“Although too early to tell, if the landfill liner is breached, contaminates from the dump could leak into the Florida Aquifer where some people get their drinking water,” said Patricia Berry with Solid Waste Management during a media briefing in connection with a possible sinkhole at the Southeast Hillsborough County Landfill on C.R. 672 in Lithia.
Berry added that authorities called to the scene have no proof that the liner has been punctured, but a depression in the landfill was discovered on Tuesday, December 14 by the county’s public utilities department workers, which at the time measured approximately 50 feet across and 4 to 5 feet deep was growing.
Within 24 hours the hole dropped 45 feet, growing to 75 feet across and 50 feet deep with no signs of stopping.
“The cracks around the perimeter got wider and then the ground just started going down with smoke coming out of the middle,” said landfill supervisor, Larry Ruiz, who was surveying the initial depression when the ground gave way, sinking more than 40 feet of waste into the earth.
“We don’t know at this time if there has been a breach in the bottom liner,” Berry said but added that Public Utilities officials believe that the hole was not caused by normal settling.
This is the first sinkhole at the facility, which has opened its door to serve the county in 1984.
Berry emphasized that the daily operations of the facility have been diverted to other areas of the landfill and a segment of a nearby service road has been closed. A portion of the active landfill gas collection system has been shut off within the area impacted by the sinkhole and state and local officials, environmental agencies as well as county safety officials have been immediately notified.
“There is a system of groundwater monitoring wells in operation of this facility,” Berry said. “We will be stepping up our monitoring program.”
The landfill is located on 3,300 acres at 15960 C.R. 672 in Lithia.
The area of the sinkhole contains a mix of municipal solid waste and ash from the county’s resource recovery facility.
The DEP is supposed to survey the scene on Thursday. That agency along with SWFMUD will help county authorities execute an action plan.
For more information, please visit www.hillsboroughcounty.org.