Close to the E6 in Nordre Follo, Bjørn Gunnar Ganger climbs down a slope and picks up a couple of stones. It is alum slate. – Here there is, among other things, copper, iron, manganese, nickel and uranium. It pollutes the entire area, says Ganger. The leader of SV and the Nature Conservation Association in Nordre Follo meets news at the Taraldrud crossing, a few hundred meters south of the Police’s national emergency centre. Bjørn Gunnar Ganger has fought for years to have the slate removed. Photo: Rolf Petter Olaisen / news Above and below the ground here, there is approximately 50,100 m³ of slate, according to the Norwegian Geotechnical Institute (NGI). Enough to fill over 6,200 trucks. When Ganger presses his fingers against the brittle stones, dark, small pieces flake off. He breaks one stone in two and sniffs it. – It smells of metal, a little bitter, just like the slag heaps in Røros. The shale contains, among other things, cadmium, copper, iron, manganese and uranium. Photo: Rolf Petter Olaisen / news Excavated in Oslo Most of the slate probably comes from various construction projects in Oslo, and was laid here in the 80s and 90s. Among other things, part of the slate comes from the digging of a tunnel under the Stortinget subway station. Some also come from the Dittenkvartalet in Akersgata, which was excavated to make room for the VG building and R5 in the government quarter. Some of the slate comes from the so-called “Dittenhullet”, which was excavated to make room for, among other things, R5 in the government quarter, the Ibsen parking garage and the VG building. This photo is from the summer of 1988. The high block can be seen in the background. Photo: Marit Rasmussen / NTB Nevertheless, it was not until 2006 that the extent of the pollution became clear. E6 was then extended and water samples were taken in the Snipetjernsbekken, which flows nearby. They showed that the water had a low pH value and contained a lot of metals. How much slate actually lay in the area became clear even later. In 2012, the amount was estimated at 30,000 m³, but then the authorities only knew about the shale in the south. In 2017, they discovered that there was even more slate further north, on the Norwegian Public Roads Administration’s property. Some of the alum slate is still found at Taraldrud, but most of it is several meters below ground, mixed with clean soil and stone. Photo: Rolf Petter Olaisen / news Fears for drinking water The shale contaminates the surroundings by rainwater and stormwater from E6 flowing through the underground rock layers. The water carries pollutants out into the Snipetjernsbekken. The water in the stream eventually ends up in Lake Gjersjøen, which is the source of drinking water for approximately 49,500 inhabitants in Oppegård and Ås. Lake Gjersjøen is the source of drinking water for 49,500 inhabitants in Oppegård and Ås. Photo: Rolf Petter Olaisen / news Samples from the waterworks there do not show any contamination from the shale, according to the Norwegian Food Safety Authority. Ganger still believes that the shale poses a danger. – I would describe it as one of Norway’s most dangerous waste dumps. The only thing that is acceptable is that the pollution is removed in its entirety, he says. Nordre Follo municipality also demands that Taraldrud be cleaned up. In a consultation statement, they write that there must be a “final” solution. It must limit the pollution of the stream as much as possible for a long time. The water that is contaminated by the slate landfill at Taraldrud eventually ends up in Lake Gjersjøen, which is the source of drinking water for approximately 49,500 inhabitants in Oppegård and Ås. Will leave most of the slate lying It is the Norwegian Public Roads Administration and the company Åsland Næringspark Eiendom (ÅNE) that own the area where the slate is located. They have got NGI to draw up a plan to solve the problems at Taraldrud. It is now being assessed by the Norwegian Environment Agency and the Directorate for Radiation Protection and Nuclear Safety. The plan recommends the following measures: To remove approximately one third of the slate, 18,000 m³, from the National Roads Administration’s site, in the north of the area. Leave the slate in the south. Dig a trench between E6 and the remaining slate. This will prevent water from the motorway from flowing through the slate and carrying pollution with it. Maintain cleaning ponds between the shale and Snipetjernsbekken. These will capture contamination from the remaining shale. The ponds must be maintained indefinitely by the landowner. The shale lies above and below the ground in the pink area. The dashed red line is the border between the Norwegian Public Roads Administration’s property and the plot of land for Åsland Næringspark Eiendom. The plan recommends removing the slate in the north, but leaving the slate in the south. Between E6 and the slate in the south, a ditch must be dug to prevent water from the road from flowing through the slate. Between the shale and Snipetjernsbekken in the west, ponds will capture the remaining pollution. Graphic: Norwegian Geotechnical Institute It is not a permanent solution, Ganger believes, because it will require follow-up of the purification ponds for an indefinite period of time. – Then you are dependent on future budgets and priorities from the landowner. Removing just one third of the slate will cost at least NOK 140 million. No one knows how much it would cost to remove all the slate. Ganger still believes that it is worth paying to stop the pollution and secure the drinking water. The sludge in the cleaning ponds between the shale and Snipetjernsbekken contains so much uranium that it is categorized as radioactive waste. Ganger believes the dam solution is not good enough. Photo: Rolf Petter Olaisen / news – Digging everything up is a bad solution The shale that can remain is on ÅNE’s site. They believe that all possible measures have been carefully considered, including removing all the slate. – This is not a matter where you have jumped at the easiest solution, says development director John Mjøen at Relog AS, which owns ÅNE. John Mjøen is development director at Relog AS, which owns Åsland Næringspark Eiendom. Photo: Bård Nafstad / news Clearing all the slate is difficult because it is not in clumps that can be easily dug up, he explains. It is mixed with large quantities of clean soil and stone, which do not pollute. According to Mjøen, it is almost impossible to separate the alum slate from the pure soil. Then they would have had to dig up a lot of clean soil to remove the slate. All this earth will cost a lot to transport away. In addition, it will be difficult to find a place to dispose of it safely. – Digging up everything that is not really contaminated is a bad solution, says Mjøen. It may take several years before the work starts, the Norwegian Public Roads Administration owns the northern part of the area, where it is recommended to remove all the slate. Here the alum slate is more concentrated and is easier to dig up. It is also this part of the slate that pollutes the most. – We are keen to clean up our property, and will do so as far as possible, says planning manager Thorstein Hymer in the Swedish Road Administration. Planning manager Thorstein Hymer in the Norwegian Public Roads Administration Photo: Vegar Erstad / news They need at least a year to plan the work, according to Hymer. In addition, it is unclear when funding for the work will be available. Now the landowners are waiting for what the Norwegian Environment Agency and the Directorate for Radiation Protection and Nuclear Safety decide. The Swedish Road Administration and ÅNE can be required to implement the plan, but the authorities can also order them to take other measures. The Norwegian Environment Agency says they cannot give a date for when a decision will be made in the matter. The landowners will leave most of the alum slate at Taraldrud lying. Photo: Rolf Petter Olaisen / news
ttn-69
Slate with metals and uranium dumped at Taraldrud, contaminates stream that flows into drinking water – news Oslo og Viken – Local news, TV and radio
