Contaminated sites: In brief

Switzerland has around 38,000 landfill, industrial and accident sites which are polluted with substances and waste that could pose a danger to the environment. These are all listed in a special register, or cadastre. More than 1,800 sites classified as contaminated have been remediated to date. The target of completing all necessary remediation work by 2045 is unlikely to be achieved. The current revision of the Environmental Protection Act (EPA) is intended to speed up this process.

1. Uncontrolled waste disposal (drivers)

Old landfills, polluted industrial areas and sites where accidents occurred bear witness to uncontrolled handling of wastes in the past. Waste disposal and treatment were dealt with as cheaply as possible. At the time, however, environmentally-friendly waste disposal was not always possible. For example, combustible hazardous wastes were dumped into worked-out gravel pits, or toxic production residues were discharged onto unsealed ground within plant compounds.

Current legislation should ensure that no new contaminated sites are created, with the exception of unpredictable events like accidents.

2. Escape of hazardous substances into the environment (pressures)

Hazardous substances can escape into the environment from landfills, plants, shooting ranges or accident sites.

  • Pollutants from such deposits commonly leach into underground or surface waters. Sixty per cent of the polluted sites are located in water protection areas, i.e. above useable or used groundwater bodies.
  • Pollutants end up in the soil (e.g. heavy metals such as lead and antimony at shooting ranges).
  • Other sources of pollution are gases emitted into the air from municipal landfills.

3. Number of polluted sites (state)

There are approximately 38,000 polluted sites in Switzerland. Just under 50% of these are industrial sites, almost 40% are landfill sites, around 10% are firing ranges and shooting ranges, and 1% are accident sites.

Assessments by the enforcement authorities show:

  • Around 53% of all polluted sites do not need to be investigated further, as no environmental impacts are to be expected.
  • For about 29% of the sites, investigations showed that there was no need for monitoring or remediation.
  • About 11% of all sites (4,300 sites) still need to be investigated.
  • It may ultimately be assumed that approximately 4,000 sites pose a threat to humans or the environment, in other words they are contaminated sites and must be remediated.

Some 1,800 of the estimated 4,000 contaminated sites have been remediated. Remediation is underway at most of the sites that require it urgently. Work has been completed, for example, at the Pont Rouge landfill in Monthey and the large Bonfol and Kölliken hazardous waste landfills.

4. Environmental contamination, danger to the public, high remediation costs and economic losses (impact)

Hazardous substances escaping into the environment from a contaminated site can cause acute or chronic illness in human beings.

Such substances are also a threat to water, soil and air. The impact is most often seen in the groundwater.

Contaminated sites are a grave problem for Switzerland in particular, because population density is very high here. Many polluted sites, moreover, lie in the immediate vicinity of sensitive groundwater formations.

Certain substances are quite mobile and long-lived. Fortunately, however, there are also numerous pollutants that are degraded by natural processes over a span of years or a few decades.

One estimate puts the aggregate cost of cleaning up contaminated sites at roughly CHF 5 billion.

5. Contaminated site management (responses)

The federal authorities are committed to ensuring that no dangerous contaminated sites will be passed on to future generations. The Environmental Protection Act (EPA) and Contaminated Sites Ordinance (CSO) provide the legal basis for the work of the FOEN in this regard.

Thanks to the OCRCS Contamination Fund, the federal authorities can provide support for the remediation of contaminated sites to the tune of up to CHF 40 million annually. The FOEN ensures that the risks to humans and the environment arising from contaminated sites can be eliminated in the long term and sustainably in accordance with the principle of dealing with pollution at source.

It is foreseeable that the federal government's target of having completed all investigations by 2028 and all necessary remediation work by 2045 will not be reached. The timeframe for remediation of contaminated sites as well as financial support from the federal government are to be regulated in a more binding manner. At the same time, further details will be provided on the approach to the various polluted areas where children play, which is not covered by the Contaminated Sites Ordinance. In autumn 2021 the Federal Council thus referred this revision of the Environmental Protection Act (EPA) for consultation. The corresponding results report dated 16 December 2022 is available.

Thanks to the legislative provisions on waste management, which were enacted by the federal authorities in the 1990s, no more contaminated sites should arise in future:

  • These provisions include, for example, the regulations on the prevention of landfilling of hazardous waste and the ban on the disposal of untreated municipal solid waste in landfills from 2000.
  • The infrastructure for recycling and treating waste prior to disposal was developed at the same time.

Further information

Last modification 27.04.2023

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