ABSTRACT
Webster’s New Collegiate Dictionary defines the verb “contaminate” as a process by which a material is made “inferior or impure by admixture” or made “unfit for use by the introduction of unwholesome or undesirable elements”. While both of these definitions 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 identification of groundwater contaminants and their effects will require knowledge of pre-existing or background conditions.
