PUBLIC NOTICE- Black Thunder, School Creek, and North Antelope Rochelle Mines Exceptional Events (PM10) Documentation Packet

Wyoming Department of Environmental Quality  | view as a webpage

Wyoming Department of Environmental Quality

PUBLIC NOTICE- Black Thunder, School Creek, and North Antelope Rochelle Mines Exceptional Events (PM10) Documentation Packet

Thunder Basin Coal Company (Black Thunder Mine), Peabody Powder River Mining (North Antelope Rochelle Mine), and Peabody School Creek Mining, LLC (School Creek Mine) have requested that exceedances of the 24-hour Particulate Matter 10 (PM10) standard collected at the RO-1 Site TEOM sampler, 36 Site TEOM sampler, and SC-2 Site TEOM sampler on December 19, 2016 be flagged as due to an exceptional event under 40 CFR 50.14, “Treatment of air quality monitoring data influenced by exceptional events.”  These facilities have submitted a documentation packet to the Air Quality Division (AQD) in support of its request to flag the exceedances cited above.  The AQD is soliciting comments from the interested public on this documentation packet.  The documentation packet submitted to the AQD is available for public comment and the public will be allowed a period of thirty (30) days to submit written comments. 

Notice is hereby given that the State of Wyoming, Department of Environmental Quality, Division of Air Quality, proposes to flag these data as influenced by an exceptional event.

Comments may be submitted by mail to the Division's Ambient and Emission Monitoring Supervisor contact, Cara Keslar, Division of Air Quality, Department of Environmental Quality, 200 West 17th Street, Third Floor, Cheyenne, Wyoming 82002 or by fax to (307) 635-1784.  Comments may also be submitted electronically through the following website: (  Comments submitted by email will not be accepted.  Interested parties may examine the documentation packet and all relevant supporting materials on AQD’s website ( as well as the Division's Cheyenne office.  Arrangements can be made with the Division to copy relevant materials if necessary (a fee will be assessed for reproductions).  In accordance with the Americans with Disabilities Act, special assistance or alternate formats will be made available upon request for individuals with disabilities.

Public comments must be received no later than June 12, 2018.  All comments received by the close of business on June 12, 2018 will be submitted to EPA’s Region 8 along with the documentation packet to be considered in arriving at a final determination of treatment of data influenced by exceptional events and will be retained on file in the Cheyenne office.