The lined earthen pits that hold treated waste had been a major environmental concern as unprecedented rain falls.

Record-setting, still-rising floods are preventing a comprehensive assessment of damage from Hurricane Florence.

The deluge has already killed at least 13 people and left entire communities under water.

Catastrophic flash floods are likely in the Carolinas and Appalachians through early next week.

More than 20 inches of rain have drenched the region, and the total may reach 40 inches in some areas.

Rail accidents killed 775 people in the U.S. last year, up from 748 in 2015, according to figures from the Federal Railroad Association.