CHICAGO (CBS) — Mayor Rahm Emanuel is defending what the city’s Inspector General has suggested is stonewalling of his office’s efforts to audit Chicago’s new grid-based trash collection system.

WBBM Newsradio Political Editor Craig Dellimore reports Inspector General Joe Ferguson said Streets and Sanitation Commissioner Charles Williams walked out of a meeting at which Ferguson was demanding figures to verify the Emanuel administration’s claim of $18 million in annual savings by collecting trash on a grid map, rather than ward-by-ward.

The mayor said the issue isn’t about transparency, but timing.

“Today, there’s about 312 trucks out. If we didn’t do grid garbage, there’d be 360 trucks out. And as I said – and I told Charlie to tell him – once it’s fully implemented, come in, audit it, so we can see and realize the $18 million in savings,” he said.

The mayor’s just not ready to provide those numbers yet.

However, even the $18 million in savings estimated by the mayor’s office would be much lower than the $60 million in savings Emanuel promised when he ran for mayor in 2011.

Emanuel also defended his decision to make Ferguson – who has questioned city programs before – reapply for his job, saying it was the recommendation of a blue ribbon panel.

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