Introduction

Innovative chemical-physical-biotechnological process for the remediation of groundwater contaminated by chlorinated solvents, nitrates and sulphates. The process uses polyhydroxyalkanoates as a source of fermentable carbon for the in-situ stimulation of the biological degradation of contaminants. Using recirculating wells, the distribution of the reagents and the action on the portions of the aquifer that are more difficult to reach with traditional systems are facilitated.

Technical features

The process, without wasting groundwater, is carried out by extracting contaminated water through a multi-fenestrated well (Groundwater Circulation Well, GCW) and passing it into an external treatment unit comprising of one reactor that contains the fermentable polymer and one with zero-valent iron, for the removal of extracted contaminants. The fermentation products are reintroduced through the GCW thus distributing the nutrients necessary for stimulating the natural biological activity of the contaminants directly into the aquifer. The process makes it possible to significantly accelerate remediation especially in complex sites. Typically, the remediation takes place through the so-called Pump & Traete systems in which the contaminated water is emitted from the groundwater, treated in an external system and discharged into a surface body. This process makes it possible to significantly speed up the remediation times by acting directly on the sources of contamination without wasting the water resource and via stimulating degradation processes directly in the contaminated area.

Possible Applications

• Remediation of contaminated sites;
• Recovery of abandoned industrial areas.

Advantages

• Acceleration of remediation;
• No depletion of the water resource;
• Significant waste reduction;
• Direct action on the sources;
• Stimulation of degradation processes directly in the contaminated area.