TAMPA - For those in the demolition business, an old house can be a Pandora's box.
Crews approach each house knowing mostly what they can see on the outside. Once they start taking the structure apart, things can quickly get messy.
"You've always got unforeseen things - things that ain't covered under the contract," said Tom Hull, project supervisor with Johnson Excavation Services Inc., the Plant City company that the city of Tampa hired in January as its on-call demolition contractor.
There might be tires buried in the backyard or a long-forgotten septic tank waiting under the grass. In Sulphur Springs, one of Tampa's oldest neighborhoods, Johnson Excavation crews earlier this year unearthed a hidden Prohibition-era cellar used for hiding bootleg liquor.
Many of the surprises can be expensive, adding thousands of dollars to the cost of tearing down the house.
That happened to Johnson Excavation, which tore down more than two dozen houses around the city before withdrawing from its 12-month contract in mid-May. The city's reluctance to pay for additional, unexpected costs made the contract no longer worth it, company officials said.
The city has hired Wimauma-based Magnum Demolition to pick up where Johnson left off.
Magnum's $330,000 contract includes payment for work through the end of September, then additional work through the end of Johnson's original contract in January 2014. Both Johnson and Magnum are first-time contractors with the city of Tampa.
In a city like Tampa, unusual demolitions are common, said Jake Slater, the city's code enforcement director.
"This is not regular demolition," Slater said. "We find things: septic tanks, fish tanks, an underground bunker."
An underground bunker?
"It looked like it was from back in the World War II era," Slater said.
Johnson Excavation president Don Johnson said his company originally bid $200,000 to do 25 demolitions. The city tripled that number when Mayor Bob Buckhorn unveiled his Nehemiah Project in January, with the goal of demolishing 51 derelict houses in Sulphur Springs.
Nehemiah later expanded to 86 homes and stretched north to Bougainvillea Avenue.
Johnson completed 11 demolitions in Sulphur Springs. Company officials said the complicated nature of some demolitions slowed the project to a crawl.
The trouble started with the first house - the one Buckhorn took a ceremonial swipe at with an excavator on Jan. 29. As demolition crews moved into the property, they found tires buried in the yard and asbestos in the building. They also had to take down a dead tree standing in the yard. Those problems added about $1,000 to the cost of the job, Johnson said.
Another Sulphur Springs house turned out to have three layers of siding, one laid on top of the other over the years. The bottom layer was asbestos shingles, a common feature on homes built in the 1930s and 1940s. Disposing of the toxic shingles took extra time and money.
Elsewhere, Johnson crews tearing down a house on Alicia Street near Lowry Park discovered the neighbor's sewer line was tied into the one they had just capped. They found that out after the neighbor called the city to complain that her sewer was backing up. Johnson had to pay to fix it.
"These unforeseens, a lot of them, they're found on the job when you're there," Johnson said. Stopping work to sort them out can cost hundreds of dollars an hour in idle men and machinery, he said.
Johnson officials say they got paid for some of those extras early on in their contract. But they said those payments stopped after Buckhorn reorganized the Clean City and Code Enforcement divisions and city officials started looking more closely at costs.
Slater said Johnson was being held to the terms of its contract.
Magnum's president, John Varranti, declined to discuss his contract with the city.
He said, though, that he has run into few problems like the ones Johnson Excavation says it found in Sulphur Springs and elsewhere.
"Your typical residential usually isn't that bad," Varranti said. "The main thing is what the people leave behind. Sometimes you go into a house that's just full of personal belongings."