A new leak again raised concerns about water contaminated with coal ash flowing into the Dan River on the border of North Carolina and Virginia.

The second leak of arsenic-tainted water comes from the same pond where earlier this month at least 82,000 tons of ash mixed with 27 million gallons of contaminated water — which had been stored in an unlined pond at a decommissioned Duke Energy plant in Eden, N.C. — escaped through a damaged storm drain into the river. The spill caused concerns about the water quality for residents who rely on the Dan River for drinking water, and prompted fierce reactions from environmental watchdog groups that said the spill was indicative of too-lax regulations for coal ash.

The newly discovered leakage of arsenic-tainted water, made public by Duke Energy and the North Carolina Department of Environment and Natural Resources (DENR) on Tuesday, comes from a second stormwater pipe that also travels below the 27-acre coal pond responsible for the first spill.

DENR had issued warnings about the structural integrity of the pipe last week, but Duke downplayed those concerns, saying video footage from inside the pipe showed it was structurally sound.

“After reviewing the videotape, we determined that no immediate action was necessary,” a Duke statement said.

Duke Energy spokeswoman Catherine Butler said Duke didn’t realize the water pouring through the pipe was contaminated with arsenic-laden coal ash until earlier this week, when the company — the largest electric utility in the United States — tested the water at its outflow point.

DENR ordered Duke to plug the pipe on Tuesday. Butler said Duke was still working to completely stop the flow. It’s unclear how much water contaminated with arsenic has come out of the pipe. At the source, the arsenic levels are several times higher than federal standards allow for drinking water, but the Danville water intake is 20 miles downstream, and Danville officials said they are not concerned about the safety of the water.

But environmentalists believe there are ongoing concerns stemming from the first and second leak at the plant. Both leaks pose a continued risk to the environment, they report, and show that without stronger regulations, similar incidents are likely to happen again.

“It will have an immediate impact on the wildlife that was buried by the ash, and long-term there’s 100 percent certainty that there will be an environmental impact, but it’s not clear how far and wide that will be,” said Tiffany Haworth, the head of the Dan River Basin Association. “My concern isn’t only the removal of the ash that has spilled, and the removal from the ash at that (Duke Energy) pond, but the removal of the ash from all other ponds.”

It’s still impossible to know what the environmental impact of the two incidents will be.

Officials from the U.S. Fish and Wildlife Service said yesterday that coal ash has been detected as far as 70 miles away from the spill site, and in some cases was 5 feet deep.

"If you're a mollusk and covered with ash then, yeah, you're gonna die," Tom Reeder, North Carolina’s director of water quality, said at a meeting on Monday.

But watchdog groups say the mollusks and other animals covered in ash are just the tip of the iceberg of ash-related environmental contamination in North Carolina.

Coal ash is currently unregulated by the federal government and not listed as a toxic substance, despite the various toxic chemicals it often contains. The Dan River spill, and the newly discovered leak, are only two of many coal ash spills to happen in the U.S. in recent years.

Activists say that’s a sign that more needs to be done to regulate the substance.

The federal government is expected to release its first regulations at the end of this year. And federal authorities have launched an investigation, demanding documents from North Carolina’s DENR and Duke Energy about the Feb. 2 spill.

But at the state level, it’s unclear how soon any lasting action will come. Environmental groups have sued Duke Energy three times to clear out coal ash ponds, but each time, the groups say, the lawsuits were blocked by DENR.

This time around, activists are hoping DENR’s attitude has changed, but it’s not clear if it has. The agency has yet to announce any fines against Duke, or new regulations for coal ash. DENR says it is investigating the Duke spill.

Environmentalists say an investigation isn’t necessary to know that more needs to be done — specifically removing coal ash from unlined ponds near rivers — to protect water from future spills.

“DENR doesn’t need to stop and form a committee and reinvent the wheel,” said Amy Adams, a member of the environmental group Appalachian Voices. “How much more studying needs to be done? We don’t need studies, we need action.”