The Savannah River Site’s Defense Waste Processing Facility (DWPF) resumed operations Tuesday following a nearly two-month outage for routine maintenance.
Meanwhile, the site’s Modular Caustic Side Solvent Extraction Unit (MCU), which treats a different form of liquid waste, will remain offline until mid-October. Both facilities were shut down on Aug. 8 for maintenance, which meant liquid waste processing was on hold across the South Carolina facility until the DWPF reopened on Oct. 2.
Site spokeswoman Sonya Goines said an MCU cleaning device called a coalescer is being replaced. The MCU serves as an interim waste processing facility for the Savannah River Site’s salt waste, which makes up about 90 percent of the 35 million gallons of Cold War-era, radioactive liquid waste stored in 41 underground tanks. The other 10 percent is sludge waste. The MCU converts the salt waste into a less harmful material that can be permanently stored at the site’s Saltstone facilities. It will eventually be replaced by the Salt Waste Processing Facility, which will have a significantly increased processing capacity.
During the coalescer replacement, SRS liquid waste contractor Savannah River Remediation (SRR) flushed out and cleaned the entire MCU. The system is expected to go back online in mid-October.
The Defense Waste Processing Facility converts sludge waste into a glassy, less harmful form for storage. The outage provided time for preventive maintenance on the DWPF’s electrical distribution system, which delivers power to the facility at the correct voltage and frequency. The work included cleaning the electrical components of the system, testing the insulation for possible degradation, and make sure the system is operating properly.
The recent DWPF outage was not linked to the suspension of liquid waste processing from February 2017 to June of this year. That outage was forced by the failure of Melter 2, the part of the DWPF that receives and mixes the waste, converting it into its new form. The site spent $3 million swapping out the 65-ton vessel.
