GCLs and hydraulic equivalence

By Timothy D. Stark

Q: Are GCLs hydraulically equivalent to a compacted low permeability soil liner?

A: A good, but difficult, question. GCLs are hydraulically equivalent to low permeability soil liner in terms of advective flow. However, GCLs are not hydraulically equivalent to low permeability soil liner in terms of diffusive flow unless a natural attenuation layer underlying the GCL is considered in the diffusion analysis.

Tim Stark is a professor in the Department of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign.