International Atomic Energy Agency (IAEA) experts on Thursday began studying radiation monitoring activities conducted by Japanese authorities and the plant operator in seawater near the crippled Fukushima Daiichi nuclear power plant. The two researchers from the IAEA Environment Laboratories in Monaco left Onahama port in Fukushima Prefecture in the morning by ship to test samples of seawater surrounding the plant and analyze them for radioactive materials. The two experts came to Japan at the request of the Japanese government to prepare for the IAEA's decommissioning mission, which will be dispatched later this month, according to the Japanese Nuclear Regulation Authority (NRA). The researchers are also scheduled to discuss the marine monitoring with Japanese authorities, including the NRA, and conduct detailed hearings on the marine monitoring from those authorities during their stay in Japan till November 12. The IAEA is expected to make full use of the findings of the monitoring to help plant operator Tokyo Electric Power Co. (TEPCO) to decommission the four damaged reactors, according to the NRA. TEPCO has been struggling over the months to keep the massive amount of radiation-tainted water from seeping out from storage tanks in the complex, with some believed reach the Pacific Ocean. Seawater monitoring by Japanese authorities and TEPCO has shown that radioactivity levels in most examined sea areas are under detection limits, but concerns about sea water safety have been growing among neighboring countries due to repeated leaks of contaminated water. IAEA Director General Yukiya Amano told the NRA last month that it is crucial that Japan share data with the international society to address such concerns. In September, South Korea banned imports of marine products from Fukushima and seven other prefectures. The magnitude-9.0 quake and subsequent Tsunami in March 2011 hit the Fukushima plant, located 230km north of Tokyo, knocking out its vital cooling systems of three reactors. It resulted in explosions, fires and the worst radiation crisis since the 1986 Chernobyl catastrophe.