Charleston is the capital of West Virginia and its largest
city, although its population barely exceeds 50,000. It's a safe bet that nearly all 50,000 residents were in
various states of annoyance ranging from ticked to furious as they learned last
Friday, January 10, that the water supply for not only their city, but nine
surrounding counties as well, was unsuitable for anything except flushing
toilets. How come? A little-known industrial chemical used
for washing coal had leaked into the Elk River just above the main intake pipe
for the city's water supply.
Exactly how this happened, and whether it's a cause for serious concern
or only a transient inconvenience, are questions that we don't have answers to
yet. But the incident has already
revealed problems ranging from inadequate protection from leaking storage tanks
to inadequate knowledge about obscure chemicals.
Large tanks of stuff have been rupturing and spreading death
and destruction ever since engineers learned how to build large tanks. Perhaps the most famous disaster involving
an industrial storage tank rupture was the Boston Molasses Disaster of
1919. A two-million-gallon tank
filled with molasses for the manufacture of alcohol used in munitions gave way,
and sent a 25-foot-high wave of goo at speeds up to 35 miles an hour racing
through downtown Boston, killing 21 and injuring 150. It was such incidents that inspired the practice of
surrounding large tanks with containment dikes, which can be seen at most tank
farms around the country. The idea
of a containment dike is that if the tank lets go, the contents will at least
be slowed down by the dike, if not contained altogether. I am not familiar enough with the
regulations governing tank construction to know whether containment dikes have
to be sealed with impervious layers of rubber or tar, a precaution often taken
in landfill construction. But it
is obvious that the containment dike at Freedom Industries failed to stop about
5,000 gallons of 4-methylcyclohexane methanol (MCHM) from getting into the Elk
River and thus into the West Virginia American Water Company's pipes. Once that happened, the whole water system
had to be flushed, which could take days.
In the meantime, you will have trouble finding bottled water in
Charleston, because it vanished from the shelves as soon as the water company
announced the problem.
The chemical, which reportedly smells like licorice (its
strong smell was how the leak was originally found), is not known to be
hazardous, but on the other hand, no extensive toxicity tests have apparently
been made on it either.
Determining toxicity to humans in a way that would satisfy the U. S. Food
and Drug Administration is a costly business, and so for chemicals that will
probably not end up in food or otherwise in close contact with humans, chemical
companies don't bother to investigate it unless there are obvious hazards. Every chemical sold has to have a
Material Safety Data Sheet (MSDS), but the information on these sheets comes
from various places and is not up to the FDA standard. Because washing coal is clearly not a
consumer-type application, nobody has done a study on whether the licorice-smelling
compound in question can harm humans.
Probably the best data we can get will come from future demographic
studies in the area served by the Charleston water supply utility. In the meantime, it is worth
considering whether the old Toxic Substances Control Act of 1976 should be
updated. Right now, all a chemical
company has to do to legally sell a new chemical is to notify the U. S.
Environmental Protection Agency of the chemical's composition. The EPA resorts to computer modeling to
guess whether the new compound is hazardous, and either lets it go or regulates
it, depending on the result. No
actual safety tests are required.
Certainly there is food for legislative thought here, but Congress seems
to have other things on its collective mind recently.
The West Virginia American Water Company did the right thing
in promptly notifying its customers not to use the contaminated water. Similar precautions are called for on a
smaller scale quite frequently when supply-line breaks result in contamination
with ground water. In those cases,
residents can safely use water for drinking purposes after boiling it, but
boiling wouldn't get rid of MCHM, so bottled water is the only alternative for
a few days.
Another lesson to be learned is how a system with no backup
water source can be especially vulnerable. Apparently the water utility had only one set of intake
pipes, and no wells or other sources.
At the least, this situation would call for heightened scrutiny of any
chemical plants a few miles upriver from the intake pipes, with perhaps added
safety precautions above and beyond the usual ones required for plants that
could leak into the river just above the intake site.
Monday-morning quarterbacking is easy, and I'm not having to
go out and hunt down the last gallon of bottled water on the shelves until the
water coming out of my kitchen faucet no longer smells like licorice. (I predict a steep decline in licorice
sales in West Virginia, by the way.)
But given the unfortunate circumstances, the authorities in West
Virginia's capital appear to have handled the situation reasonably well, and
hopefully there won't be any consequences worse than the inconvenience of using
bottled water for a while.
Sources: I referred to an article by Deborah
Blum at http://www.wired.com/wiredscience/2014/01/chemical-guesswork-in-west-virginia/
and a New York Times
article by Trip Gabriel on the accident at http://www.nytimes.com/2014/01/11/us/west-virginia-chemical-spill.html. I also used Wikipedia articles on
Charleston, West Virginia, and the Boston Molasses Disaster.
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