Industry largely not responsible for oil pollution in North American oceans

By OGJ editors

WASHINGTON, DC, May 24 -- A vast majority of the oil that contaminates North American oceans does not come from tanker or pipeline accidents, according to a May 23 report from the National Academies' National Research Council.

About 85% of the 29 million gal of petroleum that enter North American ocean waters each year as a result of human activities comes from land-based runoff, polluted rivers, airplanes, and small boats and jet skis, while less than 8% comes from tanker or pipeline spills, the report said.

Oil exploration and extraction are responsible for only 3% of the petroleum that enters the sea, while another 47 million gal seep into the ocean naturally from the seafloor.

Consumer causes
Land runoff and recreational boating account for nearly three-quarters of the 25 million gal of petroleum released into the sea annually, NRC said. Other sources of oil from human activities include military and commercial jets that occasionally jettison excess fuel over the ocean and ships that release oil from their engines while in port or at sea.

Meanwhile, oil runoff from cars and trucks is increasing in coastal areas where the population is growing and roads and parking lots are expanding to accommodate it. Rivers polluted by oil in wastewater or the improper disposal of petroleum products are a significant source of oil in the sea as well.

In addition, older, two-stroke engines still found on many recreational boats and jet skis were purposely designed to discharge gasoline and oil. More than one half of the land-based oil contamination along the North American coastline occurs between Maine and Virginia, where there are dense seaside populations, many cities, several refineries, and high energy use, the report said. About 20% of the land-based petroleum entering North American coastal waters ends up in the Gulf of Mexico. The gulf also receives most of the oil and gas that is emitted by recreational boats and jet skis.

"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 since they represent most of the oil leaked by human activities," said James M. Coleman, chair of the committee that wrote the report and Boyd Professor, Coastal Studies Institute, Louisiana State University, Baton Rouge. "This doesn't mean we can ignore hazards from drilling and [oil] shipping, however. Although new safety standards and advances in technology reduced the amount of oil that spilled during extraction and transport in the last 2 decades, the potential is still there for a large spill, especially in regions with lax safety controls."

Government reactions
The study authors suggested the US Environmental Protection Agency should continue its efforts to phase-out older, inefficient, two-stroke engines that power many jet skis and other small watercraft. They also called for more coordination among federal, state, and local environmental officials to monitor oil pollution sources in order to reduce existing run-off problems. The committee's calculations of how much petroleum is added to the sea each year were based on data from a variety of sources, including new data that did not exist in a 1985 report, NRC said. NRC authors said the new data are encouraging but regulators still must be vigilant to ensure the ocean's fragile ecosystem is protected.

The US Coast Guard and US Maritime Administration should work with ship owners domestically and internationally through the International Maritime Organization to expand and enforce shipping standards that already have contributed to a decline in oil spills and operational discharges, the report stressed.

Annually, about 2.7 million gal of petroleum spill into North American waters while being transported to market. However, the report cautions that large tanker spills are still possible, especially in areas without stringent safety procedures and inspections. It says the US Department of Transportation and EPA also should continue work with state environmental agencies and industry to assess and minimize the potential for a significant spill from pipelines and other coastal facilities.
Industry's role cannot be completely discounted, NRC said.

The exploration and extraction of oil and natural gas introduces 880,000 gal of petroleum to North American waters each year. These leaks are concentrated where oil-drilling rigs are at work in the Gulf of Mexico and off southern California, northern Alaska, and eastern Canada. The amount of petroleum released during extraction has dropped significantly, but the threat of a spill cannot be ignored, the report said. To that end, the US Minerals Management Service should continue to work with state environmental agencies and industry to promote extraction techniques that minimize accidental or intentional releases of petroleum, according to study authors.

The report also says federal ocean-management agencies should try to develop more accurate techniques for estimating the amount of oil that seeps into the ocean from geologic formations beneath the seafloor. This would help researchers distinguish the effects of petroleum released by natural processes vs. human activities and study how marine life responds to the introduction of oil.

Vigilance still required
The amount of petroleum released into North American and global waters is less than previously thought, the report said. At the same time, however, new studies show that the environmental effects of a major oil spill are longer-lasting than once thought and that even small amounts of petroleum can seriously damage marine life and ecosystems."Oil slicks visible from the air and birds painted black by oil get the most public attention, but it is consumers of oil—not the ships that transport it—who are responsible for most of what finds its way into the ocean," the report said.