NRC seeks public comment on SMR regulation

19 December 2019

The US Nuclear Regulatory Commission (NRC) is seeking public comment on proposals to apply risk-based emergency preparedness requirements to small modular reactors (SMRs) and other new technologies. The proposed rule would include a scalable approach for determining the size of the emergency planning zone around such facilities.

(Image: NRC)

The NRC's emergency preparedness programme for nuclear power plants has up to now focused on large, light-water reactors. The proposed rule, together with a draft regulatory guide, considers advances in facility design and safety research and their application to future operation of SMRs and other future technologies including non-light water reactors and certain non-power production facilities, the regulator said.

"The alternative requirements and implementing guidance would adopt a risk-informed, performance-based, and technology-inclusive approach. The alternative requirements would include a scalable approach for determining the size of the emergency planning zone around each facility, based on the distance at which possible radiation doses could require protective actions," the NRC said.

The new rule would only apply to SMRs and so-called ONT (other nuclear technology) applications, not currently operating reactors or fuel cycle facilities. For existing plants, the plume exposure pathway emergency planning zone (EPZ) covers a radius of about 10 miles (16 km), with an ingestion pathway EPZ covering an area about 50 miles in radius. Future SMR and ONT applications are likely to reflect a "wide range of potential designs" that have smaller source terms and also incorporate emergency planning considerations as part of the design, with enhanced safety margins "and/or the use of simplified, inherent, passive, or other innovative means to accomplish their safety and security functions," the rule notes.

Following the publication of the proposed rule in the Federal Register, the public and other interested parties will have 75 days to comment on emergency preparedness issues including the performance-based approach and the scalable EPZ approach, the NRC said.

The NRC approved the proposed rule on the same day it authorised the issuance of an early site permit to Tennessee Valley Authority for the potential construction of SMRs at its Clinch River site near Oak Ridge, Tennessee.

Researched and written by World Nuclear News