Coal Waste Impoundments Risks, Responses, and Alternatives (2002) / Chapter Skim
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4 Mine Mapping and Surveying
4 Mine Mapping and Surveying
Pages 71-86
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From page 71... ...
The adequacy of existing mine maps and recommendations for the storage and preservation of maps make up the first part of the chapter. While mine maps provide information critical to the characterization of a site, there are significant limitations to some maps, particularly those for abandoned mines and mines operating before 1969.
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From page 72... ...
be determined using aerial topographic measurements. UNDERGROUND MINE MAPPING The use of inaccurate or incomplete mine surveys and maps may result in construction of an impoundment in an area not known to have been mined; if unknown mine workings are present, the impoundment could suffer unexpected structural failure (Franklin et al.', 1997~.
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From page 73... ...
The following information relevant to site characterization is included on a typical underground mine map (30 C.F.R. §§ 75.1200, 1200-1~: · All pillared, worked out, and abandoned areas, pillar locations, sealed areas, future projections, adjacent mine workings within 1,000 feet, surface or auger mines, mined areas of the coalbed, and the extent of pooled water; Dates of mining, coal seam sections, and survey data and markers; Surface features (e.g., railroad tracks, public roads)
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From page 74... ...
74 :-~ ~~ O: 8-31-00 ~ °1 o ._ C' a) Ct o 1 · Cal Q _ in > An or o ugly m~ Go cr:vo:CO 3~.
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From page 75... ...
Geological Survey topographic quad rangle sheets and +150 feet for those tied to geologic quadrangle sheets; · +10 feet for mines located by survey; and · +250 feet (at best) for abandoned mineland portal locations.
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From page 76... ...
OSM has no regulation requiring the submission of maps but does have informal arrangements with MSHA to provide copies of the final map for abandoned mines. In addition, some copies of mine maps are prepared to illustrate mine ventilation systems, and these maps may not contain all the mine map information required by 30 C.F.R.
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From page 77... ...
As mine maps from active operations are submitted to MSHA and state agencies, copies should be forwarded to OSM, so the archival data can be updated. MSHA, in coordination with OSM and the state agencies, should undertake a thorough and comprehensive effort to acquire maps of abandoned mines, concurrently with the updating of maps of active mines.
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From page 78... ...
The committee concludes that the establishment of uniform mine surveying and mapping standards is essential to ensure that underground coal mines are accurately located" with respect to other mines and surface structures, including refuse impoundments. Therefore, the committee recommends that MSHA set standards for minimum closure error for all underground closed-loop surveys and that a closed-loop survey be maintained within a standard distance (to be determined by MSHA)
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From page 79... ...
The data can also be used for vertical location of the active mine in the framework of overlying and underlying seams, which may be actively mined or may contain abandoned mines, and for identification of undulations in the mine floor that frequently correlate with poor roof or floor conditions. The thickness of the outcrop barrier is critical to the evaluation of blowout, blow-in, or breakthrough potential (see Chapters 3 and 6~.
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From page 80... ...
80 TABLE 4.1 Required State Surveying Closure Standards COAL WASTEIMP6UNDMEN~ State Mine Surveys Property Surveys AL IL IN KY None/federal MD OH *
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From page 81... ...
Geological Survey topographic maps list both North American Datum 27 latitude and longitude and state plane coordinates, so mines can be located easily on commonly available maps. The committee concludes that the variety of mapping and coordinate systems in use at present increases the potential for misinterpretation or inaccuracy in underground mire locations.
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From page 82... ...
Thus, conversion of a particular mine map from local to state plane coordinates, requires knowledge of the geographic limits of a particular coordinate transformation. The committee recommends that appropriate coordinate transformation equations be listed on the mine map.
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From page 83... ...
The committee recommends that MSHA establish standards to improve and maintain the location of surface controls. Monuments should be referenced to state plane coordinates and at least one monument located in Norm American Datum 27 or 83, or latitude and longitude (Sidebar 4.5~.
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From page 84... ...
Therefore, the committee recommends that coal seam names not be the sole basis for determining the vertical location of an abandoned mine. SUMMARY Accurate mine maps are critical to establishing the location of underground mine workings with respect to existing or proposed coal refuse impoundments.
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From page 85... ...
, · Recording the depth of the last cut taken to a level of accuracy to be determined by MSHA, · Using state plane coordinates or latitude and longitude, and bottom-of-seam elevations as the map base reference, Listing of appropriate coordinate transformation equations on the mine map, Adding a qualifying statement to accompany any coordinate transformation that is based upon the alignment of surface features, Improving and maintaining the location of surface controls, Determining which mine permit documents should be retained, in what form, and for how long, · Avoiding the use of coal seam names as the sole basis for determining the vertical location of an abandoned mine.
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From page 86... ...
Following mine closure, a copy of the final map is forwarded to the OSM National Mine Map Repository in Pittsburgh, Pennsylvania (see below)
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