Case Studies

Buncefield Supply Depot - Fire water following a major oil fire 2005

Following the Buncefield Depot fire in December 2005, approximately 23 million litres of contaminated fire water was successfully contained following the fire. However, the post-fire issue of how to deal with this contaminated run-off has caused as many problems as extinguishing the fire itself.

It should be recognised, and those involved praised, that this volume of contaminated fire-water run-off did not reach sensitive water systems, in stark contrast to previous cases. Containment in this instance has been the first and most important priority, given that the degradation products from the foams used during this fire will contain both PFOS and H-PFOS.

The problem in this case is not just the volume of water but the level and types of contamination contained in the water. It is not credible to simply hope that a water company can mix these waters with those that are normally treated, such as sewage.

 

The contaminants present in this fire-water are likely to destroy the vital biosystems used to biodegrade sewage during treatment. Furthermore, the fluorinated materials found in the foams used during the fire will not be removed by water company processes and will remain and build up in the retained sludge, which is then normally sent to agricultural land.

The only safe option for dealing with fire water is to systematically employ processes that remove the individual contaminants such as hydrocarbons, oils, grease, polyaromatic hydrocarbons, proteins and so on. The fluorinated molecule can then be removed by filtering the water through a specially designed carbon matrix.

Simply diluting fire water does not remove contamination. The contamination remains, regardless of the amount the liquid is diluted.

As a case study, the Buncefield incident has not yet reached a conclusion. However, the clean up operation will have implications for the fire engineering industry long into the future.