Longwall Mining Schematic (Source: Energy Information Administration)
Faced with growing pressure to stop the ravages of mountaintop removal in the Appalachian coal fields, coal companies have quietly been expanding the use of longwall mining in southwestern Pennsylvania and now in central Illinois.
Longwall mining is a high extraction technique where coal is removed in 1,400 ft. panels that stretch for miles. Unlike traditional room and pillar mining, in a longwall mine no coal pillars are left in place to provide surface support above the panel. Hydraulic supports are used to hold the roof up at the working face of the coal seam. As the longwall machine advances, the supports are moved forward and the roof behind them collapses, causing the land above to drop by 4-8ft.
Planned Subsidence?
While the coal industry and regulatory agencies use the euphemism “planned subsidence” to describe what happens above a longwall mine, the reality is that longwall subsidence is a serious seismic event – like an earthquake – that causes major damage. The overlying rock layers are subjected to enormous strains, causing rock layers to fracture. This has serious consequences, including:
- Damage to underground aquifers and the loss of water in rural wells.
- Alteration of surface drainage – flowing streams may pond, or lose water as stream beds crack.
- Damage to structures on the surface, including homes, roads, agricultural buildings and dams
Unethical and Unsustainable
Longwall mining is a highly destructive practice that goes against the ethic of land stewardship American agricultural communities are founded upon. Our highly productive farmland deserves to be fully protected – a coal company’s desire for one time profits should not be allowed to compromise the health of our lands and waters.
Coal companies that practice longwall mining are not required to prevent damage – they are only required to compensate citizens whose property they have damaged or destroyed. In the coalfields of southwestern Pennsylvania and West Virginia, coal companies have destroyed miles of streams, houses and farmland. Rural residents often choose to sell their homes and farms rather than stay and face the consequences of the longwall machine, leading to the depopulation of rural areas above the longwall mines.
Now that major coal companies have decided to bring longwall mining to Illinois, citizens are demanding protections for our lands, waters and communities from the threat of longwall mining.
Learn More
These organizations work on longwall mining issues in Appalachia:
Don’t forget – subsided ground fallen futures