its associated tunnel refuse waste pile. Within that report, the
applicant's consultants present the following material placement and
compaction specifications on page 10;
"Fill for the outer portion of the slopes should be placed
in lifts not to exceed 12 inches loose thickness, and
compacted to at least 90 percent of its maximum proctor
density, ASTM D-698. Fill material should be brought to
the proctor optimum moisture content,-+ 2 percent, prior
to compaction, and should be compacted by mechanical
means. No water flooding techniques, such as jetting,
ponding, or puddling, should be used in the placement of
fill . No particles in excess 10 inches diameter should be
placed in the fill . These placement requirements will
apply to the outer portion of the fill , where the potential
failure surface is located. We recommend the compaction
procedures described above for the material from the toe of
the slope to a distance of 15 feet beyond the top of the
slope. Material located beyond this zone may be spread in
lifts not exceeding 2 feet thickness and tracked into place
with a heavy dozer or similar equipment. Under no
circumstances should fill material be simp y� e_nd=dumped'
without being spread or worked."
Once again, the purpose of the standard specifications is to provide guidance
to the operator to achieve pile stability. Failure to comply with the
specifications may subject the pile to potential instability, which manifested
itself at the rock tunnel waste pile in the spring of 1984. In failing to
follow their own standard specifications for construction of the rock tunnel
waste pile, the applicant demonstrated a lack of diligence and imprudence.
In the case of both the coal processing waste pile and rock tunnel refuse pile
at the Coal Basin Mines, Mid-Continent Resources failed to comply with its own
standard specifications and design standards contained in their approved
permit application. In doing so, the operator subjected both piles to
potential failure, which manifested itself in the spring of 1984. Both of
these situations were predictable and avoidable. Both the piles had been the
subject of previous required design studies and analyses. In both cases, the
design reports contained standard specifications intended to prevent exactly
the sort of situation which occurred in the spring of 1984. Further, in the