The Passyunk Soil Gas Site is located in the Pointe Breeze section of South Philadelphia. It is a residential neighborhood bounded by the Philadelphia Gas Works (PGW) Passyunk facility on the west, the Sunoco Refinery to the south, and the Schuylkill Expressway to the East/Northeast. The neighborhood is residential with a local tavern, a playground and a mummer’s hall. There are no daycares or schools. PGW recently completed an environmental investigation of its facility which included an off-site soil vapor study in the Passyunk residential neighborhood. The Pennsylvania Department of Environmental Protection (PADEP) oversaw this investigation. PGW detected elevated levels of chloroform in the soil vapor within the residential neighborhood at levels above standards established by the PADEP. The Agency for Toxics Substances and Disease Registry (ATSDR) assisted the Pennsylvania Department of Health with the review and evaluation of PGW’s soil vapor data. ATSDR referred the site to EPA’s removal program. State and federal officials agree that further investigation of the chloroform and the potential for vapor intrusion is warranted in the local area. Since chloroform is unrelated to PGWs operations, the United States Environmental Protection Agency, (EPA) will be conducting the follow-up vapor intrusion investigation under the authority of the federal “Superfund” law (more formally called the Comprehensive Environmental Response, Compensation, and Liability Act.
Chloroform is a volatile organic compound (VOCs). VOCs evaporate easily at room temperature and these vapors may move through the soil. When these vapors concentrate beneath the foundation of overlying buildings, the contaminated vapors can seep into the indoor air of the building through cracks and conduits in the house foundation. This process is called vapor intrusion.
