Professional Project Defense: Christina Keleher

Nitrate Contaminated Groundwater in Albuquerque's South Valley: Is Monitored Natural Attenuation an Appropriate Strategy?

Date: Wednesday, November 5, 2008
Time: 10:00 AM
Location: Economics Bldg. Room 1052

Abstract

Nitrate contaminated groundwater in the South Valley of Albuquerque has been documented since the early 1960's. Over the past four decades, nitrate concentrations have declined, but are still significantly greater than the groundwater standard of 10 mg/L. Although the nitrate contaminated water no longer presents a human health threat to the residents of Mountain View, all groundwater in New Mexico that contains less than 10,000 ppm total dissolved solids and is subject to New Mexico groundwater standards and should be considered a potential future drinking water source. It may be argued that the nitrate plume is relatively stable and therefore monitored natural attenuation is a more appropriate and less costly alternative than remediation of the nitrate. The New Mexico Environment Department uses a process of risk based decision making to evaluate the risks to human health and the environment posed by leaking petroleum storage tanks. In addition to a comprehensive review of the history of the nitrate contaminated groundwater in Mountain View, and a review of government regulations pertaining to nitrate contamination of groundwater in NM, this professional project applied a modified risk assessment to determine whether the nitrate plume poses enough risk to future development to justify remediation. The risk assessment factored in receptors, pathways of exposure, fate and transport parameters as well as estimated characteristics of the nitrate plume, among other things. Taking into account the results of the risk assessment and current New Mexico regulations, the most prudent alternative, considering human health, is to remediate the contamination.