With appeal resolved, EPA re-issues air permit for Navajo coal treatment project

The U.S. Environmental Protection Agency will announce in the Sept. 26 Federal Register that it has issued a final permit decision for a Clean Air Act Minor New Source Review (NSR) Permit in Indian Country to the Salt River Project Agricultural Improvement and Power District (SRP) for the construction of a refined coal treatment system (RCTS) at the Navajo Generating Station (NGS).

The permit authorizes SRP to construct and operate the RCTS, including ancillary equipment, to treat coal with cement kiln dust and calcium bromide so as to reduce emissions of oxides of NOx and mercury.The EPA issued a final minor NSR permit decision for the NGS RCTS Project on Aug. 31, 2016. The permit became effective on that date. Judicial review of this final permit decision, to the extent it is available, may be sought by filing a petition for review in the U.S. Court of Appeals for the Ninth Circuit within 60 days of this Sept. 26 notice. 

The permit for the RCTS was initially issued by the EPA on April 20, 2016. The EPA’s Environmental Appeals Board (EAB) received one petition for review of the permit, from a private citizen, and on Aug. 30 the EAB denied the petition for review. Following the EAB’s action, the EPA issued a final permit decision on Aug. 31. All conditions of the NGS RCTS permit, as initially issued by the EPA on April 20, are final and effective as of Aug. 31.

The Navajo Generating Station (NGS) has a combined power generating capacity of 2,250 net MW and consists of three existing coal-fired steam generating units (Boiler Units 1, 2, and 3), associated air pollution control devices, and auxiliary equipment. The facility was constructed in 1970 and is located on the Navajo Nation Indian Reservation approximately five miles east of Page, Arizona. Units 1, 2, and 3 are operated by the Salt River Project Agricultural and Power District (SRP) and co-owned by the following six entities: U.S. Bureau of Reclamation, SRP, Los Angeles Department of Water and Power, Arizona Public Service, Nevada Power and Tucson Electric Power. The plant receives coal with a maximum sulfur content of 1.5% by weight from Peabody Western Coal Co.’s Kayenta Mine.

NGS is adding a new Refined Coal Treatment System (RCTS) which adds calcium bromide and cement kiln dust to the coal prior to being pulverized for combustion in Units 1, 2, and 3. The project includes:

  • Installation of two coal feed belt conveyors;
  • Installation of two mixing pugmills where cement kiln dust and calcium bromide will be applied to the coal;
  • Installation of two refined coal product belt conveyors;
  • Installation of two dust collection and filtering systems for the new coal handling operations;
  • Installation of three 150-ton cement kiln dust storage silos, each equipped with baghouses;
  • Installation of two 20-ton day bins for cement kiln dust, each equipped with baghouses; and
  • Installation of a 8,700-gallon storage tank and two 405-gallon day tanks for calcium bromide storage.
About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.