A major tunnel used to smuggle drugs across the U.S.-Mexico border will soon be closed for good.
Work crews contracted by the U.S. Border Patrol dropped concrete slurry into openings above a tunnel that was first discovered on Nov. 15, 2011.
Agents seized more than 14 tons of marijuana from the tunnel running underneath the border between Tijuana and warehouses in an Otay Mesa industrial park, according to Immigration and Customs Enforcement (ICE).
The tunnels are filled once they are no longer needed by the San Diego Drug Tunnel Task Force comprised of Border Patrol and ICE agents along with Drug Enforcement Administration investigators.
'The workers map out the tunnel and dig holes in there and fill it with concrete slurry to maintain the integrity of the ground so the tunnel can’t be used ever again," said Jerry Conlin, U.S. Border Patrol Sector Spokesperson.
The tunnel, said to be the length of four football fields, ran between two storage buildings officials said.
Workers can only fill the portion of the tunnel on the U.S. side.
The tunnel remediation takes anywhere from four to eight days, Conlin said.
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