Germantown firefighters and Memphis Light, Gas & Water Division believe soil saturated by rain caused multiple methane gas leaks bubbling through cracks and breaks in the asphalt on Wolf Trail Cove at Germantown Road Thursday.
Germantown police evacuated close to 70 people from the office building at 7796 Wolf Trail Cove and seven adjacent businesses, including Waffle House and Las Tortugas Deli Mexicana at 1215 S. Germantown Road.
They were kept out of the buildings as officials waited for air levels to return to normal. Besides being flammable, the methane forced oxygen out of buildings, making it difficult to breathe, Germantown Fire Chief John Selberg said.
The gas levels were high enough to be flammable. When the rain stopped briefly, around 4 p.m., the readings dropped, likely because the methane could dissipate in the drier air, Selberg said.
For several hours, authorities including engineers from MLGW did not know if the leaks were methane or natural gas.
“Methane is little better because it is not as flammable. But the problem with it is, I can’t shut this off,” Selberg said.
Pepe Magallanes, who owns Las Tortugas, rushed to the scene when the store manager called him at 2:15 p.m., saying police were evacuating the restaurant.
“We just want to know when we can get back in and clean up,” he said, waiting anxiously near a line of firetrucks idling along Germantown Road.
The cove sits over an old landfill. It is equipped with ventilating equipment to allow gas from the decaying debris to escape. Authorities believe the rain concentrated the gas in the soil, forcing it out at toxic levels. Leaks were bubbling up in foamlike swirls across the cove, in cracks in floors and in the nearby Wolf River.
At the back of the cove, gas readings were low enough that guests and workers at Holiday Inn Express did not have to evacuate, although they were confined to the building.
By about 4 p.m., the methane levels had abated enough in open areas that police allowed hotel guests to start their cars and leave.
The first call came from workers in the office building, complaining of the smell and nausea.
When police and firemen responded, they found numerous leaks across the area.