A long-running project to widen the 710 Freeway hit a new hurdle after the EPA has required planners to conduct a detailed pollution study that is likely to show added truck traffic will increase pollution in an area already burdened by bad air.

The Environmental Protection Agency issued a letter in March requiring that officials behind the 710 Freeway widening project—which would add two lanes of truck traffic on either side of the freeway—perform a particulate matter “hot-spot” analysis. Not completing the analysis would put the project in non-compliance with the Clean Air Act, federal officials said.

The project area spans from Long Beach to East Los Angeles near the 60 Freeway. The existence of the EPA letter was first reported May 4 by StreetsBlogLA.

The project could increase truck-traffic by 6,900 trips per day in addition to the 50,000 trucks and 165,000 commuter vehicles that use the freeway daily already, according to a technical analysis from the EPA.

The EPA’s letter said a plan to require and help pay for cleaner-burning trucks as part of the project wouldn’t do much to improve existing pollution issues.

“In fact, we expect increases in the severity of existing violations even if the proposed I-710 Clean Truck Program were to be fully implemented given dust, tire wear and brake wear,” Elizabeth Adams, the EPA’s director of Air & Radiation Division, wrote in the letter.

Metro’s Board of Directors unanimously approved a $6 billion version of the widening project in March 2018. However, a lack of funding and the finalization of environmental documents have put much of the project on hold.

The March 25 letter sent to LA County Metro CEO Philip Washington and Tony Tavares, CalTrans’ director of the district that includes Los Angeles, said that the program’s proposed $200 million clean-trucks program is a mitigating factor, but does not excuse officials from having to conduct the hot-spot analysis.

The hot-spot analysis would estimate the future pollutant concentrations and the air quality impacts of the project. Long Beach and other cities along the 710 Freeway have some of the worst air quality in the United States and larger percentages of respiratory disease than other parts of the country.

“LA Metro is in the process of evaluating the I-710 Corridor Project and the timeline based on the EPA letter, in consultation with Caltrans,” a spokesperson for Metro said in an email Friday.

A spokesperson from CalTrans said that Metro is the lead agency on the project and CalTrans could not comment on any impacts to the schedule.

There is a chance the project could move forward without completing the analysis, but it would open it up to legal challenges.

Adrian Martinez, an LA-based attorney who has been representing community groups opposed to the current project, said the project in its current form is a “1950s solution to a modern problem” that would just make the public health situation worse.

Martinez explained that unlike the state’s air quality laws, which allow projects to move forward even if studies show that they could make pollution worse, the federal Clean Air Act does not.

“I do think the days of this project are numbered,” Martinez said. “And this effort shows an incredible story of perseverance, organizing and community empowerment.”

Community groups have fought the expansion of the freeway for years and demanded that any project benefit the communities surrounding the 710 and the ports of Los Angeles and Long Beach that are already burdened with pollution.

Organizers view the EPA’s letter as an encouraging sign that the project could be brought back to the table for public discussion, if not outright blocked by the federal government.

“EPA articulated and came to the conclusions the community had known all along that a project adding diesel truck lanes would be bad for air quality,” a statement from the Coalition for Environmental Health and Justice said, which includes groups represented by Martinez.

“As a result, this EPA letter provides the perfect opportunity to stop this harmful project proposal, which is pushing forward decades old thinking of how to solve our transportation and air quality problems.”

The coalition includes community groups in Long Beach and other cities that sit on either side of the 710 corridor.

Laura Cortez, an organizer for East Yards Communities for Environmental Justice, an advocacy group representing cities in Southeast Los Angeles that is part of the coalition, said she’s hopeful that Metro and CalTrans will reopen discussions for the project.

“This specific process wouldn’t have taken 20 years if they got it right and listened to the community,” Cortez said.

The coalition of nine community groups is calling for the project to be renegotiated with benefits like better public transit options along the 710 corridor.

Opponents are also calling for the project to eliminate any displacement that might result from construction. Over 100 residential and commercial properties were at risk of displacement due to the project adopted in 2018.

Among the things the coalition called for in a statement issued this week, Cortez said she’s hopeful that any project uses the same footprint of the existing 710, and that could include adding elevated truck-only lanes, but making the 710 corridor less polluted is the highest priority.

“However you move [cargo], it needs to be zero emission,” Cortez said.

Editors note: The story has been updated to include a comment from a spokesperson from CalTrans.