A workers stands in front of an 18-meter (59 ft) high and 1.6 km (1 mile) long tsunami defence wall at Chubu Electric Power Co.'s Hamaoka Nuclear Power Station in Omaezaki, Shizuoka Prefecture May 17, 2013. Chubu Electric is spending at least $1.5 billion on safety upgrades at its Hamaoka nuclear plant southwest of the Japanese capital, to reduce the risk of a repetition of the disaster that hit Tokyo Electric's Fukushima station, when an earthquake and tsunami caused three reactor meltdowns. REUTERS/Toru Hanai (JAPAN - Tags: BUSINESS ENERGY ENVIRONMENT TPX IMAGES OF THE DAY)

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