SCE&G is investigating recently discovered leaks of a poisonous, cancer-causing metal near its lower Richland power station several miles upstream from Congaree National Park.
But company officials don't think the arsenic contamination has been occurring for years - as was suggested this week in court.
Inspections from 1999 until last month did not find evidence that polluted water was seeping from a waste pond through a bank along the Wateree River, said Tom Effinger, who manages environmental services for SCE&G's parent company.
"We have those records of inspections by the folks who went out there annually and looked," Effinger said. "They signed off and they certified ... they didn't see it."
Effinger, a SCANA representative, made his comments Thursday at the end of a contentious, three-day hearing over SCE&G's plan for a mega-landfill.
The company is seeking state permits for the disposal site and river discharge at its U.S. 601 power plant along the Wateree River near Eastover.
Two consulting companies, including one hired by SCE&G, found high levels of arsenic seeping out of an embankment last month between an existing coal ash waste pond and the Wateree River. Arsenic-polluted ash is produced by burning coal to make power. Coal residue goes into a waste pond.
The September discovery was in the same area where arsenic-polluted drainage was documented leaking toward the river in 1997. The most recent leaks contained even more arsenic.
Lawyers for landfill opponent Heath Hill said SCE&G and the S.C. Department of Health and Environmental Control have done little to stop the seepage and clean up groundwater beneath a coal waste pond that has exceeded safe-drinking water limits for arsenic for years.
Granting new permits for the landfill and river discharge is illegal because it would worsen the pollution, Hill's attorneys say. More pollution threatens private drinking water wells, irrigation systems and land values, Hill says.
Administrative Law Judge Carolyn Matthews is expected to decide by early December whether to uphold the environmental permits Hill is challenging.
"I don't understand why SCE&G didn't do more," attorney James Smith, an S.C. House member representing Hill, said after court. SCE&G "has all these resources" to do the cleanup, he said.
SCE&G is the prime subsidiary of SCANA, a $10 billion Fortune 500 holding company. The power company, headquartered in the Columbia area, has 652,000 retail and wholesale customers.
Effinger and Jim Landreth, who oversees coal-fired power plants for SCE&G, dismissed allegations the company has been negligent.
Effinger questioned whether recent samples of arsenic-polluted drainage were accurate since arsenic also occurs naturally in mud and dirt. Landreth testified he has never personally seen water seeping from the hillside toward the river during five visits he has made to the site since 2000.
Landreth said he was aware of seepage in the late 1990s, but could not say whether SCE&G took action to address the finding at the time.
Landreth said SCE&G is trying to pinpoint the source of the leaks found last month and to do any cleanup necessary. The arsenic levels documented near the river last month were as high as 1,900 parts per billion, more than five times the state surface-water standard for aquatic life.
"That is a concern," Landreth said.
Smith and co-counsel Bob Guild said evidence shows the pollution is coming from the coal ash pond. The pond is not far from the river and already has polluted groundwater in the area to levels that have exceeded the federal safe drinking water standard of 10 parts per billion for arsenic, records show.
Like SCE&G, other utilities that burn coal and dump the arsenic-riddled waste ash into ponds have been under scrutiny since an ash pond spilled in Tennessee last year.
Smith noted that SCE&G's recent report to the Environmental Protection Agency did not disclose seepage in the 1990s. SCE&G officials said it wasn't required.
Arsenic is a metallic element long known for its poisonous effects. Certain forms cause cancer when people are exposed over time. High doses also can cause vomiting and skin disorders. Although naturally occurring, arsenic is released from coal when burned to make electricity.