Construction crews renovating the future home of Harvard Student Agencies (HSA) cut into a gas pipe yesterday afternoon, forcing an evacuation of the building.

Workers in the basement of the recently-christened Burke-McCoy Hall began to smell gas around 2:35 p.m. after they cut into a "charged" pipe they were told was empty, said Ken Trecartin, the construction superintendent.

Two Cambridge fire trucks and one ambulance were called to the scene.

"All the workers had been evacuated when we arrived, and there had already been a temporary patch put on the line," said Cambridge Deputy Fire Chief John O'Donoughue. "[Commonwealth Gas] put a more permanent patch on, and then cut off the gas at the main."

The building will house HSA's main offices at the end of November.

The gas dissipated quickly from the gutted building, but O'Donoughue said ignition of the leak in its early stages could have caused "significant" damage to HSA's $1.4 million facility.

"I mean there would have been damage," O'Donoughue said. "You can't tell for sure until it happens, but with a gas leak in a construction environment, there's always danger."

According to HSA General Manager Richard M. Olken '67, the construction workers were cutting the correct pipe when the leak occurred, but a Commonwealth Gas employee, sent to disconnect the building's gas before construction began in that area, had shut off the wrong valve.

"I got a call from the construction chief about 3 because he needed to confirm absolutely that we had gotten the gas company to say 'It's our problem,'" Olken said. "There are two pipes feeding in, one that we just put in and one older one, and the new pipe was incorrectly shut off."

Firefighters at the scene found no evidence that dangerous gas levels persisted in the building, and workers were allowed back in around 3:10 p.m.

This incident is not the first glitch in the renovation of the building, which previously housed the Mather Hall School. Other problems have included the discovery of lead paint and small amounts of asbestos, Olken said.

HSA Vice President Adam J. Rymer '97 said that many of the building's problems are due to its age, but current renovations, which include the addition of an elevator and increased handicapped access, will modernize the facility significantly.

"This is really no big deal," Rymer said as he was surveying the scene. "We're still going to open on time.