• Drone used to estimate size of NC coal ash spill

    RALEIGH, N.C. (AP)

    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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