Oil Pollution Comes In Dribs And Drabs

It's not just leaking oil tankers that are responsible for oil pollution in U.S. coastal waters. Blame the cities, reports CBS News Correspondent Peter King.

More than half of the 29 million gallons that end up in U.S. coastal waters comes from human activities: street runoff, industrial waste, municipal wastewater and wastewater from refineries.

In addition, 1.6 million gallons of the pollution comes from recreational vessels, where two-stroke engines that mix oil and gas are often used in personal watercraft and as outboard engines.

"Small dribs and drabs add up to a very large amount," said Dr. Dan Walker of the National Academy of Sciences, adding that the east coast from Maine to Virginia contributes more than half the land-based coastal pollution.

"Obviously, there's a great concentration of cars, there's a greater concentration of the use of petroleum and you have a lot of paved surfaces," he said.

"Oil spills can have long-lasting and devastating effects on the ocean environment, but we need to know more about damage caused by petroleum from land-based sources and small watercraft," commented James M. Coleman of Louisiana State University, chairman of the committee that prepared the study.

The report urged that federal officials work with state agencies to better monitor oil discharges and suggested that the Environmental Protection Agency work to phase out two-stroke engines.

Another significant source of pollution was "atmospheric deposition," that is oil that is deposited on the ocean surface as a result of emissions into the air from motor vehicles, power generating facilities, industrial plants and similar sources. That was estimated to total 6.1 million gallons.

The higher the concentration of people, the higher the pollution, said Walker.

"You've got a lot of oil that's being used, being handled, being spilled occasionally in small amounts, and a lot of surface area tends to create a situation where runoff has fairly high concentrations of petroleum in it," he said.

Spills from tankers accounted for 1.5 million gallons of pollution and 551,000 gallons came from pipeline spills, the report found.

"This doesn't mean we can ignore hazards from drilling and shipping, however. Although new safety standards and advances in technology reduced the amount of oil that spilled during extraction and transport during the last two decades, the potential is still there for a large spill, especially in regions with lax safety controls," added Coleman.

The single largest source of oil in the oceans bordering North America is natural seepage from undersea oil sources, releasing an estimated 46.4 million gallons annually.

Worldwide, vessel and pipeline spills were blamed for release of 32.5 million gallons annually into the oceans. Runoff adds another 41 million gallons and international operational discharges from vessels, such as from cargo washing, was listed as producing an added 78 million gallons of pollution. Such discharges are illegal in North American waters.

The National Research Council is an arm of the National Academy of Sciences, a private organization chartered by Congress to advise the government on scientific matters.