When a deadly explosion destroyed BP’s Deepwater Horizon drilling rig in the Gulf of Mexico, 134 million gallons of crude erupted into the sea over the next three months — and tens of thousands of ordinary people were hired to help clean up environmental devastation from the biggest offshore oil spill in U.S. history.

These workers were exposed to crude oil and the chemical dispersant Corexit while picking up tar balls along the shoreline, laying booms from fishing boats to soak up slicks and rescuing oil-covered birds.

Recognizing that some members of cleanup crews had likely become sick, BP agreed to a medical claims settlement two years after the 2010 disaster. Experts hailed it as “an extraordinary achievement” that would compensate workers fairly with little hassle.

But it hasn’t turned out that way.

The effort has fallen far short of expectations, leaving many workers who claimed lasting health effects stranded with little or no payment.

Through the settlement, BP has paid ill workers and coastal residents a tiny fraction — $67 million — of the billions the company has spent on restitution for economic and environmental damage. The vast majority — 79% — received no more than $1,300 each.

Many workers claiming illnesses from the spill were forced to sue — and they’ve fared worse. All but a handful of roughly 4,800 lawsuits seeking compensation for health problems have been dismissed.