TALLAHASSEE, Fla. (AP) - State geologists already have been to 30 sites and mapped about 50 sinkholes as they begin to plumb the depth of the state's vulnerability to ground collapse.
    
The Tampa Tribune (http://bit.ly/1fKcUJ0) reports that Florida received a $1.08 million federal grant for a three-year statewide study, starting last month with a pilot study in Columbia, Hamilton and Suwannee counties.
    
The result will be a detailed, multi-layered map that shows where sinkholes are most likely to form, but doesn't predict where and when individual sinkholes will occur.
    
In February, a Seffner man died when a sinkhole opened under his bedroom as he slept.
    
Sinkholes are common in Florida because of porous rock, such as limestone, that stores water underground.
    
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Information from: The Tampa (Fla.) Tribune, http://www.tampatrib.com

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