The hazardous waste management business has steadily increased since the mid-1970s as public concern led to a vast range of new and stringent environmental regulations. With regard to groundwater and soil, a substantial amount of time and expense has been devoted to studying impacted sites, with much of the effort dedicated to litigation to determine the financially responsible parties. However, the focus has switched in recent years from litigation and site assessment to remediation. Site restoration usually proceeds through several phases and requires a concerted, multidisciplinary effort. Thus, remediation professionals come from a variety of technical and educational backgrounds, including geology, hydrology, chemistry, microbiology, meteorology, toxicology and epidemiology, as well as chemical, mechanical, electrical, industrial, civil, and environmental engineering. Because of differences in the formal education and training of these professionals, their ability to perform or review remediation design calculations varies considerably. For some, performing accurate design calculations for site remediation can become a seemingly insurmountable task.