Dante Grover stands in the boatyard of Al Grovers High and Dry Marina in Freeport on Wednesday, July 8, 2015. Al Grovers High and Dry Marina stopped using copper-laced paint on the bottom of its boats ...

Emissions from copper-based antifouling paints are a well-known environmental problem. As much as 40 percent of copper inputs to the Baltic Sea come from antifouling paints on ships and leisure boats.

After months of retooling, the Unified Port of San Diego is moving ahead with a plan to reduce the amount of copper that pollutes San Diego Bay per orders from regulators. The strategy would require ...