By Kent Garber
U.S. News reports the growth and environmental impact of marine dead zones: large, oxygen-depleted swaths of water that form each summer off the U.S. coast because of fertilizer runoff and other pollutants.
Among other concerns, scientists have warned that efforts to meet recently adopted U.S. energy policies will likely stall efforts to reduce the size of dead zones, since the extra fertilizer needed to satisfy the demand for corn for corn-based ethanol will send more nitrogen and phosphorous into waterways.
Now, new figures point to the immediacy of the problem.
In a forecast released this week, a team of Louisiana scientists predicts that the Gulf of Mexico dead zone will cover more than 10,000 square miles this summer, a swath nearly 20 percent larger than the record-setting dead zone of 2002 and more than 50 percent larger than the annual average since 1990.
Behind the growth, they say, is a sizable increase in the nitrogen load at the mouth of the Mississippi River and in the Gulf. One reason: U.S. farmers, encouraged by ethanol mandates and higher commodity prices, have expanded corn plantings and driven the acreage of other crops to record levels. Farmers are using more fertilizer, which contains nitrogen and phosphorous. These chemicals, when not used by crops, often find their way from farmland into water. Corn, because of its shallow roots, tends to be quite "leaky."
In May, the team of scientists, which includes researchers from Louisiana State University and the Louisiana Universities Marine Consortium, found that nitrogen loading in the Gulf was 37 percent higher this year than in May 2007. The level was the highest since researchers began taking measurements in 1970.
The predicted size of the dead zone--roughly that of the state of Massachusetts--has researchers particularly worried.
Although the dead zone has gradually expanded over time, it has remained confined to relatively shallow water and has yet to seep over the ocean shelf and into deeper water. But that streak could be in peril. "The shelf only has so much room," R. Eugene Turner, the Louisiana State professor who led the forecasting team, told U.S. News. "It is getting saturated."
This year, researchers began finding low-oxygen (or hypoxic) regions around coastal Louisiana in March. Since then, as the runoff from spring crop plantings has made its way south down the Mississippi, these regions have been growing, as accumulating nitrogen and phosphorous fuel the growth of algae that, upon decomposing, depletes the water of oxygen. The cycle this year has been aided by more water flowing into the Gulf from the Mississippi because of rainfall and year-to-year climate changes.
By Erica Werner
A House committee chairman on Friday threatened to hold the head of the EPA and a White House budget official in contempt of Congress for not handing over documents about new smog requirements and a decision blocking California greenhouse gas limits.
Democratic Rep. Henry Waxman of California, chairman of the House Government Reform and Oversight Committee, said he'd hold a vote in his committee next week on a contempt resolution, if he doesn't get the information he wants.
He made the threat in letters to EPA Administrator Stephen Johnson and Susan Dudley, administrator for information and regulatory affairs at the White House Office of Management and Budget.
Waxman and others have complained about evidence that the White House intervened with the Environmental Protection Agency to produce more industry-friendly outcomes on both the smog and greenhouse gas issues.
Waxman has issued a series of subpoenas to learn more, but weeks have passed and neither EPA nor the Office of Management and Budget has fully complied. Waxman said Friday he'd waited long enough.
"I regret that your failure to produce responsive documents has created this impasse, but Congress has a constitutional duty to conduct oversight of the executive branch," he wrote to both officials.
"Therefore, unless the documents are provided to the committee or a valid assertion of executive privilege is made, the committee will meet on June 20 to consider a resolution holding you in contempt," Waxman wrote.
EPA spokesman Jonathan Shradar said his agency has turned over tens of thousands of documents to Waxman "and there has been no wrongdoing uncovered."
"The committee seems to be on a political hunt that will leave them wanting yet again," Shradar said in a statement.
OMB spokeswoman Jane K. Lee called Waxman's move "unfortunate" and said the office that Dudley heads "has gone to great lengths to cooperate with the committee, providing voluminous documents on an expedited basis (more than 7,500 pages)."
Johnson has consistently maintained that he was the one who made the final decisions on the smog rule and the California greenhouse gas waiver.
The EPA in March issued tougher health standards for ozone, commonly known as smog, but they weren't as tough as recommended by an EPA science advisory board and many health experts.
The EPA also did not go as far as the science panel had recommended in setting a separate standard to protect the environment from smog. EPA and White House officials have acknowledged that a tougher standard had been opposed by the Office of Management and Budget and the issue was settled after President Bush intervened directly on behalf of the White House staff only hours before the rule was announced.
On the California greenhouse gas issue, Waxman's committee staff produced a report last month concluding from interviews with high-level EPA officials that Johnson initially supported giving California full or partial permission to limit tailpipe emissions — but reversed himself after hearing from the White House.
More than a dozen other states were also blocked from implementing the tailpipe emission limits after Johnson rejected California's request for a required federal waiver in December.
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