May 4, 2023
Toxic Coal Ash in Utah: Addressing Coal Plants’ Hazardous Legacy
For decades, utilities disposed of coal ash — the hazardous substance left after burning coal for energy — by dumping it in unlined ponds and landfills. Utah has 14 coal ash dumpsites.
Coal ash contains hazardous pollutants including arsenic, boron, cobalt, chromium, lead, lithium, mercury, molybdenum, radium, selenium, and other heavy metals, which have been linked to cancer, heart and thyroid disease, reproductive failure, and neurological harm.
Industry’s own data indicate that across the country 91% of coal plants are currently polluting groundwater above federal health standards with toxic pollutants.
Coal ash remains one of our nation’s largest toxic industrial waste streams. U.S. coal plants continue to produce approximately 70 million tons every year.
Despite EPA’s 2015 Coal Ash Rule, which created the first-ever safeguards for coal ash disposal, many coal ash dumps remain unregulated due to sweeping exemptions for legacy coal ash ponds and inactive landfills.
The exempted coal ash dumps are sited disproportionately in low-income communities and communities of color. The EPA is expected to issue a proposed rule to address these exemptions in May 2023.

Action Needed
The magnitude of harm from recklessly dumped toxic coal ash requires decisive action from federal and state regulators.
- Utilities must be required to comply with the law and immediately clean up their pollution.
- EPA and states must make enforcement a priority and act quickly to ensure that utilities leave communities with sites that benefit rather than harm their health, environment, and economic status.
- EPA must swiftly strengthen the Coal Ash Rule to address the many legacy ponds and inactive landfills that are unregulated, and to prohibit coal ash used as fill unless protective measures are put in place, to ensure all Utah communities are protected from coal ash pollution.
Eight Regulated Coal Ash Disposal Sites in Utah
Utah utilities operate eight federally regulated coal ash ponds and landfills containing more than 52 million cubic yards of toxic waste at five power plant.
Coal ash has caused groundwater contamination at all of Utah’s regulated dumpsites.
Some of these dumps are contaminating water at dozens of times the safe levels of certain pollutants.
One of them, Hunter Power Plant, is the ninth most contaminated coal ash site in the U.S.
Despite the serious and widespread water contamination, no Utah company, to date, has initiated a plant-wide cleanup to restore groundwater, despite the legal requirement to do so.
Bonanza | Vernal | Deseret | 2 landfills | Arsenic (x13), Beryllium (x1), Fluoride (x15), Molybdenum (x34), Selenium (x5) |
Hunter | Castle Dale | PacifiCorp | 1 landfill | Boron (x16), Cobalt (x28), Lithium (x210), Molybdenum (x11), Radium 226+228 (x2), Selenium (x7), Sulfate (x62) |
Huntington | Huntington | PacifiCorp | 1 landfill | Boron (x28), Chromium (x1), Cobalt (x2), Lithium (x94), Molybdenum (x1), Selenium (x3), Sulfate (x10) |
Intermountain | Delta | Intermountain Power Service | 2 unlined ponds, 1 landfill | Arsenic (x32), Boron (x6), Lithium (x33), Mercury (x7), Molybdenum (x4), Sulfate (x9) |
Sunnyside | Sunnyside | Sunnyside Cogeneration Assoc. | 1 landfill | Arsenic (x1), Lithium (x26), Selenium (x3), Sulfate (x13) |
All data on groundwater contamination from coal ash derived from the utilities’ publicly accessible CCR Compliance Data and Information websites, and exceedances were calculated by Environmental Integrity Project.
For more information on regulated coal ash sites in Utah, see Mapping the Coal Ash Contamination.
Six Unregulated Coal Ash Legacy Ponds and Inactive Landfills in Utah (ash dumps exempted from the 2015 Coal Ash Rule)
In addition, Utah hosts at least six unregulated inactive coal ash landfills and legacy ponds that escape federal regulation (Table 2). The exact number remains unknown because utilities are not required to report these sites.
These dumps are almost certainly contaminating water and threatening health and the environment; however, monitoring data are not currently available for most unregulated sites.
As we anticipate EPA’s proposed rule on legacy ponds and unregulated landfills in May 2023, a concern remains that the agency will not address coal ash that was dumped off site or used as fill.
Carbon | Helper | PacifiCorp | 2 | 2 | Unknown |
Huntington | Huntington | PacifiCorp | 0 | 2 | Yes – Industry data |
These data were developed by using EPA datasets relied upon in their 2007 and 2014 CCR risk assessments (Human and Ecological Risk Assessment of Coal Combustion Residuals) and comparing those datasets to the universe of regulated units.
“Industry data”: All data on groundwater contamination from coal ash derived from the utilities’ publicly accessible CCR Compliance Data and Information websites, and exceedances were calculated by Environmental Integrity Project.
“EPA damage case” denotes a site where US EPA has found documented groundwater contamination from coal ash.
For More Information
Christine Santillana, Legislative Counsel, Earthjustice, csantillana@earthjustice.org
Lisa Evans, Senior Counsel, Earthjustice, levans@earthjustice.org.
More on Coal Ash in Utah
Coal Ash in States, Territories, Regions
Earthjustice fights in the courts for a long-term solution to the toxic menace of coal ash. And we act on behalf of dozens of clients and over 100 coalition partners to defeat legislative attempts to subvert federally enforceable safeguards of coal ash.
Earthjustice’s Clean Energy Program uses the power of the law and the strength of partnership to accelerate the transition to 100% clean energy.