Cleat Hill Borehole Sealed with Cement Following Fatal Explosion

Safety officers report that a 100m (328ft) borehole, situated near the site of a deadly explosion and house fire, is undergoing a cement filling process to guarantee its “gas tight” seal. The incident, which occurred at Cleat Hill in Bedford on 19 October, resulted in the death of 85-year-old Paul Swales. Julia Harris, aged 84, succumbed to her injuries in hospital ten days subsequent to the blast. The Health and Safety Executive (HSE) stated that a 15m (49ft) plug had been inserted into the borehole, expressing confidence that “the cement is holding the gas back”. A British Geological Survey team, present at the location since 21 October, indicated ongoing gas monitoring in the vicinity and observed a reduction in gas levels since the commencement of the filling operation. Bedfordshire Fire and Rescue Service, maintaining a continuous 24-hour presence at the site, reported that it had “yet to determine the exact cause” of the explosion, with investigations still in progress. This explosion took place in the identical area where, on 2 July, contractors previously encountered a pocket of natural gas during the drilling of a borehole for a heat pump installation, leading to the evacuation of adjacent properties. A distinct, ongoing inquiry is currently examining the circumstances surrounding the gas leak that occurred in July. Following the 19 October incident, approximately 50 households were evacuated, and a 100m cordon around the affected zone remains active. Paul Bradley of the HSE informed a residents’ meeting that the period had been “an eventful few days”. He verified that both mud and cement had been introduced into the hole, reaching a depth of 102m (335ft). He affirmed, “A plug of 15m of oil and gas cement has been placed in there, that has been set and has cured.” He further stated, “The 15m plug in the bottom is actually gas tight, that it’s holding the gas where we want it to be.” Bradley outlined the intention to continue adding cement up to the surface for a complete seal, reiterating, “We are confident the cement is holding the gas back.” Michelle Bentham, representing the British Geological Survey, reported that her team had consistently monitored and measured gas levels in both the soil and atmosphere, noting that elevated gas concentrations had been detected at various locations and times. She confirmed the presence of high methane gas levels in the area, but observed that these levels were decreasing since the borehole filling commenced, which she described as a “good indication that is working”. John Finley, from the Ground Source Heat Pump Association (GSHPA), commented, “This is the only occurrence of shallow gas known in over 25 years of GSHP operations in the UK.” He characterized the situation as a “tragic event” that is being addressed with seriousness. Finley added, “Where necessary we will make changes, modify standards and procedures, already in use.”