The latest independent study of water quality among 11 North Carolina lakes and rivers downstream from coal-fired power plants’ coal ash ponds revealed “high levels of contaminants that in several cases exceed the U.S. Environmental Protection Agency’s guidelines for drinking water and ecological effects.”

Coal ash, the toxic byproduct of burning coal for electricity, is typically stored in wet, often unlined, ponds. The most recent study, led by Duke University and published in the peer-reviewed journal Environmental Science & Technology, examined discharges from these ponds and how they affect lakes and rivers at different upstream and downstream points.

Each new page in the Coal Ash Chronicles is dripping with more arsenic-laced water than the last.

Arsenic concentrations in water flowing from coal ash ponds at Duke Energy’s Riverbend power plant into Mountain Island Lake, a primary drinking water source for Charlotte, were nine times higher than the federal drinking water standard. Near Asheville, coal ash pond discharges flowing into the French Broad River from Progress Energy’s Arden power plant had arsenic levels four times higher than the federal drinking water limit. Although this doesn’t mean that these cities’ drinking water itself is as contaminated as the discharge points, it shows a pattern of unacceptably high pollution from coal ash dumps.

The researchers’ surface water findings are likely unsurprising to folks who are familiar with the results of state groundwater monitoring near the 14 North Carolina power plants with unlined coal ash ponds that have found frequent exceedances of groundwater standards.

Affirming that coal ash pollution also causes costly damage to fish and wildlife, a study published in the same journal this August found that, “The combined direct and indirect cost of poisoned fish and wildlife exceeds $2.3 billion, which is enough money to construct 155 landfills with state-of-the-art composite liners and leachate collection systems,” and that cost is projected to increase by an additional $3.85 billion over the next 50 years. Following this report, the latest Duke University study brings new causes for alarm.

Laura Ruhl, Avner Vengosh, and other study authors found levels of arsenic in Mountain Island Lake sediment that were roughly 25 times higher than current EPA standards for drinking water, and nearly twice the EPA standard for aquatic life. Researchers also found that coal-fired power plants that use scrubbers to control air pollution often discharge water with higher levels of selenium, a toxin that can cause neurological damage to humans at high exposure levels. Dangerous byproducts of burning coal, such as selenium, are being transferred from air pollutants into coal ash, and because coal ash is not regulated as a hazardous substance, these byproducts are leaching into water supplies.

The Duke University study bolsters citizen concerns about public dangers from lax oversight of coal ash, and comes just days after the Southern Environmental Law Center and a coalition of environmental groups filed suit against the N.C. Environmental Management Commission. The groups are seeking legal orders to make Progress Energy Carolinas and Duke Energy Carolinas clean up known groundwater contamination at 14 power plants’ ash dumps.

In other coal ash news this week, concerned Mecklenburg County residents with the grassroots group We Love Mountain Island Lake are hosting a community meeting featuring a panel discussion on the lake’s water quality. Panelists include Rusty Rozzelle, Charlotte Mecklenburg water quality manager and Sam Perkins, director of technical programs for the Catawba Riverkeeper.

The meeting is Thurs., Oct. 18 at 7:30 p.m. at Cook’s Memorial Presbyterian Church in Fellowship Hall. The address is 3413 Mt. Holly-Huntersville Road, Charlotte, NC 28216