CHICAGO (CBS) — As Chicago Fire Department officials faced questions from aldermen about next year’s budget, they were defending overtime spending, and clarifying the department’s response time to emergency calls.

WBBM Newsradio Political Editor Craig Dellimore reports the Fire Department could spend up to $43 million on overtime costs this year, more than double the budgeted $20 million layout.

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The department currently has about 4,700 employees – including uniformed firefighters and civilian workers – short of the estimated 5,100 considered full strength.

Fire Commissioner Jose Santiago said lawsuits over hiring practices have been to blame.

“There was a series of legal issues that the Fire Department had to work through with the Law Department on, that actually effectively stopped us from hiring. The city of Chicago could not hire firefighters. These legal issues stopped that. We have resolved these issues,” he said.

Though he did not provide specifics on the “legal issues,” sources confirmed they were lawsuits tied to department hiring.

Santiago said he was expecting a class of 150 new recruits at the fire academy starting Nov. 18.

Earlier this year, the city paid $2 million to settle a lawsuit filed by female firefighter applicants who failed a physical fitness test, after passing the written test in 2006. Their lawsuit alleged the physical exam was discriminatory, because it focused on brute strength, not the skills required to be a firefighter.

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The city has since scrapped that test, and gave the women who sued a chance to take a new one, which matches federal standards.

Two years ago, a federal judge ordered the city to hire 111 African-American applicants who were passed over for jobs, after passing a 1995 entrance exam. The city also had to pay $30 million in damages to some 6,000 black candidates who took and passed the test, but were not hired.

The judge ruled the 1995 hiring process unfairly eliminated most black candidates. He ruled 111 candidates who passed the test, but were passed over for jobs, must be hired as firefighters.

The city has announced it will hold its first firefighter entrance exam since 2006 next year.

Aldermen also asked about an inspector general’s audit of response times.

Inspector General Joseph Ferguson released an audit earlier this month, determining firefighters arrived on the scene of a fire within 5 minutes and 20 seconds about 82 percent of the time, slightly below the national standard of 90 percent. It also found response time for medical emergencies was well below the national average, with the Fire Department arriving within five minutes only 58 percent of the time.

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Santiago questioned the information, and the math the IG used. He said the average response time is 3 minutes 35 seconds for fires, and 5 minutes and 5 seconds for medical emergencies – meeting state mandates.