Chemist, town resident says perchlorate
‘ion-exchange’ filter economical, not experimental, used by millions; including
at Cape Cod military installation
by Prof. William Moomaw, Ph.D.
The author is a chemist
with a PhD from MIT. He taught
chemistry and conducted research at Williams College for 26 years.
He has used ion exchange technology in the lab and in in his home.
He is currently a professor at Tufts University, where he is thd s senior
director of Tufts Institute of the Environment. A Williamstown
resident, Moomaw served on the town’s planning board in the 1980s. 617-627-2732, firstname.lastname@example.org
Ion exchange is
recommended along with more complex biological treatment as a principle means
for removing perchlorate. In fact, this is the technology of choice for
purifying vast quantities of groundwater at the Massachusetts Military
Reservation on Cape Cod.
resins are used to soften water and remove toxic impurities to protect drinking
water, remediate contaminated ground water and to reach low levels of
contaminating ions for critical industrial processes.
The process is
not experimental. There are literally many millions of homes in the United States that use this technology,
which has been available for more than
50 years, and is proven and reliable. It is also inexpensive ($0.30 - $0.80 per 1,000 gals.),
and can be installed in a very short period of time. Systems are modular
and come in sizes for a single water faucet up to systems that can treat
thousands of gallons per day.
High levels of perchlorate are known to cause thyroid damage. There is no
set standard for perchlorate, but a recommended level of no more than 1.ppb has
been tentatively set by US EPA while a standard is being set. This is a very conservative
There are two different ion exchange systems. Each is capable of removing
perchlorate down to the 1 ppm pr better, and one is supposed to reach the limit
of detection level of 0.35 parts per billion (ppb) as defined by US EPA.
manufacturer, Rohm and Haas has developed a special ion exchange resin
especially for perchlorate that is claimed to be the most efficient available.
(1-800 RH Amber)
Rohm and Haas resin is tuned to pick up perchlorate. A company official
contacted by the author on Nov. 23, 2004, said the company would want to have a
chemical analysis of the water from the well where it is applied. But except in
very unsusual situations, the resin typically brings perchlorate down to an
undetectable level which is 0.35 ppb – or roughly one third of the 1.0 ppb
standard that the EPA is talking about as a presumed safe standard.
company official said the minimum amount of resin sold comes in a 7-cubic-foot
drum, which costs $588 per cubic foot, or $4,116 plus freight from
Pennsylvania.The company said one cubic foot will treat 2 gallons per minute of
drinking water. In terms of the resins, this means approximately a $2,500 a
year cost to change resins. Money is available from the state agency which
oversees school construction as part of renovation initiatives and the money is
also available on an emergency basic. It is our responsibility to the children
and staff at Mount Greylock to check out these opportunities and possibilities
in order to resolve this problem as quickly as possible.
resin technology is available to consumers generally. For example, on my tap at
our second home in the Boston area, I have a water-purifying unit, widely
available in the Boston area, which removes a wide range of potential
contaminates, including perchlorates. It costs me $200 for the whole system and
less than $100 a year to replace the resin filter.
Further information may be obtained from Kris Kurley
of the Impact Area Groundwater Study
Program 508-968-5626, Ellie Grillo, Mass. Dept. of Environemntal Protection; or Jim Murphy, USEPA,
617-918-1028. There is also a website www.groundwaterprogram.org. A
summary of 65 perchlorate treatment studies for groundwater is available online