"For decades, some big polluters were allowed to estimate their emissions using methods the government knew were often unreliable. Air monitors at coke manufacturers, chemical plants and other industrial facilities showed far higher emissions than the estimates, records viewed by ProPublica show. The Trump administration has halted rules requiring more than 130 industrial plants to install air monitors and comply with new emission standards."
"For decades, noxious, cancer-causing gases poured from some of the nation’s largest industrial polluters, seeping invisibly from cracks in antiquated pipes or billowing out of smokestacks in plumes that choked the communities nearby.
And for decades, the Environmental Protection Agency tracked those emissions not by monitoring the air but by relying on a kind of honor system. Companies were allowed to estimate their chemical pollution using methods that even the EPA conceded were often unreliable.
In 2023, the EPA received irrefutable proof that these estimates were highly flawed. The agency had required 20 industrial facilities to temporarily install air monitors around their perimeters — known as fence-line monitoring — to see how bad the pollution actually was.
The results, compiled now for the first time by ProPublica, were shocking."
Lisa Song reports for ProPublica October 30, 2025, with photography by Annie Flanagan.
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