Eastern North Carolina is drowning in pig waste. Around many pig farms are big, smelly lagoons filled with all kinds of biological horrors produced by the pigs. The waste is rich in both nitrogen and bacteria, smells awful, and if anyone falls into the waste, they slowly sink until beneath the surface and suffocate. Pulling them out is literally futile, and anyone who tries will likely suffer the same fate.
The lagoons are sealed with plastic wrap at the bottom, but some of the wrap has ruptured from contact with a rock. As a result, the trees in the area are neon green from the nitrogen. Plants are over fertilized, and the bad smell prevents the locals from enjoying food.
Though my first thought was a Below ground methane digester, it seems a waste to lose the nitrogen like that. Crop farmers are paying big bucks to nitrogen-ize the crop soil, while over here the soil is over-nitrogen-ized. Since the waste is liquid enough to flow, slowly, downhill, this could be used to transport the waste, if the receiving farm has a solar-powered lifting device.
That or the local towns could replace themselves with robotically harvested cotton and tobacco farms, both of which demand quite a lot of nitrogen fertilization.