A large oil spill from a wrecked Russian tanker is approaching Wakasa Bay, along which a number of nuclear power plants are located, the Maritime Safety Agency announced Jan. 10.Seawater is used in the plants to cool the steam from the power-generating turbines and the slick could force the nuclear plants to shut down operations. The agency has dispatched about 50 patrol ships and fishing boats to closely monitor the oil in the bay, officials said.The national government established a headquarters Jan. 10 within the Transport Ministry, headed by Transport Minister Makoto Koga, to deal with the oil spill from the wrecked Russian tanker Nakhodka. The headquarters, composed of the minister and 15 senior officials from related ministries and agencies, will evaluate the situation and act to strengthen disaster relief measures, Koga told a news conference after the day's regular Cabinet meeting."First of all, we must stop the oil spill," he said. "Then, we must thoroughly discuss various issues from fishing to environmental problems."The slick threatening Wakasa Bay measures 13 km by 12 km. It was spotted about 8 km north of Maizuru, Kyoto Prefecture, and is moving in southeast toward the bay. The vessels from the MSA and local fishery cooperatives are preparing to spray neutralizing agents on the slick and place oil fences near the nuclear power plants. Power plant workers have already started spreading oil nets around feed water outlets at the facilities, they said.Meanwhile, Japan has urged Russia to conduct a thorough investigation into the sinking of the tanker and implement measures to prevent a recurrence of a similar accident, Foreign Ministry officials said Jan. 10. The requests were formally made late Jan. 9 in Moscow by Ambassador Takehiro Togo to Russian Foreign Vice Minister Viktor Posuvalyuk, the officials said.Pointing out that the Japanese public is concerned about the accident, Togo told Posuvalyuk that the Japanese government has a strong interest in why such an accident occurred and what kind of measures the Russian government will implement to prevent a recurrence, the officials said. Posuvalyuk expressed deep regret over the accident, the officials said. He also expressed appreciation for Japan's prompt rescue of the tanker's crew, they said. Togo called for continued cooperation by Russia to collect the spilled fuel oil, the officials said.On Jan. 9, Russian President Boris Yeltsin expressed his "heartfelt gratitude" to Japan for saving the lives of 31 members of the Nakhodka's crew. The captan of the vessel is still missing. On Jan. 10, the owner of the tanker apologized for the accident and pledged compensation.