NUHOMS Receives First and Only NRC-Approved Aging Management Plan for Canisters Containing High Burn-up Fuel

Image Source: ExelonThe Nuclear Regulatory Commission (NRC) recently approved a 40-year license renewal for the AREVA TN NUHOMS® dry-cask independent spent fuel storage installation at Exelon Generation’s Calvert Cliffs Nuclear Power Plant. The approval includes an aging management program that includes periodic inspections of the used fuel dry storage systems and components to ensure potential aging effects are identified and effectively managed.

This means that AREVA TN’s NUHOMS® system is the only nuclear fuel dry storage system with an NRC-approved Aging Management Program (AMP) addressing Chloride-Induced Stress Corrosion Cracking (CISCC) and canisters with high burn-up fuel (HBU).

The NUHOMS® AMP at Calvert Cliffs includes a Dry Shielded Canister (DSC) External Surfaces AMP, a Horizontal Storage Module (HSM) AMP, a Transfer Cask AMP, a Transfer Cask Lifting Yoke AMP, a Cask Support Platform AMP, and a High Burn-up Fuel AMP.

In support of the NUHOMS® system license renewal and life extension, AREVA TN has also designed an innovative, patent-pending inspection ring system for the NUHOMS® canisters. The inspection ring will operate with the existing horizontal transfer cask, providing the unique ability to safely inspect 100% of the canister’s surface without heavy lifting.

According to Mike McMahon, senior vice president, AREVA TN Americas, “As a pioneer and industry leader in used nuclear fuel dry storage, we are pleased to have a detailed and advanced AMP for the NUHOMS® system approved by the NRC. We are dedicated to continuous improvement of AMPs and inspection tools and processes that are essential for ensuring safe continued storage.”

Calvert Cliffs currently has 76 NUHOMS® systems loaded on site. The licensed AMP covers existing canisters on site and will also cover future NUHOMS® 32PHB DSCs scheduled for the facility. The site’s current AMP will be carried out remotely using high-resolution cameras, fiber optics and other tools. Surface chloride inspections will be conducted using AREVA TN’s proven SaltSmart™ system.

AREVA TN is an industry leader in the development of inspection tooling and technology. AREVA TN participated in the first campaign for in-service inspection of actual loaded canisters at Calvert Cliffs in 2012, and is a key member of the industry team conducting the HBU Dry Storage Research Project.