Pilot test of Steam-Air-Injection in the saturated zone for the remediaton of CHC at a site in Durlach, Germany

In the context of the pre-design of a groundwater remediation measure in Karlsruhe Durlach according to German soil law (BBodSchV) the innovative in-situ remediation technique of steam-air injection was applied close to the source zone of a CHC-contaminated site during a 3 months lasting pilot study. The pilot study was executed by VEGAS on behalf of the environmental agency of the city of Karlsruhe. Responsible for surveillance and the final site remediation design was the consultancy dplan.

Aim of the pilot study was the determination of the site-specific thermal radius of steam-air injection in the saturated zone. The radius of steam propagation was over 3 m radius which was in accordance to the accompanying numerical simulation of the steam propagation for an anisotrop layered aquifer (Ochs, S.O., 2006).

The steam zone was maintained for 4 weeks of steam-air injection period (120 kg/h of steam and 20 kg/h air) to remediate the capillary fringe by steam-induced convective heating and simultaneously evaporate the contaminants from a highly contaminated silt layer located in the unsaturated zone by conductive heat transfer. In total 450 kg of perchlorothene (PCE) were removed.

Based on the promising pilot study the full scale remediation (> 1000 m³ of affected soil) under the historical building was designed and the costs were estimated. As financial and time savings aspects clearly indicated advantages of the thermal technique compared to state-of-the-art technologies like the combination of pump-and-treat, air-sparging and soil vapour extraction a steam-air remediation approach is planned fort he years 2009 and 2010.

For further information concerning the pilot trial please have a look at the following publication.
Poster contribution and Talk: Oliver Trötschler & Hans-Peter Koschitzky, Session 23 at 2nd International Conference on Managing Urban Land, REVIT&CABERNET, April 25th - 27th 2007 Theaterhaus Stuttgart, Municipality of Stuttgart

Koschitzky, Hans-Peter

Trötschler, Oliver

VEGAS

From: 2005-03-01

To: 2006-03-31

Stadt Karlsruhe