ARPANSA Responds to a Citizen’s detection of a radiation “spike” in Queensland, January 2012.

Please see the preceding post before reading this one. Please also read the following news report:

The following is my opinion on the Radiation Spike reported, and my opinion of the ARPANSA response to the public via the Sunshine Coast Daily of 14 January 2012. I am either right or wrong at each point. I have questions for ARPANSA.

ARPANSA’s detailed paper regarding radionuclide emissions from the Lucas Heights reactor was written as a response to the Comprehensive Test Ban Treaty Organisation (CTBTO) detection of a radition plume from it’s Melbourne site. The paper, “Evaluation of radioxenon releases in Australia using atmospheric dispersion modelling tools” was the result of an internatioal collaboration involving the University of Vienna, ARPANSA staff, including Marcus Grzechnik and ANSTO staff. It is important to note that figure 10 (upper thumbnail) shows wind direction variation with altitude and time dispering the emitted plume in 3 different directions from the one emission event. Note that while one part of the plume went southerly, one went on a westerly then southerly direction and another part of the plume went easterly, and, upon reaching the coast, proceeded in a north earterly direction.

The paper was published in a scientific journal in May 2010. One would assume that Marcus Grzechnik would have some recollection of contributing to the paper just over two years later. The Sunshine Coast Daily of 14 January 2012 describes Marcus Grzechnik as “Australian Radiation Protection and Nuclear Safety Agency senior environmental scientist”. Marcus of course is one of the authors of the paper published in 2010.

ARPANSA has a duty to recall, in general at least, that the major radionuclide plume emitter on the eastern seaboard of Australia emitted plumes which which covered most of New South Wales, a large protion of Victoria, some of South Australia and with Queensland impacted by these airborne plumes both within itn its land area and its coastal and offshore waters. These are the facts as reported and published by ANSTO and ARPANSA , together with their collaborator, Vienna University in May 2010. The paper is available at Science Direct, as previously cited.

The emitter involved in the 2008 and 2009 plumes which were subject to the 2010 paper is the ANSTO Lucas Heights reactor, and the ANSTO website gives the relevant start and refuel dates for that reactor. If these cycles and refuelings are of environmental interest, then ARPANSA and it’s environmental officers would know what happened at the reactor immediately prior to 8 January 2012, the date Mr Daley first recorded unsual radiation readings. The fact is that immediately prior to 8 Jan 2012 the ANSTO reactor was being refuelled. When a reactor is refuelled, its emissions increase (Fairlie, 2009).

At the moment, scientific papers are being written discussing the short comings of assessing risk from nuclear reactors where emissions increase during refueling. Papers cite Fairlie, 2009 as one source. The matter is one of debate within the qualified scientific community.

Many people, including people all over the world via the international media, know of the radiation spike which was detected by Mr Daley of Caloundra. It was reported by the Sunshine Coast Daily on 14 January 2012. International media relate that “Australian authorities” confirmed the reading and that it came from Fukushima, Japan.

Reporter Kate Clifford interviewed ARPANSA’s senior environmental scientist about the radiation spike. The following is the complete quote of all that is reported to have been said and communicated to the reporter by the ARPANSA representative:

“Australian Radiation Protection and Nuclear Safety Agency senior environmental scientist Marcus Grezechnik said the reading was unusual but not concerning for the Coast.

“It is very unlikely to be caused from Fukushima, but more likely to be caused by a weather change or dust,” Dr Grezechnik said.

“It is not seen as a big increase although it is higher than average. To put everyone’s mind at ease, even if you were receiving that dose every hour for a full year you would have less dose than one CAT Scan.”

He said radiation from the Fukushima nuclear disaster had only been recorded in Australia once since the incident occurred in March 11.

“All reactors at the Fukushima Dai-ichi site were now in cold shutdown, significantly reducing the likelihood of uncontrolled releases to the environment and associated health impacts,” he said.

The ARPANSA senior environmental scientist had a duty to disclose to the Australian people both the previous plume events from ANSTO’S reactor and the current disposition of reactor emissions from Lucas Heights.

The dip in Mr Daley’s radiation chart reaches nearly to zero. This is probably an artefact of the meter. One expanation for this is the condition known as “False Zero”, a well event in an “overloaded” GM meter. In this condition a GM meter is in a state whereby it ceases to accurately detect even usual background radiation. In my opinion, the spike which Mr Daley reported occurs shortly after this zero reading on the chart.

ARPANSA’S senior environmental scientist claims to know the maximum reading of the plume which was read by Mr Daley’s meter.

The Geiger Muller based instrument used by Mr Daley is, like all such devices, vulnerable to “false zero ” readings when exposed to radiation fields above its maximum capacity. As a result, the the maxiumum reading of the chart produced by the meter and computer interface actually occurred at the dip. At that point the device was “saturated”, incapable of giving a reading, failing to report even the stable background, and from which it would take a very brief period to recover when the field dropped sufficiently.

The spike, described as being 8x background by Mr Daley, is not contradicted by ARPANSA’S senior environmental scientist, who confirms that the readings are, in the view of ARPANSA, perfectly safe.

GM radiac meters can give false zero readings when overloaded.

It is my opinion that the strength of the field detected by Mr Daley’s meter rendered the device inaccurate for a brief period. The maximum reading, being outside of the meter’s range, and not being read anyway, is unkown. Whatever it was, it occurred at the dip point, the zero read point, in the graph. The graph shows the GM meter recovering prior to the “peak” read. This recorded peak read occurred actually, in my view after the radiation field reduced to the point where the meter could recover and read the field.

One cannot determine what the maximum reading actually was. For it was above the maximum capacity of the meter to detect and display. I submit that the meter became, for a brief period “saturated”. I shall list common sources which confirm this characteristic of Geiger based radiation detectors shortly.

So, where did ARPANSA get it’s data from if not Mr. Daley’s meter? The dip in the graph, which is a failure to detect background and a sign of a meter artefact, is a warning of meter overload and false zero. In any event, the failure to read background is cause for questioning the reading at that point.

Geiger tube “false zeros” are well known. ARPANSA and ANSTO own the appropriate meters. Were they used in relation to the plume over Australian water and land on that day? If not, we will never know the true value of the radioloigcal event reported by Mr Daley. If they were used, we need to know the readings. We don’t need assurances of safety from ARPANSA when we don’t know what the maximum reading was.

For a non technical explanation of “false zero readings” in Geiger Muller tube based radiation detectors see: Word search for “false zero” in this web page.

For a common, technical explanation see which states this: “If the applied voltage is too high, a continuous glow discharge is formed and the tube cannot detect radiation.”

This is my perception and understanding of the events revealed by both the written record of reactor plumes, published 2010.

ANSTO Reactor Power Cylces

Quote: “Typical operating cycles

OPAL typically operates in cycles of 30-35 days, followed by a short refuelling outage to remove two or three spent fuel elements and replace them with new fuel elements.

During these types of outages, ANSTO’s Reactor Operations team complete any required inspections and perform preventative and corrective maintenance on the reactor. These refuelling outages currently last around four to six days, although the intention is to reduce this in future.

The Reactor Operations team aims to operate OPAL for 300 days each calendar year.

Reactor schedule – 2011/2012*
Reactor at power*
32 14.05.2011 13.06.2011
33 1.07.2011 30.07.2011
34 5.08.2011 9.09.2011
35 20.09.2011 17.10.2011
36 23.10.2011 27.11.2011
37 4.12.2011 2.01.2012
38 8.01.2012 5.02.2012
39 12.02.2012 18.03.2012
40 2.04.2012 29.04.2012
41 6.05.2012 11.06.2012
42 17.06.2012 16.07.2012

*This schedule is subject to revision based on the need to change the heavy water inventory. This schedule is based on a fixed fuel management system.

Page last updated 12.07.11. Revision no: 16. ” end quote.

It is clear that if running on schedule, the Lucas Heights reactor would have been refuelled prior to its restart on 8 Jan 2012.

Given the ARPANSA/ANSTO previously published paper which disclosed Lucas Heights reactor gas plumes travelled off shore adjacent to the NSW and Queensland coasts, and that the plumes also travelled over land into Queensland, I consider Lucas Heights emissions the very probably cause of the radiation reading event reported on 14 January 2012.

The ANSTO reactor was restarted on 8 Jan 2012 and prior to this was being refuelled. The emissions from the ANSTO site were possibly emitted on 7 Jan 2012 or earlier.

I find the lack of disclosure by ARPANSA a reason for concern. While the organisation can expend fund assisting in the preparation of the 2010 Reactor plume paper regarding 2008 and 2009 emissions, it fails to fully disclose in this case involving a report of detection by a private citizen. ARPANSA’S degree of openness should remain constant, whether the cause of the disclosure is detection by an international monitoring organisation, as the early paper was, or whether it was detection by a private citizen. In any case, ARPANSA should be disclosing without prompting. Whatever the source of the emissions actually were.

The fact is the ANSTO reactor restarted on Jan 8 2012, prior to that it was being refuelled. Prior to 8 Jan 2012 the reactor was vulnerable to an emissions spike. This spike may have been a cause of the event recorded by Mr Daley’s meter.

ARPANSA has not yet disclosed the source/s and has not disclosed its measurement data of the event.

It is up to ARPANSA to disclose. Radiation safety monitoring in Australia must be transparent. It seems not to be.
From Tinker, Orr, Grzechnik, Hoffmann, Saey, Solomona, 2010.

Top Image shows Effect of wind direction variation with altitude. Surface wind direction only is insufficient to properly describe plume disposition. A cloud may descend from altitude after travelling from the south when surface winds are travelling from the north.

7 Responses to “ARPANSA Responds to a Citizen’s detection of a radiation “spike” in Queensland, January 2012.”

  1. Bammster Says:

    Firstly, It takes a lot of radiation to saturate that model Gammascout LND tube to give a dip like that. Not going to happen.

    Secondly, the wind directions at the time were from the Coral Sea, not from the land, and certainly not from anywhere near Lucas Heights.
    The fact that two jet stream conduits were active over the Tasman Sea is another issue.
    Radioactive materials were detected in the rain in New Zealand. The wind directions at the time varied between NW, NNW for a greater part of 48 hours.

    If Lucas Heights is releasing this much radioactive material into the atmosphere, as to be detected in New Zealand (by several sources), then there are some very serious questions to be answered.
    However, ARPANSA has been posed with nuclear safety questions before (especially the ANU cases) and has never given satisfactory answers. Actually, ARPANSA are a joke.

    Simply put, Lucas Heights isn’t releasing that much material (the locals might want to hold their breath though) – it is Fukushima, and there are very serious questions regarding radioactive fish, and radioactive Japanese products entering the NZ market for consumption.

    What Australia chooses to do about it is another matter. However Fukushima is releasing more than the Japanese government is saying, and there are going to be large scale health implications.

    • nuclearhistory Says:

      So what is your reason for the disappearance of background on Mr Daley’s graph prior to the spike?

      Regardless of that, its up to everyone to think for themselves. Given the lack of official information, that’s the best
      anyone can do. I’ve given my view, you’ve given yours. Governments have the capacity to monitor radiological events which are occuring. I would suggest to eveyone that looking at the ANSTO OPAL reactor website power cycles schedule may help at least define the extent of contribution from that source. Emissions increase when fuel rods are changed. Watch what happens, if anything from 6 Feb 2012 to 11 Feb 2012.

  2. Brief large spike in local background radiation. What caused it? :: Sunshine Coast Computer Club Says:

    […]… […]

  3. kiwi Says:

    Bammster, can you advise me about the source of NZ measurements? We are trying to collect data on for NZ radiation monitoring as there is no official data available. Please contact us on the website or on the emai address you can find there.

  4. Lucas Heights Reactor shuts down on 5 Feb for refuel between 6 Feb to 11 Feb 2012. Expect Emissions Peak « Paul Langley's Nuclear History Blog Says:

    […] <a href="…“> […]

  5. A most important paper regarding the extent of Fukushima Emissions . Stohl et. al. « Paul Langley's Nuclear History Blog Says:

    […] In January this year a member of the Queensland Sunshine Coast Computer Club reported a large detection of a large radioactive cloud. See this post:… […]

  6. Karl Morgan Describes a radiological explosion at Y-12 « Paul Langley's Nuclear History Blog Says:

    […] Footnote 9 Karl Morgan’s footnote to the above meter “saturation” experience: “As the Geiger counter was brought closer and closer to a source of ionizing radiation, clicks were produced faster and faster until the counter could not recover during counts. (a low resolving time) . Then the counts stopped and the pointer on the its meter dropped to zero. Any competent health physics surveyor would realize this was an acutely dangerous situation.” Karl Z. Morgan, Ken M. Peterson, “The Angry Genie”, University of Oklahoma Press, 1999, ISBN 0-8061-322-5, pp 59, 60. Further explanations of Geiger tube false zero readings include:… […]

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