ABSTRACT
Webster’s New Collegiate Dictionary denes the verb “contaminate” as a process by which a material is made “inferior or impure by admixture” or made “unt for use by the introduction of unwholesome or undesirable elements.” While both of these denitions are accurate, they do not fully represent the connotation with which the word is used. For purposes of this chapter, the term “contaminant” will generally refer to an undesirable constituent that is introduced directly or indirectly as a result of human activity. Furthermore, the identication of groundwater contaminants and their eects will require knowledge of preexisting or background conditions.
