Reactive spreading reaction limited

Groundwater remediation is the often expensive process of restoring an aquifer after it has been contaminated, or at least limiting the ability of contaminants there to spread. In this chapter, we consider the widespread problem of the contamination of groundwater flows with heavy metals. We use reactive transport modeling to look at the reactions that occur as contaminated water enters a pristine aquifer, and those accompanying remediation efforts. 

In other substitution reactions, such as halogenation, the reactivity determinations are necessarily based on the quantitative analysis of product mixtures. The results can often be dubious, especially if individual site reactivities show a wide spread. Protodedeuteration is not subject to this limitation because the reactivities of individual positions are determined in separate experiments. 

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