ALBUQUERQUE, N.M. (AP) — Los Alamos National Laboratory won't be able to meet a deadline for getting toxic waste from decades of building nuclear bombs off its northern New Mexico campus before wildfire season peaks, the U.S. Department of Energy said Friday.

In a statement, the department said it has notified the New Mexico Environment Department that it can't move the last of thousands of barrels of waste containing things like contaminated gloves and tools until officials are sure it is safe.

A canister shipped from Los Alamos to the Waste Isolation Pilot Project has been linked to a radiation release Feb. 14 at the underground repository in southeastern New Mexico. Officials are investigating whether hundreds of other barrels from Los Alamos that are currently stored at the West Isolation Pilot Plant, Los Alamos and in West Texas are at risk of releasing radiation.

The waste was packed with cat litter to absorb moisture. Officials are trying to determine whether a switch from inorganic to organic litter is to blame for a chemical reaction with nitrate salts that caused the accident that contaminated 22 workers and indefinitely shuttered the plant.

Deputy Undersecretary David Klaus said the energy department has "made great strides in cleanup at the Los Alamos National Laboratory," but it is halting shipments "until we can reassure the public that it is safe to do so."

"This was a tough decision to make and the Department remains committed to solving this issue and resuming shipments," Klaus said.

The New Mexico Environment Department said it "was disappointed but not surprised," noting the top priority is public safety.


Los Alamos spokesman Matt Nerzig said the lab remains "determined to meet our obligations to the state of New Mexico" and is working to help find the cause of the radiation release.

The agreement for removal of the waste by June 30 was reached after a massive wildfire lapped at the edge of lab property three years ago, raising concerns about the thousands of barrels of waste that were being stored outside. There are still 57 barrels on the campus, which officials have repacked into special containers and are now storing under a dome with 24-hour monitoring and fire protection systems.

Also Friday, the Waste Isolation Pilot Plant is expected to detail its plans for sealing off areas where the suspect canisters are stored.

New Mexico Environment Secretary Ryan Flynn ordered the Department of Energy and the contractor that runs the Waste Isolation Pilot Plant to submit their plans for permanently sealing the two underground rooms where more than 300 barrels of the potentially dangerous containers of waste are stored.