SOUTH PORTLAND — Local air quality issues have been in the news lately as the Environmental Protection Agency finalized a lawsuit settlement with Global Partners for air emission violations of volatile organic compounds at their South Portland terminal. The Maine Department of Environmental Protection permitted allowable air emissions of 633 tons a year of volatile organic compounds from six petroleum terminals across South Portland. Global Partners’ South Portland terminal is one of the smaller of these terminals, but they may typify air quality issues facing Portland and South Portland.

For years, the DEP did not even consider or try to track bulk storage tanks’ volatile organic compound emissions. The DEP allows bulk petroleum storage terminals to self-report their estimated emissions. Global reported no tank emissions up to 2011; only after the EPA required Global to conduct emission tests in 2012 did Global begin to report tank emissions.

Global’s emissions may be particularly problematic as they heat their heavy petroleum fuels and asphalt for transfer and conditioning. Asphalt is heated to over 300 degrees Fahrenheit and aerated to help mix additives. The aeration is so strong that an oil mist was observed spewing out the top of the tank during the 2012 testing. Global plans to use mist eliminators to control emissions, yet mist eliminators are a liquid removal process and will not control emissions.

Last summer the DEP and the city of South Portland initiated a citywide ambient air quality testing program. Four stationary monitoring stations were installed throughout the city to collect samples, and individual air sampling canisters were distributed to residents to collect a sample when they smelled petroleum odors.

This air monitoring program raises some questions. Why weren’t there already ambient air monitoring stations in South Portland, like there are in Portland and Cape Elizabeth? How could the DEP allow significant volatile organic compound air discharges from the major petroleum terminals without knowing the ambient air quality in South Portland and how additional discharges would affect it? Did the DEP consider established ambient and residential air quality standards that are protective of human health? If the DEP did not determine allowable discharge limits based on protection of human health, what did they base them on?

The DEP described the initial results of the ambient air monitoring as inconclusive, but the summer winds blow mostly from south to north in the summer (toward Portland) and low volatile organic compound levels in South Portland air could be expected.

A second release of data came Oct. 16 from the DEP and shows that South Portland has significantly and consistently higher ambient levels of volatile organic compounds than Portland. In addition, significantly higher levels of volatile organic compounds are detected in the areas adjacent to several bulk petroleum storage terminals, including Global’s terminal.

Data on the direct monitoring of the terminal’s emissions need to be collected and evaluated to determine if the emissions from the petroleum terminals affect adjacent ambient air quality. The DEP and/or Maine Center for Disease Control and Prevention toxicologists need to determine what is acceptable air quality protective of human health in the residential areas and use that standard to establish an acceptable amount of discharge from the petroleum storage terminals.

Are South Portland and Portland residential areas near the waterfront healthy places to live, and should I continue to live and raise my kids here? My house and the city of South Portland pre-date the petroleum terminals, and I choose to live in South Portland because I want to live in the city, have a short commute, live in a modest older home and try to lead a less carbon-intensive lifestyle. But if city living negatively affects one’s health, and if South Portland is treated as Maine’s gas station and volatile organic compound emissions from major sources continue to be uncontrolled, then perhaps no one should be living in South Portland.

The time of uncontrolled industrial discharges of pollutants to water and land is over, and it should be over for air now also. Clean air is a community resource, and it should not be allowed to be soiled by a select few. The DEP needs to take a stand on this and protect the people of Maine.