SEFFNER, FL - MARCH 1: A crowd gathers at the home of Jeff Bush after he was consumed by a sinkhole while lying in bed last night, March 1, 2013 in Seffner, Florida. First responders were not able to reach Bush after he disappeared and now say it is a recovery mission. (Photo by Edward Linsmier/Getty Images)
Engineers on Saturday continued probing the ground around the sinkhole that swallowed a Florida man from inside his bedroom, trying to determine the edges of a potentially mammoth hole.
Workers using "deep soil probes" gingerly tested the ground around the home in Seffner, Fla., about 15 miles east of Tampa, looking for steady ground, said Jessica Damico, a spokeswoman with Hillsborough County Fire Rescue, which is leading the operation. The sinkhole could stretch to as much as 100 feet across directly beneath the surface and plummet up to 60 feet deep into the earth, she said.
Teams of rescue and emergency management workers - more accustomed to tackling destruction from hurricanes and other natural disasters - were trying to determine how best to proceed with the deadly sinkhole, Damico said. Sinkholes are common in Florida, but it's rare when one opens up under a home and takes a person with it, she said.
"I can't think of anywhere in the country where this has happened before," Damico said. "This is very unique."
STORY: Sinkholes are common in Fla. but rarely cause death
Jeff Bush, 37, was in his bedroom in the one-story home on Faithview Drive at about 11 p.m. Thursday when the sinkhole yawned directly under him, taking him, his bed and the rest of his bedroom furniture as well, Damico said.
His brother jumped into the hole to try to save Bush but had to be rescued himself by a sheriff's deputy. Five other residents, including a small child, made it out of the home unharmed, Damico said. Bush could not be rescued and is presumed dead. Workers cannot recover the body until the ground is deemed safe enough to support heavy equipment, she said.
"We're at a standstill there," Damico said.
Two adjoining houses - one on either side of Bush's - were evacuated by rescue workers. Red Cross officials on the scene are working to place those residents in temporary housing, she said.
The opening to the sinkhole in the home is about 20 feet across but could be five times that wide directly beneath the ground, Damico said. The sinkhole also appears to be 15 feet deep inside but could be up to four times that deep, she said.
"Think of it as an hourglass," Damico said. "You have an opening then a wider part directly beneath it."
Florida is highly prone to sinkholes because there are caverns below ground of limestone, a porous rock that easily dissolves in water.
"You can almost envision a piece of Swiss cheese," said Taylor Yarkosky, a sinkhole expert from Brooksville, Fla. "Any house in Florida could be in that same situation."
A sinkhole near Orlando grew to 400 feet across in 1981 and devoured five sports cars, most of two businesses, a three-bedroom house and the deep end of an Olympic-size swimming pool.
More than 500 sinkholes have been reported in Hillsborough County alone since the government started keeping track in 1954, according to the state's environmental agency.
On Saturday, engineers from local firm Bracken Engineering used hydraulic drills to probe the ground around the Seffner home, Damico said. Workers initially used radar to try to determine the ground's density but switched to the more sophisticated hydraulic probes, she said. So far, they're finding a spreading sinkhole that could potentially swallow more homes.
"The ground is extremely unstable," she said.
Contributing: Associated Press
Rick Jervis, USA TODAY