Investigators range from Økokrim, Norway's anti-fraud office, and a transport ministry expert group, to local police departments, environmental NGOs and ad hoc associations of academics, scientists and local residents affected by the project.
The State Pollution Control Authority (SFT) is conducting its own inquiry, as is the Norwegian Water Resources and Energy Administration (NVE) and virtually every government department with any environmental or health and safety responsibility.
Bård Bergfeld of the environmental group Bellona told ENDS Daily today: "We think there are going to be some heavy fines, and some of these guys may even go to jail." Although local environmental pollution from improper use of three toxic chemical sealing compounds had made the headlines, he added, the threat to the health of construction workers was likely to emerge as a more serious issue.
The sealants involved are the acrylamide compound Rhoca Gil (also marketed as Siprogel), which has now been banned by the SFT, and two polyurethanes, TACSS and Resfoam, containing isocyanates and dibutylphthalate (DBP).
Last month, within days of the announcement that local drinking water restrictions had been imposed, following the discovery of unsafe levels of the toxic chemical acrylamide in several private wells, Bellona disclosed that 14 tonnes of TACSS and about four tonnes of Resfoam had been used at the same site earlier this year.
Bellona chemical engineer Christian Rostock told ENDS Daily that both isocyanates and DBP are toxic chemicals. The former, he said, is a potential allergen, which damages the lungs and liver, while the latter has been associated with hormonal and reproductive disturbances.
Mr Bergfeld added: "The compounds are safe enough when used correctly. That means respiratory and skin protection for the employees and regular monitoring of air concentrations in enclosed working areas. None of these measures appears to have been taken in the tunnel."
For the duration of the winter, only concrete is being used in the tunnel, although chemicals may be used again in the spring in an attempt to stop a series of torrential leaks, which are draining a number of lakes in Østmarka, part of the huge forested region surrounding the capital and a popular recreational amenity.
Bellona, tel: +47 22 38 24 10.
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