Y-12 Working to Address Conduct-of-Operations Issues
NS&D Monitor
6/5/2015
An unusual number of conduct-of-operations problems in a relatively short time has reportedly caused consternation at the Y-12 nuclear weapons plant and accelerated effort to address the common causes. According to an April 17 report by staff of the Defense Nuclear Facilities Safety Board assigned to the Oak Ridge plant, high-level contractor officials convened a meeting to talk about multiple incidents at Y-12 and look for ways to stem the negative momentum. The safety board memo said Consolidated Nuclear Security’s senior director for nuclear operations support at Y-12 and the plant’s production support manager called the meeting. The staff report said one common cause of the different incident appeared to have been poor communications between the production personnel and the people who’re doing maintenance and infrastructure projects at Y-12. The DNFSB staffers said there also appeared to be an “over-reliance” on informal practices in carrying out project associated with production equipment and operating restrictions in some areas of the plant that specializes in work with highly enriched uranium.
A number of issues falling under the category of conduct of operations have been showing up in the defense board reports in recent months, notably in the some of the plants key production facilities – the 9212 uranium-processing complex, the Beta-2E facility where warhead parts of assembled and disassembled; Building 9215, which houses some of the uranium machining operations, and Beta-2, known to be a facility with some lithium activities. The National Nuclear Security Administration did not respond to requests for additional information on the incidents or comment on the conduct of operations by its contractor, Consolidated Nuclear Security.
Beta-2 Incident
CNS did provide some responses to a Beta-2 incident that was revealed in an April 24 report by the DNFSB staff. The staff memo outlined some problems that occurred in early April when Y-12 workers attempted to clean up some lithium from equipment that had been shut down and out of operation since an 2013 incident in which an employee received chemical burns while doing maintenance. Attempts to purge the dust form the equipment and flow it into a glove bag didn’t work because high-oxygen alarms sounded, which forced a halt to that activities and put the facility in a secured alert status for several days.
At one point following that effort, the plant’s Fire Protection Engineering and Development staffers identified additional risk because of continued high oxygen levels, which reportedly meant there was potential for hydrogen generation, state electricity discharge and possible fire and explosive hazards, “CNS management implemented the site’s emergency maintenance procedure and, over the next several days, personnel were able to safely remove the glovebag and eliminate the hazard,” the report stated. CNS said emergency maintenance is defined as “work that requires immediate action to prevent a potential condition.” The contractor said it was a fire hazard in this case.
Contractor spokeswoman Ellen Boatner said the equipment remains out of operation, two years after the original incident. “The equipment was originally taken out of service due to restrictions in the vent lines that was creating an overpressure situation,” Boatner said. “The initial attempt to repair the system did not adequately clear the vent restrictions, and resulted in the release of lithium hydride dust and a personnel exposure to the dust during the post work test. Revisions currently are being evaluated for the removal of the remaining powder in the system before intrusive maintenance can begin to clear the vent restrictions and replace valve seals.”
Other Issues
A number of other issues have drawn attention. On March 10, a “calibration crew” attempted to calibrate the temperature probe on an operating production oven at Beta-2E. This action reportedly triggered an oven system that’s designed to keep the oven from overheating. The result was that the oven was “de-energized.” The safety board report said there were “a number of opportunities” to keep the error from happening at the Beta-2E oven. The work crew reportedly wasn’t fully informed about the operating status of the oven — a communication issue that was cited in multiple incidents.
Y-12 officials refused to talk about the ovens. However, a 2013 safety board report indicated that the ovens are used to “condition” warhead parts before assembly. Other reports have indicated the reports are used during the certification process for some warhead parts.
In another Y-12 incident in late March, production staff identified a noncompliance with nuclear criticality safety requirements in an area of 9212, the hub for enriched uranium processing. As employees prepared to repair a tear in the stainless-steel floor of an area where uranium solutions are processed, the nuclear safety officer noted there was a requirement to empty the solution tanks above the tear in the floor before work began. Apparently because of some confusion and the coming-and-going of some employees, a supervisor gave the go-ahead for the start-up of some worker before the tanks had been emptied. The safety board’s report indicated that a lack of formality in the work plans may have been a contributing issue to the noncompliance.
Another incident in April led to a situation in which a uranium bomb appeared to gain weight during a machining operation. Members of Y-12’s Nuclear Material Control and Accountability team traced the source of the discrepancy to a “documentation error” by a worker in the plant’s 9212 uranium-processing complex. The worker there had reportedly logged the weapon part’s enrichment level as the part’s weight. The DNFSB report said operations personnel at Y-12 missed “several opportunities” to identify the mistake.
