Environmental activists say Utahns living near freeways and railroads may have been endangered by recent shipments of incorrectly labeled radioactive waste headed to Nevada.

They are calling on Gov. Gary Herbert to protest such action by the U.S. Department of Energy, and to say whether Utah and its first responders were warned about the shipments.

“Communities along the interstate highways and railroads in Utah were likely at risk from all of these shipments,” says a letter to the governor from nine activist groups including Healthy Environment Alliance of Utah, the Utah Sierra Club, Utah Physicians for a Healthy Environment, Uranium Watch and Great Salt Lake Audubon.

“Clearly, it is critical that first responders in Utah be aware in advance of these shipments. Were the appropriate Utah authorities notified in advance of any or all of these shipments? That is not clear. We want — and the public deserves — an answer to this important question,” they wrote.

Herbert’s office said the governor has not yet reviewed the letter and its requests.

The letter comes after Nevada Gov. Steve Sisolak earlier this month said the DOE told him it sent 32 shipments of radioactive material incorrectly labeled as low-level waste into Nevada from Tennessee between 2013 and 2018.

He said he was initially told it included “reactive” material, which can release large amounts of thermodynamic energy, but the DOE later said that has not been confirmed. Sisolak and Nevada’s two senators sent a letter calling such shipments “unconscionable.”

Activists wrote that “most of the nation’s radioactive waste must travel through Utah” to the Nevada National Security Site at Yucca Mountain and contend that “Utah bears the greatest risk of an accident or event occurring en route of any state in the country.”

Their letter notes that a bill in Congress, HR2699, seeks to restart the process to store the nation’s spent nuclear fuel rods at Yucca Mountain despite concerns about their suitability. It said it could lead to more shipments through Utah as the sate “is poised to experience a future expansion of rail and truck traffic” because of the state’s planned inland port.

Activists also complained that DOE earlier this year revealed it had quietly shipped a half metric ton of weapons-grade plutonium from South Carolina to Nevada last year despite the latter state’s protest. Nevada attempted to sue to block the waste, but the shipment had already been sent. Sisolak said he was “beyond outraged” by the deception.

Meanwhile, New Mexico Gov. Michelle Lujan Grisham has opposed temporary storage of spent nuclear fuel in her state, arguing it could become an “indefinite storage facility.” Utah fought a similar proposal on Goshute tribal lands for a decade before Private Fuel Storage eventually abandoned the project.

Activists asked Herbert to join efforts by the governors of Nevada and New Mexico by “objecting to the use of Utah roads and rails to ship mischaracterized radioactive wastes,” and to oppose interim storage of spent nuclear fuel in Utah, New Mexico or “any state that objects to such a facility.”

Scott Williams, executive director of HEAL Utah, added, “Utah has a complicated history with nuclear weapons testing, which exposed our citizens to dangerous radioactivity without their knowledge. The last thing Utahns need is another risk to our safety due to a lack of transparency from the federal government.”

Ashley Soltysiak, director of the Utah Sierra Club, said, “It is unconscionable that first responders and the public were not alerted or prepared to handle these imminent threats to their safety. We demand greater transparency from the Department of Energy and Gov. Herbert.”