In East Haven, as planes from Tweed New Haven Regional Airport flew overhead a Morgan Avenue residence recently, a device about the size of a mini-fridge measured ultrafine particles emitted during takeoff.

Inside the house, situated roughly two miles from the airport, a slightly smaller instrument sampled indoor air quality. Both machines fed data into an Apple MacBook laptop running a program that generated charts and graphs.

"We’re essentially monitoring them — ensuring they remain plugged in and functioning correctly," explained Gretl Gallicchio, a board member of 10,000 Hawks, an environmental group based in New Haven.

Dana Walker, another member of 10,000 Hawks and owner of the Morgan Avenue home, planned to host the instruments for at least two more days. Afterward, the setup would be relocated, likely to another home within a specified radius of the airport.

This effort is part of a newly launched project by 10,000 Hawks aimed at assessing how the airport's operations impact surrounding air quality. The group hopes this study will offer a clearer, more transparent view of Tweed's environmental footprint and contribute to decisions regarding the airport's potential expansion.

"In terms of public awareness, our goal is to help people truly grasp the implications of an expansion," said Gallicchio, who leads the project.

Over the past six weeks, project members have deployed advanced sensors at more than a dozen locations around Tweed’s airfield, extending as far as Short Beach in Branford. Valued at approximately $100,000 collectively, these sensors are designed to measure the size and concentration of particulate matter — also known as particle pollution — emitted by aircraft engines at the airport. Both indoor and outdoor samples have been collected, with data collection slated to continue for another week.

According to the Federal Aviation Administration (FAA), aircraft emissions include the same pollutants as automobiles, but jet fuel combustion produces much smaller particles than those emitted by cars, explained Walker. The project's sensors, which can detect particle size, will differentiate airport-related pollutants from those generated by highway traffic.

"That’s why we opted for this type of monitoring," Walker noted. "It distinguishes this air pollution from all other sources because these extremely tiny particles are specific to jet fuel combustion."

Project members indicated their study is partly a response to the Environmental Assessment (EA) for the proposed airport expansion. Published in March, the 206-page EA concluded that extending Tweed's runway and constructing a new terminal on the East Haven side would actually improve the airport's environmental impact. The assessment was conducted by McFarland Johnson, a national aviation consulting firm.

Gallicchio emphasized the importance of accurate measurements of Tweed’s current air emissions to enable responsible decision-making regarding expansion.

In March, 10,000 Hawks received a $10,000 grant from the Greater New Haven Green Fund for its air pollution study. However, Gallicchio noted that they quickly realized this amount was insufficient to generate scientifically defensible data.

To bolster their study, 10,000 Hawks partnered with Neelakshi Hudda, an environmental engineering professor at Tufts University specializing in studies of toxic air pollutants at major airports such as Los Angeles International Airport and Logan International. In addition to providing Tufts' advanced air testing equipment, Hudda and her graduate students assisted in collecting data around the airport and analyzing results at their Boston campus laboratory.

A few weeks ago, Hudda and her team conducted initial air quality measurements using an electric vehicle transformed into a mobile lab with various monitors and devices. Stationed on Uriah Street in East Haven, just 25 yards from the airport's runway, the Tufts Air Pollution Lab (TAPL) monitored nanoscopic particles, as well as nitrous oxide, carbon dioxide, and black carbon, according to Gallicchio.

"As soon as the plane engines reached full thrust, the particle readings soared to their maximum levels," Gallicchio reported.

Project members also aim to raise awareness among residents living farther from the airport, where the noise from flights is less disruptive but air pollutants likely still affect health, noted Hudda.

In a 2014 study, Hudda and colleagues used a mobile lab to monitor air quality across a wide area near LAX. They found particle concentrations about four to five times higher in areas five to six miles from the airport compared to unaffected areas. Even at distances of about 10 miles, particle concentrations were at least twice as high.

"We want to educate those who are further from the most intense noise about the impact they’re still facing because pollutants are reaching them daily," Gallicchio emphasized.

According to a news release from 10,000 Hawks, the air quality project’s data, analysis, and conclusions will be shared in a final report with local communities, public health officials, medical providers, local and state government officials and agencies, and academic institutions, among others.

Project members hope their comprehensive efforts will prompt New Haven Mayor Justin Elicker and the city's Board of Alders to request a full Environmental Impact Statement (EIS) regarding the airport's proposed expansion.

Tweed's proposed expansion project includes extending the runway from 5,600 feet to 6,635 feet, constructing a new 70,000-square-foot terminal on the East Haven side of the airport, and establishing a new airport entrance off Proto Drive in East Haven, accessible via Hemingway and Coe Avenues, officials have outlined.