Gentlemen All,
I thank you for your explanations as to why mass balances were needed, and used. A little bit more aviationeering understood! You will remember, though, in my original post that I said I was very interested in what materials might have been (or are!) used. I didn’t want to pre-empt any reply but the several separate mentions of Depleted Uranium has, I think, solved the problem.
Shortly after Chernobyl the UK Govt decided to set up a country-wide network of radiation monitoring stations. Quite a lot of these were on airfields (civil and military). One was installed in the middle of a fairly busy airport in the Midlands. After about a year’s worth of data had been recorded it was noticed that there were some persistent ‘spikes’ in the radiation levels above the normal background (not high enough to trigger the alarm threshold!). I was asked to investigate this. The data were analysed. All sorts of tricks were used. Did the spikes co-incide with the operation of any electrical equipment? (We’d had a radio controlled camera filming a Harrier test which kept firing off “random” frames. This was eventually traced to opening/closing the fridge door in the transport cafe in who’s car park we were working!!! – so you can’t be too careful!). No correlation. Did the spikes occur when it rained/thundered/hailed/ATC radio, etc, etc,? – no correlation. Finally, in despair, I plotted the spikes against wind direction – BINGO! They all came from 3 distinct directions – and were persistent. Half a mile to the NW of this airfield is a manufacturing facility. There were spikes when the wind blew from this direction. One mile to the SW is a similar facility – ditto. But, the third ‘spike’ direction was from the SE. No immediately observable industrial process there – except the aircraft handling apron!!! I think, Gentlemen, you may have solved a conundrum that has been bugging me for years. Thank you.
I have, by the way, no knowledge if the radiation monitor is still there, or which Govt Dept is now responsible for correlating the data. The Met Office had the monitors on a number of its sites, but simply passed the data on. The Home Office (Civil Defence lot) did a lot of work, but when they were done away with I have no idea where the figures went .
My thanks again
Resmoroh