Technical Papers

INSTALLATION OF A DEEP DRAINAGE TRENCH BY THE BIO-POLYMER SLURRY DRAIN TECHNIQUE
NWWA – 1988
Richard Hanford
Steven Day

Editors Comments:
This was the first technical paper written describing the use of the bio-polymer trench technique for the collection of contaminated groundwater. The paper is primarily a case study describing a 50 ft deep by 800 ft long french drain installation in California. The paper also describes the properties of guar gum as a bio-polymer slurry. The benefits of the technique and the construction methods are explained.

Original Abstract:
Deep drainage or interceptor trenches can be used to collection and contain groundwater-borne contaminates. In the past, such trenches have seen limited applications on deep waste containment projects due to the problems and costs associated with trench bracing, dewatering, and working in confined, hazardous space.

This paper examines a newly developed technique, which permits the installation of deep interceptor trenches by a version of the slurry trench technique, which uses a biodegradable agent instead of bentonite to create a continuous aggregate-filled trench.

Experience during and after the project showed the deep drainage trench to be an effective, safe and economical means of installing a drain for controlling contaminated groundwater.