The coverage of the 76 hectare fjord bottom takes place by using a well-proven method. The goal is to limit the risk of future spread of environmental toxins after more than 90 years of extensive industrial activity on Herøya. The pollution consists of, among other things, mercury, dioxins and furans, primarily from the chlorine plant and the magnesium plant, which were closed in 1987 and 2002, respectively.
Hydro for many years has worked on examining the situation and planning measures. The goal is a good environmental condition in the Gunneklevfjord, and the company follows up on the requirements of the Norwegian Environment Agency as quickly as possible.
At present, planning and piloting of measures are under way, including testing of various methods of coverage in smaller parts of the fjord. The results of these tests will form the basis for determining the equipment as well as the suitability and thickness of the coverings. The actual covering of the fjord floor should be completed by the end of 2021. If there is a fill with rock masses from the E18 development, the covering will be carried out after the fill and could be completed in 2023/2024.
In addition to the required cover, a former marina in Gunneklevfjord had to be relocated to Frierfjorden. Hydro has provided grounds for this, and the new marina was established in 2019 in collaboration with the Herøya Motor Boat Association.