AIKEN, S.C. – Liquid waste operations at the Savannah River Site (SRS) have successfully restarted after a comprehensive, 15-month outage to replace and upgrade equipment and facilities.
The Defense Waste Processing Facility (DWPF) is again pouring canisters of glassified high-level waste after workers completed extensive maintenance during the outage since February 2017. That’s when SRR began replacing the DWPF melter, the key vessel that vitrifies high-level radioactive waste into a stable glass form contained within stainless steel canisters.
Chemical operations (i.e., pretreatment of sludge to prepare for vitrification) at the DWPF resumed May 8. On May 31, DWPF restarted glass pouring when a minor issue was discovered with the seal between the melter and the canister.
The first canister was poured using the new melter in December 2017. After pouring seven canisters, the facility entered another outage to complete facility maintenance.
In parallel, salt waste processing at SRS has restarted after workers completed upgrades and modifications to the interim salt waste processing facilities, known as the Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit. Some outage work included replacing three of the unit’s contactors and decontaminated salt solution pre-filters, vent modifications, and other maintenance activities.
Restarting liquid waste operations has been a priority for EM.
“Stabilizing and safely storing the radioactive waste at SRS is an important part of DOE’s Environmental Management mission,” DOE-Savannah River Manager Mike Budney said.
Installation of a new melter and the maintenance work during the outage better positions SRS to advance the liquid waste mission safely and successfully, Budney said.
Because melter replacements and facility upgrade outages are built into the overall liquid waste system plan, there are no production impacts due to the outage.
The outage also enabled maintenance work at the SRS Tank Farms, including rebuilding waste transfer valves and valve boxes to support improved reliability. Waste transfer line and transfer pump work continued on Tank 49 in H Tank Farm to prepare for future Salt Waste Processing Facility (SWPF) support. Savannah River Remediation (SRR), the liquid-waste contractor at SRS, took advantage of the overall system outage to chemically clean the 2H Evaporator to ensure ability to manage overall tank space.
Underlying all the SRS liquid waste operations are the documented safety analyses, which provide the technical basis for ensuring safe, compliant operations of the liquid waste facilities. SRR engineers revised the analyses during the outage, and they have now been implemented in their respective facilities.
SRR employees were equipped for the complex outage, and they always kept an eye toward safety, SRR President and Project Manager Tom Foster said.
“What I am most proud of at the outcome of this outage is the exceptional safety performance displayed by our people,” Foster said. “It’s been a technically challenging time, and our employees have delivered excellent operational results, but most importantly completed the work in a safe and disciplined manner.”