Researchers have uncovered previously hidden sources of ocean pollution along more than 20% of America's coastlines. it offers the first-ever map of underground drainage systems connecting groundwater and seawater, and also pinpoints sites where drinking water is most vulnerable to saltwater

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Researchers have uncovered previously hidden sources of ocean pollution along more than 20% of America's coastlines. it offers the first-ever map of underground drainage systems connecting groundwater and seawater, and also pinpoints sites where drinking water is most vulnerable to saltwater