Transport av eksplosiver : utlekking av eksplosiver under episode

Explosive contamination from ammunition consists of particles where the sizes of the particles are determined by the order of detonation. The particles are spread out on the surface of the ground and they are not very mobile. If the detonation takes place on snow the explosive particles can be transported with the snow during the melting season to creeks and rivers downstream the target area. An experiment has been carried out in Setermoen shooting range in order to investigate whether explosive particles can be transported with the melting snow to creeks downstream the impact area. Different collection units have been placed in a creek to collect explosive particles in the creek. Three types of plankton nets with different mesh sizes, one sand filter, two metal sieves and an automatic water sampler which was set to sample once a day have been used. Snow samples were collected at several locations in the impact area in order to measure the amount of explosives that have been deposited in the snow. Some explosive particles have been placed in the creek to get information about to what extent particles will dissolve in the running water. The results show that explosives residues were detected in only a few of the samples. One or several of the explosives TNT, HMX and RDX and the decomposition products TNB, DNB, 2- ADNT and 4-ADNT were measured in low concentrations in a couple of samples from the automatic water sampler, in two of the plankton nets and in the sand filter. Low concentrations of TNT and RDX were also found in two of the snow samples which were taken from a target point in the impact area. This area was, however, not localized in the drainage basin to the sampled creek. The TNT particles which were placed in the creek have dissolved about 30 % of the mass. The levels of the explosives which are detected are low. The amount of data is, however, not sufficient to conclude regarding the transport of explosives. It is recommended to conduct additional investigations to collect further data.