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EXCLUSIVE: Corrosive groundwater raises risk of lead exposure in SC

Corrosive water can increase chances of lead getting into tap water
Corrosive water can increase chances of lead getting into tap water

South Carolina’s sandy midsection contains some of the country’s most acidic, pipe-corroding groundwater, but many small utilities aren’t treating drinking water to prevent lead from washing off pipes and into people’s taps.

About two-thirds of the utilities that rely on groundwater in the Columbia area do not use treatment methods that can protect drinking water from lead, records show.

In several cases, utilities not using corrosion controls have exceeded federal safe drinking water standards for lead contamination, according to S.C. Department of Health and Environmental Control records.

Previously used in water supply pipes, lead is a toxin that causes brain damage in children, even if consumed in microscopic amounts. Acidic groundwater, like that found in Richland and Lexington counties, can corrode pipes containing lead.

DHEC officials said Friday that 60 of 96 community water systems relying on wells in Richland and Lexington counties do not use corrosion controls to protect drinking water. Those systems regularly serve homes and many businesses across the Columbia area.

But the number is higher when other types of water systems are considered, including small local systems that supply rural convenience stores, gas stations and campgrounds, records show. Overall, up to 124 water systems in the Columbia area aren’t using corrosion controls, according to department records reviewed by The State newspaper.

Collectively, these systems provide drinking water to as many as 10,000 people in the two counties, records show.

One state lawmaker said the lack of corrosion controls in South Carolina is disturbing. But DHEC spokeswoman Cassandra Harris said her agency can’t force all small water systems to install corrosion controls.

Groundwater systems that meet the U.S. Environmental Protection Agency’s drinking water requirements for lead “are not required to add’’ corrosion controls, Harris said. Federal law requires small utility systems to take steps to control lead, including corrosion controls, after lead levels exceed the federal drinking water standard.

South Carolina has some of the most corrosive groundwater in the country because of the highly acidic water in the middle part of the state, according to the U.S. Geological Survey, which released a national report about corrosive water last week. The areas of concern include Columbia, Aiken and Florence. The report listed South Carolina, Alabama and Georgia as having the South’s most corrosive groundwater.

Although more than 200,000 state residents are served by several hundred groundwater systems that don’t treat water to control lead, corrosive groundwater isn’t as big a concern in the Upstate and Lowcountry because the water there generally is less prone to cause corrosion, state and federal officials said.

Harris emphasized that 98 percent of state residents get their water from systems with corrosion controls. Even though small groundwater systems don’t always have to treat water for lead, all of the state’s largest water systems must do so, the agency said. Treatment often involves adding lime or phosphate to raise the pH level so that the water won’t flake lead from pipes.

Not good enough

State Rep. Joe Neal, D-Richland, said corroding pipes threaten human health – particularly in rural areas with highly acidic groundwater like that found in the Midlands. Many poor, out-of-the-way neighborhoods are served by questionable drinking water systems, he said.

“What we end up with is trickle-down poisoning,’’ Neal said. “I call it trickle-down because the water slowly leaches that lead out of the pipes and into drinking water. We end up with a growing problem. It starts out small and becomes very serious as time goes by.’’

More than a decade ago, Neal pushed to secure better drinking water for a community that had been exposed to lead for parts of 20 years. Some residents of the Franklin Park subdivision had elevated levels of lead in their blood, including a young child.

Since the 1980s, DHEC had failed to force the private water company serving Franklin Park to install corrosion controls. Richland County took over the water system in 2005 and began treating the water, which cleared up the lead problems within a year, The State newspaper reported in 2006.

Neal said treating water after lead shows up is gambling with public health. If DHEC can’t ensure treatment is added to drinking water when corrosion controls are needed, the state needs to look at strengthening South Carolina’s law, he said.

“This needs to be preventative, not remedial,’’ he said.

Leigh-Anne Krometis, a Virginia Tech professor who has studied lead in rural water systems, said large water systems typically receive more attention when lead questions surface because they are more complex and serve more people. But that doesn’t mean lead threats should be discounted in smaller, community water systems or in private wells, she said.

“Of course it matters,’’ said Krometis, who works with Marc Edwards, the Virginia Tech professor credited with uncovering the lead crisis in the Flint, Mich., water system. “I don’t want anyone to be drinking low quality water, especially something like lead. Exposure to lead (is) entirely preventable.’’

This year, lead contamination has been a concern in South Carolina since DHEC released records showing that more than two dozen small water systems had exceeded safe drinking water standards for lead since 2011.

About half of those violations were found in the central part of the state, mostly in Richland and Lexington counties. DHEC said at the time that it suspected corrosive water contributed to the problem.

Lead is rarely found in groundwater, so it almost always gets into drinking water as the water flows through metal pipes and plumbing fixtures that contain lead.

David Baize, DHEC’s water bureau director, said some water systems and homes in South Carolina are now using pipes made out of plastic or other material, meaning there is substantially less chance lead could get into drinking water even if the water is corrosive. Since 1986, the federal government has curtailed the use of lead solder in pipes and restricted the lead content of pipes.

“You don’t add chemicals to water if you don’t need it,’’ Baize said. “Adding chemicals to water systems is expensive, it takes an operator to do it correctly and it could even be a problem in and of itself.’’

But Baize said DHEC does not know how many old, lead-containing pipes have been changed out over time. When utilities replace lead service lines, they typically don’t include the plumbing that directly serves people’s homes. Pipes inside homes, as well as faucets, can contain lead solder or other materials.

Krometis said corrosion controls are important to protect drinking water when lead pipes are still in service.

“You want to protect the long-term integrity of your pipes,’’ she said. Any material in the pipe can end up in the water if it’s corroding, she said.

That’s why many systems add treatment to limit the acid levels in water.

High lead levels discovered

Federal law says that any time a water system exceeds the national standard of 15 parts per billion of lead in the water, it must take action to address the problem. That includes installing treatment to limit corrosion of pipes.

But water systems can drop corrosion control studies if later tests show that lead levels have fallen to within safe standards, DHEC officials said Friday.

In the Columbia area, some small water systems have exceeded the safe drinking water standard for lead but did not install corrosion controls.

In one case, a small Lexington County water system, identified as serving the Ridge Point subdivision, has exceeded the lead standard two times in the past five years, according to DHEC records released this past spring.

Mike Swearingen, an official with the company that runs the water system, said the water was tested when the system was first installed years ago “and treatment was not needed.’’ Installing corrosion controls isn’t expensive, but keeping up with a treatment system can be costly over time, said Swearingen, whose family runs the AAA well drilling company.

“All the other things start adding up,’’ he said.

Another system in Lexington County, identified as serving the Triple Acres mobile home park, exceeded the lead standard once in 2013, agency records show. Triple Acres, located near the Columbia Metropolitan Airport, also is not listed as adding corrosion controls to the water. Efforts to reach a company official were unsuccessful Friday.

Baize said his agency is trying to determine whether lead found in those systems came from corroding pipes. The review is part of a statewide study of water systems with elevated lead levels.

Wes Gray, who owns the 22-space Piney Lane Mobile Home Park and its water system, said he spent $25,000 on water system improvements when he purchased the Eastover-area park about five years ago. But he said he doesn’t know what types of pipes serve each mobile home and DHEC never told him he needed to treat the water for lead.

“I’ve had no directive from DHEC,’’ he said.

The Piney Lane system exceeded the safe drinking water standard for lead once in 2015, DHEC records show. The frequency of testing varies, but can occur every six months.

In a series of emails this week, DHEC emphasized that all large utilities, or those serving more than 50,000 customers, must install corrosion controls. The department also said anyone concerned about lead in the water can let taps run for 15 to 40 seconds before drinking the water.

Even though two-thirds of the groundwater-fed drinking water systems across South Carolina don’t use corrosion controls, DHEC said the population they serve is small. The agency also said that most water systems in South Carolina have not had lead violations, although records show it’s not unusual for systems to register some levels of lead.

“It’s important to note that of the 3,851,595 people served by community public water systems in the state, 98% (3,487,469 people) currently receive water that has corrosion control treatment,’’ Harris said in an email.

Lead has recently been a national concern in the aftermath of the Flint, Mich., drinking water crisis that surfaced last year. There, corroding pipes contributed to dangerously high levels of lead in drinking water.

Groundwater is more acidic – and corrosive – in the central part of South Carolina because aquifers that supply wells are closer to the surface than those in the Lowcountry.

Since rainfall is acidic, that means groundwater in the Midlands is more likely to remain acidic than groundwater in the Lowcountry, where aquifers are deeper and the acid is neutralized over time. Rain in that area typically does not get into the deep Lowcountry aquifers. Upstate groundwater isn’t as acidic because the rocky subsurface helps cleanse the water there.

Limit lead risk

  • Run faucets 15 to 40 seconds in the morning before drinking water.
  • Change pipes and well pumps to lead-free materials, such as PVC pipe.
  • Install corrosion control treatments if lead pipes can’t be removed.
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