Sodium and calcium sulphate release into a marine recipient. A theoretical assessment of fate and effects.

Abstract

Weyland AS plans to establish a biofuels factory in Sørsalten, North Norway. The product will be bio-ethanol from wood-based material/cellulose. The factory is planned to be located at the head of Foldfjorden. Biofuel production would lead to discharge of sulphate, either as solid, inert calcium sulphate (“gypsum”), or as liquid sodium sulphate. Both substances are common in seawater, and as such they do not constitute anything new or harmful. The report evaluates the likely dispersion or disposal of the future discharge. The liquid is heavy and will tend to flow in a layer about 12 m above the sea bottom, dispersed by the ambient currents. The solid waste will remain in place on the seabed at the disposal site. Both types of discharge will impact to some extent the water chemistry and local biota near/at the discharge point, inside the mixing zone. Assuming that the waste holds no significant amounts of toxic substances, the environmental impacts are projected to be small.