So, who is responsible for mitigating this soil vapor intrusion? The New York State Department of Environmental Conservation (DEC) describes the conditions under which the state will conduct the vapor intrusion evaluations and the order in which the sites will be assessed. If exposures represent a concern due to indoor sources, then the state will provide guidance to the property owner and/or tenant on ways to reduce their exposure. If exposures represent a concern due to outdoor sources, then DEC will decide who is responsible for further investigation and any necessary remediation. Depending upon the outdoor source, this responsibility may or may not fall upon the party conducting the soil vapor intrusion investigation.
Pollen, dust, fungi, industrial pollutants, and general vehicle exhaust are common outdoor sources of indoor air pollution. Other sources include exhaust from vehicles on nearby roads or in parking lots or garages, loading docks, odors from dumpsters, unsanitary debris near outdoor air intakes, and cigarette smoke from office workers now required in most cities to take their cigarette breaks outside of building entrances. Another source is exhaust from the building itself or from neighboring buildings that is re-entrained, or drawn back into the building.