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Mine Drainage Technology Initiative (MDTI)

Acid Mine Drainage

The Mine Drainage Technology Initiative (MDTI) -  formerly known as the Acid Drainage Technology Initiative (ADTI) - is a forum to address issues associated with mine drainage. This collaborative initiative exchanges information and resources for the purposes of: 

  • Developing an understanding of acidic and toxic mine drainage (MD) so as to better predict, avoid, monitor, and remediate mine drainage
  • Developing innovative solutions to acidic and toxic MD water-quality problems
  • Identifying, evaluating, and developing “best science” practices to predict acidic and toxic MD prior to mining
  • Identifying successful remediation practices for existing sources of acidic and toxic MD and describe the best technology for its prevention

History of the Mine Drainage Technology Initiative (MDTI)

To combat the long-term water pollution impacts of mining in the coal fields of Appalachia and other areas of coal and metal mining, ADTI was formed as a partnership of technical experts from industry, state and federal agencies, and academia who joined together to combat AMD and related water-quality problems from mining and seek solutions. There are two major units: a Coal Mining Sector (CMS) and a Metal Mining Sector (MMS). Working groups in each sector focused on Prediction and Avoidance /Remediation.

Acid Mine Drainage (AMD)

Acid mine drainage (AMD) is a detrimental by-product of coal mining. At present, acid mine drainage continues to pose a potential problem in some areas, despite improved prediction and prevention techniques. It is a long-term water pollution impact of mining in the coal fields of Appalachia and other areas of coal and metal mining. 

AMD or acid rock drainage (ARD), collectively called acid drainage (AD), is acidic water (pH less than 5.0), laden with iron, sulfate and other metals, that forms when geologic strata containing sulfide minerals such as pyrite are exposed to the atmosphere or oxidizing environments.

AMD can form from coal mining, both in surface and in underground mines, but AD can also result from metal mining, or under natural conditions where sulfides in geologic materials are encountered in highway construction, and other deep excavations. Iron sulfides common in coal regions are predominately pyrite and marcasite (FeS2), but other metals may be combined with sulfide in the form of chalcopyrite (CuFeS2), covellite (CuS), and arsenopyrite (FeAsS). Pyrite commonly occurs with other metal sulfides, potential causing AD.

For More Information

Contact Kristin Brown via email (kbrown2@osmre.gov).