Since March of , an estimated 1, gallons of waste have leaked from B, which the department has been tracking for over a year.
Randy Bradbury, a department spokesman, told CBS News his agency recognized the tank's liquid level was decreasing more than a year ago but they weren't sure of the cause. But on Thursday, the U. Department of Energy notified the Washington agency that the tank was indeed leaking. After the leak was discovered by a contractor, the Department of Energy sent a message Thursday to Hanford Site employees saying the tank had been "previously emptied of pumpable liquids, leaving a very small amount of liquid waste in the tank.
The Hanford Nuclear Reservation, which was constructed during World War II to make plutonium for nuclear weapons, includes tanks that contain various mixed waste materials made of both radioactive components and some of the "most dangerous waste created over four decades," according to Washington's Department of Ecology.
In the past, more than 67 tanks at the reservation have been suspected to be leaking or have actually leaked. An environmental impact statement from the National Environmental Policy Act said that "numerous geologic problems with the Hanford Reservation have been pointed out. In a study , Jota Kanda, an oceanographer at Toyko University of Marine Science and Technology, calculated that the plant is leaking 0. For a comparison, the atomic bomb dropped on Hiroshima released 89 terabecquerels of cesium when it exploded.
Another potential worry: The makeup of the radioactive material being leaked by the plant has changed. Buesseler said the initial leak had a high concentration of cesium isotopes, but the water flowing from the plant into the ocean now is likely to be proportionally much higher in strontium, another radioactive substance that is absorbed differently by the human body and has different risks.
The tanks on the plant site have times more strontium than cesium, Buesseler said. He believes that the cesium is retained in the soil under the plant, while strontium and tritium, another radioactive substance, are continuing to escape. Related: " Japan's Nuclear Refugees ". There are at least a couple of possibilities. In an effort to cool and control the damaged reactors, TEPCO has pumped enormous amounts of water in and out.
But that water is contaminated with radioactive material, and it has to go someplace. According to a recent report issued by the International Atomic Energy Agency, the plant operator has been storing highly contaminated water in seven underground storage ponds, which have a total of 60, tons But most experts seem to think that ordinary movement of groundwater probably is the real culprit.
Keeping that water from continuing to flow into the ocean is crucial. As the IAEA noted in its report, "the accumulation of enormous amounts of liquids due to the continuous intrusion of underground water into the reactor and turbine buildings is influencing the stability of the situation.
Nuclear Regulatory Commission. It built a groundwater bypass system, which tries to siphon off and reroute groundwater flowing down from the mountain side of the complex, before it can get into the basements of the reactor buildings and be contaminated.
Plant workers also tried to create an underground barrier by injecting chemicals into the soil to solidify the ground along the shoreline of the Unit 1 reactor building. Officials also believe the water is rising to the surface, which is a troubling development because it could hasten leakage into the sea. Unfortunately, TEPCO must deal with an ever-increasing amount of contaminated water—nearly , tons According to New Scientist, the new system supposedly can filter out 62 different radioactive substances.
However, the April IAEA report noted that the filtering system is still a work in progress, and that in tests so far, "it has not accomplished the expected result" in terms of removing radioactive material from the water. The Wall Street Journal recently reported that TEPCO hopes eventually to be able to discharge the cleansed water into the ocean, though that plan would likely meet intense opposition from local fishermen.
In a July 26 press release , TEPCO also said it would continue construction of a shielding wall along the waterline, but that structure will not be finished until September The initial gigantic deluge of contaminated water dispersed through the immediate Fukushima coastal area very quickly, according to a report by the American Nuclear Society.
But it takes years for the contamination to spread over a wider area. A mathematical model developed by Changsheng Chen of the University of Massachusetts at Dartmouth and Robert Beardsley of the Woods Hole Oceanographic Institute found that radioactive particles disperse through the ocean differently at different depths.
The scientists estimated that in some cases, contaminated seawater could reach the western coast of the United States in as little as five years. Buesseler thinks the process occurs a bit more rapidly, and estimates it might take three years for contamination to reach the U.
Susanne Rust is an award-winning investigative reporter specializing in environmental issues. She is based in the Bay Area. After a series of stormy superlatives, California settles back into a more seasonable pattern. California rains break all-time records, spurring floods and mudslides. California rainstorm drenches L.
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