What Is Monitored Natural
Attenuation?
Natural attenuation relies on natural processes
to decrease or “attenuate” concentrations of
contaminants in soil and groundwater. Scientists
monitor these conditions to make sure natural
attenuation is working. Monitoring typically involves
collecting soil and groundwater samples to analyze
them for the presence of contaminants and other site
characteristics. The entire process is called “monitored
natural attenuation” or “MNA.” Natural attenuation
occurs at most contaminated sites. However, the
right conditions must exist underground to clean sites
properly and quickly enough. Regular monitoring must
be conducted to ensure that MNA continues to work.