This page was printed from

GSI’s second Inspector Certification Program

News | August 1, 2011 | By:

In 2006, GSI launched its first inspector certification program for the installation of geosynthetics at waste containment facilities.

To be a successful candidate, the individual must provide an application verifying six months of related experience, an employer’s recommendation, and completion of a multiple-choice examination with a 70% passing grade. To date, 422 people are certified for quality assurance of geosynthetics and 388 are certified for compacted clay liners. The program has been established to the point that several waste owners and state environmental agencies require GSI-certified inspectors for their projects.

That said, a quite different geosynthetics-related area is a major concern of owners, regulators, designers, and almost everyone involved in geosynthetics—the incidence of failures of mechanically stabilized earth (MSE) walls, berms and slopes. Such MSE structures are reinforced with either geogrids or geotextiles and have other associated geosynthetic materials in them as well. The failures within our data base of 103 case histories are in two distinct categories:

  • excessive deformation (26 cases).
  • actual collapse (77 cases).

The basic failure mechanisms were placed into four different categories as shown:a) Internal instability (24%)b) External instability (12%)c) Internal water (44%)d) External water (20%)

New course testing and dates

The concern regarding this situation has brought about a second GSI Inspector Certification program, this new one for MSE walls, berms and slopes. To date, with the help of the following steering committee, we have assembled an eight-hour course and more than 100 questions and answers: Kent von Maubeuge (NAUE Geosynthetics), Mohammed Karim (Virginia DEQ), Bob Sabanas (NTH Consultants), John Conturo and Maria Tanase (AECOM), John Lostumbo (TenCate Geosynthetics), Mike Yako (GEI Consultants), Steve Poirier (Geosyntec Consultants), Willie Liew (Tensar International), Doug Clark (CEC Consultants), Dick Stulgis (Geocomp Consultants), Frank Adams, Paul Whitty, and Rafael Ospina (Golder Associates), Daniel Alzamora (FHWA), Sam Allen (TRI Environmental), Greg Cekander (Waste Management), Greg Fedak (CETCO Contracting).

A pilot course for the steering committee is set for Sept. 15, 2011, at GSI with course attendees taking the examination. We will make required modifications to the course and the Q’s & A’s and then begin with open courses and examinations for everyone interested this winter. The dates are Dec. 1, 2011, and March 14, 2012, at GSI.

Criteria for a successful applicant are: six months of experience with construction of MSE structures, an employer’s recommendation, and 70% passing grade on the examination. The fee for certification is $500 for a five-year period and information is available on our website: at “Certification/MSE Walls, Berms and Slopes.”

While a field inspector cannot require proper design, flaws can be identified for possible design modification or mitigation action. Furthermore, and at minimum, construction practices can be observed and corrected if inadequate or improper. Please contact George Koerner at or Bob Koerner at for questions or additional information.

Bob Koerner, Ph.D., P.E., NAE, is the director of Geosynthetic Institute (GSI) and is a member of Geosynthetics magazine’s Editorial Advisory Committee. GSI: +1 610 522 8440.

Share this Story

Leave a Reply

Your email address will not be published. Required fields are marked *

Comments are moderated and will show up after being approved.