New Mexico Geological Society Annual Spring Meeting — Abstracts

At the time the General Mining Law of 1872 was written, there was no recognition of the environmental consequences of direct discharge of mine and mill wastes into the nation’s rivers and streams or the impact of this activity on the availability of drinking water supplies, and riparian and aquatic habitats. Miners operating on federal lands had little to no requirement for environmental protection until the 1960s and 1970s, although the dumping of mine wastes and mill tailings directly into the nation’s rivers was halted by an Executive Order in 1935. It is important to recognize that these early miners were not breaking any laws, because there were no laws to break. In New Mexico, there are tens of thousands of inactive or abandoned mine features in 273 mining districts (including coal, uranium, metals, and industrial minerals districts). Many of them pose only a physical hazard, which is easily but costly to remediate. Although most of these mine features pose little or no environmental or stability threat to the public and environment, many of them have not been inventoried or prioritized for reclamation. During the late 1880s, government agencies began to track mine accidents. Indeed one of the earliest recorded accidents in the west was an explosion at the White Ash coal mine in the Cerrillos district, where 24 men died. Other mine accidents occurred during the late 1800s and early 1900s. Environmental accidents also have occurred at some New Mexico mine sites, mostly before the 1980s. In July 1979, 370,000 cubic meters of radioactive water containing 1,000 tons of contaminated sediment from a failure of the United Nuclear uranium tailings dam traveled 110 km downstream in the Rio Puerco in western New Mexico. Evidence of slope instability at the Goathill North waste rock pile at Questa molybdenum mine was observed as early as 1974, but was not stabilized until 2004. Today, more than three dozen Federal laws environmental laws and regulations cover all aspects of mining in an attempt to prevent such accidents, including the Clean Water Act (CWA), Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA or Superfund act), Federal Mine Safety and Health Act of 1977, among others. Mine accidents that were once common in the late 1800s and early 1900s, are rare today, but still occasionally happen. Legacy issues still remain and should be inventoried. Today, one important aspect of mine planning in a modern regulatory setting is the philosophy, actually, the requirement in most cases, that new mines and mine expansions must have plans and designs for closure. This philosophy is relatively new and attempts to prevent environmental accidents common in the past. Mine development of the distant and even not-too-distant past commonly did not consider mine closure, except perhaps to plan for safeguards and contingencies. Mine closure planning is necessary not only for safety reasons, but also for environmental reasons.