Long ago ago hydroelectricity attracted energy intensive manufacturing to the canton of Valais, much of it along the banks of the Rhône river. These activities, which include aluminium smelting, synthetic fertiliser production and chemical manufacture, boosted the local economy but have also left a legacy of pollution that continues to affect the river and ground water in the canton.
Pollution from these industries was poorly managed up until the end of 1970s when laws and practises changed. Some dumpsites have been cleaned up, however, much of the pollution from this era remains, according to RTS.
A recent RTS documentary reveals the scale of the problem. The list of pollutants includes benzidine, mercury, perfluorine, chlorothalonil and chlorinated solvents. These substances continue to escape from chemical dumpsites along the river banks of the river Rhône, making their way into the river and ground water.
Across all of Switzerland, there are around 38,000 polluted sites, of which around 4,000 risk polluting ground water. The canton of Valais is home 130 sites that require clean up including a number of large notable dumpsites, which include a park in Monthey contaminated with chrome and mercury, a waste dump in Sierre and a dumpsite the size of 40 football pitches in Gamsenried near Brig containing benzidine, a substance associated with cancer.
To clean up the site in Monthey, contaminated soil is being sent to special facilities for decontamination and air is being injected into the ground to promote the growth of pollution-eating bacteria. However, in 2021, soil tests at the former dumpsite revealed excess levels of chrome and mercury levels 10 times the tolerable limit. Currently there is no clear plan for cleaning up the site. The municipality is aiming to come up with a plan by 2022. The commune also has to deal with an even larger area of contamination where chemical manufacturers continue to operate that also affects ground water.
Until 2006, the municipality of Ollon across the river from Monthey, drew its town water from ground water near the Rhône until it discovered the water contained levels of toxic substances above tolerable limits. In 2015, the commune received CHF 5 million in compensation from the chemical industry, a small sum compared to the CHF 35 million cost of replacing the town’s water supply with water from higher altitudes.
A key challenge is establishing responsibility and reaching agreement on who will pay for the clean up. It can be difficult to establish proof of events that took place long ago.
Another site near Sierre contains toxic fluorine and arsenic from aluminium production in the 60s. The current land owner, who had nothing to do with the pollution, is now on the hook for much of the cost of clean up and says the cost will bankrupt his company.
Further up the valley is the huge waste dump at Gamsenried near Brig. This site contains anilines, heavy metals and benzidine. Benzidine is toxic at very low levels of concentration and passes easily through the skin. The substance is associated with increased risk of bladder and pancreatic cancers. Efforts have been made to contain the substance, however it sometimes escapes into the ground water. In 2018, contaminated water was pumped from the ground and released into the river without authorisation during the construction of river diversion, according to a former head of the environmental agency in Valais.
Some have criticised chemical companies for knowingly ignoring the problem. The benzidine problem has been known for a decade, according to Martin Forter, a medical expert. But chemical companies preferred to bury the fact. This has delayed the clean up, said Forter. Another says that the dangers of the chemical were probably not fully understood at the time.
Forter argues that large chemical companies have become wealthy off the back of a history of pollution and can easily afford the costs of clean up. The waste dump at Gamsenried would cost between CHF 1 and 1.5 billion to clean, a sum the industry could easily swallow. However, the industry view isn’t aligned with Forter’s.
Switzerland has become wealthy in large part from its success in the chemical and pharmaceutical sectors. Companies that started manufacturing ordinary products like dyes and fertiliser have innovated their way to becoming global giants in the chemical and drug sectors.
However, progress on cleaning up past pollution, arguably hasn’t followed the same trajectory. As the ongoing political battle around who is responsible and who will have to pay continues, it seems that only minimal efforts and budgets are likely to be applied to the clean up of past waste.