Fluor Federal Services, prime contractor for deactivation of the former Paducah Gaseous Diffusion Plant in Kentucky, got a wag of the finger from the Energy Department over a breach of criticality safeguards last year involving a pipe containing potentially damp fissile materials, according to a document DOE posted online late Wednesday.
The incident, reported to DOE on Nov. 18, 2015, centered around the possibility of wet uranium in the disused gaseous diffusion facility. Water is a moderator, or a substance that may facilitate criticality, an uncontrolled nuclear chain reaction.
The Office of Enterprise Assessments (EA) enforcement letter, dated Oct. 14, cited Fluor for a “loss of documented nuclear criticality safety (NCS) controls for some large-diameter piping” due to “loss of moderation control” at the Kentucky cleanup site, Steven Simonson, director of the Enterprise Assessments office of enforcement, wrote to Bobby Smith, Paducah program manager for Fluor Federal Services.
Ultimately, Simonson wrote, there was only a “low likelihood that these sections of piping could contain enough fissile material to pose a criticality concern.”
Reached by phone Thursday, Cory Hicks, a spokesman for Fluor Federal Services, deferred to DOE Environmental Management headquarters in Washington, which did not respond to the request for comment by press time for Weapons Complex Monitor.
According to the enforcement letter, Fluor Federal Services in July 2015 discovered moisture levels in excess of criticality safety standards in a different stretch of pipe separate from the one that provoked the November 2015 incident. In the earlier case, sample results were verified the following month, according to Simonson: “A level 3 NCS violation was identified at this time because the moisture levels had exceeded the limit for over 6 months. This represented the loss of one essential element of the double contingency principle.”
The Oct. 14 letter imposes no requirements upon Fluor Federal Services and requires no response from the contractor. The office “elected to issue this Enforcement Letter to convey concerns with the safety incident,” but DOE had chosen “to not pursue further enforcement activity against [Fluor Federal Services] at this time,” Simonson wrote.
Simonson wrote “the Office of Enforcement will continue to monitor [Fluor Federal Services’] efforts to improve nuclear safety performance.”
The Paducah Gaseous Diffusion Plant enriched uranium for Cold War weapons programs, and later for commercial power plants. The plant ceased refining uranium for commercial customers in 2013 and is now being deactivated by Fluor Federal Services under a three year contract awarded in 2014 and worth about $420 million.
