By William Opalka

The Nuclear Regulatory Commission last week ordered its staff to redo an accident analysis for the Indian Point nuclear power plant in New York, ruling the original study used incorrect parameters and underestimated the economic impacts of a severe accident (50-247-LR, 50-286-LR).

In early 2014, state Attorney General Eric T. Schneiderman protested a ruling by the commission’s Atomic Safety and Licensing Board approving Entergy’s severe accident mitigation alternatives (SAMA) analysis as part of the company’s application for a 20-year license renewal of Indian Point Units 2 and 3. Both units have been operating under extensions granted by the commission after their licenses expired.

Schneiderman challenged the analysis on several key findings, with the commission siding with his contention that cleanup costs and other economic impacts were underestimated.

“While typically we decline to second-guess the board on its fact-specific conclusions, here the decision contains obvious material factual errors and could be misleading, warranting clarification,” the commission wrote.

In his challenge, Schneiderman said Entergy had relied on generic cost estimates for site cleanup and not a site-specific analysis, as required by the commission. Indian Point is about 40 miles from midtown Manhattan.

The commission agreed. “We find that the SAMA analysis and the board’s decision insufficiently address uncertainty in the Indian Point … inputs — uncertainty shown by New York to have a potential to affect the SAMA analysis cost-benefit conclusions,” it wrote. “We conclude … that the analysis should be buttressed by additional sensitivity analysis.”

“I am heartened that the NRC commissioners agreed with my office that Entergy and NRC staff have systematically undercounted the costs and impacts associated with severe reactor accidents at the Indian Point plant,” Schneiderman said in a statement.

“As part of the standard process for relicensing nuclear power plants, the NRC tasked Indian Point with assessing the economic consequences of the unlikely event of a serious accident,” plant spokesman Jerry Nappi said in a statement. “In our application to renew the plant’s license, we used a model the NRC established for the entire nuclear power industry.”

The ruling comes as New York investigates the plants for several incidents, including a leak of radioactive water. (See NRC: No Further Leakage at Indian Point.)

The “decision by the NRC commissioners to reverse an earlier administrative ruling, and to require a re-examination of the impacts caused by severe accidents at Indian Point and potential upgrades, reaffirms our long-standing position that the aging nuclear power plant needs to be retired,” Gov. Andrew Cuomo, who has frequently criticized the plant, said in a statement.