Although leaking oil tankers may produce dramatic photos, a new study says the vast majority of the human-related petroleum released into U.S. coastal waters comes from consumers, not leaking ships, reports Associated Press writer Randolph E. Schmid.
The National Research Council reported Thursday that about 29 million gallons of oil enters the oceans around North America each year as a result of human activities. Of that, the largest share, 15.6 million gallons, comes from rivers and runoff, largely from such things as 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 often are used in personal watercraft and as outboard engines.
"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 heavily populated coastline from Maine to Virginia accounts for more than half of the land-based oil pollution in U.S. waters, with another 20 percent in the Gulf of Mexico.
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.
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 seeps 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.