2015-06-09_PERMIT FILE - C1996083A ‎(6)‎

• Permit No: C1996083A
• IBM Index Class Name: Permit File
• Doc Date: 6/9/2015
• Doc Name: TOC and Introduction
• Section_Exhibit Name: Volume IX Coal Mine Waste Disposal Area No. 2
• Media Type: D
• Archive: Yes

evaluates the maximum height of the Gob pile at 150' instead of the original pile height of
118 feet.
Buckhorn Geotech evaluated the as -built configuration of gob pile #4. It was prepared
September 5, 2012. The analysis is based on actual construction of the pile, and utilizes
soil parameters as discussed in the original report dated February 1, 2007. The as -built
configuration has been determined to be stable.
Buckhorn Geotech prepared a stability analysis evaluating the Gob Pile #2 expansion. It
was prepared November 9, 2012. The report concludes the pile will be stable with
slopes no steeper than 3h:1 v with 15' wide terraces on 50 to 60' intervals with the first 50'
sloped no steeper than 2.5h:1 v.
Buckhorn Geotech prepared a stability analysis evaluating gob pile #4 based on DRMS
request to evaluate slopes in the as -built configuration with a steepness up to 2h:1v. The
pile was found to be stable in the as -built configuration. The report was prepared on
November 20, 2012.
Buckhorn Geotech prepared a revised stability analysis for the gob pile expansion area.
It was prepared July 29, 2013. The report analyzed two sections, A -A' and F -F' and
concluded that the pile will be stable with slopes no steeper than 2.5h:1v with 15' wide
terraces on 60' intervals. This revision to the steepness of the slopes is for the area
represented by Section A -A' and is not a blanket slope revision for the entire pile
configuration. In addition, where gob pile #2 and #4 meet, Buckhorn recommends
ripping into existing gob to a minimum of 12" and moisture conditioning by blending new,
wet gob with existing gob. Buckhorn recommends keying into existing gob, in alternating
layers.
Huddleston Berry Engineering & Testing (HBET) prepared a stability analysis dated
March 18, 2014 to analyze a temporary drying area on top of gob pile #2. Gob will be
end dumped in piles that will be a maximum of 20' high with 1.5H: 1V side slopes. A25'
buffer zone between the face of the gob pile and the end dumped gob will be maintained
at all times.
Huddleston Berry Engineering & Testing (HBET) prepared a stability analysis dated
October 1, 2014 to demonstrate the weight of the coverFll pile west of the haul road on
gob pile #2 does not compromise the overall stability of the gob pile.
Huddleston Berry Engineering & Testing (HBET) prepared a stability analysis dated
September 19, 2014 to demonstrate the weight of the coverfill pile east of the haul road
on gob pile #2 does not compromise the overall stability of the gob pile.
TR -98 _19- 01/15