Modifications Completed Faster than Expected
Kenneth Fletcher
WC Monitor
8/22/2014
After a months-long unexpected pause in operations at the Savannah River Site’s H-Canyon facility to make numerous upgrades, the facility is poised to start several new missions. That includes production of plutonium oxide and downblending of used fuel at the site’s L Basin, as well as a mission expected to begin next year to process liquid highly enriched uranium from Canada. “The H-Canyon facility is an incredibly flexible asset for the Department of Energy. We are just really getting back to a place where we are exploiting that,” Paul Hunt of M&O contractor Savannah River Nuclear Solutions told WC Monitor this week. “It’s been a long time since we’ve been processing plutonium and uranium in the canyon. It’s been many years since we’ve had both dissolvers up and running on different missions. You get a sense of energy about the facility now that we are up and running in two different missions and preparing for a third.”
Late last year SRNS self-identified issues that needed to be corrected before new missions could begin, which in part has delayed the start of the plutonium oxide effort that had been set to begin last year. “We were preparing for some just routine inspections of some of the canyon exhaust systems,” Hunt said. “There were some things that we needed to do to upgrade the system based on what we saw in preparing for the inspections. They were potential release paths in a seismic event that we felt needed to be dealt with. So we took a pause on canyon operations and put this on a critical path for resuming those.”
H-Canyon Restart ‘Top Priority’
Restarting operations at H-Canyon was “the top priority for the site,” Hunt said, leading to a concentrated push that allowed the 16 modifications to be completed in five months rather than the anticipated eight months. The scope of work was defined in January, design changes were developed in January and February by the engineering department and the construction department began field work in March, going six days a week, 10 hours a day until the end of the project in July. “We crunched the design work. We threw a lot of resources to get an accelerated design process and likewise in the field mods,” Hunt said. “The reality is that if this played out with the normal resources available in the facility this could have played out with the design and modifications over 12 months, easily.”
The work involved modifications at many points in the ventilation systems that could be potential release pathways. “We installed new fire doors, which required pulling out and then welding in new frames, which is a major undertaking in a radiological environment,” Hunt said. “There were a number of pipes that had to be cut off and capped again in potentially contaminated areas. There was the potential for backflow through some of the HEPA filters, so we had to go into some of the HEPA filters and install upgrades to ensure they were good to withstand the backflow.”
Conduct of Operations Improvements Noted
But the modifications were not the only factor in delays, as conduct of operations issues led the Department last to suspend its readiness assessment of the plutonium oxide mission. However, conduct of operations has now been validated by the SRNS readiness assessment and DOE’s assessment has since resumed. “We have demonstrated the necessary safe operations to start the facility up and will continue to drive that kind of discipline. We learned a lot in that,” Hunt said.
Plutonium Oxide Mission to Startup Underway
H-Canyon and HB-Line are slated to eventually produce 3.7 metric tons of plutonium oxide from surplus plutonium by 2019. That material had originally been intended as feedstock for the Mixed Oxide Fuel Fabrication Facility, but it will still be needed even though the fate of that project is now uncertain. “It still needs to get to an oxide either way, so this advances the disposition capability for this excess plutonium,” Hunt said. “We are on schedule to produce several cans of the oxide this fiscal year and to have that analyzed so that we can validate the process.”
Startup was initialized this month, but Hunt notes the original delays in the mission. “That’s why when we landed on these mods, we wanted to get through them as quickly as we could because we were ready to start that system up,” he said. “We are behind considerably from when we intended to start that up. … First we need to get it started up and get some baseline data, but we’ve got several plans to look at how we optimize production both with capabilities at the National Lab and LEAN tools for the process mapping.”
Used Fuel Mission Almost Ready to Start
Another mission to process 36 bundles of potentially vulnerable sodium reactor experimental fuel was put on hold last year when the need for modifications was discovered. It was resumed in mid-July and the effort was recently completed. Right now SRNS is flushing contaminants out of the system before beginning a larger, sustained campaign to downblend used nuclear fuel at the site’s L Basin to low enriched uranium for commercial reactor. “That new used fuel campaign will kick off probably in mid-September,” Hunt said. “We are in the flushes right now. The intent is, we wanted to get into this campaign this fiscal year.”
