Mine Mapping and Surveying - Coal Waste Impoundments: Risks, Responses, and Alternatives - page 57

performs optimally under all geological and topographic conditions, multiple
geophysical techniques may be necessary to reduce the probability for error to
an acceptable level (see Chapter 5 ).
The primary use of underground mine maps is to determine accurately the
dimensions of pillars and mine openings and to locate the mine with respect to
the surface and any horizontally or vertically adjacent surface or other
underground mines (Shackleford, 2001). 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), coal outcrop, and 100-
foot overburden contour or other prescribed mining limit;
• Mineral lease boundaries, surface property or mine boundary lines, and
identification of coal ownership.
A coal section, which describes the mined thickness of the sequence of
coal, rock, and partings, is listed on the mine map. Coal sections are typically
recorded when a survey spad is set (see definition in glossary). The coal section
permits calculation of mined coal tonnage, percentage of coal recovery, and
percentage of reject (in-seam and out-of-seam rock). An example of a portion of
a typical underground mine map is shown in Figure 4.1 .
Underground and surface mine maps are collected and stored both on the
state level and by MSHA and OSM. Operators of underground mines are
required to submit maps to MSHA at least annually for the approval of
ventilation plans. These maps are maintained at the various MSHA district
offices or archived at a central location until the mine closes. Following mine
closure, a copy of the final map is forwarded to the OSM National Mine Map
Repository in Pittsburgh, Pennsylvania (see below). Therefore, MSHA is a
source of maps for active mines only.
There is considerable activity at the state level concerning mine maps. For
example, the Commonwealth of Virginia has embarked upon an ambitious
program to accumulate mine maps and place them in a digital database
( Sidebar 4.1 ). Related activities underway in West Virginia and Kentucky are
discussed in Sidebars 4.2 and 4.3 . Comparison of the mapping