Water systems working to lower arsenic levels

As new federal standards loom on the horizon, several Licking County water treatment facilities must find ways to reduce levels of toxic arsenic in drinking water by 2006.

May 26th, 2004

By Erik Johns, The Advocate

NEWARK, Ohio, May 26, 2004 -- As new federal standards loom on the horizon, several Licking County water treatment facilities must find ways to reduce levels of toxic arsenic in drinking water by 2006.

The most recent information from the Ohio Environmental Protection Agency shows about 4,500 people in the county are drinking arsenic-tainted water from public systems that exceed the limits of the upcoming guidelines.

Current regulations allow for 50 parts per billion of arsenic to water. By 2006, that number will drop to 10 ppb.

"Recent data has given us information that (50 ppb) is no longer protective of human health," said Michael Slattery, geologist with the Drinking and Ground Water Protection Unit of the Ohio EPA.

Of the roughly 10 systems in Licking County that are currently above 10 ppb of arsenic, only one -- the Licking Valley Middle School -- is above 20 ppb.

The village of Hebron's water system has the most customers of any system that exceeds the new standard. The 2,200 recipients of that water are drinking 15.7 ppb of arsenic, according to Ohio EPA data.

This number is well below the current standard, and Hebron is preparing to upgrade its facilities to meet the upcoming standards.

Hebron Water Superintendent Charles Gray said that once the ongoing expansion for the Hebron treatment plant is complete -- hopefully sometime this summer -- regular testing to assess their arsenic situation will begin.

"Once we get this plant running, we're going to start testing," he said.

Hebron already has processes in place to reduce arsenic levels, and may have to implement additional filtration methods to meet the new standards.

Gray added that he is confident Hebron will be able to meet the future standards.

For facilities like Hebron, which comply with current regulations and are already close to meeting the new standards, preparing to make it below the 10 ppb threshold is an urgent concern.

"For those systems close to 10 (ppb), it's critical that they need more information," said Kathy Pinto, environmental specialist at the Ohio EPA.

She added that those who are way over that limit know they have a problem and are constantly testing and working to fix it, but those who are close to 10 ppb might not realize they may eventually have a problem.

"If you wait until '06 to start," she said, "then you've got a violation."

Arsenic is a naturally occurring element -- the 20th most abundant in the Earth's crust -- and little can be done to prevent it from reaching water. Therefore, removal efforts must focus on the treatment end, Slattery said.

Arsenic is mostly found in deep wells and aquifers rather than surface water sources. Water that is closer to the atmosphere -- and thus oxygen -- is less likely to contain arsenic. The introduction of oxygen sets off chemical reactions that can reduce arsenic levels. As water rests further from the atmosphere, oxygen is used up by microbes and other reactions as it works its way through the Earth, Slattery said.

Arsenic has long-term health effects if consumed in large quantities.

"It's not considered an acute contaminant," Slattery said. "It's a long-term, chronic situation."

Exposure over long periods can increase a person's risk of developing cancer as well as have effects on cardiovascular, immune and neurological systems.

Immediate health risks only exist if arsenic is consumed in massive quantities, much higher than any levels found in Ohio.

A number of different methods exist to remove dangerous levels of arsenic from water, many of which can be costly.

"There's a serious capital cost associated with putting in filtration," Slattery said. "You do have to balance reduction in potential cancer rates vs. what the system has to pay out to reduce the arsenic load."

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