Starting in the 1970s, the textile mills of northwest Georgia relied on chemicals known as PFAS to add stain resistance to the carpets they manufactured. Some of the chemicals that didn’t stick were flushed with the multibillion-dollar industry’s wastewater into local sewer pipes and, eventually, the region’s rivers.

Decades later, the odorless, colorless chemicals are now found everywhere in the area, including in the blood of some people. Scientists have warned of health risks to humans and wildlife.

While the federal government doesn't yet have enforceable limits on PFAS, states have the authority to protect public health and the environment.…