Of the more than 700 companies to express interest in working on the proposed border wall between the United States and Mexico, at least 15 have Chicago-area connections, federal government records show.

Two of those 15 have also gotten contracts to do work for the city of Chicago, a Chicago Sun-Times analysis found.

Records show Scale Construction, based in Pilsen, was awarded a $3.68 million contract with the city in 2010 to modernize bathrooms at O’Hare Airport.

Glen Ellyn-based Northwest General Contractors has been awarded two contracts with the city. One came in 2010 for $681,505 to expand the Midway Airport employee parking lot. The other, for $4,550, came in February 2011 to help with emergency snow removal.

It isn’t known what type of wall-building contracts Scale and Northwest General might be interested in. Federal records don’t say, and neither company responded to requests for comment.

Customs and Border Protection, the Homeland Security agency that will eventually patrol and maintain any new fencing or walls, has asked contractors to submit proposals for a 30-foot-high wall that is difficult to climb or cut through. Bids were originally due to the government by March 29, but the deadline was extended to April 4 amid questions from possible bidders.

In a pair of contract notices made public two weeks ago, the government said proposals could lay out plans for a solid concrete wall or a structure that can be seen through by border agents.

Earlier this month, two San Francisco city supervisors submitted legislation that would bar their city from doing business with any contractor who worked on the border wall, according to the San Francisco Chronicle.

It’s unclear, though, if potential work on the wall would affect companies’ ability to procure contracts from Chicago’s City Hall. Mayor Rahm Emanuel’s administration didn’t respond to requests for comment.

Of the other 13 Chicago-area companies that have expressed an interest in helping build the wall — including private security firms, pipe suppliers and several construction companies — only two responded to Sun-Times inquiries. Both said they have no intention of actually bidding on border-wall work.

Arthur Handelman, of Pyrophase, an energy company with offices in Chicago and Spokane, Wash., said the company listed itself as an interested vendor “just out of curiosity.”

“Nothing has been submitted and we’re not pursuing anything,” Handelman said.

Peter Lind, of Lind Associates, an architecture firm in north suburban Winnetka, said in an email Wednesday: “While interested in the process, my firm did not submit a proposal. Further, I have, or prefer to say little more.”

The construction of the border wall was a centerpiece of President Donald Trump’s campaign.

An internal report prepared for Homeland Security Secretary John Kelly estimated that a wall along the entire border would cost about $21 billion. Congressional Republicans have estimated a more moderate price tag of $12 billion to $15 billion.

Customs and Border Protection said in a statement that cost estimates are “premature as there are many variables that are currently unknown.” The agency said it could not provide a detailed estimate for the project.

In recent months, Trump’s administration has considered a 20 percent import tax to cover construction costs.

The border is already dotted with underground sensors and camera towers, along with about 700 miles of fencing in Texas, New Mexico, Arizona and California. It’s unclear how much new fencing the Trump administration is proposing.

According to new budget details sent to Congress, the administration wants immediate funding to complete an existing barrier in the Rio Grande Valley, $500 million to complete 28 miles of a border levee wall near McAllen, Texas, and $350 million for construction along two segments near San Diego.

Senate Democrats have threatened to filibuster any provision providing money for the wall. Many Republicans aren’t very enthusiastic about the plan and say the White House has given them few specifics.

Republican Sen. Roy Blunt of Missouri, a key budget negotiator, said the Senate is unlikely to include money for a border wall in a broader spending package to avert a partial government shutdown next month.

Contributing: Associated Press, Lynn Sweet