TRAVERSE CITY, Mich. (AP) - The Environmental Protection Agency has issued new requirements for cleansing ballast water dumped from ships, which scientists believe has brought invasive species to U.S. waters that damage ecosystems and cost the economy billions of dollars.
A general permit released Thursday will apply to commercial vessels longer than 79 feet. It requires them to meet international standards for treating ballast water, which keeps ships stable in rough seas. The Coast Guard adopted similar requirements last year.
Ships could meet the standards by installing equipment that cleanses the water with chemicals or uses other methods to kill organisms.
The EPA says studies by its science advisory board endorsed the standards. But environmental groups say they're too weak to prevent more invasive species from slipping into the Great Lakes and coastal waterways.
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