Air pollution around St. Paul's Southport Industrial District isn't significantly worse than in other parts of the Twin Cities, but steps still need to be taken to improve air quality, according to a report from the St. Paul Planning Commission.

The 99-acre site, located near the Mississippi River in St. Paul's West Side neighborhood, is home to metals recycling facilities, chemical storage and the city's impound lot. The main air quality problems, according to the study, are "fugitive," or airborne, dust and vehicle emissions — problems that can be mitigated by paving roads and limiting truck idling and diesel emissions.

"A lot of the solutions are relatively straightforward," said Council Member Rebecca Noecker, whose ward includes the West Side. "It takes someone to say, 'Why don't we pave the roads, so that we don't have dust laced with all these chemicals floating around?' "

In 2015, the City Council directed the Planning Commission to conduct a study addressing health and safety issues at Southport, following resident opposition to the planned expansion of a chemical storage facility there. An estimated 474 housing units are within a quarter mile of Southport, according to the study.

The City Council will hear the study results Wednesday.

The 87-page report includes Minnesota Pollution Control Agency air quality monitoring data. In 2014, the MPCA placed a sensor in the parking lot of Our Lady of Guadalupe Church, across the street from Southport. Between April 1, 2014, and June 30, 2014, the sensor detected elevated levels of large dust particles, arsenic and lead, said Kari Palmer, a supervisor in the MPCA's air quality unit.

Those results prompted a full year of monitoring in 2016. The MPCA moved the sensor to the St. Paul Downtown Airport and found lower levels of particulate and both metals, Palmer said.

"We don't think, whatever these metals are, that they're being carried very far," she said. "We suspect a lot of it might just be from the fugitive dust — the fact that there's unpaved roads there, there's material handling."

More MPCA monitoring in the residential area adjacent to Southport is planned for 2018 and 2019, according to the report.

The St. Paul Port Authority owns most of the Southport property, and leases parcels to 11 businesses. Another four businesses operate on private land.

The Port Authority is looking to mitigate dust by paving a private road on the property and encouraging its tenants to do what they can to reduce dust on their own, said Kathryn Sarnecki, vice president of redevelopment and harbor management.

In addition to raising pollution concerns, residents also asked about emergency management. What would happen if there were a chemical spill at Southport, for instance, or a train derailment on the Union Pacific tracks that run through the site? Southport has only one point of access, and it's sometimes blocked by passing trains.

The Port Authority is applying for grants to build a bridge over the railroad tracks, Sarnecki said. The initial estimated project cost is about $9 million, she said.