Construction of Chicago’s first large tent encampment for migrants will not start Monday after all as environmental assessments continue, Mayor Brandon Johnson’s administration said after the site’s alderman over the weekend again objected to the work proceeding.

Following an announcement Saturday from Ald. Julia Ramirez, 12th, that GardaWorld Federal Services — a private security firm the city is contracting to build and run the camps — would begin erecting tents Monday on the lot at 38th Street and California Avenue, mayoral spokesman Ronnie Reese said that was not the case.

“Delivery and staging of equipment has been scheduled for today so construction can begin at a later date,” Reese said in a Monday statement. “There is no construction slated to begin today.”

Reached by phone on Monday, Ramirez maintained she was indeed told by the mayor’s office they had planned for the tent setup to start on Monday.

“I do feel that it is a win that construction is not happening today,” Ramirez said. “It was really important for me to make sure that the administration first convey the finding from the lot, the remediation process and be clear about timeline moving forward.”

Ramirez said she learned the latest update on the construction timeline from news headlines and not the mayor’s office, and “regardless of construction being done today, I think it’s important that the administration be very clear about whether or not they’ve made that decision.”

Asked on Sunday about the timing of construction, Reese had said, “The City is confident that the property will be suited for the purpose for which it will be used,” but did not address Ramirez’s letter to constituents stating tent setup would begin Monday. He also said the weekslong endeavor to assess the site’s viability should conclude later this week.

“The City conducted site visits and investigated preexisting conditions to determine any potential environmental impacts at the site,” Reese said on Sunday. “These common mitigation strategies are ongoing and anticipated for completion by the end of this week, weather permitting.”

Ramirez, the alderman of the Southwest Side ward where the lot is located, has opposed the rollout of Johnson’s plans to turn it into a base camp for incoming migrants as they wait for a bed in the city’s shelter system. She again voiced her frustrations this weekend in announcing the tents were going up despite protests from neighbors.

“The administration’s decision to proceed without addressing our concerns not only undermines transparency and efforts of co-governance,” she wrote, “but also disregards the well-being of everyone in our community, including the asylum-seekers who have come to our great city seeking safety and refuge.”

Ramirez referred to an environmental impact study conducted on the site, the results of which she said have yet to be shared with her or her constituents. She said her office had been informed of the presence of toxic metals in the soil, but even though the pollution had been remediated she still worried about the safety and health of new arrivals.

Local environmental justice activists have raised concerns about what testing, if any, has been carried out at the site. They also say the location proposed to house thousands of the city’s most vulnerable people is in an industrial zone near an interstate and was once home to a zinc smelter that might still render the land toxic.

“It is essential for residents of this community to be fully aware of the environmental impacts and potential risks associated with this project,” Ramirez said. “We have a right to know if the site is safe for both asylum-seekers and community members at large.”

Plans for the first migrant encampment with winterized tents to be set up at Brighton Park were floated around mid-October. The city’s six-month, $548,400 land use contract for the site at 3710 S. California Ave. was approved shortly after, eliciting objections from Ramirez, who said she had not been notified the lease for the site in her ward had been signed.

Growing tensions have spilled out a few times since residents in the Southwest Side neighborhood first got wind of the city’s plans: A crowd swarmed Ramirez at a protest and a few days later a group scuffled with police ahead of a community meeting.

As of Monday, more than 22,600 migrants have arrived in Chicago in the last 15 months, per city data. But as wintry weather continues in the city, the Johnson administration has emptied out eight of the 21 police stations where mini-tent cities had cropped up and families often slept on lobby floors in squalid conditions.

Now 1,200 migrants remain at the Chicago police districts, with another 170 at O’Hare International Airport. That’s down from a peak of about 3,800 migrants across the stations and airports. Another 12,800 of them were at the city-run shelters.

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