LAND O'LAKES — Terence Doohen said he understands the risks that come with living in a part of Florida sometimes called Sinkhole Alley.But nothing prepared him for what happened Friday, when the earth gave way under two of his neighbors' homes, one just down from his own on Ocean Pines Drive."It's just one of those events that, we all see them on TV, and it's like, you really feel bad for those people that are there," Doohen said. "And then it's happening right in front of your eyes."Pasco County authorities say one of the largest sinkholes in decades — and perhaps the biggest in more than a half century — had stopped growing by Saturday morning. But they were continuing to monitor the roughly 225-foot-wide expanse for signs of more trouble.The sinkhole claimed the two homes early Friday morning in the Lake Padgett Estates neighborhood and damaged part of a third. The people who lived in them had either already left for work or managed to escape before the homes gave way.County officials deemed at least eight others homes, including Doohen's, unsafe for occupancy until experts can conduct further analysis.Geologists from the Department of Environmental Protection will determine when the sinkhole has permanently stopped expanding, said assistant county administrator for public safety Kevin Guthrie. He was unsure when that would be, but said the department likely will err on the side of caution due to the sinkhole's considerable size.County officials will continue to monitor the site every few hours in the coming days. Emergency crews were on hand Saturday to help residents as they sought to remove important possessions from threatened homes.Doohen was among those being helped by sheriff's deputies. He took enough items to last for the next three to five days, including food that would spoil in the refrigerator and tools for his lawn and landscaping business.He described how the sound of the sinkhole expanding the day before created an eerie backdrop as the ground collapsed."It's creaking, it's splashing, wood breaking, ripping," Doohen said. "You know, sounds that just are not normal in our daily lives that you're not used to hearing, unless you're in the construction business."Aerial footage of the sinkhole showed parts of a roof, chimney and satellite dish partly submerged in the water. Halloween and Christmas decorations were visible in a bin floating on the layer of dirt that had settled on top of the water. A mattress floated nearby, surrounded by pieces of furniture.Until officials tell him his house is safe, Doohen and his family — wife, Tisha, son Isaac and their two cats — are moving in with a neighbor three houses down. Authorities told him it could be up to a week before he gets word.Sinkholes are ordinary in this part of Florida, in the way that tornadoes are a familiar threat to people in the Plains states or that earthquakes send tremors along the West Coast. They are particularly common in Central Florida, including in Pasco, Hernando, Hillsborough and northern Pinellas counties.Friday's sinkhole was Pasco's largest in at least three decades, Guthrie said. Residents who had lived in the area for 50 and 60 years told him they had never seen one of this magnitude.Sinkholes form when underlying bedrock limestone is eroded by water, causing it to collapse and pull everything above down with it.Though Friday's sinkhole had stopped expanding, it carries with it other risks. The chemicals that leaked out of septic tanks from the affected homes, for instance, could still pose a threat to neighbors.Ann Tihansky, a physical scientist for the U.S. Geological Survey, has studied sinkholes in southwest Florida. She said her concerns include debris that could contaminate groundwater.In a 1999 study, Tihansky revealed the link between sinkholes and underlying aquifer systems that supply much of Florida's drinking water, underscoring the importance of preventing contaminants from draining into them.Pasco County spokesman Doug Tobin said he was unaware of any risk of chemicals leaking into nearby groundwater. The county wouldcall in a hazardous materials team to extract any contaminants. But Tobin said the Florida Department of Environmental Protection had instructed them to avoid touching the sinkhole for a few days."You have to weigh public safety versus damaging the sinkhole further," Tobin said.Before it stopped expanding, the hole appeared at risk of spreading to Lake Saxon, located near to the affected homes."The fact that it's so close to the lake makes me think it's possible to be part of a bigger structure, geologically," Tihansky said. "I would be on alert if I were a homeowner in the region."Though the sinkhole created irreparable damage, Doohen said the incident could have been much worse. The residents of 21835 Ocean Pines Drive, the first house to go down, had left their home for work about 6:45 a.m., he said.Pasco County Fire Rescue crews were called to the scene at 7:21 a.m."Let's just think if it's a Saturday instead of a Friday," Doohen said. "If it's Saturday morning and it's 7:30, 7:15, guess what: They're probably not at work."Times news researcher Caryn Baird and staff writer Colleen Wright contributed to this report. Contact Jasper Scherer at [email protected] Follow @jaspscherer.