Wyoming and Coal Ash Disposal in Ponds and Landfills Summary

The document details the disposal of 2.1 million tons of annual coal ash in Wyoming, highlighting that 17 ponds across five plants exist, with three rated as "significant hazard." It notes that 11 ponds are over 30 years old and identifies specific historical releases and groundwater contamination issues at sites like the Naughton, Dave Johnston, and Jim Bridger power stations.

• Wyoming generates 2.1 million tons of coal ash annually, which is managed across 17 ponds located at five different plants.
• The infrastructure for coal ash storage in Wyoming shows significant age and risk, with 11 ponds exceeding 30 years of age and three ponds officially rated as a "significant hazard."
• Storage capacity for 15 of the 17 Wyoming ponds totals 20,497 acre feet, or more than 6.6 billion gallons, with a single pond at the Jim Bridger Power Station accounting for 11,534 acre feet.
• Historical releases at Wyoming sites include a 55,000 cubic yard fly ash spill at Naughton Power Station, a 14,400 gallon process water overflow at Dave Johnston Power Station in January 2009, and monthly seepage of approximately 10,000 gallons at Jim Bridger Power Station.
• A 2007 EPA risk assessment found that four surface impoundments and landfills in Wyoming are unlined, two are only clay-lined, and four lack a leachate collection system.
• At the Dave Johnston Power Plant, groundwater monitoring showed exceedances of the primary Maximum Contaminant Level (MCL) for cadmium and secondary MCLs for manganese and sulfate.

APA

Earthjustice (n.d.). Wyoming and Coal Ash Disposal in Ponds and Landfills Summary. https://earthjustice.org/wp-content/uploads/wy-coal-ash-factsheet.pdf

Chicago

Earthjustice. Wyoming and Coal Ash Disposal in Ponds and Landfills Summary. n.d. https://earthjustice.org/wp-content/uploads/wy-coal-ash-factsheet.pdf.

Wikipedia

{{cite report |author=Earthjustice |title=Wyoming and Coal Ash Disposal in Ponds and Landfills Summary |url=https://earthjustice.org/wp-content/uploads/wy-coal-ash-factsheet.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{earthjusticendwyoming, author = {{Earthjustice}}, title = {{Wyoming and Coal Ash Disposal in Ponds and Landfills Summary}}, institution = {Earthjustice}, url = {https://earthjustice.org/wp-content/uploads/wy-coal-ash-factsheet.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }