By John Stang
The majority of the Nuclear Regulatory Commission believes its updated nuclear power plant safety rules contain measure determined necessary to protect the public.
Agency Chairman Kristine Svinicki offered the message in a May 3 letter to Sens. Tom Carper (D-Del.) and Sheldon Whitehouse (D-R.I.). She was responding to concerns the lawmakers raised in an April 1 letter regarding the agency’s final post-Fukushima safety rule for U.S. power plants.
The approved rule was the result of years of work at the NRC following the March 2011 earthquake and tsunami caused three reactors to melt down at the Fukushima Daiichi power plant in Japan.
The main thrusts of the new regulations require licensees to ensure that facilities’ reactor cores and spent fuel pools remain cooled, and reactor containments are not undermined, even if a plant’s alternating-current power sources are crippled. Licensees must also ensure spent fuel pool water levels can be measured after an incident.
However, the final rule does not require licensees to incorporate newer data on flooding and earthquake hazards in mitigation plans for beyond-design-basis events — an item NRC staff added in an earlier draft.
“The final rule did not contain these requirements because the commissioners determined that ongoing staff efforts to reevaluate external hazards at every facility and take site-specific action, if warranted by the reevaluation, sufficiently addressed this issue,” according to Svinicki in her letter to Carper and Whitehouse.
The NRC would add regulatory requirements if ongoing staff inspections determine such a need exists, Svinicki wrote.
Svinicki, along with Commissioners Annie Caputo and David Wright, voted in January to keep out the extra requirements in approving the final rule. Commissioners Jeff Baran and Stephen Burns, the latter of whom retired earlier this month, dissented.
Baran outlined his dissenting position in a separate May 2 letter to Carper and Whitehouse. He specifically emphasized climate change as a threat to increase the risk of flooding.
“The rule allows licensees to ignore these reevaluated hazards with their FLEX (pumps, hoses and other reactor equipment) strategies and only be prepared for the old, outdated hazards,” Baran wrote. “In the years leading up to the decision on the draft final rule, the commission had repeatedly and unanimously found that updated safety standards addressing the reevaluated hazards were necessary to adequately protect the public. … Failing to protect the equipment from the real earthquake and flooding hazards makes no sense.”
The nuclear industry, states, and public interest groups did not call for dropping the extra requirements as they submitted comments on the rulemaking, Baran wrote.
The April 1 Carper-Whitehouse letter came one day before a Senate Environment and Public Works Committee oversight hearing on the agency attended by all five commissioners.
“In the final rule, NRC decided to ignore staff recommendations (made in 2015 and tentatively approved in 2016) and make preventive actions to address beyond-design flooding and seismic events voluntary,” the two lawmakers wrote. “Most of industry has already addressed these issues, but not requiring mandatory action to continually address the …main issues that arose during Fukushima seems very concerning.”
At the committee hearing, Whitehouse asked the commissioners whether “there some kind of industry back door” in which nuclear corporations approached the commission after the public-comment period ended for the rule but before January’s vote. The issue was also raised during the hearing.
An enclosure attached to Svinicki’s letter, addressing specific questions posed by the senators, said: “Neither I nor anyone on the Commission received any comments outside the comment period regarding the Mitigation of Beyond-Design-Basis Events (MBDBE) Rule, SECY-16- 0142, asking for the Commission to change mandatory requirements to voluntary requirements in the final rule from the draft final rule.”
The agency also addressed the senators’ concerns about the danger posed to nuclear plants by flooding exacerbated by climate change. “The Commission viewed the existing regulatory processes, as well as the ongoing efforts to reevaluate flooding and seismic hazards, as sufficient to maintain reasonable assurance of adequate protection of public health and safety, including an assurance that any sea level rise will not negatively impact the safe operation of nuclear power plants near coastlines. … These processes account for the Fourth National Climate Assessment and other scientific reports on sea level rise.”
