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Article Last Updated: 07/19/2006 |
Cold
War's killer gas on way to extinction
Burning of mustard agent starts; mercury a
hurdle
The U.S. Army on
Friday drained and incinerated the first of thousands of containers of deadly
mustard gas stored in Utah's west desert, beginning the last major phase of the
program to destroy much of the nation's aging chemical weapons.
The project will last six to
10 years and involve burning about 6,200 tons of liquid blister agent. The
disposal is complicated by the presence of an estimated 800 pounds of toxic
mercury.
The mustard gas is the last phase of the program to
destroy munitions stored at the Deseret Chemical Depot in Tooele County, which
at one time housed more of the nation's chemical weapons than any other storage
site. The destruction of the weapons by the Tooele Chemical Agency Disposal
Facility, a sophisticated burn project, began in 1996 and will help the United
States comply with the international Chemical Weapons Convention.
Workers at the Depot are sampling some of the 1-ton
containers holding the mustard agent to figure out which of them have low
concentrations of mercury. Workers will drain and incinerate those first, said
spokeswoman Alaine Southworth.
At the same time, workers will design and install
special sulfur-impregnated carbon filters that will scrub the mercury from the
exhaust when the higher-concentration containers are later disposed of,
Southworth said.
But a conservation organization questioned whether
depot officials really know the technology will work, and argued the Army
should instead employ a mustard gas disposal method used at Aberdeen Proving Ground
in Maryland.
Vanessa Pierce, director of Healthy Environment
Alliance of Utah, said the mustard agent could be neutralized with plain hot
water without releasing burn emissions.
"It still has to be treated as a hazardous waste,
but there is no risk of hazardous contaminants getting into our air," she
said.
Southworth acknowledged the technology but said
Aberdeen had only about a third as much gas to dispose of. Besides, the depot
in Tooele already has an incinerator that has safely disposed of 7,400 tons of
other nerve agents, she said.
The Army "feels both technologies are
equal," but it is more effective to incinerate here, she said.
According to the Council on Foreign Relations, mustard
gas (actually a liquid at room temperature) is one of the most potent chemical
weapons. First used during World War I, the gas causes severe blisters, and
external and internal bleeding, and strips the mucus membrane from airways. The
effects take hours to develop, which means victims can suffer tissue damage
before they even realize they need treatment. Mustard gas also attacks a cell's
DNA, increasing the risk of cancer and birth defects, and remains active in the
soil for weeks.
In 2004, the Army announced it would spend $50 million
to change the way it burns mustard agent to avoid mercury emissions.
Though it's believed there are 800 pounds of mercury
in the liquid chemical agent, Southworth estimated no more than one or two
pounds of the deadly neurotoxin would be released into the atmosphere during
incineration.
Pierce rejected the estimate.
"They don't know how much mercury is in all the
containers," she said. In any event, she added, ''mercury contamination is
a huge problem here. . . . It's better to take extra steps to ensure maximum
protection for workers and the public."
The highly toxic element occurs naturally in the
environment but also has been introduced through human activity, including
burning coal for electricity and processing gold ore.
Mercury evaporates easily. When snow and rain
redeposits it on land and in water bodies, certain chemical activity converts
it to its organic form, known as methylmercury.
Methylmercury, which accumulates in the bodies of
animals and humans, affects the human nervous system and is most harmful to
fetuses and young children because it can cause developmental and neurological
problems.
In February 2005, federal scientists reported finding
in the Great Salt Lake some of the highest levels of methlymercury ever
recorded in the United States. Though fish don't live in the lake, wildfowl
feed on its brine shrimp, algae and plants.
After the study, Utah environmental quality and health
agencies stepped up investigations into methylmercury contamination and issued
five mercury warnings concerning fish and wildfowl.
Poison cleanup
- The U.S. Army's Deseret Chemical Depot in Tooele
County, 60 miles from Salt Lake City, has begun incinerating 6,149 tons of
liquid mustard agent.
- Depot officials estimate the mustard gas also contains
about 800 pounds of elemental mercury. Emissions resulting from
incineration will be controlled by a $50 million filtration system.
- This is the largest chemical agent destruction
campaign the Army will conduct to meet requirements of the Chemical
Weapons Convention of 1997.
Destroying the deadly arsenal
- The Deseret Chemical Depot has been operating for
10 years, and has destroyed 7,409 tons of chemical agent and more than a
million munitions.
- The mustard gas incineration campaign is
scheduled to be completed by 2016 but may end as early as 2012.
- The Deseret Chemical Depot is one of eight Army
installations in the U.S. that currently stores chemical weapons. The
Tooele Chemical Agent Disposal Facility was built for the sole purpose of
destroying its chemical weapons stockpile.
- Operations began Aug. 22, 1996. The last of more
than 53,000 artillery projectiles filled with deadly VX nerve agent was
destroyed two years ago. Previously, the $1 billion incinerator at the
depot destroyed about 6,000 tons of GB agent, also known as sarin.
- Source: U.S. Army Chemical Materials Agency