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term contamination sources and release acutely toxic and highly persistent compounds (e.g.,
benzene, toluene, naphthalene). Serious health and ecological concerns have been raised over
the adverse effects of the release of these compounds into groundwater. Regulatory bodies
(Health Canada and USEPA) have established specific guidelines on the maximum
concentration of these contaminants that can exist in natural systems. Frequent and serious
impacts on the subsurface and strict cleanup regulations have resulted in the inclusion of
PHC contaminated sites on the NPL list and have encouraged and promoted remedial action.
The relatively high solubility as compared to maximum concentration limits (MCLs) of the
PHC compounds, low retardation and relatively low biodegradation leads to increased plume
lengths and higher impact in receptors. PHC contamination continues to persist until the
source zone is removed, quarantined, attenuated or treated in place (Lundegaard and
Johnson, 2007). Bench-scale studies have demonstrated the ability of using activated
persulfate to destroy BTEX compounds (Crimi and Taylor, 2007, Liang et al., 2009).
Unfortunately, these studies either investigated the treatment of an individual compound or
by simulating a mixture of a few constituent compounds. Lab-scale treatability studies, while
illustrative, are not representative and therefore not sufficient for evaluation of persulfate
performance at pilot- or field-scale. The current empirical assessment of these interactions in
a field-scale groundwater system containing persulfate, petroleum hydrocarbons, and aquifer
materials is very limited and necessitates a comprehensive analysis.
1.5. RESEARCH OBJECTIVES
To improve our understanding of the macro-level chemical interactions between persulfate
and aquifer material constituents and to enhance the knowledge of ISCO remediation specific
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