Dr. Timothy D. Stark of the University of Illinois at Urbana-Champaign and the Fabricated Geomembrane Institute (FGI) has published a guideline to clarify the PVC Geomembrane Fabrication and Installation Specification prepared by the PVC Geomembrane Institute (PGI) in 2006. The FGI grew out of and assumed the PGI’s work. The updated seam specification was published in late January 2010. Download the document for free in PDF.