Earlier this year, we told the story of how a change in the White House had the potential to turn the tide for Black communities fighting against environmental pollution in Louisiana's industrial corridor nicknamed Cancer Alley — one of the country's largest hotspots for toxic air.

The Environmental Protection Agency's new leader pledged to use all the tools in his toolbox to deliver "environmental justice," and his agency launched a groundbreaking investigation into alleged civil rights violations by the state. Environmental advocates thought it could be the moment everyone waited for after years of debate over discrimination.

Then, out of the blue, the EPA dropped its high-profile investigation without any resolution. It blindsided everyone.

Today on Sea Change, we go back to Louisiana's industrial corridor to try to find some answers. Why, when the EPA was on the cusp of reforming the petrochemical state of Louisiana, did it just... back off? Turns out, the implications are even bigger than we imagined. Far bigger than Louisiana.

Reported and hosted by Halle Parker. Our managing producer is Carlyle Calhoun. Edited by Nora Saks and Carlyle Calhoun. Our sound designer is Maddie Zampanti. Sea Change is a production of WWNO and WRKF. We are part of the NPR Podcast Network and distributed by PRX.