PONTIAC (AP) — A group of Illinois lawmakers have gotten a look at how the Pontiac Correctional Center is preparing for an overhaul to treat mentally ill prisoners.

The Springfield bureau of Lee Enterprises newspapers reports lawmakers toured the maximum-security facility in Pontiac on Monday. Renovations are expected to begin in December and warden Randy Pfister says they could finish in 18 months.

The changes are part of an ongoing federal lawsuit seeking better care for Illinois’ mentally ill inmates. A proposed settlement also includes renovations at Dixon and Logan correctional centers and the conversion of a former Joliet youth prison.

The state said in February that it could take five years to fully institute changes. The upgrades are estimated to cost $29 million, with $62 million needed to pay additional workers.