(TOKYO) -- The operator of Japan's Hamaoka nuclear power plant agreed to temporarily shut down three reactors Monday, amid rising concerns about their ability to withstand a powerful earthquake and tsunami.
The decision came days after Prime Minister Naoto Kan urged Chubu Electric, Japan's third-largest power producer, to halt the plant's operations, citing a government study that forecast a magnitude 8.0 quake hitting the Hamaoka area in the next 30 years.
The aging plant located in Shizuoka, 125 miles southwest of Tokyo, sits on an active earthquake fault where nearly 80,000 people live within a six-mile radius.
Safety activists have long questioned Hamaoka's inability to protect its reactors from large waves, but those concerns have grown louder since a magnitude 9.0 earthquake and a tsunami devastated the northeast coast, crippling reactors at the Fukushima Daiichi nuclear plant.
Chubu Electric currently relies on sand dunes to block waves, and has said it would take a few years to build a seawall.
"We understand that the prime minister's request is based on increased concerns over nuclear power in the wake of the Fukushima Daiichi nuclear power plant accident," said Chubu Electric president Akihisa Mizuno at a news conference.
Nuclear energy provides more than one-third of Japan's electricity, with Hamaoka's three reactors accounting for more than 10 percent of Chubu's power supply.
Shutting down the plant is likely to further strain the country's energy supply, already hurting from the nuclear disaster at the Fukushima plant.
Hamaoka supplies power to about 16 million people in regions that include Aichi, home to Toyota Motor Corps.
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