On January 15, the Tohoku Electric Power Co. submitted a written opinion to Nuclear Regulation Authority (NRA) objecting to a draft evaluation report issued on December 22 by an NRA expert panel concerning a fault zone of crushed rock at the Higashidori Nuclear Power Station (NPS), owned and operated by the power company. The written opinion made individual objections to the points contained in the NRA report.

In its report, the NRA panel had said that fault zone f-2, located immediately below the reactor building, was not one that could possibly to be active in the future. However, it took a different position on the f-1 fault zone, located immediately below important seismic-safety related equipment, and on D-3 and F-9, major faults on the NPS premises.

Pointing that out, Tohoku Electric Power asked the NRA for a full evaluation that would take its submitted opinion into consideration.