Running out of space to store water contaminated by fuel that escaped during the Fukushima meltdown, the Japanese government is preparing to release it into the Pacific Ocean – despite the presence of radioactive elements.
Currently, 1.09 million tons of contaminated water is stored in 900 tanks near the Dai-Ichi nuclear plant, which suffered a catastrophic release of fuel following an earthquake and tsunami in March 2011.
The government claims that radioactive material is being reduced to non-detectable levels through the Advanced Liquid Processing System procedure, but there is evidence that this process does not remove many radioactive elements, including antimony, cobalt, iodine, rhodium, ruthenium, strontium, and tellurium. Tepco, which operates the plant, admits the water contains tritium, but insist the levels are “safe.”
The UK Telegraph has obtained documents from Japanese government sources indicating that authorities are aware ALPS, developed by Hitachi, is not actually eliminating radioactive elements to non-detectable levels. Tepco was forced last month to admit that 80 percent of the water still contains radioactive substances after local residents and fishermen protested plans to dispose of it in the ocean.
Tepco admits that 65,000 tons of ALPS-cleansed water retain more than 100 times the amount of strontium-90 legally permitted. Strontium-90 accumulates in teeth and bones and can cause leukemia and bone cancer.
Tritium, too, is not harmless, despite Tepco’s assurances. According to nuclear specialist Shaun Burnie, beta particles of the element are more harmful than X-rays and gamma rays.
The government initially planned to release the contaminated water in 2016, but was surprised by the strength of local opposition. In March 2016, Tepco executives were charged with contributing to deaths and injuries in relation to the Fukushima meltdown after a judicial panel said they had ignored a 2008 internal report warning the plant could be struck by 15-meter waves in the event of a tsunami.
Documents provided to The Telegraph by a source in the Japanese government suggest, however, that the ALPS has consistently failed to eliminate a cocktail of other radioactive elements, including iodine, ruthenium, rhodium, antimony, tellurium, cobalt and strontium.
Hitachi declined to comment on the reports on the performance of its equipment. The Japanese government did not reply to multiple requests for comment.
A restricted document also passed to The Telegraph from the Japanese government arm responsible for responding to the Fukushima collapse indicates that the authorities were aware that the ALPS facility was not eliminating radionuclides to “non-detect” levels. That adds to reports of a study by the regional Kahoko Shinpo newspaper which it said confirmed that levels of iodine 129 and ruthenium 106 exceeded acceptable levels in 45 samples out of 84 in 2017.
Iodine 129 has a half-life of 15.7 million years and can cause cancer of the thyroid; ruthenium 106 is produced by nuclear fission and high doses can be toxic and carcinogenic when ingested.
In late September, Tepco was forced to admit that around 80 per cent of the water stored at the Fukushima site still contains radioactive substances above legal levels after the Ministry of Economy, Trade and Industry held public hearings in Tokyo and Fukushima at which local residents and fishermen protested against the plans.
Tepco has now admitted that levels of strontium 90, for example, are more than 100 times above legally permitted levels in 65,000 tons of water that has been through the ALPS cleansing system and are 20,000 times above levels set by the government in several storage tanks at the site.
Experts agree that the danger posed by any release depends on the concentrations of radionuclides and the subsequent contamination of fisheries products.
The presence of strontium in the bones of small fish that might be consumed by humans could be a cause of major concern. If ingested by humans, strontium 90 builds up in teeth and bones and can cause bone cancer or leukaemia.
Shaun Burnie, a nuclear specialist with Greenpeace, also disputes Tepco’s claims that tritium is effectively harmless.
“Its beta particles inside the human body are more harmful than most X-rays and gamma rays”, he said, adding that there “are major uncertainties over the long-term effects posed by radioactive tritium that is absorbed by marine life and, through the food chain, humans.
“The planned release of billions of becquerels by Tepco cannot be considered an action without risk to the marine environment and human health”.
In 2015, ccientists at the Woods Hole Oceanographic Institution (WHOI) detected the presence of small amounts of radioactivity from the 2011 Fukushima Dai-ichi Nuclear Power Plant accident in a seawater sample from the shoreline of North America. The sample, which was collected on February 19 in Ucluelet, British Columbia, with the assistance of the Ucluelet Aquarium, contained trace amounts of cesium (Cs) -134 and -137, well below internationally established levels of concern to humans and marine life.
The WHOI scientists, with the help of citizen volunteers, have collected samples at more than 60 sites along the U.S. and Canadian West Coast and Hawaii over the past 15 months for traces of radioactive isotopes from Fukushima. Last November, the team reported their first sample containing detectable radioactivity from Fukushima 100 miles (150 km) off shore of Northern California. However, no radiation had yet been found along any of the beaches or shorelines where the public has been sampling since 2013.
“Radioactivity can be dangerous, and we should be carefully monitoring the oceans after what is certainly the largest accidental release of radioactive contaminants to the oceans in history,” said Ken Buesseler, a marine chemist at WHOI who has been measuring levels of radioactivity in seawater samples from across the Pacific since 2011. “However, the levels we detected in Ucluelet are extremely low.”
Scientists at WHOI are analyzing samples for two forms of radioactive cesium that can only come from human sources. Cesium-137, the “legacy” cesium that remains after atmospheric nuclear weapons testing, is found in all the world’s oceans because of its relatively long, 30-year half-life. This means it takes 30 years for one-half of the cesium-137 in a sample to decay. The Fukushima reactors added unprecedented amounts of cesium-137 into the ocean, as well as equal amounts of cesium-134. Because cesium-134 has a two-year half-life, any cesium-134 detected in the ocean today can only have been added recently—and the only recent source of cesium-134 has been Fukushima.
The Ucluelet sample contained 1.4 Becquerels per cubic meter (Bq/m3) (the number of decay events per second per 260 gallons of water) of cesium-134, a telltale sign of having come from Fukushima, and 5.8 Bq/m3 of cesium-137. These levels are comparable to those measured 100 miles off the coast of Northern California last summer. If someone were to swim for 6 hours a day every day of the year in water that contained levels of cesium twice as high as the Ucluelet sample, the radiation dose they would receive would still be more than one thousand times less than that of a single dental x-ray.
Buesseler has had to rely on a crowd-funding and citizen-science initiative known as “Our Radioactive Ocean” to collect samples because no U.S. federal agency is responsible for monitoring radiation in coastal waters. The results are publicly available on the website OurRadioactiveOcean.org.
“We expect more of the sites will show detectable levels of cesium-134 in coming months, but ocean currents and exchange between offshore and coastal waters is quite complex,” said Buesseler, “Predicting the spread of radiation becomes more complex the closer it gets to the coast and we need the public’s help to continue this sampling network.”
James E Windsor, Overpasses News Desk
October 18th, 2018