Mountaintop Removal/Valley Fill Coal Mining Impacts on Birds

Background

Photo: Vivian Stockman, Southwings.org

Mountaintop removal mining is a type of surface mining found in the Appalachian portions of Kentucky, West Virginia, Virginia, and Tennessee. As its name suggests, mountaintop removal mining involves removing the top of a mountain in order to uncover the coal seams contained near the mountain's surface. Explosives are used to break the mountain's rock, and massive earth-moving equipment (such as "draglines") removes the spoil - the dirt and rock that formerly composed the mountaintop. Federal law normally calls for excess spoil to be placed back in the mined areas, returning the lands to their approximate original contours. However, in mountaintop removal mining, vast quantities of spoil are carried to surrounding valleys and dumped, hence the term mountaintop removal/valley fill. Why not simply replace the fill at the mine site and return the mountain to its former state? The answer is because broken rock occupies more volume than the original mountain, and so there is always spoil left over. Also there are concerns with spoil stability in steep terrain.

Mountaintop removal mining has been practiced in some form since the 1960s, but it became a prevalent coal mining technique in parts of central Appalachia during the 1990s for several reasons. Firstly, as the demand for electricity increased, so has the demand for the relatively clean-burning, low-sulfur coal found in Appalachia. Secondly, coal supplies nearest the surface have been significantly depleted. Thirdly, draglines and other large surface mining equipment are now capable of moving over 100 cubic yards of earth in a single scoop.

Impacts on Birds

One consequence of mountaintop removal mining is that streams flowing through the valleys are buried. Large mines may be surrounded by several valley fills because of the sheer volume of broken rock and spoil created. Depending on the local topography and the profile of those valleys, a single fill may be over 1,000 feet wide and over a mile long. Until recent years, excess spoil from coal mining was generally placed in the extreme headwaters of streams, affecting primarily ephemeral streams that flow intermittently only in direct response to precipitation in the immediate watershed. Because smaller upstream disposal sites are exhausted and because of the increase in mountaintop mining activity, today the volumes of a single stream fill can be as much as 250 million cubic yards. As a result, streams are eliminated, stream chemistry is harmed by pollutants in the mining overburden, and downstream aquatic life is impaired. From 1985 to 2001, an estimated 724 stream miles in West Virginia, Kentucky, and parts of Virginia and Tennessee were covered by valley fills, and 1,200 miles of headwater streams were directly impacted by mountaintop mining activities.

Forested ridgetops, midslopes, and riparian areas are all affected by mountaintop removal mining/valley fill operations. Most of these areas are in mature forested habitat, but are cleared of all timber prior to mining. Species that rely on mature forest habitats that are abundant in the Appalachian region-Kentucky Warblers in the understory, Worm-eating Warblers in cove hardwoods, Wood Thrush is mesic hardwoods, and Louisiana Waterthrush along wooded streams-are all impacted by forest fragmentation and habitat loss caused by mountaintop removal mining. Most notably though is the Cerulean Warbler, a species that has declined rapidly over the last 40+ years, which relies on mature forests, and whose core range mirrors the Appalachian Coalfields. Ceruleans need large tracts of mature, structurally diverse deciduous forests on the upper portions of ridges. Mountaintop mining removes these mature forests, punching a large opening in a forested block, which has been shown to reduce breeding densities and nesting success of Ceruleans (and other species reliant on mature forests) near these openings. Additionally, the contour of the area is permanently changed, reducing shaded stream habitat and diverse cove hardwoods unique to the region. Finally, and possibly most importantly, mined areas are often not reclaimed to forests. It is much less expensive and time-consuming to reclaim an area to grasses than it is to plant tree seedlings, but succession to a forest on a mined area is extremely slow. Most times, mined 'spoils' or 'overburden' (the rock and dirt from the top of the mountain) are compacted so tightly that trees are unable to establish a root system, meaning that mined areas reclaimed in this manner will remain grasslands (or maybe shrublands) for many decades or centuries to come. Cumulatively across what should be a forested region, mountaintop mining removal and valley fill operations impact bird habitats and their populations.

Solutions

There is little that can be done to mitigate for the loss of riparian habitat and stream quality due to the process of valley fill. As long as millions of tons of mining waste are dumped into valleys, birds and other wildlife will be negatively impacted. There are, however, some mitigation measures that can be undertaken to lessen the effects of forest habitat loss on the mountaintop itself. Recent research by the U.S. Geological Survey and West Virginia University show that breeding Cerulean Warblers avoid forest edges where they meet reclaimed mine grasslands (up to 650 feet into the forest), and so occur at much lower densities there compared with intact forests. Therefore, far more forest is lost to breeding Ceruleans than is actually cleared for mining. However, if reclaimed mines were reforested, rather than simply planted with non-native grasses, this "edge effect" would be quickly reduced, even though the newly planted forests would not support breeding Ceruleans for quite some time.

However, mines reclaimed to grasslands and shrublands have created early successional habitat sorely needed throughout the region. In some places, reclaimed mine sites offer the only early successional habitats in the area, and now support populations of Henslow's Sparrow, Golden-winged Warbler, American Woodcock, and Northern Bobwhite, all species of high conservation priority.

To increase Cerulean Warblers and manage for Henslow's Sparrows we must be strategic and innovative in habitat conservation planning and restoration. Several partnerships have arisen to address these conservation needs. The Appalachian Mountains Joint Venture (AMJV) is one such partnership; the Appalachian Regional Reforestation Initiative (ARRI) is another. ARRI is generating interest through on-the-ground efforts and research; in 2006, ARRI's state partners reported 15,000 acres reclaimed, with over nine million trees planted throughout the region. For these efforts, ARRI was recently awarded the Department of the Interior's prestigious Cooperative Conservation Award.

ABC, through its support of the AMJV, is also exploring future habitat restoration efforts with ARRI. Together, AMJV and ARRI can design an Appalachian landscape to support and increase priority birds in the region and implement large-scale reforestation through their many partners.