Aerial view of the Sprague Energy tank farm in South Portland in 2013. FILE

SOUTH PORTLAND — There are elevated levels of toxic chemicals in the air in parts of South Portland, but officials need to collect more data to be sure it’s being caused by above-ground petroleum storage tanks in the city.

That’s the key finding of the city’s Clean Air Advisory Committee, presented along with the committee’s recommendations at a city council workshop March 2. The council took no action, but does plan to address the committee’s recommendations at a future meeting.

“It’s crucial for us to get this under control,” Councilor April Caricchio said.

The group’s recommendations focused on having the city pressure the state Department of Environmental Protection (DEP) to take stronger regulatory action. The committee also suggested the city consider requiring the companies that own the tank farms to install vapor capture systems if further study proves the tank farms are the source of the toxins.

The council commissioned the committee, led by Facilitator David Plumb, in September 2019 after the federal Environmental Protection Agency (EPA) revealed that Global Partners, LLC, which operates several above-ground oil storage tanks, had violated the Clean Air Act. Later, the city learned there were also emission issues with the Sprague Energy tanks. The tanks are located near the city’s Ligonia neighborhood, east of Route 1 and north of Billy Vachon Street.

The committee’s findings are based in part on data from six local monitoring stations installed by the DEP in 2019 that gathered air samples and analyzed them for chemical compounds.

The most notable result, Plumb said this week, was the level of the chemical naphthaline. The committee cited data from a December 2020 report, prepared by the U.S. Centers for Disease Control and Prevention and based on data from the DEP monitoring stations recorded from July to October 2020. The report measured the levels against the Ambient Air Guideline (AAG), a benchmark set both by EPA and DEP.

According to Plumb, the report shows levels were above the AAG benchmark at four monitoring stations in South Portland: the assessor’s office at 41 Thomas St., Bug Light Park, South Portland High School and the Redbank Community Center at 95 Macarthur Circle. The elevated levels could mean a potential long-term elevated cancer risk, Plumb said.

“The cumulative naphthalene averages at South Portland stations were 1.1 to 2.7 times higher than the AAG,” the report’s authors wrote.

While the tanks could be the source, Plumb said, the data does not conclusively prove that. To be sure, he said, the DEP needs to move the stations at at the assessor’s office, the high school, the community center and another at the school administration building. The committee’s recommended moves seem small, ranging from 0.6 to 1.6 miles, but that’s enough to help the city and DEP pinpoint the source of the toxins, Plumb said.

“It can be a relatively significant move in terms of air quality,” he said.

The committee also strongly recommended the city ask DEP to install more monitoring stations along the tank farms’ fenceline, which would give even more accurate readings, Plumb said.

At Tuesday’s meeting, committee member Brie Hicknell underscored the need to get more data before drawing any definitive conclusions.

“It’s hard to recommend a solution to a problem that we don’t fully understand,” she said.

Public comments chimed in with the committee’s recommendations, and one person, Bob Klotz, who did not specify if or where he lived in the city, expressed frustration at the slow process.

“I can’t believe we’re still talking about this,” he said. “It still seems absurd to me that we don’t have monitoring stations close to the tanks.”

Chaya Caron, who lives at 49 Chapel St., said she can smell emissions from the tanks and encouraged the city to take action on its own – whether the state is involved or not.

“If we were able to come up with our own plan around the tank farms and these businesses that want to come into our zip code that is separate from the EPA, is separate from the state, where we specify this is how we want to do business with these businesses, I think we could really set a standard for the whole nation,” Caron said.

The commission recommended the city urge the DEP to change regulations regarding tank emissions to include regulating of odors, as well as accounting for cumulative health effects. Right now, Plumb said, the rules focus on a single tank, not necessarily the effect that multiple tanks have when they are next to each other.

Overall, Plumb said, the city should work with state regulators instead of trying to regulate the tank farms locally, citing an ongoing lawsuit between the Portland Pipeline Co. and the city over a local ordinance as an example of the potential consequences.

“It’s a harder road for the city to enforce its own regulations,” he said.

All the councilors said they supported the committee’s recommendations. Councilor Katelyn Bruzgo addressed local frustration and asked for patience while the council gathers more information on the problem.

“Truly, we haven’t been doing this, actually, for that long,” she said. “This is a very involved, complicated issue, and a lot of times when you’re approaching these things and it’s new, and it’s new in our community, trying to figure this out we need that data to make the right decisions and be able to get done what we need to get done.”

The meeting marked the official end of the committee’s work, but all councilors also agreed to address creating a permanent version of the committee to continue advising the city on air quality issues.

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