The Department of Energy on Monday said it has started moving a metric ton of plutonium out of South Carolina after three federal appeals judges on Friday shot down the agency’s argument that a lower court’s order to remove the material from the palmetto state by Jan. 1, 2020 was legally flawed.

Barring an escalation to the U.S. Supreme Court, or a rehearing in the Fourth Circuit Court of Appeals, the agency now has a little less than a year to move the bomb grade material out of South Carolina. DoE has 90 days from the Oct. 26 order to take the case to the Supreme Court, or 45 days from Oct. 26 to ask for a rehearing before all 18 Fourth Circuit judges.

“The Department will confer with the Department of Justice about the decision,” a spokesperson for the National Nuclear Security Administration wrote in an email Monday. “In the meantime, we are already engaged in moving the 1 [metric ton] of plutonium out of the state and expect to move approximately half this [calendar] year and half next year.”

South Carolina sued DoE in U.S. District Court in 2016, claiming the agency had failed to meet its mandate under federal law to either convert a ton of bomb-grade plutonium into commercial reactor fuel by Jan. 1 of that year or remove it from the state by that date. The District Court judge sided with the state and, on Dec. 20, 2017, ordered DoE to remove a ton of plutonium from South Carolina by the start of 2020.

The Energy Department appealed, saying District Judge J. Michelle Childs failed to consider legally available options that would have given the agency more time to remove the plutonium from the Savannah River Site in Aiken, S.C.

The appeals court judges rejected that argument, saying the roughly two-year deadline Childs set was essentially the same amount of time Congress believed it would take DoE to move the plutonium out of state when legislators wrote the federal law that codified the convert-or-ship-out provision central to South Carolina’s lawsuit.

DoE had planned to convert surplus weapon-grade plutonium into reactor fuel using the now-canceled Mixed Oxide Fuel Fabrication Facility (MFFF) at Savannah River.