Sammendrag
Monitoring in 2017 comprised two‐three rounds of water sampling for determination of water chemical variables and heavy metals in surface run‐off from the following disused ranges for military shooting and exercise: Gimlemoen, Marka, Fredrikstad, Avgrunnsdalen, Gurulia/Bue‐Nebb, Banemyra, Børja, Kvamskogen (Steinskvanndalen), Ørskogfjellet, Melbu/Haugtuva, Skarsteindalen, Kjoselvdalen, Kvenvikmoen og Nyborgmoen. The intention is to collect data that can be used to assess the need for curbing aquatic pollution and to document the effect of clean‐up operations. At the ranges of Gurulia, Gimlemoen and Banemyra there are indications that measures taken to lower heavy metal concentration in run‐off have had effect. The monitoring of these ranges should proceed in 2018 to find out if the downward trends continue. At the Bue‐Nebb range mitigating measures have reduced heavy metal concentration to acceptable levels and monitoring can be terminated. It is considered unlikely that the effect of the mitigating measures on heavy metal leaching from the Marka range can be documented, and it is suggested that monitoring here can be terminated. Like Marka the range at Fredrikstad has little surface run‐off, and changes in heavy metal levels after clean‐up operations are not evident. However, another year of monitoring of run‐off from Fredrikstad is recommended because heavy metal levels are somewhat higher than at Marka. At the Ørskogfjellet, Kvenvikmoen and Kjoselvdalen ranges, clean‐up operations were undertaken in 2017. The effect of these should be monitored in 2018. Run‐off from the Nyborgmoen and Melbu ranges have been monitored for 2‐5 years, and concentrations have been low. Further monitoring can be postponed until clean‐up operations commence. At the Skarsteindalen range as well, the situation prior to clean‐up is well documented. At the Børja range, monitoring should proceed to collect more data.