Two Decades of Application of Permeable Reactive Barriers to Groundwater Remediation - Permeable Reactive Barrier: Sustainable Groundwater Remediation - page 37

2.5 Conclusion
The ability to use PRBs to destroy or immobilize dissolved chemical con-
stituents is dependent on many issues, including cost and constructability,
but notably, effective and complete site characterization. Advances in PRB
development, notably in the use of natural materials and the advanced use
of traditional treatment materials (such as ZVI), will continue to develop
and provide practitioners with a bevy of new options intended to be highly
effective, and also highly cost efficient. Expected research and assessment
into the effective longevity of PRB materials used within an application will
likely be a primary focus over the next several years.
Because the PRB is a passive technology, which is not easily adjusted once
installed, an accurate conceptual model must be developed and the most
important data gaps must be filled before a PRB can take on a final design. If
the PRB is designed based on incomplete or inaccurate site information, fail-
ure or unintended performance may result. The PRB may not be the correct
remedy to select for many contaminant remediation schemes; however, the
several decade experience that our profession has with the PRB technology
opens up many more potential opportunities for reducing cost, impact, and
secondary treatment issues that characterize the difficulty in mitigating radio-
active plumes. Technologies for implementing PRBs will continue to improve
and develop (such as injection and deep-well PRB installation); the benefits of
not having to pump groundwater nor supply ongoing energy for treatment
will be the primary drivers for the development of new technologies.
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