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 D. Geotextiles
1. Background
Geotextiles are permeable civil engineering fabrics used in a variety of construction
applications. The four main functions of a geotextile are separation, drainage, filtration, and
slope reinforcement. Depending on the application, a geotextile may serve one or more of
these functions. The five main applications for geotextiles are: road building, drainage,
erosion control, soil stabilization, and waste containment (e.g., landfill construction).
Geotextiles may be made of woven or nonwoven fabrics. Woven geotextiles
generally are stronger than nonwoven fabrics of the same weight, and dominate the drainage,
asphalt overlay, and lining systems markets. Nonwoven geotextiles generally are permeable
to moisture, resistant to rot and mildew, and conform to the subgrade soils. Nonwoven
fabrics dominate the stabilization and separation, and subgrade and base reinforcement
markets.
In the CPG, EPA proposed to designate geotextiles for use in road building, drainage,
erosion control, and soil stabilization, and for use in the gas collection layer and the
protection layer between the drainage stone and the geomembrane liner in waste containment
systems (see 59 FR, 18871, April 20, 1994).
2. Summary of Comments and Agency's Response
Although many commenters supported the proposed designation of geotextiles, the
majority of commenters opposed it.
a. Polyethylene terephthalate geotextiles. Those in support of the designation stated
that there are non-woven geotextiles available made with postconsumer recovered
polyethylene terephthalate (PET) and they are being used in a variety of applications. These
commenters also stated that adequate performance testing has been conducted to justify the
designation of geotextiles made with recovered materials.
b. Performance and polypropylene geotextiles. Commenters opposed to the proposed
designation of geotextiles expressed concern that using recovered resins in geotextiles could
result in catastrophic features if used in critical applications, such as in landfills or in road
construction. These commenters stated that evidence does not exist on the long-term
performance of geotextiles made with recovered resin or on the chemical compatibility of
geotextiles containing recovered materials when used in landfill applications. Additional
commenters claimed that no manufacturers actually make geotextiles with postconsumer
polypropylene, that the technology does not exist to make geotextiles with recovered
polypropylene, and that high-quality postconsumer polypropylene is not available in sufficient
quantities for use in making geotextiles.
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