Soil remediation

from Wikipedia, the free encyclopedia

With a soil remediation pollutants from contaminated soil removed. Such substances are - depending on the industrial use - z. B. heavy metals, mineral oil or polycyclic aromatic hydrocarbons (abbreviated: PAK or PAH).

Procedure

Depending on the pollutant, different processes can be used:

Inorganic pollutants (e.g. heavy metals ) can be extracted using chemical-physical processes, e.g. B. by:

  • Extraction of the pollutants with a washing liquid (surfactants and / or organic solvents). Since this usually does not run off completely, high pressure extraction can be used, in which compressed gases are used as extraction agents , such as. B. carbon dioxide , or
  • Phytoremediation with the help of suitable plants, e.g. B. absorb cadmium or chromium in the root area accumulate in their leaves.

Organic pollutants (e.g. mineral oils , solvents, PAHs) can also be broken down, e.g. B .:

  • thermal, whereby the contaminated material is incinerated in rotary kilns at over 1100 ° C with a downstream exhaust air purification, or
  • microbiological , using extremophilic organisms, or
  • using a washing process.
  • Highly volatile substances (solvents, e.g. gasoline, benzene or chlorinated hydrocarbons, e.g. Per or Tri) can also be removed by means of soil air extraction.
"Landscaping" at Lake Phoenix (Dortmund)

This can be done on the contaminated site itself ( on-site ) - by means of mobile treatment systems or without excavating the soil ( in-situ ) - or off-site by transporting the contaminated soil to a corresponding soil treatment system. But they are cheaper and therefore far more common

These so-called landscaping structures are becoming more and more numerous, e.g. E.g. the TriMonte Park on Wiemelhauser- / Wasserstraße in Bochum (formerly Maschinenfabrik Mönninghoff ), on Phoenix-See in Dortmund (formerly Thyssen-Krupp) or on Weidestraße in Hagen (formerly Varta) (see photo). In fact, the contaminated soil is dumped on the company's own site.

National limit values

Germany

For excavation
Contaminated soil material that must be disposed of is waste. Before it is removed, however, the possibility of recycling must be checked, Section 6 KrWG. This is done by means of the so-called assignment values ​​Z0 to Z2 of LAGA notification M20 ( regional working group on waste ): Each Z-class comprises a series of limit values ​​for different substances, both for their total content and for the water-soluble fraction (eluate). If all Z0 values ​​are adhered to, the floor can be used for all possible uses ("open installation"). If the other Z-classes are exceeded, the use is restricted more and more.
For untouched ground
The limit values ​​of the Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV), Appendix 2, apply to assess the soil quality on site (without excavation). It specifies several limit values ​​for each substance, depending on the type of soil (clay, loam / silt , sand) and use (Children's play areas, residential areas, parks and leisure facilities, industrial and commercial properties).

Competent bodies

This section needs to be revised. Details should be given on the talk page. Please help to improve it , and then remove this flag.

The State Office for Nature, Environment and Consumer Protection (LANUV) is responsible for the investigation and remediation of contaminated sites in North Rhine-Westphalia .

The reports that are not publicly available can be viewed on the Internet.

literature

  • I. Reiss, A. Schleußinger, S. Schulz: Soil sanitation through high pressure extraction, chemistry in our time , 28th year 1994, No. 4, pp 189-196, ISSN  0009-2851
  • Stegmann (Hrsg.): New techniques of soil cleaning - chemical-physical and biological process development taking into account the soil science and analytical evaluation, documentation of the 3rd SFB 188 seminar in Hamburg . Economica Verlag, Bonn 1996, ISBN 3-87081-186-2 .

See also

Individual evidence

  1. ↑ List of pollutants to be expected in a specific industry, Bavarian State Office for Environmental Protection, 03/2004: http://www.lfu.bayern.de/altlasten/schadstoffratgeber_gebaeuderueckbau/suchregister/doc/511.pdf
  2. ↑ Soil poison disappears in the landscape structure , WAZ, February 25, 2013: http://www.derwesten.de/staedte/hagen/bodengift-verschwindet-im-landschaftsbauwerk-id7658716.html
  3. ↑ Allocation values ​​(LAGA M20), Landfill Ordinance, Lower Saxony Society for the Final Storage of Sonderabfall mbH, Hanover, 05/2013: http://www.ngsmbh.de/bin/pdfs/Zuordnungswerte.pdf
  4. ↑ Federal Soil Protection and Contaminated Sites Ordinance of July 12, 1999 ( Federal Law Gazette I p. 1554 ), last amended by Art. 5, Paragraph 31 G v. February 24, 2012: https://www.gesetze-im-internet.de/bundesrecht/bbodschv/ overall.pdf
  5. ↑ State Office for Nature, Environment and Consumer Protection of the State of North Rhine-Westphalia (LANUV), soil protection and contaminated sites , accessed on May 10, 2016
  6. ↑ Ask the state