Sites contaminated with metals and radionuclides present unique challenges to the development of effective remedial alternatives that also provide long-term protection to human health and the environment. The high costs of ongoing conventional treatment, total removal, and/or management combined with the scale of potential health and environmental risks make it important to evaluate attenuation-based remedial alternatives. Sites that have been identified as having metal and/or radionuclide contamination include federal facilities, industrial (e.g., mines) sites, disposal sites, and transportation corridors. Common metals include arsenic, cadmium, chromium, lead, nickel, copper, and selenium. For radioactive hazardous substances, uranium, radium, strontium, technetium, tritium, and thorium are the most common contaminants of concern. The attenuation processes affect most metals and radionuclides by changing their valence state, which in turn affects their solubility and therefore mobility. When properly employed, Monitored Natural Attenuation (MNA) is an effective knowledge-based remedy where a thorough engineering analysis informs the understanding, monitoring, predicting, and documenting of natural processes. In order to properly employ this remedy, there needs to be a strong scientific basis supported by appropriate research and site-specific monitoring implemented in accordance with quality systems.
This training and the associated ITRC Technical and Regulatory Guidance document, A Decision Framework for Applying Monitored Natural Attenuation Processes to Metals and Radionuclides in Groundwater (APMR-1, 2010), is intended for anyone involved with evaluating, investigating, remediating or managing a site that involves metal and radionuclide contaminants in groundwater. This training and document provides:
- Introduction to key attenuation processes for metals and radionuclides
- Information on incorporating MNA into remedial alternatives for metals/rads
- Overview of the decision framework on MNA for metals and radionuclides in groundwater within the larger evaluation framework of a contaminated site