Kartlegging av hvitt fosfor forurensning i Hjerkinn skytefelt

On assignment from Forsvarsbygg, FFI has assessed if there are traces of white phosphorus left from activities with use of white phosphorus smoke rounds at Hjerkinn firing range. White phosphorus is a highly toxic material that is noxious to all living organisms. In contact with air white phosphorus immediately reacts to non-toxic compounds, while in aquatic environments it can stay unreacted for several years. Water and soil samples have been collected from four different areas at Hjerkinn, both detonation ranges and demolishing ranges. To estimate the mass of white phosphorus in the samples, the samples were extracted with carbondisulfide and analysed on a gas chromatograph. Two of the water samples contained a small amount of white phosphorus. It is probably debris of white phosphorus deposited in Grisungbekken that contributes to the amount of white phosphorus detected in Grisungbekken. The debris is probably inaccessible for birds and mammals, so presumably it has no substantial harmful effects on living animals. But it is still very important to avoid detonation of white phosphorus smoke rounds in aquatic environments, in areas covered with snow and close to rivers and ponds.