The discovery of potentially hazardous firefighting chemicals at a former RAF base in Oxfordshire has sparked renewed calls for urgent action. Newly released Ministry of Defence papers reveal that these substances, known as per- and polyfluoroalkyl substances (PFAS), were deliberately washed down drains at RAF Upper Heyford between 1997 and the site's closure by the US Air Force.
The documents, obtained by the BBC, detail land and groundwater assessments conducted during the MoD's preparations to sell the site. A fire training area is highlighted as a specific location where firefighters practised extinguishing aircraft fires over a 'pond' of fuel, with potential contaminants including petrol, oil, lubricants, solvents, and 'firefighting chemicals', which were allegedly drained into storm water drainage.
PFAS, often referred to as 'forever chemicals' due to their persistence in the environment, have been extensively used in firefighting foams. The Environment Agency (EA) has identified military sites and airports as hotspots for these substances. Dr David Megson, an environmental forensics expert specialising in PFAS, commented on this case: 'This appears to be another concerning instance where these chemicals were widely used and have escaped into the environment, with long-term harm only now beginning to be understood.'
Recent tests by residents and the Environment Agency have revealed elevated levels of PFOS – a specific type of PFAS used in firefighting foams, classified as carcinogenic to humans – in six local streams. One test recorded PFOS concentrations at 27,823 nanograms per litre (ng/l), significantly exceeding the Environmental Quality Standard (EQS) for PFOS in inland surface water, set at 0.65 ng/l.
A 1997 environmental risk assessment within the documents warned of potential human health risks if 'impaction of the groundmass and groundwater have occurred', with possible effects including dermatological contact, inhalation, and ingestion of both soils and groundwater. The report also noted that grazing animals on-site or in surrounding farmland could be affected by ingesting impacted soils and/or spring waters.
Dorchester Living, the current owners seeking permission to build 9,000 homes on the site, confirmed no previous PFAS testing had been conducted. Local MP Calum Miller, who received the documents, stressed that the new information makes urgent testing 'all the more necessary', with a meeting scheduled to discuss the findings with relevant ministers.