Dear EarthTalk: I haven't heard much of late about big oil spills like the infamous Exxon Valdez. Has the industry cleaned up its act, or do the media just not report them?

Dear EarthTalk: I haven't heard much of late about big oil spills like the infamous Exxon Valdez. Has the industry cleaned up its act, or do the media just not report them?

--Olivia G., via e-mail

In the wake of 1989's massive Exxon Valdez oil spill in Alaska's Prince William Sound, when 11 million gallons of oil befouled some 1,300 miles of formerly pristine and wildlife-rich coastline, much has been done to prevent future spills of such magnitude.

For starters, Congress quickly passed the 1990 Oil Pollution Act which overhauled shipping regulations, imposed new liability on the industry, required detailed response plans and added extra safeguards for shipping in Prince William Sound itself. Under the terms of the law, companies cannot ship oil in any U.S. waters unless they prove they have response and clean-up plans in place and have the manpower and equipment on hand to respond quickly and effectively in the case of another disaster.

Also, the law mandates that, by 2015, all tankers in U.S. waters must be equipped with double hulls. The Exxon Valdez had only one hull when it ran aground on Bligh Reef and poured its oil into Prince William Sound, the southern end of the oil pipeline that originates 800 miles to the north at Prudhoe Bay. By comparison, a 900-foot double-hulled tanker carrying nearly 40 million gallons of crude oil did not leak when it crashed into submerged debris near Galveston, Texas in March 2009.

According to the U.S. Coast Guard, average annual oil spill totals have dropped dramatically since new regulations took effect in 1990. Between 1973 and 1990, an average of 11.8 million gallons of oil spilled each year in American waters. Since then, the average has dropped to just 1.5 million gallons, with the biggest spill (not including those resulting from Hurricane Katrina in 2005) less than 600,000 gallons

Despite these improvements, critics say the industry still has more work to do. While protections have been beefed up in Prince William Sound, other major American ports still lack extra precautions such as escort tugboats and double engines and rudders on big ships to help steer them to safety when in trouble.

Another area that the 1990 law doesn't cover is container ships that don't transport oil as their cargo but which carry a large amount, anyway, for their own fuel for the considerable distances they travel. Such ships could also cause a major spill (anything more than 100,000 gallons, by Coast Guard standards). Yet another concern is the great number of smaller oil spills that occur every day at industrial locations (including but not limited to oil refining and storage facilities) and even in our own driveways. These will continue to add up to a heavy toll on our environment, even if another oil tanker never spills at sea again.

And while the total number and volume of oil spills is down dramatically from bygone days, the trend of late warrants concern. The National Oceanic and Atmospheric Administration's (NOAA's) Office of Response and Restoration reports that oil spills in U.S. waters have risen again over the past decade, with 134 incidents in 2008 alone. Green leaders worry that if Bush administration plans to expand offshore oil drilling are not overturned by President Obama, oil spills in U.S. waters could remain a sad fact of life.

CONTACTS: NOAA Office of Response and Restoration, www.response.restoration.noaa.gov; U.S. EPA Oil Pollution Act Overview, www.epa.gov/OEM/content/lawsregs/opaover.htm.

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