DEFRA is not aware of any assessments that were carried out on the drainage system at the Pirbright facility prior to the investigation by the Health and Safety Executive (HSE) into potential biosecurity breaches at the Pirbright site. Until then, there was no indication that there was a risk of effluent escaping from the drainage system, although it was recognised that the system was old and some concerns were brought to DEFRA’s attention over the possibility of water leaking into the drains via the manhole covers.
On 17 August 2007, the HSE informed DEFRA Ministers that leaks could have occurred from the system and DEFRA immediately contacted the Institute for Animal Health (IAH). That afternoon, IAH put into effect a plan controlling access and strengthening biosecurity measures around the movement of people and vehicles. Work also began immediately on restoring the integrity of the drains and manholes concerned. Further inspections of the site have shown that the work had been completed quickly and to a high standard.
The report from the HSE investigation contains a detailed inspection of the drainage system, and is available from the DEFRA website and the Libraries of the House.