U.S. seaports are the largest and most poorly regulated sources of urban pollution in the country, according to a report released by NRDC (Natural Resources Defense Council) and the Coalition for Clean Air. Harboring Pollution: The Dirty Truth about U.S. Ports grades the ten biggest seaports for their impact on air and water quality, land use, and nearby communities. The report finds that despite the availability of technology to cut pollution, major seaports are emitting ever-larger amounts of toxic diesel exhaust and other contaminants that damage public health, disrupt local communities and harm marine habitats. With cargo volume at some ports expected to triple in the next twenty years, the report urges quick action by port operators and policy-makers to implement cleaner practices.