Soil and Groundwater
Like many other long-standing chemical companies, WACKER has some soil contamination on its premises. In the pioneering days of chemical production, nobody was aware of the dangers posed by certain chemicals, or that some substances could persist in the ground for extended 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. To date, 1,957 metric tons of chlorinated hydrocarbons (CHCs) have been removed in this way. As soil treatment progresses, the amount of contaminant removed decreases, as is to be expected. In 2012, only 18 metric tons were removed (2010: 23 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 2012, 28 metric tons of CHCs had been removed; pollutant concentrations have been reduced to one sixth of their original levels. In order to reduce the discharge of hexachlorobutadiene (HCBD) into the tailrace, we are continuing groundwater treatment of the site’s contaminated areas. Currently, 73 kg of the pollutant is being removed per year. The results of our fish contaminant survey at Burghausen indicate that the fish are quite safe to eat.
Additionally, there is some groundwater contamination at our Nünchritz site. This predates WACKER’s takeover of the site. We have been cleaning up the groundwater there since 2009 and have been using a hydraulic process since 2012. The process involves pumping the groundwater into a treatment system, and returning it to the ground after purification. By the end of 2012, we had cleaned a total of 65,000 cubic meters of groundwater there.
In partnership with NW Natural (formerly Gasco), Siltronic in Portland financed a design for the remediation of the banks of the Willamette River, which flows past the premises of both companies. This area contains residues of, for example, oil and tar, which were deposited there before the site’s acquisition by Siltronic.
Prior to 1973, chlorinated hydrocarbons were stored in a chemical warehouse in the southern part of Düsseldorf. For reasons that remain unclear, some of these substances contaminated the soil and groundwater. At the time, the warehouse was rented by a freight forwarder; Deutsche Bahn (Germany’s national rail company) owns the site. Together with the forwarder from that time, WACKER organized and financed an inspection of the soil and groundwater in preparation for an effective remediation program. WACKER carried out these measures from 2011 to 2013 in consultation with Düsseldorf’s Environmental Agency. We are still convinced that we did not cause the contamination.