Groundwater Control

Groundwater control technologies include a variety of applications. These barriers are designed to stop groundwater from migrating into a construction zone or from transporting hazardous substances downstream. The most common application includes subsurface barriers constructed using the slurry trench method. Slurry trenches are normally constructed with hydraulic excavators and their widths can vary from 1.5 to 5.0 feet. Excavations greater than 100 feet deep require the use of a crane and clam bucket, or other specialty equipment. In most cases, the excavation is "keyed" 2 to 3 feet into a low permeability stratus such as clay or bedrock to assure minimal leakages under the final wall. It is common for the trench to be backfilled with a mixture of excavated soil, dry bentonite, and bentonite slurry. The backfill is placed into the end of the slurry trench, in a manner than displaces the slurry forward, toward the ongoing excavation and continues until the barrier wall is complete.

Containment System

RECON installed a secondary product containment system around the perimeter of a terminal storage unit facility to prevent any product from migrating off the property. RECON used both the Slurry Trench and Jet Grouting techniques to complete this project.

Project Features

• Slurry Trench: RECON excavated 3,400 linear foot wall, 1 foot wide, to depths ranging between 6 and 14 feet below the ground surface. The wall was excavated under ImpermixTM slurry.
• Jet Grouting: RECON used a jet grouting rig to reach the inaccessible areas of the property. The total length was 200 linear feet. ImpermixTM was injected at a low-pressure rate, not exceeding 3,500 psi.