GREENSBORO, N.C. — The air in the Shiloh Baptist Church was thick with the heat of human bodies. The crowd, a mix of black and white faces, filled the pews in what was ostensibly the black side of town, straining the capacity of this good-sized church.
On the dais stood the Rev. Dr. William J. Barber II, draped in a black robe, a black vest and a cream stole emblazoned with the credo “Jesus was a poor man.” Al Gore, the former vice president, sat behind him.
Dr. Barber’s message to the community members in the church last week would have been largely recognizable to civil rights leaders of generations past, addressing issues of poverty and racism. But he and Mr. Gore were here in Greensboro to focus on another concern that many in the audience believed was just as insidious: pollution from North Carolina’s coal-powered electrical plants.
“Jesus said love your neighbor,” Dr. Barber told the crowd. “I don’t care how many times you tell me you love me, if you put coal ash in my water you don’t love me. Because if there was nothing wrong with the coal ash, then put it in the wealthy communities.”
Fifty years after the Rev. Dr. Martin Luther King Jr. started a movement known as the Poor People’s Campaign, Dr. Barber has been working to revive it. He is perhaps best known as the architect of the Forward Together Moral Movement protests in North Carolina that opposed voting-rights restrictions and helped defeat the Republican governor in 2016. Now he is making environmental justice, and climate change, a pillar of a modern-day war on poverty.
Dr. Barber and Mr. Gore spent two days touring nearby towns, drawing attention to environmental issues and making it clear that voters could act on them come Election Day. Lower-income communities — especially black, Hispanic and Native American ones — tend to be more polluted and bear more of the burden of climate change than higher-income and white communities, experts say.
Dr. Barber rejected the notion that these were partisan issues. “This is the real question, not if Democrats are going to get elected, not if Republicans are going to get elected, but if America is going to be America, she’s going to have to address systemic racism, systemic poverty, ecological devastation, the war economy and militarism, and our false moral narrative of religious nationalism,” he said.
Mr. Gore, well known for his work on global warming, said the issues of coal pollution and climate change were linked. “Both are necessary byproducts of our addiction to fossil fuels,” he said.
The two men visited Belews Creek, a predominantly black community in a predominantly white county that resides in the shadow of the Belews Creek Steam Station, a coal-fired power plant.
All coal plants generate coal ash, the hazardous powdery substance that remains after burning coal. Many plants, including the Belews Creek facility, store it on site, mixed with water in storage ponds. But a lawsuit filed in December says because the active storage pond at Belews Creek lacks a protective lining, it is seeping into the groundwater.
The E.P.A. links the substances in coal ash — including heavy metals like arsenic and lead — to nervous-system problems, reproductive issues and cancer. Still, the agency last month overhauled Obama-era regulations on coal ash disposal, granting more authority to states and industry. Separately, the E.P.A. this week loosened rules on air pollution from coal plants and estimated the change would result in up to 1,400 premature deaths annually by 2030.
“I think most people assume that when you live in the country that you would have clean air and water,” said Danielle Bailey-Lash, who moved to Belews Creek in 2005 but left in 2015 after she learned she had brain cancer. She does not know whether coal pollution or other factors caused it.
Belews Creek is a prime example of the kinds of communities threatened by coal ash pollution, said Lisa Evans, a lawyer for the environmental group Earthjustice. “Coal ash ponds are in rural areas, particularly in the Southeast. Those communities have less power and less of a voice,” she said.
“Those are the areas that do not have municipal water systems to filter and clean the water,” Ms. Evans added. “When you contaminate groundwater in a rural area, that’s their lifeline.”
The lawsuit says that Duke Energy, the plant’s owner, is dumping untreated coal ash pollution directly into surface water at the Belews Creek plant, and that the coal ash pond is leaking into surface water and the connected groundwater. The plaintiffs include the environmental group Appalachian Voices North Carolina and the state and county branches of the N.A.A.C.P.
A federal district judge last week denied Duke Energy’s motion to dismiss the suit.
Duke says its studies and outside experts agree there is no evidence that the Belews Creek facility is polluting nearby drinking water wells. “We’ve got good evidence that tells us that the drinking water wells remain very safe, and that the groundwater impacts around the basin are well-defined and well understood and not impacting the neighbors,” said Paige Sheehan, a spokeswoman for the utility.
Avner Vengosh, a professor of earth and ocean sciences at Duke University, said the situation was complicated. In his research, he has found evidence of coal ash contamination in surface water in North Carolina, but has not found contamination in the region’s drinking wells.
Generally, however, unlined coal ash ponds do leak into groundwater, according to a 2016 study published by Dr. Vengosh and his colleagues. And Dr. Vengosh said his team had not tested every drinking well in the area. “Are there wells that we have not studied that could potentially have been affected? Absolutely,” he said.
Human exposure to toxins generated by coal plants can also come from atmospheric pollution and from airborne particles that settle onto surfaces, Dr. Vengosh said.
Leslie Bay Brewer, a pastor who grew up in Belews Creek, remembers what life was like in the late 1970s and early ’80s, a few years after the plant opened. Coal ash “was everywhere — the soil, the car, our roofs,” she said.
She said her children later suffered breathing problems. “Then we started to put two and two together that a lot of the neighbors were having these issues,” she said.
“There’s actually people down there that have to bathe in bottled water,” said David Hairston, a board member of Appalachian Voices and a native of the region. “That’s how fearful they are.”
In 2014, a drainage pipe collapsed under a coal ash pond at Duke Energy’s Dan River Steam Station, roughly 35 miles northeast of Belews Creek, spilling millions of gallons of sludge along 70 miles of the Dan River. It was the second-largest such disaster in the United States.
Afterward, the state ordered Duke to close 32 coal ash ponds. The company’s plan at Belews Creek is to drain the pond but leave the ash in place, filling the structure with soil and capping it with a weatherproof cover. Environmentalists want Duke to excavate the coal ash completely.
Ms. Sheehan, the Duke spokeswoman, said excavation at Belews Creek would be risky and costly. The lawsuit “was filed by a number of critic organizations who want to burden people with excavation,” she said. “Capping is supported by the science and the engineering.”
If North Carolina has a history of environmental problems, it also has a history of environmental protest.
“Where did the environmental justice movement begin?” Mr. Gore asked after taking the lectern at Shiloh Baptist. “It began right here in North Carolina in 1982 in Warren County.”
He was referring to an E.P.A. plan at the time to situate a landfill, designed to hold 50,000 tons of soil contaminated with the chemicals known as PCBs, in a community that was 65 percent black. Residents led six weeks of primarily peaceful protests, including laying in the road to block trucks.
It is not hard to draw connections to other protesters who put their bodies on the line. Less than a mile from the pulpit, a historic Woolworth’s lunch counter is now part of a civil rights museum in Greensboro. A 1960 sit-in at the segregated counter, led by four black college students, helped catalyze a movement that desegregated restaurants across the South.
Before they became famous for their protest, at least two of the group, which became known as the Greensboro Four, attended Shiloh Baptist.