The Defense Nuclear Facilities Safety Board (DNFSB) said in a Feb. 17 report that employees with Savannah River Remediation (SRR), the South Carolina site’s liquid waste contractor, had completed removing lagging and insulation from the bottom of the pot to make repairs. Once removed, workers filled the evaporator with heated flush water, which allowed them to see the leaks. “SRR and the subcontractor are currently developing a path forward for repairing the pot,” the DNFSB said in the report, which was made public this month.
Problems with the 3H Evaporator have been noted over the past year. In early 2016, the DNFSB reported an estimated 3,000 gallons of salt waste had leaked from the pot, and that it would either have to be repaired or replaced.
SRR responded to the problem by halting use of the pot, one of its two evaporators in the H-Area Tank Farm, which houses 29 tanks and millions of gallons of highly radioactive liquid waste. Evaporators are crucial to removing much of that waste from the tanks. They boil the salt waste water, causing the water to separate from the waste, thus reducing the waste volume to about 25 to 30 percent of the original volume. Reducing, and ultimately removing, all of the waste in the tanks is necessary in order to close the tanks and reduce the environmental threat they pose.
The repaired evaporator, or a new pot, is expected to be available for use by the second quarter of fiscal 2019.
