The coronavirus pandemic pushed a choice between two competing defense-uranium enrichment technologies to January from December, the National Nuclear Security Administration (NNSA) said Wednesday.

It’s the second time this year the agency has delayed the day of reckoning between the AC100 technology Centrus Energy Corp., Bethesda, Md., started developing around 2012 and a smaller-scale enrichment technology that the Oak Ridge National Laboratory has been working on since 2016.

This time, however, the projected delay is only one month instead of one year, and the reason behind the slip is paperwork rather than technological maturity, a NNSA spokesperson wrote in an email.

“Due to COVID-related delays in completing the [Domestic Uranium Enrichment] Analysis of Alternatives, NNSA now expects to complete the AoA (Analysis of Alternatives) in January 2021,” a spokesperson for the semi autonomous Department of Energy nuclear-weapons agency wrote in an email.

Whichever technology the NNSA picks will eventually power the first purely domestic uranium enrichment facility since the Paducah Gaseous Diffusion Plant in Kentucky closed in 2013. In February, the NNSA said it was delaying the AoA by about a year, to the end of December, because the Oak Ridge technology was not mature enough to compete with Centrus’ entry.

The NNSA needs a new domestic source of enriched uranium by the 2040s, when its current supply will run out. The agency initially will require low-enriched uranium to help produce tritium in the Tennessee Valley authority’s Watts Bar Unit 1 and Unit 2 reactors. 

In the meantime, the agency contracted with BWX Technologies [BWXT] subsidiary Nuclear Fuel Services to downblend high-enriched uranium “not usable for other program reasons” into low-enriched uranium that can be used for tritium production until either the Centrus or Oak Ridge technology is ready.

Centrus, the former U.S. Enrichment Corp., is refining its AC100 technology and working the kinks out of an all-domestic supply chain under a three-year, 80/20 cost-share DoE contract — worth about $115 million, including a two-year base and a one-year option — under which the company will build a 16-machine cascade of AC100-M centrifuges at the Portsmouth Site near Piketon, Ohio. 

The initial machines produced under Centrus’ contract will still carry peaceful-use restrictions because they include some components that were not produced in the U.S., Centrus has said.

Under DoE’s interpretation of international laws and rules, defense uranium must come from U.S.-origin minerals and parts, which means the agency cannot rely on American subsidiaries of foreign owned businesses to enrich uranium, or purchase its entire enrichment stock from commodities markets.