Thursday, July 21, 2011

Quote of the day

From the Wall Street Journal, July 19, 2011:



TOKYO—Local officials in Fukushima prefecture said on Monday that 411 more cattle potentially contaminated with radioactive cesium have been shipped around Japan, a development sure to fuel food-safety fears.


The prefectural government said the additional beef cattle found to have eaten contaminated rice straw came from seven farms in six municipalities in the prefecture, bringing the total number of potentially contaminated cattle shipped from Fukushima for
consumption to 554. Some of Japan's biggest supermarket chains have sold beef from the cattle.

The local government added that the rice straw had tested at up to 690,000 becquerels per kilogram, more than 500 times the
government's safety limit...

It still isn't clear whether contaminated feed necessarily contaminates beef from the cattle that eat it...

Japanese authorities already said Sunday that they intend to ban cattle shipments from Fukushima prefecture, and possibly wider areas, as more animals have been identified as having consumed feed contaminated with radioactive cesium released from the nuclear power plant.

Besides Fukushima, radioactive cesium-contaminated rice straw has been found in Miyagi prefecture, north of Fukushima, and Niigata prefecture, at farms supplied with Miyagi-produced straw.

The assertion that it isn't clear whether contaminated feed necessarily contaminates the beef from the cattle that eat it echoes the widespread belief that cataclysmic climate change has nothing to do with human activities. The discovery of 690,000 Bq/kg of Cs-137 in rice straw, the peak value in approx. 50 samples, illustrates the unavoidable reality that Fukushima Daiichi-derived radioactive fallout is in the same order of magnitude as that generated by the Chernobyl accident. The Wall Street Journal article provides no information about the testing locations in the Fukushima prefecture where contaminated rice straw has been monitored. The ongoing controversy of contaminated beef highlights the necessity of much more comprehensive monitoring of pathways to human consumption of Fukushima Daiichi-derived contamination, especially of the indicator nuclides I-131, Cs-134, and Cs-137.

TEPCO and NISA monitoring data, available at www.tepco.co.jp, provide ongoing measurement of soil contamination around the Fukushima Daiichi nuclear power station as measured in Bq/kg of soil. Air contamination is measured in microsieverts/hour and indicator nuclides in seawater as measured in Bq/cubic centimeter.

On July 4th, TEPCO reported radiocesium in wet soil on a reactor facility playground at 440,000 Bq/kg, again reflecting Chernobyl order of magnitude deposition levels. The highest air contamination levels on the reactor site are reported near the main building with dose rates on July 21st running between 315 to 333 microsieverts per hour. Other onsite locations reporting radiation dose rates of 30 to 33 microsieverts per hour at the main gate and 12 to 13 microsieverts per hour at the west gate. In contrast, normal background radiation dose rates are 0.27 to 0.7 microsieverts per hour. The radiation dose rate at the main building is about 1/7th of the peak value reported near the administration building on March 21, 2011 of 2,015 microsieverts per hour. TEPCO data, therefore, indicates significant radiation releases from all 7 accident sites are continuing with little or no variation in dose rates. The data reported by TEPCO and NISA graphically illustrate what is not being reported:


  • An ongoing release profile of the emissions from each fuel meltdown site as measured in Bq/hour. This provides much more accurate information about the status of these ongoing releases than ambient radiation dose rates.

  • A correlated emissions release profile consistently lacking in TEPCO monitoring is the measurement of airborne plume activity as expressed in Bq/cubic meter. Typical baseline airborne contamination levels range from 0 to 10 microbequerels per cubic meter. TEPCO reports airborne activity in locations well away from the seven point sources in Bq/cubic centimeter (a reporting unit 1 millionth of a Bequerel per cubic meter). The use of this much smaller reporting unit is a tip off of a major nuclear accident in progress.

  • TEPCO airborne dust nuclide analyses for radiocesium reports radiocesium contamination slightly above 1.0E-05 Bq per cubic centimeter in late May rising slightly in early June before falling in mid-June and rising again in late June. According to the data provided by TEPCO there didn't appear to be any significant drop off of Cs-137 contamination levels in airborne dust before early July, when data is no longer available. The TEPCO data can also be restated as measured in microbequerels per cubic meter, i.e. slightly above 10 microbequerels per cubic meter. This is only slightly above background levels. If this is uniformly the case, why are background radiation dose rates running so high near the main building, and what are the actual background radiation dose rates and emission levels at and above the seven meltdown sites? Obviously more information is needed.

  • Among the most notable deficiencies in TEPCO and NISA monitoring reports are the lack of a comprehensive radiometric survey of Cs-137 deposition levels in all prefectures in Japan. This information would shed much more light on the likely extent of contamination in cattle feed throughout Japan.

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