New developments in reactive barrier technology

The removal of pollutants from the groundwater using Permeable Reactive Barriers is a novel category of groundwater remediation technologies. The most relevant decontamination processes used are chemical reduction, oxidation, precipitation, sorption and biodegradation, for which examples are given. Some common organic pollutants are halogenated hydrocarbons, aromatic and nitroaromatic compounds which can be treated in reactive barriers successfully. In view of the large number of sites contaminated with lead, chromium and, in particular, uranium in many European countries these inorganic pollutants are dealt with in great detail. Construction methods of reactive barriers exhibit similar features to those of cut-off walls. The most common cut-off wall construction methods are: diaphragm walls, composite cut-off walls, boredpile walls, jet grouting, thin walls, sheet-pile driven walls, injection and frozen walls. Novel reactive barrier construction techniques include drilling, deep soil mixing, jetting, arrays of wells, injected systems, hydraulic fracturing and biobarriers. Permeable reactive barriers bear great future potential in remedial engineering.

• 1 INTRODUCTION

• 2 DECONTAMINATION PROCESSES

• 3 ENGINEERING OF PERMEABLE REACTIVE BARRIERS

• 4 OUTLOOK

• 5 REFERENCES