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The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

there was no large explosive release of core reactor material, so most of the isotopes reported to have spread thus far via atmospheric fallout are primarily the radioactive gases plus fission products such as cesium, which are volatilized at the high temperatures in the reactor core, or during explosions and fires. However, some nonvolatile activation products and fuel rod materials may have been released when the corrosive brines and acidic waters used to cool the reactors interacted with the ruptured fuel rods, carrying radioactive materials into the ground and ocean. The full magnitude of the release has not been well documented, nor is there data on many of the possible isotopes released, but we do have significant information on the concentration of several isotopes of Cs and I in the ocean near the release point which have been publically available since shortly after the accident started.

We present a comparison of selected data made publicly available from a Japanese company and agencies and compare these to prior published radionuclide concentrations in the oceans. The primary sources included TEPCO (Tokyo Electric Power Company), which reported data in regular press releases(3) and are compiled here (Supporting Information Table S1). These TEPCO data were obtained by initially sampling 500 mL surface ocean water from shore and direct counting on high-purity germanium gamma detectors for 15 min at laboratories at the Fukushima Dai-ni NPPs. They reported initially results for 131I (t1/2 = 8.02 days), 134Cs (t1/2 = 2.065 years) and 137Cs (t1/2 = 30.07 years). Data from MEXT (Ministry of Education, Culture, Sports, Science and Technology—Japan) were also released on a public Web site(4) and are based on similar direct counting methods. In general MEXT data were obtained by sampling 2000 mL seawater and direct counting on high-purity germanium gamma detectors for 1 h in a 2 L Marinelli beaker at laboratories in the Japan Atomic Energy Agency. The detection limit of 137Cs measurements are about 20 000 Bq m–3 for TEPCO data and 10 000 Bq m–3 for MEXT data, respectively. These measurements were conducted based on a guideline described by MEXT.(5) Both sources are considered reliable given the common activity ratios and prior studies and expertise evident by several Japanese groups involved in making these measurements. The purpose of these early monitoring activities was out of concern for immediate health effects, and thus were often reported relative to statutory limits adopted by Japanese authorities, and thus not in concentration units (reported as scaling factors above “normal”). Here we convert values from both sources to radionuclide activity units common to prior ocean studies of fallout in the ocean (Bq m–3) for ease of comparison to previously published data.

The Department of Energy and General Electric will spend $2 million over the next two years to remove naturally occurring radioactive materials from the fracking fluids produced by America’s booming shale-gas industry. The New York State Department of Health has identified Radium-226 as a radionuclide of particular concern in the Marcellus Shale formation deep beneath the Appalachian Mountains. In hydraulic fracturing operations, drillers force water and a mixture of chemicals into wells to shatter the shale and free natural gas. The brine that returns to the surface has been found to contain up to 16,000 picoCuries per liter of radium-226 (pdf). The discharge limit in effluent for Radium 226 is 60 pCi/L, and the EPA’s drinking water standard is 5 pCi/L.

Uranium and Radon-222 have also been found in water returning to the surface from deep shale wells. In Pennsylvania, produced water has been discharged into streams and rivers from the state’s 71,000 wells after conventional wastewater treatment but without radiation testing, according to the Pittsburgh Post-Gazette and The New York Times, which drew attention to the radioactive contamination earlier this year after studying internal EPA documents: The documents reveal that the wastewater, which is sometimes hauled to sewage plants not designed to treat it and then discharged into rivers that supply drinking water, contains radioactivity at levels higher than previously known, and far higher than the level that federal regulators say is safe for these treatment plants to handle. via The New York Times

GE’s Global Research lab in Niskayuna, NY has proposed removing radioactive elements from produced waters and brine using a membrane distillation system similar to conventional reverse osmosis, but designed specifically to capture these radioactive materials. GE will spend $400,000 on the project and DOE will supply $1.6 million. The Energy Department announced the project Monday. The process will produce concentrated radioactive waste, which will be disposed of through conventional means, which usually means storage in sealed containers for deep geological disposal. The government is seeking to address environmental concerns without stemming a boom in cheap gas unleashed by hydraulic fracturing, or fracking, in shale formations.

Though nuclear power produces electricity with little in the way of carbon dioxide emissions, it, like other energy sources, is not without its own set of waste products. And in the case of nuclear power, most of these wastes are radioactive.1 Some very low level nuclear wastes can be stored and then disposed of in landfill-type settings. Other nuclear waste must remain sequestered for a few hundred years in specially engineered subsurface facilities; this is the case with low level waste, which is composed of low concentrations of long-lived radionuclides and higher concentrations of short-lived ones. Intermediate and high-level waste both require disposal hundreds of meters under the Earth’s surface, where they must remain out of harm’s way for thousands to hundreds of thousands of years (IAEA, 2009). Intermediate level wastes are not heat-emitting, but contain high concentrations of long-lived radionuclides. High-level wastes, including spent nuclear fuel and wastes from the reprocessing of spent fuel, are both heat-emitting and highly radioactive.

When it comes to the severity of an accident at a nuclear facility, there may be little difference between those that occur at the front end of the nuclear power production and those at the back end: An accident involving spent nuclear fuel can pose a threat as disastrous as that posed by reactor core meltdowns. In particular, if spent fuel pools are damaged or are not actively cooled, a major crisis could be in sight, especially if the pools are packed with recently discharged spent fuel.

Elements of success

Waste water discharged into Tokyo Bay from a cement plant has been found to contain radioactive cesium at much higher levels than the government-set limit for disposal. The plant in Chiba Prefecture, east of Tokyo, uses ash from incinerators in the prefecture to produce cement. The Chiba government says the plant operator checked waste water discharged from the plant into Tokyo Bay once in September and once in October. It found radioactive cesium at levels of 1,103 becquerels per kilogram, and 1,054 becquerels per kilogram respectively. The levels are 14 to 15 times higher than the limit set by the country's Nuclear Safety Commission. The water had been used to clean filters which remove toxic materials from ashes. The operator stopped discharging the waste water on Wednesday. The prefectural government has launched a survey of the seawater of Tokyo Bay

ScienceDaily (July 3, 2010) — after Fukushima, it is now imperative to redefine what makes a successful nuclear energy–from the cradle to the grave. If the management of nuclear waste is not considered by the authority, the public in many countries reject nuclear energy as an option, according to a survey appearing in the Bulletin of Atomic Scientists, published by SAGE.

According to Allison Macfarlane, Associate Professor of environmental science and policy at George Mason University and a member of the Blue Ribbon for nuclear future of America, resulting in storage for nuclear waste, which is still a last-minute decision to a number of countries outside of Japan. It is surprisingly common for reactor sites for overburdened with spent nuclear fuel without any clear plan. In South Korea, for example, saving to four nuclear power stations in the nation is filled, leading to a crisis within the storage potential of the next decade.

United Arab Emirates broke the ground for the first of four nuclear reactors on 14 March 2011, but has not set the precedence of storage. Hans Blix, former head of the International Atomic energy Agency and current President of the UAE’S International Advisory Council, noted: “it is still an open question of a draft final disposal and greater attention should be spent on deciding what to do.”

Ground soil of rivers. Otsugawa  (Kashiwa Chiba) 9,000 Bq/Kg ← Double from last November. Imba discharge channel (Yachiyo Chiba) 7,800 Bq/Kg ← Double from last November. Mamagawa (Ichikawa Chiba) 4,700 Bq/Kg← 10 times much as last year. (430 Bq/kg)

A nuclear plant in Plymouth has been shut down after a suspected leak from the one of the plants safety relief valves. “An Nuclear Regulator Commission Resident Inspector was at the the Pilgrim nuclear power plant Monday to monitor the shutdown, which took place without any complications,” said Nuclear Regulator Commission spokesman Neil Sheehan. The Nuclear Regulator Commission says the Pilgrim nuclear power plant was shut down due to leakage from a valve which provides overpressure protection for the plant’s reactor coolant system. The NRC, in a statement said the valve opens when required, “to discharge reactor steam into the suppression pool, a large, donut-shaped reservoir of water located at the bottom of the reactor building.” NRC inspectors will also monitor the repairs to the valve and then also monitor the service restoration when the plans are completed.

Japan will seek to halve the amount of radiation in residential areas around the Fukushima No. 1 nuclear plant and cut children's daily radiation dose by 60 percent over the next two years, according to an emergency decontamination policy document.

The plan is to be endorsed Friday by a government task force dealing with the nuclear crisis triggered by the March 11 earthquake and tsunami

The government under the plan will take responsibility for securing final disposal sites for contaminated soil but will stress the need for temporarily storage locally.

You’ve likely heard this argument before: “The wind doesn’t always blow and the sun doesn’t always shine, so we can’t rely on renewable energy.” However, a series of recent events undermine the false dichotomy that renewable energies are unreliable and that coal, nuclear and natural gas are reliable.

There are too many reasons to list in a single blogpost why depending on fossil and nuclear energies is dangerous, but one emerging trend is that coal, natural gas and even nuclear energy are not as reliable as they are touted to be. Take for instance the nuclear disaster still unfolding in Japan. On March 11, that country experienced a massive earthquake and the resulting tsunami knocked out several nuclear reactors on the coast. Three days later, an operator of a nearby wind farm in Japan restarted its turbines - turbines that were intentionally turned off  immediately after the earthquake. Several countries, including France and Germany, are now considering complete phase-outs of nuclear energy in favor of offshore wind energy in the aftermath of the Japanese disaster. Even China has suspended its nuclear reactor plans while more offshore wind farms are being planned off that country’s coast.

In another example much closer to home, here in the Southeast, some of TVA’s nuclear fleet is operating at lower levels due to extreme temperatures. When the water temperatures in the Tennessee River reach more than 90 degrees, the TVA Browns Ferry nuclear reactors cannot discharge the already-heated power plant water into the river. If water temperatures become too high in a natural body of water, like a river, the ecosystem can be damaged and fish kills may occur. This problem isn’t limited to nuclear power plants either.

Arusha. Adequate safety measures must be taken before the start of uranium mining in the country, experts observed here yesterday.They said Tanzania was still short of qualified personnel to handle radioactive materials as well as the requisite infrastructure for storage and transportation of uranium and its by products."Measures have to be taken because accidents involving nuclear material are quite lethal," said the director of Nuclear Technology with the Tanzania Atomic Energy Commission (Taec) Mr Firmin Banzi.Speaking to reporters at  the  start of a training course on radiation detection for the police and security officers from public institutions, the official said mishandling of radiation material was equally deadly. He said strict measures on safety would be put in place before any company is licensed to mine uranium found in some parts of the country.He added that an aggressive public sensitisation has been undertaken for communities living around the Mkuju River valley in Ruvuma Region and Bahi District in Dodoma where large deposits of uranium have been found.Mr Banzi explained that if not handled properly the radioactive uranium would expose people to life-threatening hazards and would as well have long-term effects on the environment and water through contamination.

He emphasized that once uranium mining starts, the security organs in the country must be extra vigilant against people who might steal the radiation material for bad motives such as terrorism."We are living in the world of conflicts. Radioactive material could be used as weapons of mass destruction, revenge and/or sabotages to fulfil political gains or individuals," he pointed out.According to him, the consequences of uncontrolled use of radioactive materials, especially during spillage or discharge, are many including water, food, air and environmental contamination.The week-long course at a hotel in Arusha is being attended by security officers drawn from the Intelligence Department, the police, Criminal Investigation Department, major airports, ports as well as some border posts.The official stressed that since nuclear material has to be handled with care, the relevant experts must keep abreast with the technology trends underlined by the nuclear security programme of the International Atomic Energy Agency, the global watchdog on the radiation matter

Radioactive tritium has leaked from three-quarters of U.S. commercial nuclear power sites, often into groundwater from corroded, buried piping, an Associated Press investigation shows.

The number and severity of the leaks has been escalating, even as federal regulators extend the licenses of more and more reactors across America. Tritium, which is a radioactive form of hydrogen, has leaked from at least 48 of 65 sites, according to U.S. Nuclear Regulatory Commission records reviewed as part of the AP's yearlong examination of safety issues at aging nuclear power plants. Leaks from at least 37 of those facilities contained concentrations exceeding the federal drinking water standard — sometimes at hundreds of times the limit.

While most leaks have been found within plant boundaries, some have migrated offsite. But none is known to have reached public water supplies. STORY: Regulators weaken safety standards for nuclear reactors At three sites — two in Illinois and one in Minnesota — leaks have contaminated drinking wells of nearby homes, the records show, but not at levels violating the drinking water standard. At a fourth site, in New Jersey, tritium has leaked into an aquifer and a discharge canal feeding picturesque Barnegat Bay off the Atlantic Ocean.

On May 30, 2011, KAPS 2 was operating at 98% of full power. Shielding blocks had been removed from the SFTD for the purposes of carrying out a painting job. A radiological work permit was issued for the painting job after taking clearance from the engineer-in-charge of refuelling operations. This permit was issued to carry out painting work between 9.15am and 1.00pm hrs in the SFTD area. Control room staff were instructed not to transfer any spent fuel during this period. However, at around 12.00pm, a refuelling operator in the control room inadvertently discharged a pair of spent fuel bundles to SFSB through SFTD after refuelling. Four workers who were carrying out the painting got exposed to radiation and received 90.72 mSv, 66.81 mSv & 58.70 mSv, and 23.23 mSv radiation dose. The radiation doses to the workers were higher than the prescribed annual regulatory limit stipulated by Atomic Energy Regulatory Board (AERB).

Six months after the nuclear meltdowns in Fukushima Prefecture, the public's awareness of the threat posed by radiation is entering a new phase: the realization that the biggest danger now and in the future is from contaminated soil.

The iodine-131 ejected into the sky by the Fukushima No. 1 power station disaster was quickly detected in vegetables and tap water — even as far away as Tokyo, 220 km south of the plant. But contamination levels are now so low they are virtually undetectable, thanks to the short half-life of iodine-131 — eight days — and stepped up filtering by water companies.

But cesium is proving to be a tougher foe. The element's various isotopes have half-lives ranging from two to 30 years, generating concern about the food chain in Fukushima Prefecture, a predominantly agricultural region, as the elements wash fallout into the ground. The root of the problem is, well — roots. Cesium-134 and cesium-137 are viewed as potential health threats because vegetables can absorb the isotopes from the soil they're planted in.

An increase in anti-nuclear sentiment after the Fukushima disaster in Japan in March has stalled India's ambitious plan for nuclear expansion. The plan, pushed forward by Prime Minister Manmohan Singh, aims to use reactors imported from the United States, France and Russia to increase the country's nuclear-power capacity from the present 4,780 megawatts to 60,000 megawatts by 2035, and to provide one-quarter of the country's energy by 2050. But now there are doubts that the targets will ever be met if safety fears persist.

Officials say that safety precautions are sufficient to make the proposed reactors, some of which are to be sited along the coasts, immune to natural disasters. But protesters are not listening. In April, violent protests halted construction in Jaitapur in the western state of Maharashtra, where Parisian company Areva is expected to build six 1,650-megawatt European Pressurized Reactors. In August, West Bengal state refused permission for a proposed 6,000-megawatt 'nuclear park' near the town of Haripur, which was slated to host six Russian reactors. The state government said that the area is densely populated, and the hot water discharged from the plants would affect local fishing.

On 19 September, following hunger strikes by activists from the People's Movement Against Nuclear Technology, the chief minister of Tamil Nadu state asked Prime Minister Singh to halt work at Koodankulam, about 650 kilometres south of Chennai, where Russia's Atomstroyexport is building two reactors and plans to build four more.

SOURCE: Tepco Starts To Eject Hydrogen From Fukushima Plant -Kyodo, Dow Jones Newswires October 08, 2011 Tokyo Electric Power Co., operator of the crisis-hit Fukushima Daiichi nuclear plant, said Saturday it has started to discharge hydrogen with high concentration levels from a pipe connected to a reactor containment vessel at the plant, as a measure to prevent an explosion. The utility said it has injected nitrogen into the pipe for the No. 1 reactor vessel to eject hydrogen found with high density of more than 60%. The hydrogen has been generated by radiation that dissolved water. [...]