Watch the full-length episode at http://video.pbs.org/video/2365411270/?Utm_source=youtube&utm_medium=pbsofficial&utm_campaign=nova_covefullprogram (US Only) The catastrophic collapse of the ground beneath our feet is a growing worldwide hazard.
Airing January 28, 2015 at 9/8c on PBS.
NOVA | Sinkholes—Buried Alive | PBS
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