Corrosive groundwater, which has been linked to trace-metal leaching from plumbing materials in Europe and the United States , has been identified in the Coastal Plain of New Jersey. The corrosiveness of groundwater in the Kirkwood-Cohansey aquifer system in New Jersey has been estimated by calculating values for the Aggressive Index, using groundwater chemistry data. A contour map of Aggressive-Index values shows that groundwater is very corrosive in the vicinity of Ocean County, New Jersey. Areas with the least corrosive water are generally along the coast, whereas areas with the most corrosive water are farther inland. (USGS)