Locations

• The U.S. Geological Survey (USGS) is mapping the locations of naturally occurring asbestos throughout the country. The survey has so far mapped areas in the eastern, southwestern, central and Rocky Mountain areas of the United States, with strong bands of natural asbestos deposits found along the eastern edge of the Appalachian Mountains from northern New Jersey to Alabama. The USGS also performed an independent study of natural asbestos in El Dorado, California, at the request of the U.S. Environmental Protection Agency (EPA).
  
  

EPA Asbestos Regulations

• The EPA enforces asbestos regulations under the Clean Air Act (CAA) and Toxic Substance Control Act (TSCA). These regulations were established with respect to asbestos-containing material and their uses. Under authority from these regulations, the EPA has banned products, required remediation of asbestos from buildings and regulated the disposal of contaminated materials. So far, these regulations have not been applied to naturally occurring asbestos. However, the EPA is involved in testing sites where natural asbestos has been found and has issued guidelines for activity in such areas.
  
  

EPA Guidelines

• Because natural weathering and human activity can release asbestos mineral fibers into the air, human exposure to this type of asbestos by inhalation is a serious health concern. The EPA has issued guidelines for reducing human exposure. These guideline are provided to state and local governments, as well as, private industries such as construction and mining. The EPA suggests engineering controls to suppress dust in areas where naturally occurring asbestos has been found through the use of covers and caps, vegetation, fencing and landscaping.
  
  

EPA Testing and Superfund Cleanup

• The EPA has taken action under Superfund law (also called the Comprehensive Environmental Response, Compensation and Liability Act, or CERCLA) to assess asbestos exposure at public areas in El Dorado Hills, California. A petition for cleanup was made to the EPA in 2003 after the discovery of naturally occurring asbestos in the soil at a local high school. The EPA cleaned up the site in 2004 primarily through soil removal and landscaping. The EPA continues to work with state and local agencies to investigate asbestos in the El Dorado Hills area.
  
  

Delegation of EPA Authority to States

• The EPA can delegate its authority to state and local agencies and this seems to be the current approach to controlling human exposure to naturally occurring asbestos. For example, in California, the Air Resources Board has enacted Airborne Toxic Control Measures, which apply to construction activities such as grading and quarrying. In Fairfax County, Virginia, where naturally occurring asbestos has been mapped by the USGS, construction activities must be approved by the county health department to ensure a plan of compliance is in place to prevent migration of contaminated dust from the construction site.