Soil and Groundwater

GRI 306-3
Wacker Chemie AG - Sustainability Report 2015/16

Like many other long-standing chemical companies, WACKER has some soil contamination on its site premises. In the pioneering days of chemical production, nobody was aware of the dangers posed by certain chemicals, or that some substances could remain in the ground for prolonged periods without undergoing degradation.

To remediate this legacy of contamination, WACKER has been extracting air from the soil at the Burghausen site since 1989. This predominantly removes highly volatile halogenated hydrocarbons from the soil, which are then incinerated to render them harmless. By the end of 2016, we had removed a total of 2,041 metric tons of ; the amount of contaminants removed in 2016 was 19 metric tons.

Since 2003, we have been using a groundwater stripping plant to treat an area of localized groundwater contamination east of the Burghausen site. By the end of 2016, 31 metric tons of CHCs had been removed; pollutant concentrations have been reduced to one tenth of their original levels. In order to reduce the discharge of into the tailrace, we are continuing groundwater treatment of the site’s contaminated areas. Currently, 92 kilograms of the pollutant is being removed per year. The results of our annual fish contaminant survey at Burghausen indicate that fish from the Salzach river are quite safe to eat.

There is some groundwater contamination at our Nünchritz site, too. This predates WACKER’s takeover of the site and has already been cleaned up by means of temporary measures. A remedial investigation is currently underway to devise a concept for further remediation measures. In addition, we are revising a concept for flood protection at the Nünchritz site in close collaboration with local authorities.

Siltronic’s Portland site in Oregon, USA, has developed a method of biodegrading trichloroethylene (TCE) residues in groundwater by means of microorganisms. With this method, which has been approved by the Oregon Department of Environmental Quality (ODEQ), we almost completely eliminate trichloroethylene from groundwater and thus achieve drinking water quality. The US Environmental Protection Agency (EPA) has recognized our biological method of degrading chlorinated (CVOCs) with which we eliminate 90+ percent of these substances.

Chlorinated Hydrocarbons (CHCs)
Organic compounds containing chlorine. They are used, for example, in the manufacture of plastics and solvents. CHCs are chemically stable and fat-soluble; some of them are environmental toxins.
Hexachlorobutadiene (HCBD)
A chlorinated organic compound which, at room temperature, is a colorless liquid with a mild odor. It occurs as a by-product in certain chemical production and combustion processes, such as the synthesis of tetrachloroethene, trichloroethene or carbon tetrachloride. The EU’s water framework directive classifies HCBD as hazardous. The results of the European Emission Inventory show that most of the reported emissions originate from bulk production of basic organic chemicals.
Volatile Organic Compounds (VOCs)
Volatile organic compounds (VOCs) are gaseous and vaporous substances of organic origin that are present in the air. They include hydrocarbons, alcohols, aldehydes and organic acids. Solvents, liquid fuels and synthetic substances can be VOCs, and so can organic compounds originating from biological processes. High VOC concentrations can be irritating to the eyes, nose and throat and may cause headaches, dizziness and tiredness.