|
Robertson was determined to use these more sophisticated tools to bolster pollution monitoring around Lake Charles, where industrial facilities have a history of violating air quality laws and exceeding emissions limits. Over the last 10 years, three major emitters in the area — Citgo Petroleum, Sasol Chemicals and Westlake Chemicals — have faced nearly 40 enforcement actions from state and federal regulators and paid a combined $3.2 million in fines, according to EPA compliance data.
Using the federally funded AQSync monitors along with the PurpleAir sensors, Robertson hoped to produce enough evidence of harmful pollution to force corrective action from the Louisiana Department of Environmental Quality, the agency tasked with managing air quality in the state.
But that hasn't happened.
Grassroots air monitoring data has yet to spur any LDEQ investigations in Louisiana, and the state has passed legislation limiting what communities can do with their pollution measurements. At the same time, the Trump administration has delayed Biden-era rules for dozens of chemical plants required to track carcinogens around their boundaries.
These setbacks have been dispiriting for Roberston, who insists that LDEQ's air quality metrics for Southwest Louisiana do not reflect the lived experiences of its residents.
"If you live in the area, you know that there's a problem," she said. "It's just that the powers that be refuse to acknowledge that there's a problem."
Conflicting Messages
Air quality in the U.S. is regulated under the Clean Air Act, which requires states to track six common pollutants to ensure they remain at levels deemed safe by the EPA. These ambient air pollutants — ozone, particulate matter, carbon monoxide, sulfur dioxide, lead and nitrogen dioxide — are known as criteria pollutants.
The Clean Air Act also regulates 188 distinct hazardous air pollutants, or air toxics, which are known to cause cancer and other serious health effects. Facilities must track any air toxics emitted as part of their operations, though monitoring is often limited to analyzing air samples from exhaust stacks about once a year — a process known as stack testing. Plants use these stack tests to extrapolate their toxic emissions for the rest of the year, and regulatory agencies generally accept the estimates unless a facility reports some form of noncompliance.
Regulators and plant operators are not required to test air quality in communities downwind of the facilities, where people like Robertson live.
As a result of this system, neither regulatory agencies nor communities around industrial sites know what's coming out of the facilities on any given day, explained Adam Kron, a senior attorney at the environmental law group Earthjustice.
"You basically have this unfortunate blind spot where [industrial facilities] might be in full compliance, according to what's on paper and according to the law," he said. "That doesn't address the fact that the community is breathing in more [toxic pollutants] than they should be."
In April 2024, the Biden administration finalized the so-called HON rule, a Clean Air Act update designed to slash harmful emissions at over 200 chemical plants.
The EPA regulation calls for many of these facilities to monitor six carcinogenic air toxics around their fencelines. A similar monitoring requirement imposed on oil refineries a decade ago has proven "very effective" at reducing toxic releases and capturing fugitive emissions that facilities often miss, explained Michael Koerber, the former deputy director at the EPA's Office of Air Quality Planning and Standards.
The HON rule's fenceline monitoring requirements are set to kick in later this year, giving people near the plants the clearest picture yet of local air quality.
"The fenceline data allows the neighboring communities to understand what is in the air that they're breathing," Koerber said. The findings are also "a chance for the facilities to undertake some housekeeping and to determine how they can best manage these emissions."
Besides pushing for greater transparency around facility emissions, Biden's EPA sought to arm neighboring communities with tools to conduct their own probes into local air quality. In 2022, the agency earmarked more than $50 million in American Rescue Plan and Inflation Reduction Act funds for community air monitoring projects, aiming to capitalize on a boom in commercial sensors like Robertson's PurpleAir and AQSync monitors.
These devices can offer communities a useful but limited picture of what's in their air, allowing them to track criteria pollutants and detect pollution flare-ups in areas of concern. However, they struggle to match the sensitivity and precision of the monitors used by regulatory agencies — which cost tens of thousands of dollars to operate and maintain each year on top of their up to $60,000 base price, explained Eben Cross, an atmospheric chemist and co-founder of the air sensor company QuantAQ.
Additionally, even the best commercial sensors can't reliably measure air toxics released by industrial sites.
Given these constraints, commercial air sensors "should not be used in a regulatory context" but can still be "very useful in non-regulatory applications such as providing a better understanding of local air quality, helping in the siting of regulatory monitors, or identifying hot spots," EPA officials wrote in a 2020 memo to regional administrators. Their data could also be used to drive further testing by state regulatory agencies.
Of the 132 air monitoring projects selected for funding under Biden, 18 were located in states bordering the Mississippi River. Grantees, which included state and local governments as well as nonprofits, jointly received over $8 million.
One of these groups, the Ecology Action Center, has used its roughly $440,000 EPA grant to track various criteria pollutants in industrial parts of Central Illinois, making the data available to residents through a website.
"People can get real-time alerts when the air quality index is high," said Michael Brown, the center's executive director, adding that air quality information is processed and updated faster on the group's website than on regulatory platforms.
In neighboring Wisconsin, the City of Madison has used the Biden-era funding to measure particulate matter in each of its census tracts, aiming to identify disparities in air quality between neighborhoods. While the program hasn't uncovered major differences so far, it has produced neighborhood-specific data that could influence city planning and development moving forward, said Gabriel Saiz, Madison's sustainability program coordinator.
In Southwest Louisiana, Robertson's organization has used its commercial air sensors to measure daily levels of particulate matter 2.5 — a mix of airborne particles and droplets that can burrow deep into the lungs when inhaled, causing a range of respiratory illnesses and cardiovascular conditions. The data has shown that for roughly two-thirds of the year, PM2.5 concentrations around Sulphur are higher than the EPA's annual health-based standard.
Despite these elevated readings and appeals to LDEQ, Robertson says she has received no indication that the agency plans to ramp up its own monitoring near Lake Charles or investigate her organization's findings.
LDEQ Surveillance Division Administrator Brian Tusa said that while his team routinely receives pollution complaints from residents, he's not aware of any community groups sharing their air monitoring data with the agency. Data showing recurring pollution spikes could potentially trigger follow-up monitoring from LDEQ, he added, but that would require approval from agency leadership.
"We typically can't use third-party results, because we're not sure of the quality assurance that they're offering or the validity of [the data]," Tusa said.
In May 2024, Louisiana passed the Community Air Monitoring Reliability Act, a law that critics say effectively bars local groups from alleging air quality violations using commercial sensors.
|
