Forensic Chemistry Investigation of Nitrate Contamination and Sources in Groundwater in the Southwestern United States(ABSTRACT)

摘要

At a site in the southwestern United States, nitrate contamination of groundwater has been a continuing problem. Several potential sources exist, including sanitary sewer lines with a history of major breaks, sewage lagoons, industrial operations known to have released nitric acid, and off-site nitrate sources migrating in surface drainages to the site. Nitrate concentrations in groundwater exhibited an increasing trend in concentration prior to this investigation, with concentrations in some wells exceeding the federal MCL. Nitrate contamination threatened potable water wells, forcing installation of groundwater extraction wells to prevent further migration of the nitrate plume. A forensic chemistry investigation was conducted to identify sources, release mechanisms, and transport pathways of nitrate.