The first canisters of vitrified radioactive waste have been poured at a new melter at the US Department of Energy's Savannah River Site (SRS) in South Carolina. The melter, at the Defense Waste Processing Facility (DWPF), installed by liquid waste contractor Savannah River Remediation (SRR), treats high-level radioactive waste, currently stored in tanks at the site. The 75-ton teapot-shaped vessel blends the waste with a borosilicate glass known as "frit" to form a molten glass mixture, SRR said. The vitrified mixture is then poured into stainless steel canisters for safe storage onsite until a permanent disposal facility is available.

It is the DWPF’s third melter in 20 years, replacing Melter 2, which reached the end of its design life in 2017 after 14 years of operation during which it poured 4900 tonnes) of glass into 2819 canisters. SRR president and project manager Tom Ford said the company had optimised the system outage to replace the melter and perform other critical facility upgrades, integrating the schedule with a separately planned outage to tie in the Salt Waste Processing Facility (SWPF) into current liquid waste facilities. The SWPF, which is undergoing commissioning and testing, will process low-level salt waste which accounts for more than 90% of the SRS tank wastes.

SRS was built in the 1950s to produce materials for nuclear weapons, primarily tritium and plutonium-239. Five reactors were built on the site along with two chemical separations plants, a water extraction plant, nuclear fuel and target fabrication facility and waste management facilities. Savannah River faces a massive legacy waste clean-up task.  “Stabilising and safely storing highly radioactive waste is an important part of the Department of Energy’s mission to remediate the Cold War-era liquid waste at SRS,” said DOE Manager Jack Craig. “The new melter allows us to continue this important mission.”

SRR, the liquid waste contractor at SRS is a team of companies led by AECOM with partners Bechtel National, CH2M, and BWX Technologies, Inc. Subcontractors for the contract are AREVA, Atkins, and AECOM N&E Technical Solutions.


Photo: Melter 3 poured its first canister of vitrified high-level radioactive waste (Credit SRS)