The GSF (Geotextile Sand Filter) advanced wastewater treatment and dispersal system from Eljen Corporation is designed to provide treatment and dispersal in the same footprint, while keeping installations easy and maintenance minimal. Eljen cites independent testing that shows its performance is compliant with NSF/ANSI Standard 40 Protocol, and provides advanced treatment of septic tank effluent to better than secondary levels. 800/444-1359; www.eljen.com.