Prioritization of Aquifers for Ambient Groundwater Monitoring

Ambient groundwater monitoring programs have been developed by more than half of the states in the United States in order to determine baseline groundwater quality and monitor long-term water quality trends.  States have focused their resources in many cases by prioritizing certain basins (groundwater or watershed), major aquifers, or sensitive areas.  In 2006 Wyoming developed an aquifer prioritization mapping approach specifically designed to target ambient groundwater monitoring efforts to ‘priority’ areas where shallow (<500 feet below surface) groundwater is used for drinking water supplies, where those groundwater resources may be considered ‘sensitive’ to pollution, and where those resources are susceptible to point- and non-point source pollution.  A sparsely populated state, Wyoming has used this approach to focus its monitoring resources to those areas where groundwater is used, in part, as sources for drinking water and may be considered vulnerable.