ISTANBUL

The powerful New Year's Day earthquake has inflicted “stress” beyond design limit on the Shika nuclear power plant as an expert has called it a “huge problem” that radiation levels around the plant had not been monitored.

The two reactors of the facility were already taken off long before the magnitude 7.6 tremor, designated as a "disaster of extreme severity" by the government, hit Japan at around 4.10 p.m. (0710GMT) on Jan. 1 in Ishikawa province.

The epicenter of the earthquake was the Noto Peninsula, where the plant is located, in the province facing the Sea of Japan. The quake killed at least 213 people, while 52 others are still missing. Thousands of people are still being evacuated to safer places.

A report by Japan’s Nuclear Regulation Authority “indicated the potentially alarming readings of ground acceleration did not appear to pose an immediate safety threat” to the plant, Tokyo-based Kyodo News reported on Thursday.

The authority found that the quake had inflicted “stress on parts of a local nuclear power plant that exceeded the limit anticipated in the facility's design.”

At a meeting on Wednesday, Nobuhiko Ban, a member of the authority panel and expert on protection from radiation exposure, called it “a huge problem that real-time radiation levels have not been monitored at some locations” around the nuclear plant following the earthquake.

He proposed that aircraft and drones should be used to monitor radiation levels.

The Hokuriku Electric Power Company, which operates the plant, twice reported oil leak around the transformer of the No. 2 reactor.

Shinsuke Yamanaka, head of the nuclear regulator, said: “The activity in undersea faults which triggered the latest quake must be factored in as new knowledge in updating safety standards.”

The plant operator was asked “to get to the bottom of a breakdown” of electric transformers installed at the plant which has prevented electricity supply from outside the plant.

The Hokuriku company said, “The plant can keep cooling used fuels after the latest quake.”

Earlier, the operator had said the water level around the Shika nuclear power plant rose by around three meters (10 feet) following the massive earthquake.

A four-meter-high (13-feet-high) seawall “installed to protect the No. 1 reactor was tilting by several centimeters,” the operator had found.