Residents in Westwood and elsewhere may have been excited to ring in 2012 the night before New Year's Eve, but that night also marked the beginning of a Hazmat situation on High Street.

While filling up the fuel pumps at Westwood Mobil, a significant quantity of gas was spilled during the operation on Dec. 30, Westwood Fire Chief William Scoble said Monday.

But it was days later, on Monday, Jan. 2, when Westwood safety officials responded to the area. The response time was not due to a delay on the part of public safety, but rather because nothing suspicious had been reported until that following Monday.

It was around 4 p.m. that day when tenants at the Coldwell Banker building, which lies adjacent to Westwood Mobil, reported an odor of gas in the building.

The Westwood Fire Department responded to the area and found that gas odors were beyond a normal and safe level inside, and as such evacuated the the employees and tenants of the building.

Upon further investigation, the fumes had been the result of the spilled fuel, which had, by then, seeped into the soil in and around the property near the two buildings, as well as an adjacent residence on Gay Street.

"Upon questioning, the company admitted to a small spill," Scoble said. But the company, he added, reported a spill of less than 10 gallons. After investigating further, officials discovered more than 10 gallons had been spilled.

Due to the quantity of fuel spilled and the incident involving the soil removal, the Massachusetts Department of Environmental Protection has now become involved, said Scoble, who, as of Monday, had not yet received the official report number from the DEP on the incident.

Gas odor levels at the Coldwell Banker building, meanwhile, were quickly returned to normal and the tenants of the building have been able to return safely.

"They were evacuated for a while," Scoble said. "They are now back in. The levels are way below the threshold (of dangerous). It is being monitored constantly."

The matter continues to be investigated and a contractor has been hired to remove the contaminated soil using a recovery well; the soil, which is to be classified as Hazmat material, will then be properly disposed of.

"They're removing as much as they can," Scoble said.