To reduce hazardous winter driving conditions, highway departments turn to salt de-icers. Does road salt affect groundwater? If so, is there a lasting impact that can be measured? The Delaware Geological Survey is taking an in-depth look at groundwater quality. Rachel McQuiggan, a researcher at the University of Delaware, is monitoring storm water and groundwater at infiltration basins — large, shallow roadside pools that allow water to infiltrate the groundwater.