FILE PHOTO - A geiger counter measures a radiation level of 54.0 microsievert per hour near the No.2 and No.3 reactor buildings at Tokyo Electric Power Co's (TEPCO) tsunami-crippled Fukushima Daiichi nuclear power plant in Okuma town, Fukushima prefecture, Japan February 18, 2019. REUTERS/Issei Kato

SEOUL (Reuters) - Japan’s reluctance to disclose information about the release of radioactive water from its damaged Fukushima nuclear plant is hampering neighboring countries’ efforts to minimize the impact, the head of South Korea’s nuclear safety agency said on Wednesday.

Since the 2011 earthquake and tsunami caused a meltdown at some of the reactors the Fukushima plant, owner Tokyo Electric Power Co (Tepco) has been storing radioactive water in tanks at the site from the cooling pipes used to keep the fuel cores from melting. The utility will run out of space for the water in 2022.

Japan has not yet decided how to deal with the contaminated water, but its environment minister said in September that radioactive water would have to be released from the site into the Pacific Ocean.

“We have been raising Japan’s radioactive water issue to the international community to minimize the impact ... but as Japan hasn’t disclosed any specific plan and process we would need more details to run simulations and study,” Uhm Jae-sik, chairman of the Nuclear Safety and Security Commission, told Reuters.

In addition to the Fukushima crisis, safety concerns about nuclear energy have increased in South Korea following a 2012 scandal over the supply of faulty reactors parts with forged documents, prompting a series of shutdowns of nuclear reactors.

South Korea, the world’s fifth-largest user of nuclear power, targets a long-term phase out of atomic power to allay public concerns.

“Regardless of the government’s energy policy change, our primary goal is ensuring the safety of nuclear power,” Uhm said.

South Korea operates 25 nuclear reactors, which generate about a third of the country’s total electricity. Of the 25 reactors, 10 are offline for maintenance, according to the website of Korea Hydro & Nuclear Power.

(This story corrects the word “specific” to clarify meaning in translated quote in paragraph 4)