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Demonstration of an Explosive Process Building Being Decontaminated by Burning
An eyewitness account by BAG - Thursday 10th November 2005
Three members of BAG were invited by BAE to observe the decontamination of a typical explosives process building at the ROF site. The object of this exercise, as stated in the letter of invitation, was to "inform stakeholders in the Bishopton ROF Regeneration Scheme about the recognised methodology for this process". Those present included members of the Community Liaison Group, Community Council, SEPA, Forestry Commission, Redrow, Bob Darracott (Director of Planning), Jim Dewar and other Renfrewshire Council representatives, Graham Vincent (BAE), Dr Alison McKay (BAE) and various others.
It was a cold, blustery and showery day, but we were treated to tea and biscuits on our arrival. Graham Vincent and Alison McKay gave a short presentation on the history and use of the site. They explained that it comprises 986 hectares, and was used for the production of military gun and rocket propellant for nearly a century. Ball powder was manufactured and phosphorous filling was carried out also. The Georgetown factory was used for the filling and assembly of large calibre ammunition during Word War I.
The former buildings which dealt with explosives are now contaminated, as it was inevitable that dust would find its way into the cracks and crevices of buildings. Two methods of decontamination were described - water/steam jetting, and controlled burning - the latter being most effective. These are "tried and tested" methods accepted by the HSE explosives inspectorate. Dangerous materials (e.g. asbestos) are removed before the building is burned, weather conditions are constantly monitored, and appropriate authorities (including local residents) are notified in advance. After the fire, they check that the heat has penetrated all areas of the building, and undertake the safe crushing of building materials. It was explained that BAE have a "proven track record" of decontaminating buildings e.g. Chorley (over 400), Waltham Abbey etc. There is a 150 metre safety zone and no-one is allowed within this area, other than the people doing the actual "burn".
After the presentation, we were minibused approximately half a mile to the centre of the site We were struck by the large numbers of brick buildings dotted all over the site. There are also many grass covered, reinforced concrete underground storage chambers (these will take some shifting!). Graham Vincent informed us that there are more than 1,000 contaminated buildings on the site. The building used for the presentation is a basic brick construction with a concrete roof. This is typical of the majority of buildings on the site, and the only means of creating a fire within such a building is to fill it with straw and timber as fuel.
Our observation party was located some 300/400 metres from the building to be used for the demonstration. Three straw channels were lit simultaneously to feed fire from outside to the inside of the building. We were warned that, in the event of a "problem", we would be asked to move quickly to hide behind an adjacent building. We observed the building burning for some 20-25 minutes and were advised that temperatures of 750 degrees, then 1000 degrees were achieved. At first, black smoke emitted (as we had been told to expect) for about 5 minutes and then more acceptable grey smoke continued. At one point, after approximately 15 minutes, slightly alarming-looking greenish smoke belched horizontally through windows, but this lasted for only a few minutes. Graham Vincent advised that "this would be investigated". The building had large aluminium cowlings and horizontal ventilation funnels on the roof. We remarked that fire did not pass through these units and were advised that they would "probably have to be dealt with separately".
We asked how they would deal with the buildings known to be contaminated and situated adjacent to Bishopton housing - would it be the same method as demonstrated today? The answer was that neither of the two methods described earlier (water/steam jetting or controlled burning) was suitable, and the rather vague suggestion was that there would probably be some type of "controlled demolition" and removal for burning to another part of the site. Graham Vincent acknowledged that they were not too sure about this, but they know that this is a "contentious" issue. They will deal with each building on an individual basis, and they have a record of every building on the site and what it was used for. We also asked about the danger from the smoke particles-the answer given was that the materials are broken down into their constituent parts by burning, and that there is no more danger than "smoke from a bonfire".
As far as the explosive ingredients are concerned, this is probably true. However, we know that many of the propellant mixes contained additional chemicals such as fluoride or lead. These could be carried off in the smoke and would still present a potential hazard. We felt that the above statement was simplistic, Later we also considered the fact that the fire has presumably to reach the specified temperatures in order to render the contaminants "safe".
As a whole, the demonstration - the potential risk of fluoride, lead or other contaminants blowing in the wind, and the general vagueness of how they propose to deal with the buildings situated close to the local community - did not reassure us.
We left the site feeling rather dejected about the process of site contamination in the hands of these "experts". Let's hope that they can provide better answers to our fears and concerns before they are allowed to start to treat the remaining 1000+ contaminated buildings.
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