TN Americas - a subsidiary of Orano USA - has been selected by Pacific Gas and Electric Company (PG&E) to offload and transfer all used nuclear fuel and Greater-Than-Class C (GTCC) radioactive waste into interim onsite dry storage at Diablo Canyon nuclear power plant in California. The plant is scheduled to shut down in August 2025.

Illustration of the Orano EOS NUHOMS dry storage system at Diablo Canyon with close-up inset showing the Orano transfer equipment and cask containing a sealed canister of used nuclear fuel (Image: Orano)

TN Americas was awarded the contract following a competitive bid process. Under the contract, the company will be responsible for: engineering and licensing to implement Orano's Extended Optimized Storage (EOS) NUHOMS system at Diablo Canyon; design of a new GTCC dry storage facility; fabrication of storage canisters at Orano's manufacturing facility in North Carolina; construction and installation of concrete storage modules; and conducting the pool-to-pad transfer operations for both the used fuel and GTCC waste.

PG&E announced plans in August 2016 to retire Diablo Canyon's two pressurised water reactors - the only remaining nuclear generating capacity in California - at the end of its current operating licences, which expire in 2024 for unit 1 and 2025 for unit 2.

The offload of used nuclear fuel from both units is scheduled to be completed in approximately two years after the reactor shutdowns.

Orano said that by implementing its EOS NUHOMS dry storage system, no major modifications are needed to the existing storage pad or transfer path at Diablo Canyon, and the technology will meet the site's geologic and environmental conditions.

"By transferring the used fuel pool inventory from wet to dry storage, Diablo Canyon can begin reducing significant costs associated with managing used fuel in wet storage," Orano said. "Orano's technology enables a project schedule that fulfills PG&E's and California residents' desire to have a safe, economical, and timely transfer of used fuel into dry storage."

"We are looking forward to performing another safe and efficient pool offload at Diablo Canyon," said Orano USA CEO Amir Vexler. "Our expert teams have successfully performed this work at several other shutdown reactors, exceeding customers' expectations and without regulatory issues."

A panel set up as a forum to provide community input into matters related to the decommissioning of the Diablo Canyon plant has recommended that decommissioning of the plant should begin immediately upon its shutdown in 2025 and be completed within ten years.

Researched and written by World Nuclear News