NTPEP APPROVED - GTX-20 13-0 1-0 30 . GEO 8.0-205NW is a nonwoven needlepunched geotextile made of 100 % polypropylene staple filaments. GEO 8.0-205NW resists ultraviolet and biological deterioration, rotting, naturally encountered basics and acids. Polypropylene is stable within a pH range of 2 to 13. GEO 8.0-205NW will satisfy the requirements as outlined in AASHTO M-288-0 6 for Class 1 applications and meets the following M.A.R.V. values except where noted. Click here for Product Data Sheet.