Ill. Admin. Code tit. 74 § 730.170
Prior to the hearing, an unopposed motion to voluntarily dismiss or withdraw a Petition for Hearing/Notice of Hearing shall be granted, and the Hearing Officer shall issue an order dismissing the Petition for Hearing/Notice of Hearing and its underlying cause with prejudice. However, the Hearing Officer, within his or her discretion, may hear and decide a motion that has been filed prior to a motion to voluntarily dismiss or withdraw when that prior filed motion could result in a final disposition of the cause. After a hearing begins or when a motion to voluntarily dismiss or withdraw is challenged, the Hearing Officer shall exercise discretion in allowing the motion when the voluntary dismissal or withdrawal would serve the interests of justice.
Ill. Admin. Code tit. 74, § 730.170