Radiation monitoring in Japan

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Radiation levels in Japan are continuously monitored in a number of locations, and a large number stream their data to the internet. Some of these locations are mandated by law for nuclear power plants and other nuclear facilities. Some of them serve as part of a national monitoring network for use in a nuclear emergency. Others are independent monitoring stations maintained by individuals.

Contents

Interest in the levels of radiation all over the nation increased dramatically during the Fukushima I nuclear accidents. At that time, a number of people began streaming from monitoring stations, and some international organizations conducted special monitoring operations to assess the state of radiation levels near the power plant and throughout Japan.

Monitoring at Nuclear Power Plants

Regulations per the Japanese Nuclear Safety Commission prescribe some standards that a monitoring system at a power producing nuclear plant must adhere to. For the purposes of regulation, monitoring systems are divided into two categories.

Additionally, a condition for both categories is that it have the ability to monitor continuously and record its results. [1]

During normal operation, plants have to monitor gas and liquid radioactive effluent releases. The only type that requires continuous monitoring is radioactive noble gasses, although some require monitoring only for every discharge. Other types of radiation must be monitored weekly or monthly according to the regulations. [2]

Operating power plant sites stream readings from environmental radiation detectors located around or on periphery of the site, detectors measuring radiation levels leaving the plant stack (gaseous effluents), and detectors monitoring the radiation of the discharged waste heat water. Official monitoring websites of nuclear power plants in Japan are listed below.

Monitoring Organizations and Individuals

Radiation monitoring in Japan is performed and publicly streamed by a number of governmental agencies and non-governmental organizations and individuals.

SPEEDI Network

The Nuclear Safety Division of the Ministry of Education, Culture, Sports, Science and Technology streams information from a national network of detectors, called the System for Prediction of Environment Emergency Dose Information (SPEEDI). It has been called a "computer-based decision support system" by researchers, and its function is for real-time dose assessment in radiological emergencies. In 1993 it had been developed for domestic local range accidents and was in the process to scale up to a national scale emergency response program linked to local governments. A worldwide version (WSPEEDI) was under development. [3]

Use in Fukushima Daiichi nuclear disaster

The government recommendation that people voluntarily evacuate from places in the 20–30 km range from the Fukushima Daiichi plant came after the Nuclear Safety Commission watchdog released forecasts based on SPEEDI measurements. It was found that radiation levels differed significantly based on geography and wind direction, and it was suggested that because of this, the way evacuation areas were being designated should be changed and become more detailed. The Yomiuri Shinbun calculated radiation doses based on data from the Fukushima prefectural government and found they corresponded with the forecasts. [4]

SPEEDI figured in controversy surrounding the Japanese government's use of the data and its failure to use it in planning evacuation routes. Data on the dispersal of radioactive materials were provided to the U.S. forces by the Japanese Ministry for Science a few days after March 11; however, the data was not shared with the Japanese public until March 23. According to Watanabe's testimony before the Diet, the US military was given access to the data "to seek support from them" on how to deal with the nuclear disaster. Although SPEEDI's effectiveness was limited by not knowing the amounts released in the disaster, and thus was considered "unreliable", it was still able to forecast dispersal routes and could have been used to help local governments designate more appropriate evacuation routes. [5]

Ishikawa Lab, Hino, Tokyo

Following the Fukushima disaster, a lab in Hino Tokyo received major attention after a researcher streamed readings from a Geiger counter on his website. [6]

Pachube

The Pachube (pronounced Patch bay) site allows users to stream various sensor data to the web in real time and was put to use for monitoring radiation by a large number of users after March 2011. There was only 1 location streaming into Pachube before the accident, but a large number have since started to stream to the site. The community has converged on a standard way to report the information in order to disseminate the large variety of sources, such as detector model. [7]

The manager of developer relations at Pachube said that he foresaw a range of applications of the data, including cell phone applications. He also noted that the sensors will allow people to cross-check readings for accuracy and could inspire healthy skepticism. Pachube has hundreds of Geiger counters streaming, but there are still concerns that these may not be dense enough. [8]

In 2012 Pachube was acquired by Cosm which in 2013 was renamed xively.

DataPoke Foundation

The privately operated non-profit organization, DataPoke Foundation, performed independent monitoring of the Fukushima Daiichi NPP contamination dispersion. The project, Project:Fukushima, focuses on publicly publishing data, observations, measurements and dispersion plots of the Fukushima NPP contamination, and aggregating public opinion of these observations in order to reach a more complete understanding of the Fukushima Daiichi NPP catastrophe. [9]

RDTN / Safecast

The RDTN.org began as an early crowd-sourcing initiative to sponsor and assist in gathering, monitoring and disseminating radiation data from the affected areas. [10] RDTN intended their independent measurements to provide additional context for the radiation data reported by the official factors, to supplement and not to replace the data of the competent authorities. [11] RDTN successfully launched a micropatronage campaign to raise $33,000 in order to buy 100 Geiger counters to jumpstart their network. [12] In April hackers at tokyohackerspace prototyped an Arduino-based geiger counter shield to upload data from geiger counters including from RDTN supplied counters. [13] This prototype later developed into Safecast mobile geo-tagged radiation sensors. RDTN people attributed their success to crisis urgency. [14] [15] In late April, one month after its start, RDTN folded itself into Safecast with the joint announcement that RDTN was rebranded as Safecast, [16] [17] a citizens' network which continues monitoring radiation levels in Japan.

Related Research Articles

<span class="mw-page-title-main">Nuclear and radiation accidents and incidents</span> Severe disruptive events involving fissile or fusile materials

A nuclear and radiation accident is defined by the International Atomic Energy Agency (IAEA) as "an event that has led to significant consequences to people, the environment or the facility." Examples include lethal effects to individuals, large radioactivity release to the environment, or a reactor core melt. The prime example of a "major nuclear accident" is one in which a reactor core is damaged and significant amounts of radioactive isotopes are released, such as in the Chernobyl disaster in 1986 and Fukushima nuclear disaster in 2011.

<span class="mw-page-title-main">Radioactive contamination</span> Undesirable radioactive elements on surfaces or in gases, liquids, or solids

Radioactive contamination, also called radiological pollution, is the deposition of, or presence of radioactive substances on surfaces or within solids, liquids, or gases, where their presence is unintended or undesirable.

<span class="mw-page-title-main">Kawauchi, Fukushima</span> Village in Tōhoku, Japan

Kawauchi is a village located in Fukushima Prefecture, Japan. As of 1 January 2020, the village had an official registered population of 1,861, and a population density of 9.5 persons per km². The total area of Kawauchi is 197.35 square kilometres (76.20 sq mi). The village was evacuated as a result of the 2011 Fukushima Daiichi nuclear disaster, but in 2014, all restrictions were lifted. It is located in Futaba district

<span class="mw-page-title-main">Namie, Fukushima</span> Town in Tōhoku, Japan

Namie is a town located in Fukushima Prefecture, Japan. As of 29 February 2020 the town has a population of 1,238 in 794 households, although the official registered population was 17,114 in 6853 households. The total area of the town is 223.14 square kilometres (86.15 sq mi). The town was evacuated as a result of the Fukushima Daiichi nuclear disaster—being directly downwind from the power plant—and was within the exclusion zone set up in response to the disaster. Following ongoing clean-up efforts, Namie's business district and town hall have reopened, but access to more heavily contaminated western parts of the town remains restricted.

<span class="mw-page-title-main">Nuclear safety and security</span> Regulations for uses of radioactive materials

Nuclear safety is defined by the International Atomic Energy Agency (IAEA) as "The achievement of proper operating conditions, prevention of accidents or mitigation of accident consequences, resulting in protection of workers, the public and the environment from undue radiation hazards". The IAEA defines nuclear security as "The prevention and detection of and response to, theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving nuclear materials, other radioactive substances or their associated facilities".

<span class="mw-page-title-main">Fukushima Daiichi Nuclear Power Plant</span> Disabled nuclear power plant in Japan

The Fukushima Daiichi Nuclear Power Plant is a disabled nuclear power plant located on a 3.5-square-kilometre (860-acre) site in the towns of Ōkuma and Futaba in Fukushima Prefecture, Japan. The plant suffered major damage from the magnitude 9.1 earthquake and tsunami that hit Japan on March 11, 2011. The chain of events caused radiation leaks and permanently damaged several of its reactors, making them impossible to restart. The working reactors were not restarted after the events.

<span class="mw-page-title-main">Fukushima nuclear accident</span> 2011 nuclear disaster in Japan

The Fukushima nuclear accident was a major nuclear accident at the Fukushima Daiichi nuclear power plant in Ōkuma, Fukushima, Japan which began on 11 March 2011. The proximate cause of the accident was the 2011 Tōhoku earthquake and tsunami, which resulted in electrical grid failure and damaged nearly all of the power plant's backup energy sources. The subsequent inability to sufficiently cool reactors after shutdown compromised containment and resulted in the release of radioactive contaminants into the surrounding environment. The accident was rated seven on the International Nuclear Event Scale by Nuclear and Industrial Safety Agency, following a report by the JNES. It is regarded as the worst nuclear incident since the Chernobyl disaster in 1986, which was also rated a seven on the International Nuclear Event Scale.

<span class="mw-page-title-main">Timeline of the Fukushima nuclear accident</span> Chronology of events following the 2011 Fukushima nuclear disaster

Fukushima Daiichi is a multi-reactor nuclear power site in the Fukushima Prefecture of Japan. A nuclear disaster occurred there after a 9.0 magnitude earthquake and subsequent tsunami on 11 March 2011. The earthquake triggered a scram shut down of the three active reactors, and the ensuing tsunami crippled the site, stopped the backup diesel generators, and caused a station blackout. The subsequent lack of cooling led to explosions and meltdowns, with problems at three of the six reactors and in one of the six spent-fuel pools.

<span class="mw-page-title-main">Radiation effects from the Fukushima Daiichi nuclear disaster</span> Effects of radiation released from the Fukushima nuclear disaster

The radiation effects from the Fukushima Daiichi nuclear disaster are the observed and predicted effects as a result of the release of radioactive isotopes from the Fukushima Daiichii Nuclear Power Plant following the 2011 Tōhoku 9.0 magnitude earthquake and tsunami. The release of radioactive isotopes from reactor containment vessels was a result of venting in order to reduce gaseous pressure, and the discharge of coolant water into the sea. This resulted in Japanese authorities implementing a 30-km exclusion zone around the power plant and the continued displacement of approximately 156,000 people as of early 2013. The number of evacuees has declined to 49,492 as of March 2018. Radioactive particles from the incident, including iodine-131 and caesium-134/137, have since been detected at atmospheric radionuclide sampling stations around the world, including in California and the Pacific Ocean.

<span class="mw-page-title-main">Japanese reaction to Fukushima nuclear accident</span> Japanese reaction to the Fukushima nuclear disaster

The Japanese reaction occurred after the Fukushima Daiichi nuclear disaster, following the 2011 Tōhoku earthquake and tsunami. A nuclear emergency was declared by the government of Japan on 11 March. Later Prime Minister Naoto Kan issued instructions that people within a 20 km (12 mi) zone around the Fukushima Daiichi nuclear plant must leave, and urged that those living between 20 km and 30 km from the site to stay indoors. The latter groups were also urged to evacuate on 25 March.

When the Fukushima Daiichi nuclear disaster began on 11 March 2011, reactor unit 4, 5 and 6 were all shut down. An explosion damaged unit 4 four days after the 2011 Tōhoku earthquake and tsunami. Damages from the earthquake and tsunami on unit 5 and 6 are relatively minor.

The Fukushima disaster cleanup is an ongoing attempt to limit radioactive contamination from the three nuclear reactors involved in the Fukushima Daiichi nuclear disaster that followed the earthquake and tsunami on 11 March 2011. The affected reactors were adjacent to one another and accident management was made much more difficult because of the number of simultaneous hazards concentrated in a small area. Failure of emergency power following the tsunami resulted in loss of coolant from each reactor, hydrogen explosions damaging the reactor buildings, and water draining from open-air spent fuel pools. Plant workers were put in the position of trying to cope simultaneously with core meltdowns at three reactors and exposed fuel pools at three units.

<span class="mw-page-title-main">Fukushima nuclear accident (Unit 2 Reactor)</span> One of the reactors involved in the Fukushima nuclear accident

The Fukushima Daiichi reactor, was 1 out of 4 reactors seriously affected during the Fukushima Daiichi nuclear disaster on 11 March 2011. Overall, the plant had 6 separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). At the time of the earthquake, Reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance.

<span class="mw-page-title-main">Fukushima nuclear accident (Unit 1 Reactor)</span> One of the reactors involved in the Fukushima nuclear accident

The Fukushima Daiichi reactor, was 1 out of 4 reactors seriously affected during the Fukushima Daiichi nuclear disaster on 11 March 2011. Overall, the plant had 6 separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). At the time of the earthquake, Reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance. Unit 1 was immediately shut down automatically after the earthquake, and emergency generators came online to control electronics and coolant systems. However, the tsunami following the earthquake quickly flooded the low-lying rooms in which the emergency generators were housed. The flooded generators failed, cutting power to the critical pumps that must continuously circulate coolant water through the reactor core. While the government tried pumping fresh water into the core, it was already too late due to overheat. In the hours and days that followed, Unit 1 experienced a full meltdown.

<span class="mw-page-title-main">Fukushima nuclear accident (Unit 3 Reactor)</span> One of the reactors involved in the Fukushima nuclear accident

The Fukushima Daiichi reactor, was 1 out of 4 reactors seriously affected during the Fukushima Daiichi nuclear disaster on 11 March 2011. Overall, the plant had 6 separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). In the aftermath, Unit 3 experienced hydrogen gas explosions and suffered a partial meltdown, along with the other two reactors in operation at the time the tsunami struck. Reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance.

<span class="mw-page-title-main">Fukushima nuclear accident casualties</span> Possible casualties and related deaths caused by the Fukushima nuclear disaster

The Fukushima Daiichi nuclear accident genshiryoku hatsudensho jiko) was a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. It was the largest nuclear disaster since the Chernobyl disaster of 1986, and the radiation released exceeded official safety guidelines. Despite this, there were no deaths caused by acute radiation syndrome. Given the uncertain health effects of low-dose radiation, cancer deaths cannot be ruled out. However, studies by the World Health Organization and Tokyo University have shown that no discernible increase in the rate of cancer deaths is expected. Predicted future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have ranged in the academic literature from none to hundreds.

<span class="mw-page-title-main">Investigations into the Fukushima nuclear accident</span>

Investigations into the Fukushima Daiichi Nuclear Disaster (or Accident) began on 11 March 2011 when a series of equipment failures, core melt and down, and releases of radioactive materials occurred at the Fukushima Daiichi Nuclear Power Station from the 2011 off the Pacific coast of Tohoku Earthquake and tsunami on the same day.

<span class="mw-page-title-main">Accident rating of the Fukushima nuclear accident</span> INES rating of the Fukushima nuclear disaster

The Fukushima Daiichi nuclear disaster genshiryoku hatsudensho jiko) was a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. It is the largest nuclear disaster since the Chernobyl disaster of 1986.

<span class="mw-page-title-main">Safecast</span>

Safecast is an international, volunteer-centered organization devoted to open citizen science for environmental monitoring. Safecast was established by Sean Bonner, Pieter Franken, and Joi Ito shortly after the Fukushima Daiichi nuclear disaster in Japan, following the Tōhoku earthquake on 11 March 2011 and manages a global open data network for ionizing radiation and air quality monitoring.

References

  1. ↑ Nuclear Safety Commission. Regulatory Guide: Regulatory Guide for Reviewing Radiation Monitoring in Accidents of Light Water Nuclear Power Reactor Facilities Archived 2011-07-20 at the Wayback Machine . September 2006.
  2. ↑ Nuclear Safety Commission. NSCRG: L-RE-I.02. Guide for Radiation Monitoring of Effluent Released from Light Water Nuclear Power Reactor Facilities Archived 2011-07-21 at the Wayback Machine . September 1978.
  3. ↑ Chino, M.; H. Ishikawa; H. Yamazawa (1993). "SPEEDI and WSPEEDI: Japanese Emergency Response Systems to Predict Radiological Impacts in Local and Workplace Areas due to a Nuclear Accident". Radiation Protection Dosimetry. 50 (2–4): 145–152. Archived from the original on 11 October 2013. Retrieved 11 April 2011.
  4. ↑ "Radiation doses spread unequally / Experts say govt should give more detail in designating evacuation zones". The Yomiuri Shinbun. 27 March 2011. Retrieved 11 April 2011.
  5. ↑ The Japan Times (17 January 2012) U.S. forces given SPEEDI data early
  6. ↑ Austin, Bill (28 March 2011). "IPhone Versus Soviet Subterfuge Make Fukushima No Chernobyl". Bloomberg Businessweek. Retrieved 11 April 2011.[ dead link ]
  7. ↑ "Citizen scientists help monitor radiation in Japan". BBC Programs. 8 April 2011. Retrieved 11 April 2011.
  8. ↑ Courtland, Rachel (25 March 2011). "Radiation Monitoring in Japan Goes DIY". IEEE Spectrum Tech Talk. Retrieved 11 April 2011.
  9. ↑ "Study: Modeling Fukushima NPP Radioactive Contamination Dispersion Utilizing Chino M et al source terms". Progressive mind. 27 October 2011. Archived from the original on 11 March 2012. Retrieved 20 March 2012.
  10. ↑ "Crowd-sourcing aids Japan crisis". BBC News. 21 March 2011. Retrieved 11 April 2011.
  11. ↑ Madrigal, Alexis (11 April 2011). "The Open-Source Project to Build a Citizen Radiation Detection Network in Japan". The Atlantic. Retrieved 12 April 2011.
  12. ↑ Alvarez, Marcelino (May 7, 2011). "RDTN.org: Radiation Detection Hardware Network in Japan". Kickstarter.
  13. ↑ Akiba (April 11, 2011). "Tokyo Hackerspace/RDTN Geiger Shield - Dev History".
  14. ↑ "Crisis Mapping: RDTN.org" . Retrieved 6 January 2014.
  15. ↑ "Interview, Marcelino Alvarez (Uncorked Studios, Portland, Oregon, USA)". BBC (6 min). 5 Apr 2011. Retrieved 6 January 2014.
  16. ↑ [Bonner], Sean (April 24, 2011). "RDTN is now Safecast" . Retrieved 6 January 2014.
  17. ↑ "beh che ne pensi [well what do you think] RDTN is now Safecast". Archived from the original on 7 January 2014. Retrieved 6 January 2014.
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