APOLLO BEACH — Two people were killed and four people were seriously injured Thursday in what is being described as a "major incident'' at the Tampa Electric Company power plant in Apollo Beach.
Hillsborough County Fire Rescue units responded to a 911 call about a possible explosion at the Big Bend Power Station at approximately 4:20 p.m.
Four people were transferred to Tampa General Hospital, spokeswoman Ellen Fiss said. Two were transported by ground and two by air. None of the six casualties were identified as of Thursday evening, but all have life-threatening injuries.
The two deaths were pronounced at the scene.
Victims sustained burn injuries as well as other injuries that "would be categorized as very severe," said Fire Rescue spokesman Corey Dierdorff.
The incident occurred in Unit 2, the second coal-fired generating unit of four at the plant. It appeared to occur near a slag tank, where coal by-product falls after it is burned, said TECO spokeswoman Cherie Jacobs. Hazardous material units were deployed to the scene.
TECO workers were conducting routine maintenance on the slag tank at the time, Jacobs said. The company is working with investigators to determine the cause of the incident.
The unit was shut down Thursday afternoon, though two other units continued to run. There were no power outages connected to the incident.
Jacobs said TECO was making resources available for its employees in the aftermath of the tragedy.
"Tampa Electric is full of long-term employees and we have long been a family," she said. "The Tampa Electric family right now is mourning."
Hot slag is a molten by-product created when coal is burned for electricity. Chunks of it fall into cooling tanks and the remnants, which are black and glass-like, are recycled and used in sand blasting and roofing.
Twenty years ago almost to the day, four TECO workers were seriously injured during routine maintenance of a slag tank at a plant in Port Sutton. Two of the injured workers sustained first- and second- degree burns in the June 1997 incident.
TECO's Apollo Beach power plant, located off Big Bend Road, opened in 1970 off the Hillsborough County coast. Unit 2 went online in 1973, according to TECO's website.
Smoke from its towering stacks can be seen from around Tampa Bay. The plant primarily burns coal. However, it has in recent years added natural gas- and oil-fired capabilities.
The plant also is a popular tourism destination for its manatee viewing center.
The Occupational Safety and Health Administration has an open safety case pending at TECO's Big Bend plant from May 24. No details were available late Thursday.
In 2010, a TECO lineman died from electric shock after making contact with a power line, according to an Occupational Safety and Health Administration report. The company paid a $6,300 fine.
The same year TECO paid a $5,250 fine for a serious electrical safety violation at a facility on MacDill Air Force Base.