Hillsborough County is part of an area known as "sinkhole alley" that accounts for two-thirds of the sinkhole-related insurance claims in the state, according to a Florida state Senate Insurance and Banking Committee report.

But Mike Merrill, county administrator for Hillsborough County, stressed Friday that the sinkhole in question was not "your typical sinkhole."

"They still have not been able to find the boundaries of the underground chasm. For that reason, we're being very deliberate, he said. "We're very frustrated. But we're pursuing it as quickly as we can, as safely as we can."