The treatment facility for the environmental toxin PFOS opened in October and the initial analysis results from the facility in the fire drill area are very positive.
“The treatment plant on the west side of the airport opened this autumn, and we are optimistic in terms of the continued process,” says Grethe Østby Stave, department head for water and drainage management at Oslo Airport.
PFOS has been used in industrial and consumer products since the 1950s, mainly because of its excellent surface properties. This has made it an excellent choice for fire foam. It has also been used in ski wax, Teflon coating, oils, and for waterproofing textiles. PFOS is an environmental toxin that is not biodegradable, but remains in the environment for a very long time. Oslo Airport discontinued the use of fire foam containing PFOS in 2001, six years prior to the introduction of restrictions on fire foams containing PFOS in 2007.
“By establishing this facility, we believe we have control of the spread of PFOS from the fire drill area, and we have thus achieved a very important milestone,” says Østby Stave .
Discharges are under control – humans not at risk
In November 2013, Oslo Airport was ordered by the Norwegian Environment Agency to clean up the PFOS contamination at the fire drill area. This work was already well under way, as the process for a plan to clean this up commenced in 2011. Efficient clean-up of PFOS has been, and remains, pioneering work that takes time. Although several methods have shown good results in the lab and in small-scale outdoor trials, there are few instances of lengthy experience with proven measures at actual sites.
“In addition to cleaning the groundwater, we have also decided to clean waste water from the drill areas. A separate treatment system has been installed, comprising three containers with cleaning filters, and we are confident this prevents any PFOS-contaminated waste water from spreading to Ullensaker’s municipal waste water treatment plant,” says Østby Stave. OSL and Avinor are in the forefront in terms of handling PFOS pollution. One important aspect of this work is to document that the discharges do not pose a risk to humans.
Norwegian Environment Agency satisfied
The removal of PFOS from the fire drill area is scheduled to take place in two stages. The first stage was the procurements for processing groundwater, which were carried out during the 2014/2015 winter season. A pilot for treating groundwater commenced in May, and the main facility was in full operation on 9 October,
The next phase will consist of determining whether any other measures are needed to handle PFOS-contaminated soil. The planning and testing of this is now under way. The Norwegian Environment Agency inspected the site on 26 October, and they were satisfied with the progress that had been made.
“The fire drill area at Oslo Airport (OSL) is contaminated with perfluorooctane sulfonate (PFOS) from past use of the substance in fire foam, both in the soil and groundwater. The contamination has also spread with the groundwater outside the area and to streams. It has been important for the Norwegian Environment Agency that OSL has taken responsibility to stop the spread of contamination, and to clean up contaminated soil. The Agency is pleased that OSL, after a trial period, has started treating the groundwater, thus stopping the spread of contamination from the area,” says senior engineer Olaug Bjertnæs at the Norwegian Environment Agency.