The record-breaking rains that started with Hurricane Florence are continuing to strain North Carolina’s hog lagoons.
Because of the storm, at least 77 lagoons in the state have either released pig waste into the environment or are at imminent risk of doing so, according to data issued Tuesday by the North Carolina Department of Environmental Quality. That tally more than doubled from the day before, when the department’s count was 34.
When a pig in a large-scale farm urinates or defecates, the waste falls through slatted floors into holding troughs below. Those troughs are periodically flushed into an earthen hole in the ground called a lagoon in a mixture of water, pig excrement and anaerobic bacteria. The bacteria digest the slurry and also give lagoons their bubble gum-pink coloration.
North Carolina has 9.7 million pigs that produce 10 billion gallons of manure, mostly on large-scale farms, primarily in low-lying Sampson and Dupin counties. Both counties were affected by Florence.
When storms like Florence hit, lagoons can release their waste into the environment through structural damage, for example, when rains erode the banks of a lagoon and cause breaches. They can also overflow from rainfall or be swept over by floodwaters.
Whatever the cause, the result when a lagoon leaks can be environmental trouble. If the untreated waste enters rivers, for example, algal blooms and mass fish die-offs can happen, as they did in 1999 during Hurricane Floyd. That year, many animals drowned in lagoon slurry.
Hog lagoons and the associated large-scale farms, also known as concentrated animal feeding operations, or CAFOs, have been a sore spot in the eastern part of the state where residents say that the operations harm their health and well-being.
A recent Duke University study published online this week found that those complaints may have some merit.
“Life expectancy in North Carolina communities near hog CAFOs remains low, even after adjusting for socioeconomic factors that are known to affect people’s health and life span,” Dr. H. Kim Lyerly, a professor of cancer research at Duke, said in a statement. The Duke study stops short of drawing a causal link.
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Last week, Andy Curliss, chief executive of the North Carolina Pork Council, said that the pig producers had learned a lot from Hurricane Floyd. In 2016, Hurricane Matthew caused 14 lagoons to flood but none breached, according to the pork council.
“A lot of the farms that were flooded were bought out and closed,” he said. “That’s why you didn’t see the same impact in Matthew — we had maybe 15 floods, no breaches.”
As of Tuesday afternoon, the North Carolina Pork Council’s website listed only 26 lagoons as affected by the storm, far fewer than the number cited by the Department of Environmental Quality.
As Florence approached, farmers tried to free up more space in lagoons ahead of the storm by spraying manure onto fields, said Heather Overton, a spokeswoman for the state’s Agriculture Department.
Will Hendrick, a staff attorney with the environmental nonprofit group Waterkeeper Alliance, said that manure sprayed on fields could run off into rivers, streams, and groundwater supplies if the fields flooded.
Excess nitrates in groundwater, such as those associated with pig manure, are linked with health problems such as blue baby syndrome. In some cases of the syndrome, nitrogen binds to the hemoglobin in a baby’s blood and makes red blood cells unable to carry oxygen. The syndrome’s name comes from the fact that the lack of oxygen causes the baby’s skin to take on a bluish tint. The syndrome can also be caused by heart defects.
Part of the problem, said Alexis Andiman, an associate attorney with the environmental nonprofit law firm Earthjustice, is that storm standards for pig lagoons currently date from the 1960s.
As part of a settlement for a lawsuit that Earthjustice levied against the state, “the storm standard will be tied to a National Oceanic and Atmospheric Administration standard from 2006,” Ms. Andiman said. “But that’s still kind of old.”
The Department of Environmental Quality’s data is self-reported by farmers, many whom may have left their farms to avoid the storm surge and floodwaters. The number of spills reported could increase as more farmers make their way back to their farms. But luckily, in a region that has struggled with too much rain, the rest of the week’s forecast is mostly sunny.
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