By Timothy Gardner

WASHINGTON (Reuters] -A U.S. Nuclear Power Regulator has directed staff to provide documents which could be used to review a 2020 application for a new nuclear reactor. The request was made after an engineer raised questions about the reactor’s ability to withstand severe earthquakes.

Dan Dorman was the nuclear Regulatory Commission’s executive director of operations. He reviewed a John Ma complaint about the NRC’s approval of NuScale, a design for a nuclear power station.

NuScale is majority-owned by a construction and engineering firm Fluor Corp (NYSE 🙂 received approval to design a 50-megwatt small module reactor (SMR). It is now planning to construct the Carbon Free Power Project at the Idaho National Laboratory. The first reactor will be online in 2029, and the full operation of the plant in 2030.

SMRs like NuScale are seen by some as an opportunity to reduce emissions and possibly decrease Europe’s dependence on Russian oil. NuScale wants to also build plants in Poland, Kazakhstan.

Ma, in an internal memo he sent to NRC officers shortly after the approval for 2020, claimed the building’s design to contain reactor units and the spent fuel pool was not designed to ensure it would withstand large earthquakes without collapse. It may also be more vulnerable to small earthquakes.

Ma stated that a collapse of the reactor building could lead to a large and early release of radioactive material into the atmosphere, which could cause death.

In February, Dorman wrote to Ma that he concluded the NRC’s basis for accepting NuScale’s measure of strength for the reactor’s building design “was not sufficiently documented,” documents posted on the NRC website https://www.nrc.gov/docs/ML2205/ML22056A017.pdf on Wednesday showed.

Dorman required the Office of Nuclear Reactor Regulation of the agency to report on its evaluation of NuScale’s “stress-averaging approach”. If necessary, Dorman also ordered that the application be updated and evaluated for any “impacts” to 2020 design approval.

There was uncertainty about whether additional actions might affect the timeline, which has already been delayed several times.

Beyond what was stated in documents, the NRC press office did not comment. Dorman didn’t immediately reply to our request for comment.

Diane Hughes, Vice President, Marketing and Communications at NuScale said that the NRC should consider professional opinions such as Ma’s to ensure a strong culture of nuclear safety.

She stated that the NuScale structure’s robustness is what makes it the most secure design approved by NRC.

According to a science advocacy group, Ma’s concerns were alarming.

“NuScale’s business case is based on its assertion that it is a safer nuclear reactor, now it’s time to prove it by addressing these safety concerns,” said Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists.