On-demand Webinar

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This webinar was co-sponsored by ASCE's Geo-Institute (G-I) and ASCE Continuing Education

Instructor:  Craig H. Benson, Ph.D., P.E., F.ASCE, D.G.E, NAE

Course Length: 1.5 Hours

Geosynthetic clay liners (GCLs) are used worldwide as hydraulic barriers in waste containment facilities, heap leach pads, ponds, canals, and other related engineered works. Acceptance of GCLs during the last 30 years has been rapid because these products offer many advantages over compacted clay liners, not the least of which is lower cost for many applications. However, testing and design using GCLs is more difficult than for any other geosynthetic material. In this webinar series, fundamental and advanced topics for engineering with GCLs are discussed and design methods are presented, with emphasis on waste containment applications. This webinar presents fundamental and advanced topics for hydraulic and chemical performance of GCLs in landfill bottom liner systems.

Purpose and Background

The two most essential requirements of GCLs are acceptable performance for hydraulic containment and stability. Hydraulic conductivity and chemical compatibility of GCLs has received much attention in the last decade as research has indicated that hydraulic containment performance is strongly dependent on chemical environment, wetting/drying history, and overburden stress. Likewise, shear strength of GCLs has also been the subject of numerous recent investigations involving large displacements, high overburden stress, dynamic loading, and geomembrane protection from coarse soil subgrades.

Primary Discussion Topics

  • Hydraulic conductivity of soils and GCLs
  • Hydraulic conductivity and chemical compatibility tests for GCLs under high confining stress
  • Environmental factors and GCL performance in liner systems
  • Design of GCLs in liner systems
  • Case histories
  • Conclusions
  • Questions

Learning Outcomes

Upon completion of this course, you will be able to:

  • Recognize GCL hydration interactions affect chemical compatibility in liners
  • Identify how leachate characteristics affect the hydraulic conductivity of GCLs
  • Identify how stress affects the hydraulic conductivity of GCLs
  • Identify how to predict chemical interactions that affect GCLs
  • Recognize design methods to protect GCLs in liners
  • Determine performance expectations from field data

Webinar Benefits

  • Develop skills for specification of testing programs for GCL hydraulic and chemical compatibility properties
  • Develop skills for hydraulic and chemical compatibility design for GCL liner systems
  • Develop skills for assessment of field performance data for GCL liner systems

Assessment of Learning Outcomes

Students' achievement of the learning outcomes will be assessed via a short post-assessment (true-false, multiple choice and fill in the blank questions).

Intended Audience

  • Civil engineers
  • Geoenvironmental engineers
  • Geotechnical engineers
  • Geological engineers
  • Environmental engineers
  • Mining engineers
  • Hydrologists involved in landfill design, site remediation, mine waste containment, and low level radioactive waste containment
  • Landfill and containment system designers
  • Environmental regulators
  • Site owners

How to Earn your CEUs/PDHs and Receive Your Certificate of Completion

To receive your certificate of completion, you will need to complete a short on-line post-test and receive a passing score of 70% or higher within 1 year of purchasing the course.

How do I convert CEUs to PDHs?

1.0 CEU = 10 PDHs [Example: 0.1 CEU = 1 PDH]