Let’s clear the air about Orano’s dry cask storage system chosen for Diablo Canyon

Were you surprised? We were – to see such a harsh letter sent to our shared customer by a competitor with scathing misinformation and misdirection about Orano and our NUHOMS used nuclear fuel dry storage system.

As covered in The Tribune editorial, “A jilted Diablo Canyon contractor accuses PG&E of ‘reprehensible act.’ Is it sour grapes?,” the recent letter made false claims about our dry storage technology, its seismic capabilities and its status as an NRC-licensed system.

In our industry, meeting the unique needs of our customers means that supplier companies are sometimes partners and sometimes competitors, but rarely contentious.

Let’s clear the air of any confusion or doubts with factual references and resources.

Regarding our system’s licensing status, Orano’s robust EOS NUHOMS (NUclear HOrizontal Modular System) planned for the secure storage of used nuclear fuel at Diablo Canyon Power Plant is a fully licensed system under Nuclear Regulatory Commission Certificate of Compliance CoC-1042.

To meet the unique geologic and environmental requirements of the Diablo Canyon site, NUHOMS was selected as a licensed system with existing enhanced seismic resilience and thermal (heat) dissipation

To further reduce the wait time for transferring the high-heat, used fuel assemblies from the site’s wet storage to dry storage, we are submitting an amendment to our license — as is standard in the U.S. nuclear energy industry — for review and certification by the NRC. This amendment provides thorough analyses detailing our system’s ability to securely receive and store Diablo Canyon’s high-thermal, used fuel under the proposed schedule.

The NRC review affects the schedule — not the already robust licensed capabilities of our system.

Another surprising claim in the letter is that, during an earthquake, Orano’s “freestanding modules are apt to slide and fall in the Pacific Ocean ….”

The writer offers no basis for this statement, and there is none.

Contrary to that claim, rigorous scientific analyses published by the U.S. Department of Energy’s Sandia National Laboratories show the stability of horizontal systems.

Sandia’s 2012 study, “Seismic Considerations for Spent Nuclear Fuel Storage in Dry Casks,” investigated the seismic response of typical vertical and horizontal used fuel cask systems under a wide range of variables. Sandia determined that rectangular cask horizontal systems — the design basis for Orano’s horizontal NUHOMS design — will not tip over during severe seismic events or move more than a few centimeters on the pad.

Our dry storage technology has proven its durability and reliable operation in all situations at more than 30 locations across America.

We fully meet all five criteria important to the Diablo Canyon Community Engagement Panel:

• Safely transfer used fuel to dry storage within four years of plant shutdown
• Dry storage system meets unique DCPP site requirements
• Simple access to inspect dry storage casks
• Minimize dose (side-by-side placement creates self-shielding benefit)
• NRC licensed system and oversight

We applaud the diligent effort and thorough technical evaluation by PG&E during the competitive bid process for the Diablo Canyon pool offload. For Orano, our quality performance is our loudest statement and our customer service is our proudest accomplishment.

Curtis Roberts is the Senior Director of Communications for Orano USA.

This story was originally published April 20, 2022 at 9:32 AM.