As money pours in to pay for water quality fixes in York County, experts insist public health wasn't in danger prior to Clean Water Act violations and it isn't in danger now.
"There was never a risk to public health from drinking water treated at Rock Hill Water Filter Plant," said Katie Quinn, spokesperson for the city of Rock Hill. "The city reacted immediately to address elevated bromide levels and these actions kept the drinking water produced at the plant safely within the prescribed limits."
In 2014 and 2015, York County had issues keeping levels of disinfection byproducts within regulatory limits. When organic material in water meets disinfectants, particularly given time and higher temperatures, byproducts form. Rock Hill, which draws water from Lake Wylie and distributes it to the county and other users, had the same issue.
The common issue suggested something could be off with Lake Wylie, rather than each water distribution system.
In May 2015 Duke Energy pleaded guilty in federal court to nine misdemeanor violations of the Clean Water Act. Part of that plea involved Duke agreeing to pay local governments downstream of their facilities if the utilities showed "substantial increases" in the byproduct caused by bromide discharges at Duke sites.
The money would reimburse water suppliers for extra work needed to maintain byproduct levels within a safe range, according to environmental standards.
Last November, Rock Hill notified a court-appointed monitor it would seek compensation. In January the city and Duke reached a $3.5 million settlement which also included money for Rock Hill's wholesale customers. York County Council voted Monday night to accept its share from Rock Hill, more than $27,000 for improvement.
David Hughes, water and sewer supervisor for York County, said Rock Hill has the much larger role in the matter given the city withdraws the water that goes to about 100,000 customers in that city, York County, Fort Mill, Tega Cay and Lake Wylie (through Carolina Water Service).
"We basically take the water Rock Hill treats and distribute it," Hughes said.
Despite the settlement, Duke asserts public health wasn't and isn't at risk.
"Duke Energy proactively addressed bromides in the Catawba River basin two years ago, and it does not pose a concern for drinking water quality," said Bill Norton, company spokesperson.
Bromide occurs naturally. It's a trace element in the earth's crust, and in sea water. It can be found in low amounts in surface water and in rain. It's also in coal, and is found in greater amounts where fossil fuels interact with water.
A study listed on the Environmental Protection Agency website details coal power plant bromide discharges and their impact on drinking water. It states bromide concentrations impacting drinking water plants are "generally very low."
It also states plants can't "easily remove" bromide, and exposure to the byproducts is associated with an increased cancer risk, low birth weight and developmental abnormalities.
Bromide isn't regulated by the Clean Water Act. The concern is the byproduct it helps form. Those byproducts are regulated.
"Bromide is commonly discharged to surface waters across the nation through industrial and municipal wastewater treatment processes," Norton said. "Duke Energy participated in a refined coal program for a short period from August 2012 to May 2015 at the Allen and Marshall plants to help reduce mercury air emissions, which increased our bromide discharges."
Norton said despite there not being limits on bromide discharges, Duke stopped using refined coal at the Allen (on Lake Wylie, in Belmont, N.C.) and Marshall (Lake Norman) plants "as soon as we learned" about downstream issues.
"We quickly met with them when we learned of their challenge, exchanged monitoring data and proactively worked through the bromide issue," Norton said. "The operational changes we made had great results for river water quality, dramatically reducing the level of bromide."
The safety of drinking water is at this point, Norton said, consensus.
"Our regular testing of surface waters on Lake Wylie shows water quality is safe," he said. "Separately, water providers around Lake Wylie conduct thousands of lab tests annually and can confirm drinking water supplies are safe."
Rock Hill offers the same thought.
"There's no current public health risk related to bromide discharges," Quinn said. "Since the discovery of elevated bromide in 2014 in Lake Wylie, the city's raw water source, the city began monthly testing to monitor bromide levels in the raw water source. These levels have decreased tremendously."
Monthly readings show bromide levels are "consistently" at about 3 percent of the maximum amount allowed by environmental regulators, Quinn said. Annual testing includes collecting samples from seven sites along the basin feeding into the Rock Hill intake.
Even when bromide levels were high, the issue was equipment and effort to get discharge levels within compliance, not worry that discharges would be unsafe downstream.
"The city monitors the raw water source daily to ensure that the water quality is safe and stable, and can adjust treatment processes as needed to address anything out of the ordinary," Quinn said.
For its part, York County had to perform additional water testing at more than $1,700 and install a mixer at the New Heritage Elevated Storage tank costing more than $29,000.