55 ILCS 5/5-25006
When the proposition is submitted to the voters of two or more adjacent counties, the ballots shall be counted and the returns made to the county clerk of each county, respectively, in the same manner as in the case of returns to the county clerk in a general election. The returns shall be opened and canvassed by a committee made up of the county clerk of each county in which the vote on the proposition was cast, and the chairman of the county board of each county. The committee will convene at the request of the chairman of the county board of any one of the counties in which the vote on the proposition was cast. The committee shall elect a chairman whose duty it will be to see that the returns are opened and canvassed by the committee and that the result is declared.
55 ILCS 5/5-25006