The owners of a further 50 properties in the area are now being contacted and more tests will be carried out in an effort to find out where the very low levels of perfluorooctane sulphonate, or PFOS, are coming from and what, if anything, should be done.
The traces discovered this month are well below the safe limit prescribed by the World Health Organisation.
Previous PFOS contamination in St Ouen’s Bay is believed to have come from a former Airport firefighting training area widely used in the 1990s.
Dozens of homeowners were compensated and connected to mains drains at the cost of the States.
And in 2005 the States accepted a £2.6 million payout from American multi-national and PFOS manufacturer 3M, part of which was used to carry out remedial works to the land affected at the Airport.
