2017-04-06_REVISION - C1981041 (7)

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JAMES A. BECKWITH SNOWCAP COAL / TR -69 / SUMMARY OF FONTANARI OBJECTIONS / PG. 4 4. Two Subsidence Troughs: On April 6, 2016, Fontanari consultants inspected the two Tracts and found two subsidence troughs: one in the NE corner of the Carey Tract the other in the NE corner of #71 Tract east of the air ventilation shaft. The locations of these features wre professional surveys; elevations were determined; and a plat showing the location of these troughs was submitted to DRMS and Snowcap. Photographs were also provided. At no time since has Snowcap ever acknowledged the existence or location of these subsidence troughs. Its sub -contract, Fugro Consultants, made reference to their existence. However, the plugs are not proposed to be placed in either of these subsidence troughs. Moreover, Snowcap does not propose, as part of its Repair, that either trough be filled with top soil to make the surface cultivatable. 5. There Is More Than One Sinkhole: Snowcap's Report and Repair Plan only references one sinkhole: the one in the lateral ditch. In fact, however, there are as many a 12+ sinkholes surrounding the subsidence troughs in both the Carey and #71 Tracts. If we believe Mr. Boulay's Proposed Decision in SL -08, all of these sinkholes have developed since June, 2014. Several of these sinkholes are quite large: in fact, larger than the sinkhole involved in the June, 2014, incident. There is no record that Snowcap, Mr. Stover, Mr. Boulay or any other DRMS representative re -visited the Carey and #71 Tracts to determine whether the surface conditions were static or in active subsidence. None of these persons or entities reported the existence, or emergence, of the approximately 13 sinkholes surrounding the two subsidence troughs. The conclusion here is obvious. Plugging one sinkhole will not stop, deter or prevent flood irrigation waters from entering the underground caverns through any of the other sinkholes presently on the properties or which might emerge at any future time on these properties. Installing the bentonite or a low slump concrete plug is rather like putting a cork in the bathtub drain while there are 5 other holes in the bathtub. The effort is futile; a waste of time; and a waste of money. 6. One Tract With Troughs / One Tract Without Troughs: The Carey and #71 Tracts are quite comparable. They are adjacent to each other. Each has historically been cultivated in various crops and trees. Each has been subject to the snow, rain and other climatic conditions. Each has been subjected to flood irrigation: one in 1989 and the other in 2014. However, the bulk of the Carey Tract (east of present Carey Pond) lacks any subsidence -induced sinkholes and does not have surface subsidence troughs. The eastern edge of the Carey Tract and the entirety of 471 Tract has sinkholes and surface subsidence troughs. Why this difference? The answer lies in the 1978 GEX Mine Workings Map on file with DRMS. This map shows that only a portion of the Carey Tract was actually mined, while the entirety of the #71 Tract was mined. The sub -strata is quite simple. There is a basaltic aggregate extending to depths of approximately 50 feet; then a sandstone strata for another approximate 50 ft.; and, then an estimated 8 ft. coal seam. The coal seam was removed via room -and -pillar mining methods, allowing for eventual collapse of the coal cavern. Where the coal was not mined, the coal seam continues to support the sandstone and basaltic aggregate constituting the overburden.