Geosynthetics can be defined as planar products manufactured from polymeric material, which are used with soil, rock, or other geotechnical engineering-related material as an integral part of a manmade project, structure, or system (ASTM, 1995). Geosynthetics are widely used in many geotechnical, environmental, and hydraulic applications related to groundwater quality and control. One of the most common examples is the use of geotextile filters in trench (i.e., French) drains.
Base and cover liner systems for modern landfills also make extensive use of geosynthetics with the main purpose of minimizing the potential for groundwater contamination. Furthermore, the use of geosynthetics is rapidly increasing in applications related directly to groundwater control. This is the case of high density polyethylene (HDPE) vertical barrier systems, which can be used instead of traditional soil-bentonite cutoff walls in projects involving groundwater remediation and control.