PITTSBURGH (AP) — In the Colorado mountains, a spike in
air pollution has been linked to a boom in oil and gas drilling. A
thousand miles away on the plains of north Texas, there's a drilling
boom, too, but some air pollution levels have declined. Opponents of
drilling point to Colorado and say it's dangerous. Companies point to
Texas and say drilling is safe.
The answer appears to be that
drilling can be safe or it can be dangerous. Industry practices,
enforcement, geography and even snow cover can minimize or magnify air
pollution problems.
"It's like a vehicle. Some cars drip oil,"
said Russell Schnell, deputy director of the federal Earth System
Research Laboratory in Boulder, Colo. "You have wells that are
absolutely tight. And you have other places where a valve gives out, and
you have huge leaks."
The good news, nearly all sides agree, is
that the technology exists to control methane gas leaks and other air
pollution associated with drilling. The bad news is that the industry is
booming so rapidly that some companies and some regulators can't seem
to get ahead of the problems, which could ultimately cost billions of
dollars to remedy.
The worries about what drilling does to the air
are both global and local, with scientists concerned about the effects
on climate change as well as the possible health consequences from
breathing smog, soot and other pollutants.
Hydraulic fracturing,
or fracking, has made it possible to tap into deep reserves of oil and
gas but has also raised concerns about pollution. The industry and many
federal and state officials say the practice is safe when done properly,
but environmental groups and some scientists say there hasn't been
enough research.
Some environmentalists say if leaks and pollution
can be minimized, the boom has benefits, since gas burns much cleaner
than coal, emitting half the carbon dioxide.
Al Gore told The
Associated Press that it's "not irresponsible" to look at gas as a
short-term substitute for coal-fired electricity. But Gore added that
the main component of gas, methane, is a more potent heat-trapping
greenhouse gas than CO2. That means that if large quantities leak, the
advantage over coal disappears, the former vice president said.
In
Colorado, the National Oceanic and Atmospheric Administration estimated
that 4 percent of methane was leaking from wells, far more than
previously estimated, and that people who live near production areas may
be exposed to worrisome levels of benzene and other toxic compounds
present in oil and gas.
Across the industry, the technology for
stopping leaks can be as simple as fixing seals and gaskets, or it can
involve hundreds of millions of dollars of new construction.
"I think it's totally fixable," Schnell said. "At least the bigger companies, they are really on top of this."
Gore
added that when companies capture leaking methane, they end up with
more to sell. "So there's an economic incentive to capture it and stop
the leaking," he said.
Another major source of worry is the
industry's practice of burning off, or flaring, natural gas that comes
out of the ground as a byproduct of oil drilling. Over the past five
years, the U.S. has increased the amount of flared and wasted gas more
than any other nation, though Russia still burns off far more than any
other country.
In some places, energy companies haven't invested
in the infrastructure needed to capture and process the gas because the
oil is more valuable.
In the Bakken Shale oil fields of North
Dakota, for example, about 30 percent of the natural gas is flared off
because there aren't enough pipelines yet to carry it away. The amount
of gas wasted in the state is estimated at up to $100 million a year.
And officials in North Dakota said last month that the situation there
might not be completely solved until the end of the decade.
NOAA
scientists also say natural gas production has contributed to unusual
wintertime smog in the West, particularly in regions surrounded by
mountains, and especially in snowy areas.
Ozone, the main
component in smog, typically forms when sunlight "cooks" a low-lying
stew of chemicals such as benzene and engine exhaust. Normally, the
process doesn't happen in cold weather.
But NOAA researchers found
that when there's heavy snowfall, the sun passes through the stew, then
bounces off the snow and heats it again on the way back up. In some
cases, smog in remote areas has spiked to levels higher than those in
New York or Los Angeles.
In open regions that are more exposed to
wind, the ozone vanishes, sometimes within hours or a day. But in Utah
basins it can linger for weeks, Schnell said.
Evidence that gas
drilling air pollution can be managed — but that more work may still
need to be done — comes from north Texas, where the shale gas boom began
around Fort Worth about 10 years ago.
Mike Honeycutt, director of
toxicology for the Texas Commission on Environmental Quality, said that
in the early years of the boom, people complained about excessive
pollution. Regulators started using special hand-held cameras to
pinpoint pollution sources and found some sites with high levels of
benzene and other volatile organic compounds.
"It was a
maintenance issue. They were in such a hurry, and they were drilling so
fast, they were not being as vigilant as they should have been,"
Honeycutt said. "So we passed new rules that made them take more
notice."
Honeycutt said the cameras, which cost about $100,000
each, have revolutionized the way inspectors monitor sites. Texas has
also installed nine 24-hour air monitoring stations in the drilling
region around Fort Worth, and more are on the way. Now, he said, even as
drilling has increased, summer ozone levels have declined.
In
1997 there were only a few hundred shale gas wells in the Fort Worth
area and the summertime ozone level hit 104 parts per billion, far above
the national standard then of 85. By 2012 the number of wells had risen
to about 16,000, but preliminary results show the ozone level was 87
last summer.
There's still room for improvement, Honeycutt said,
but the trend is clear, since the monitoring is no longer showing
worrisome levels of benzene, either.
The Environmental Protection
Agency isn't completely convinced. This year the federal agency cited
Wise County in north Texas, a heavy gas drilling area, for violating
ozone standards. Industry groups and the state have argued that the
finding was based on faulty science.
So far, NOAA scientists say they haven't found signs that gas or oil drilling is contributing to a global rise in methane.
"Not
the mid-latitudes where the drilling is being done, which is
interesting," said James Butler, head of global monitoring for NOAA.
The
EPA has passed new rules on oil and gas emissions that are scheduled to
go into effect in 2015, and in 2012 it reached legal settlements that
will require companies to spend more than $14 million on pollution
controls in Utah and Wyoming. Colorado, Texas and other states have
passed more stringent rules, too.
Carlton Carroll, a spokesman for
the American Petroleum Institute, a lobbying group for the oil and gas
industry, pointed out that many companies started developing the
equipment to limit methane and other pollution before the EPA rule.
"API
is not opposed to controls on oil and gas operations so long as the
controls are cost-effective, allow sufficient lead time and can be
implemented safely," Carroll said in an email, adding that the industry
has requested some technical clarifications to the rule and is working
with EPA on those.
Prasad Kasibhatla, a professor of environmental
chemistry at Duke University, said that controlling gas drilling
pollution is "technically solvable" but requires close attention by
regulators.
"One has to demonstrate that it is solved, and monitored," he said.