RALEIGH, NC (AP) _- A team of academic researchers equipped with a drone estimate that about 35 million gallons of coal ash and contaminated wastewater spilled into the Dan River earlier this month.
Wake Forest University researchers released results Tuesday from a study using photos collected by the drone that flew over the Duke Energy coal ash dump that ruptured Feb. 2 in Eden. The scientists used images captured by the drone to create a digital three-dimensional model of the pit, allowing them to calculate the volume of toxic ash that flowed out when a pipe collapsed.
The reported amount equals about 53 Olympic-sized swimming pools, making it the third largest coal ash spill in the nation's history.
The independent measurement is within the broad range that Duke's engineers had initially estimated.
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