Liner Integrity Services: Team

Technical Sales

Abigail Gilson, Director of Liner Integrity Services | +1 512 263 5944

Abigail Gilson, M.S., P.E., is the Director of TRI Environmental’s Liner Integrity Services. She has a wealth of experience in geomembrane-lined containment facility design and construction and has performed liner integrity surveys since 2004. As a graduate of TRI’s inaugural liner integrity survey class in 2003, her liner integrity and leak location field experience has exceeded 190 million square feet and over 200 projects. Her contribution to the field of electrical leak location includes numerous published technical papers, educational seminars, presentations world-wide, and chairing the ASTM committee for the recent revisions and additions to the ASTM Standard Guide and Practices. Contact Ms. Gilson for a copy of any of the publications shown below.


A. Gilson-Beck and J.P. Giroud. “A quantification of the short-term reliability of HDPE geomembrane seaming methods”, Geosynthetics International, 0 0:0, 1-5 (2022).
A. Gilson. “Advancements in Field Testing for Locating Geomembrane Installation Damage”, International Journal of Geosynthetics and Ground Engineering, 7:72 (2021).
A. Gilson-Beck. “Dipole Measurement Density and Dipole Spacing for Electrical Leak Location”, Geosynthetics Conference 2021 Proceedings, February 22-25 (2021).
A. Gilson and J. Ferreira. “New Standard Practice for Electrical Leak Location of Covered Geomembranes”, GeoAmericas 2020 Conference Proceedings, Rio de Janeiro, Brazil April 26-29 (2020).
A. Gilson-Beck and L. Shilling. “Construction water flow dynamics of the leak detection layer”, Geosynthetics Magazine, April/May (2020).
A. Gilson-Beck. “Controlling leakage through installed geomembranes using electrical leak location”, Geotextiles and Geomembranes, 47, 697-710 (2019).
A. Gilson. “Electrical Leak Location Testing for Zero Leak Verification”, IFAI Geosynthetics Conference Proceedings, Houston, TX , February 10-13 (2019).
A. Gilson-Beck and J. Ferreira. “Maximizing the Effectiveness of Electrical Leak Location for Covered Geomembranes”, Geosynthetics 2017, First International Conference on Technology and Application of Geosynthetics, 18-20 October (2017).
A. Gilson-Beck and G. Toepfer. “Achieving Zero Leaks on a Budget”, Geosynthetics Magazine, June (2017).
A. Beck and J. Youngblood. “CCR Barrier Systems: Mitigating Risk from Leakage with Proven Advanced Technologies”, World of Coal Ash Conference, May (2017).
A. Gilson. “Best Practices for Groundwater Protection”, GeoAmericas 2016 Conference Proceedings, Miami Beach, Florida, April 10-13 (2016).
A. Beck and C. Kelsey. “Optimizing Geomembrane Performance”, Land and Water Magazine, November/December (2015).
A. Beck. “Electrical Leak Location Sensitivity Explored”,, March 19 (2015).
A. Beck. “Available Technologies to Approach Zero Leaks”, Geosynthetics 2015 Conference Proceedings, Portland, Oregon, February 15-18 (2015).
A. Beck. “Technologies for Reducing the Risk of Landfill Leakage”, Global Waste Management Symposium, Orlando, Florida, June 22-25 (2014).
A. Beck and W. Hornsey. “Leak Detection for Optimum Geomembrane Performance”, 7th International Congress on Environmental Geotechnics Conference Proceedings, Melbourne, Australia, November 10-14 (2014).
J. Ferreira and A. Beck. “Inspeção de Integridade de Liners com Localização Geoelétrica de Furos em Geomembranas: Uma Solução Efetica Para Evitar Contaminações Ambientais e Prejuízos Financeiros”, Fundações & Obras Geotécnicas, pp 60-63 (2014).
S. Prota, D. Parra and A. Beck. “Maximizing Productivity in Heap Leach Pads through Dipole Electrical Leak Location”, Geosynthetics Mining Solutions Conference Proceedings, Vancouver, Canada, September 8-11 (2014).
A. Beck. “The Financial Benefit of Electrical Leak Location to the Mining Industry”, Geosynthetics Mining Solutions Conference Proceedings, Vancouver, Canada, September 8-11 (2014).
A. Beck. “Designing to Minimize Geomembrane Leakage”, Geosynthetics Magazine, August (2014).
A. Beck. “Electrical Leak Location Arc Tester to Revolutionize Liner Quality”,, July (2013).
A. Beck. “Measuring a giant one step at a time”, Geosynthetics Magazine, April (2013).
A. Beck, D. Gallagher and E. Kramer. “Leak Location Liner Performance Evaluation”, GeoSynthetics2013 Conference Proceedings (2013).
A. Beck. “How Much Does my Landfill Leak?” Waste Advantage Magazine, December (2012).
D. Gallagher and A. Beck. “More Accurate Liner Integrity Surveys Using Electrically Conductive Geomembrane”, Geosynthetics Magazine, October (2012).
A. Beck. “A Statistical Approach to Minimizing Landfill Leakage”, SWANA, Washington D.C. Conference Proceedings (2012).
A. Beck. “Case Histories of Exposed Geomembrane Performance”, Geosynthetics Magazine, June/July (2011).
A. Beck. “Technical Improvements in Dipole Geoelectric Survey Methods”, Geo-Frontiers Congress, March (2011).
A. Beck, M. Smith and K. Sample. “Design Considerations for the Use of Geomembranes for Phosphate Tailing Impoundments”, Covaphos3 (2009).
A. Beck and J. LaFerte. “Advancements in Leak Location Technologies for the Control of Geomembranes”, Proceedings of the Environmental and Water Resources Institute conference, Bangkok, Thailand (2009).
A. Beck and R. Hansen. “Electrical Leak Location Surveys for Landfill Caps”, Proceedings of the Environmental and Water Resources Institute conference, Bangkok, Thailand (2009).
A. Beck, M. Smith and E. Kramer. “Specifications for Moisture Content of GCL to Perform Electrical Leak Location Surveys”, EuroGeo4 (2008).
A. Beck and M. Smith. “In Search of the Electric Limit of Geosynthetic Clay Liners”, The Mining Record (2008).
A. Beck. “Comparación de Métodos de Detección Geoeléctrica de fugas para aplicaciones en lixiviación”, Ecoamerica Directorio Provedores Minería (2006).
A. Beck and M. Smith. “A Comparison of Geoelectric Survey Methods for Heap Leach Applications”, Latin America Mining Record, March/April (2006).
A. Beck. “Modern Technology for a Leak-Free Leach Pad”, The Mining Record, March (2006).
M. Smith, A. Beck, R. Thiel, and P. Metzler. “Designing for Vertical Pipe Deflection Under High Loads”, NAGS/GRI-19 Conference Proceedings, (2005).
R. Thiel, A. Beck and M. Smith. “The Value of Geoelectric Leak Detection Services for the Mining Industry”, Geofrontiers Conference Proceedings (2005).

Nadia Minnaar, Geomembrane Specialist | +27 79 875 5691​

Nadia Minnaar, TRI Africa began in 2018 through TRI Africa’s Managing Director Nadia Minnaar. Ms. Minnaar started training with Ms. Gilson in 2014. Ms. Minnaar’s survey experience encompassed over 700 000 m² of covered geomembrane surveys in Africa and North America. Ms. Minnaar’s ELL experience is currently unrivaled on the African continent