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Tuesday, February 10, 2009

SEPA REPLY ON DALGETY BAY

This is a reply I got from SEPA to my email given on last Monday's blog together with my response, new questions & repetition of unanswered ones
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Thank you for your enquiry about the radium contamination that has been found at Dalgety Bay.

While I recognise that radium-226 is a naturally occurring radionuclide, being part of the uranium-238 decay series, the concentration of radium found at Dalgety Bay is many orders of magnitude higher than is found in nature, and as such is a consequence of a man-made activity.

For example one of the particles identifed had an activity of 147,000 Bq of Radium-226 with a weight of just over 1 gram. This compares with activity levels of a few hundred Bq per Kg for the most active granites. There is therefore roughly a factor of 1 million between natural concentrations and the activity found in the items reciovered at Dalgety Bay in this case. Other particles found also present large factors between the radium concentration found and those that occur naturally. The information on particle activity is contained within the report found on SEPA's web site. On this basis the presence of the radium found at Dalgety Bay cannot be attributed to natural sources. This is the evidence to which I referred during the interview on Radio Scotland last week.

The lack of high concentrations of the higher members of the uranium-238 series consistent with the radium found also points to the radium being of man made origin.

Over the years, many items have been recovered from the Dalgety Beach including luminised dials, a vial of active material, and there is therefore strong circumstantial evidence for there being luminised paint items on the beach. Previously much of the activity recovered was associated with clinker which demonstrated that the material had been burned in the past. The burning of luminised items was once a common disposal practice and I have experience of that type of contamination at another site which has now been remediated. We are also aware that the small particles or flakes that have been found on the beach are similar to those described to us by someone who worked on the airfield after the second world war when luminised intrumnetrs continude to be maintained and repaired.

The sentence to which you refer in your email about our belief is not about whether or not the contamination is due to luminised paint, but relates to the degree of proof that it is due to activities of the MoD.

I trust that this addresses your questions.

Byron Tilly
Radioactive Substances Manager
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Thank you for your letter Mr Tilly which, on first reading sounds impressive. Less so on seeing what it actually says & equally what it doesn't.

The claim that radium must be artificial because it is "orders of magnitude" (i.e. 10s of times) greater than background is dubious. When Henri & Marie Curie processed many tons of pitchblende to find enough radium to cover the bottom of a cup they were starting with something orders of magnitude more concentrated than background - indeed that is implicit in the ore of any rare material. Had the measuring instruments existed at the time the Curies would certainly have found particles within the pitchblende which was in turn orders of magnitude more radioactive than that - indeed that is ultimately what they did. I would be interested to know whether you have investigated Kerala, Yellowstone Park or Guarapart bech in Brazil, all with natural radiation levels much higher than official safe limits without even statistiical evidence of any harm, to determine that similar levels do not occur naturally there?

Your claim to have found actual dials is more spectacular. On the other hand it raises the question - if you have found such radioactive dials, in the plural, lying about on the beach why does your report limit itself to claiming "A total of 37 items were retrieved from 29 locations in the survey area. The depth at which these items were retrieved ranged from surface to 270 mm below ground level. The size of the recovered items varied from 1 mm to 120 mm, whilst the weight range was less than 1 g to 380 g." This is like saying you found evidence of mice behind the skirting board but never thought to mention the herd of elephants. Even more surprising is the claim to have found a vial of (radio)active material. If this is a vial of radium paint, as you imply, which had lain unbroken on the shore for over 50 years it would be a most remarkable specimen - particularly since the painting of the dial took place prior to the manufacture of the aircraft, rather than when it was being flown so there is no conceivable reason why it would have been on the airfield in the first place.

As to what you don't say. Firstly you don't say that the claim, made nationally & still being maintained by SEPA, to have analysed actual radioactive particles & proven them to have been paint, is actually in any way true. Even if some non-radioactive paint particles have been found this does not prove they came from the airfield, let alone from the aircraft in question, let alone from the cabin of the aircraft, let alone from numbers painted on the interior of a few dials. Is the claim to have had these microscopic particles tested & proven to be paint true or false? If it is false when did SEPA ask the BBC to report this & fire the man who said it?

Secondly SEPA have refused to answer my question about background radiation in the area & adjoining beaches. Is Dalgety Bay's significantly above that found elsewhere? Does it even approach the levels found elsewhere, including in popular tourist attractions like Yellowstone mentioned above?

If the answer to any of these questions is No then SEPA have clearly lied & are maintaining the lie, in a manner bound to inspire false fears in the public & to have a positive effect on your own budget. As Mencken said "The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary." What actual evidence have you that this particular hobgoblin is not imaginary.

On a slightly different matter was the statement by SEPA representative Colin Bayes, reported by you that the MOD have recognised that the radiation comes from them & it is their responsibility to clear it up actually true?

Comments:
On the comment trail of your 7 December post you wrote My understanding is that radium occurs from the breakdown of uranium but since its half life is 1,600 years & uranium's is millions there is always bound to be relatively little of it. The Curies had to refine out many many tons of pitchblende to find a tiny amount of natural radium - but they did find it. If a high proportion of the radioactivity here really were proven to come from radium that would be strong evidence...

This has been proven to the extent required by sane people. The evidence is in the 2006 SEPA report as detailed in the comment trail to your 7 February post.

In addition, you have again not read what you cite. At page 13 of the 2006 Report, at section 3.2.1. page 13, SEPA note that they have screened their samples for background radiaition thus "assuming a background radiation level of 150 counts per second (cps), and a threshold for positive identification of a radioactive item producing a count rate of 75 cps above background level....

You assert SEPA are lying with no proof. You assert the Sunday Herald is lying with no proof.

Your own questions are answered so you ask new ones designed to be unaswerable.

Whatever else is proved here, it is abundantly clear you are no scholar.
 
Or if one assumed a background radiation level of 225 that would mean zero artificial radioactivity. The local background radiation in adjoining beaches is one of the things I have been trying to get SEPA to produce figures for - & which they have repeatedly refused to do. Variations of far more than 50% are common.
 
1. Radiation meters can be purchased here in the US for $300-500 if you really want to know the radiation levels on that beach. Reply to this comment and I will find the page I saw a few days ago.

2. Here is a good satire of the British H&S authorities and political correctness.
 
Have they actually refused you this information or simply not answered? There is a wee bit of a difference. There would seem to be no point in hiding something in the public domain and the Dalgetty Bay Monitoring Report of March 2005 gives the background count as 50-55 cps typically at page 2. See:

http://www.sepa.org.uk/scotlands_environment/data_and_reports/radioactive_substances/dalgety_bay_reports.aspx

There is also a useful map at page 17 of the May 2006 Report at the same URL.
 
I suspect any commercial geiger counter would be too insensitive to detect any alleged excess radiation there.

Your link to how Trafalgar would have gone under PC rules is all to true.
 
These aren't commercial Geiger counters, they are former government radiation meters. During the early Cold War the US was devising plans to protect some of the civilian population and was training the remainder to protect themselves from nuclear blast and fallout. As part of this effort the federal government equipped local fire and police departments with radiation meters, which makes sense in a world where radiation sources are common in industry. When Bill Clinton first came into power he had a Democratic congress and together they dismantled America's civil defense system, part of which included calling in all radiation meters that had been given to states. These meters and other fed surplus are now available for sale here and here are the low range meters you are looking for. Some of the low range meters at the bottom of the page have readouts in counts per minute. The rest of the meters report radiation levels in rads or millirads. There is a formula on the site for converting between cpm and rads somwhere...


They also have standard civil defense meters (like mine) that are accurate up to 400 rads here. Of course, if you are standing on a beach in Scotland and begin picking up that much radiation then The End is Near.
 
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