In May and July 1982, two series of dispersant research oil spills were carried out off the Norwegian coast. The May series comprised three discharges of 2,000 liters of Statfjord topped crude oil (initial boiling point 150 °C). Two of the slicks were treated with dispersants (A and B) from a boat while the third untreated slick served as control. The July series comprised four discharges of 2,000 liters of Statfjord crude oil, with the application of three dispersants (A, B, and C), and one untreated slick as control. Water samples were collected from under the slicks and analyzed for total petroleum using a gas chromatographic technique.
Chemical analyses showed six percent dispersion of the oil for dispersant A, and 17 percent for dispersant ? in the May series. Effectiveness of dispersants in the July series was found to be 19 percent for dispersant A and 22 percent and two percent for dispersants ? and C, respectively. Gas chromatographic analyses showed in several cases the presence of dispersants (up to two ppm) in water samples without the presence of petroleum at all. The highest oil contents found in water samples were 10 ppm at a one meter depth. The variations in the effectiveness of the three dispersants tested in the field were later confirmed in laboratory tests.