Rotten Egg Odor From Construction Site Explained

Walking outside during the last few weeks, many students have been asking, “What’s that awful smell?” It was clearly emanating from the One Western Avenue construction site. Was it a gas leak or some accident? The answer is no. It is a by-product of the site excavations, caused by the disturbance of a 10-foot layer of peat deep within the ground.
The cause of the odor is the organic matter in the peat reacting with the open air, a Harvard Planning and Real Estate (HPRE) official says. The naturally-occuring chemical hydrogen sulfide (H2S for you chemistry buffs) is the result of the reaction. Hydrogen sulfide, even in minute quantities (as low as 2 parts per billion), can be detected by the human sense of smell.

The smell has drifted into the open windows of SFP apartments and even across the river to the apartments in Peabody Terrace, whose open windows are the units’ only sources of ventilation.

While they realize that the officials and contractors are powerless to stop the smell, SFP residents are still frustrated.

“The smell is absolutely disgusting and nauseating,” said Brijesh Jeevarathnam (OH). “HPRE assures me that the gas is non-toxic and totally safe but that doesn’t make me feel any better. It seeps into the apartment and it is even worse outside. We keep the AC running sometimes just to ward the smell off. But, I guess there is really nothing they can do about it.”

HPRE has tried to rectify the situation for SFP residents. Additional air filters have been placed on their air conditioners and plug-in air fresheners are being offered at the SFP office. In addition, Karen Powers of Harvard’s Deparment of Environmental Health and Safety says that construction workers are applying odor-suppressant foam to the soil at the source to limit the smell.

“We knew we might have an issue during construction, but to do construction in that area, you just have to deal with it,” she said.
After noticing the problem, Powers checked with other building sites. The same phenomenon was detected at a recent MIT construction project as well as at a local hospital’s building site. No smell has been detected during the construction of Hawes Hall or the Spangler Center, however.
To ensure that the level of hydrogen sulfide emissions remain in the minimal range expected, Jonathan Lavash, HPRE Senior Project Manger for One Western Avenue, explained that “during all excavations, a certified industrial hygeniest is present, doing real-time air monitoring to ensure there are no safety issues.”

Despite their best efforts, Powers says the estimates the odors will continue for approximately six weeks.