Officials at Japan's nuclear regulator are angry at the operator of the Fukushima Dianichi nuclear power plant. They say the utility was too slow to find ways to stop contaminated groundwater from seeping into the ocean. Highly radioactive substances have been detected in the plant's monitoring wells near the Pacific Ocean since May. Tokyo Electric Power Company admitted for the first time on Monday that tainted water is leaking into the ocean. Tepco reached the conclusion after analyzing water levels in the wells and comparing them with tide levels. The nuclear regulation authority says Tepco took too long to act. The regulator plans to study ways to locate and stop the leak. Crews at the plant are trying to prevent further leaks. They're injecting chemicals into the soil to solidify it. They're working to create two walls that would be about 14 meters deep and 90 meters long. The walls would be back-to-back and separate the facility from the ocean. Tepco officials say the level of radiation in the area is as high as 200 micro sieverts per hour. Five hours of exposure is equivalent to the annual allowable limit for humans. Crews are wearing protective clothing to guard against the radiation. They do most of the work at night to avoid heat stroke. Officials say the work is scheduled to finish before the middle of next month. Workers at Fukushima Daiichi struggle every day to keep radioactive water from leaking into the environment and HK World's Tsushima Kojima shows us what they're up against. Engineers at Fukushima Daiichi need to keep nuclear fuel inside three damaged reactors cool to avoid another crisis. The pump water into every unit every day. It becomes highly contaminated after being exposed to the fuel. Adding to that problem, groundwater seeps through cracks in the plant. About 400 tons of it gets contaminated every day. Tepco workers have been pumping all the tainted water into storage containers. They dug observation wells along the coast to check if any water they missed was reaching the ocean. Engineers kept saying they didn't have enough data to confirm a leak. But since May, Dave detected high levels of radioactive strontium and tritium in the world. The levels were between 18-30 times higher than the government said standard, allowing contaminated water to be released into the sea. Experts visited the nuclear regulation also to warned in June that the leak was highly possible. If there's a leak into the ocean, Tepco needs to assess the impact it has on marine life. But before that, it needs to monitor very carefully how much contaminated water is leaking. A few weeks later, Tepco managers admitted contaminated groundwater is seeping into the ocean. They said they found the levels of groundwater inside the wells coincided with tidal changes, meaning sea water and groundwater are connected. Now only Tepco workers are monitoring contaminated water near the plant. A scientist who studies ocean radiation levels says that must change. The leak of contaminated materials is not surprising, whether Tepco admits it or not. All of the experts said it was highly likely. The data provided by Tepco doesn't help trace the source of the leak. We have some ideas about how the utility should investigate this problem. We want them to create a new system that allows all of the experts to contribute. It's become increasingly clear that one company can't handle the accident on its own. Experts agree it's time to use all resources available to tackle this problem. The massive tsunami of March 2011 wreaked havoc along the coast of Northeastern Japan, forcing many beaches to close. 11 out of 70 will be opened this year. They include a popular site on an island just 3 kilometers from the earthquake's epicenter. And each of the worlds Akane Nakajima has more. A beach on the island of Ajishima is reopening for the first time in 3 years. Locals participate in a shinto ceremony to pray for a good summer season. A few people brave the chilly weather on this first weekend to take a dip. The area is famous for its crystal clear water and peaceful atmosphere. The water is cool. I'm having so much fun. It feels great. The beach is so clean. It's hard to imagine it used to be a pile of wreckage. Locals have worked hard to install public lavatories just 2 weeks ago and a watchtower just 3 days ago just in time for the reopening. The beaches of Ajishima used to attract around 30,000 visitors every year. They resounded with the shouts of children playing in the water. All back came to an end with the tsunami of March 2011. The entire shore was covered with rubble, driftwood, and broken fishing nets. Residents were concerned about the large amount of debris on the seabed. Everyone young and old participated in a long and painstaking cleanup operation. We cleaned the beach almost every day. We removed things from the water and the shore and threw them away. 13,000 tons of rubble have been removed so far from Ajishima. And after 2 years of efforts, the islanders have finally cleared one of its beaches. Signs mark the directions of escape routes in case of a tsunami. The high grounds allowed all locals to survive 2 and a half years ago. Taurus, who used to visit every year, are starting to come back, learned by the prospect of enjoying the pristine waters of Ajishima. The island was so quiet last summer because no bethers were around. We are very happy to see all the progress we've made this year. We islanders take great pride in the beauty of the ocean. We're thrilled to see visitors coming back to enjoy our magnificent waters, nature, and local cuisine. The islanders still have a long way to go to clean up the entire coastline. But they've made a big first step toward returning their island to its former glory. Akane Nakajima in each K-World, Ajishima. And local officials say the waters around Ajishima pose no risk. They say radiation readings are below the safe element.