Villagers in Brightwell Baldwin in Oxfordshire celebrated the Queen's Diamond Jubilee in style, lighting a hilltop bonfire as one of the nationwide chain of 4000 beacons being lit simultaneously. But the organiser had a background in the gas industry, so he was nervous about lighting a fire above an old landfill site. Leigh Greenham, who has been involved in the gas detection business for many years and runs CoGDEM, the trade association that Geotech is a member of, was concerned that low level leaks of methane from underground could be enough to fuel a potential explosion. Drawing on industry contacts, he asked Geotech to have a quick scan round the site with their new laser-based TDL-500 methane leak detector.
Graham Sanders from Geotech visited the site a month before the Jubilee. 'Although we were able to detect slight emissions from the test holes dug on the site, nothing greater than 30ppm was seen and we were happy to go ahead with the event,' said Leigh Greenham. The portable TDL-500 uses laser technology to detect methane down to 1ppm. 'It was a good test for the analyser on an old landfill site,' commented Graham, 'and I was pleased to be able to put everybody's mind at rest. Although this was an unusual request, the actual application is fairly typical for the TDL-500, which is great for spotting and pinpointing leaks around landfill sites, contaminated land, petrochemical or sewage processing plants.'
'Our village beacon event was a fantastic success, and there were no flames in places where flames shouldn't be,' said Leigh. 'We had around 100 happy villagers at our party, and once the beacon was well alight, we toasted the Queen, not on the bonfire, but with champagne! The farmer who let us use the site was very happy with the way things went and that we had checked the safety of the site beforehand. Now that he knows the site is emission-free, he joked with villagers at the party that he might build a housing estate there, so that everyone really remembers the Jubilee!'