Permeable Reactive Barriers: Cost-Effective and Sustainable Remediation of Groundwater - Permeable Reactive Barrier: Sustainable Groundwater Remediation - page 1

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Permeable Reactive Barriers: Cost-Effective
and Sustainable Remediation of
Groundwat er
Ravi Naidu, Dawit N. Bekele, and Volker Birke
CONTENTS
1.1 Introduction .................................................................................................... 1
1.2 Groundwater Contamination ....................................................................... 2
1.2.1 Groundwater Contamination Fate and Transport ........................ 4
1.3 Groundwater Remediation ........................................................................... 7
1.4 PRBs: Emerging Technology for Groundwater Remediation ................ 13
1.4.1 Potential Problems Associated with the Long-Term
Performance of PRBs ....................................................................... 16
1.5 Conclusion .................................................................................................... 19
References ............................................................................................................... 19
1.1 Introduction
Contaminated sites represent a major challenge for the long-term sustain-
ability of the environment. In addition to their potential adverse impacts on
human health, surface and groundwater quality, and ecological processes,
they also represent a lost economic opportunity. Sources of contaminants
include those arising from anthropogenic activities such as industrial and
agricultural practices, mining activities, accidental spillages, and so on
(Barzi et al., 1996; Naidu, 1996), and natural geogenic processes (Naidu et al.,
2006), with the latter largely associated with metals and metalloids such as
arsenic, lead, cadmium, and mercury. Irrespective of the source of contami-
nants, they will interact with soil colloidal particles and moisture in the near-
surface leachable zone. They can, therefore, be dissolved/solubilized into
water infiltrating through any unsaturated zone present in the soil profile.
They can penetrate below the water table and subsequently migrate laterally
in flowing groundwater and transported off-site, thus posing a serious risk
to groundwater quality.
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