Swedish tunnel leak "due to sealant overuse"

Potential toxicity of Rhoca Gil was known by Railway Authority, say official investigators

An unacceptably large amount of an acrylamide-based sealant was used during construction of a railway tunnel in the Halland's ridge in southern Sweden last year, an official investigating committee reported to environment minister Anna Lindh on Friday.

Attempts to seal the tunnel with Rhoca Gil, a sealant made by Rhône Poulenc, failed and large amounts of acrylamide leaked into surface and groundwaters, poisoning workers and livestock and leading to an immediate halt to tunnelling work (ENDS Daily 21 October 1997).

In its interim report on the accident, the official Tunnel Commission says that long-term health effects on workers and health risks for local people are both unlikely. But it describes the large quantities of Rhoca Gil used in the operation as "unacceptable from an occupational and environmental health point of view, especially as it had been known for a long time that acrylamide is a chemical with serious toxic effects".

According to the Tunnel Commission, one of the most serious results of the accident is reduced groundwater levels, largely caused by efforts to clean acrylamide from local groundwater so that drinking water wells can be used again. A significant reduction in groundwater levels over 25 square kilometres should be expected, the Commission says.

Up to now, the national railway authority has predicted that groundwater levels will be cut by five metres at most. In its report, the Commission suggests that a 10 metre reduction over a wide area will be needed to clean out all the acrylamide.

Meanwhile, another investigation, ordered by the railway authority, is looking at the environmental effects of the leak and will present its final report later this month. There is also a judicial inquiry underway, investigating the actions of the railway authority and the building contractor for the project, Skanska. Five senior staff at Skanska as well as the former director general of Banverket and the managing director of Rhône Poulenc Sweden, are all under investigation. The judicial inquiry is expected to present its report in the autumn.

Follow Up:
Swedish environment ministry, tel: +46 8 405 1000.

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