McLean County, IL Data Centers & Crypto Mining: Data Center Noise Limits (2026)

McLean County did not write its own decibel table for data centers. Instead, § 350-43FFF(8) incorporates state law wholesale, requiring the data center to comply with noise limits established by the Illinois Pollution Control Board. The IPCB sets numeric sound limits, and a McLean County data center operator has to meet those state limits as a condition of its zoning approval, in addition to the county's own general performance standard at § 350-53A, which separately bars any use from creating noise in violation of the applicable standards and regulations governing noise levels specified by the Illinois Environmental Protection Agency.

Reading the two together, a data center's noise is checked against the state IPCB and IEPA framework rather than a locally set decibel cap, and either the Director of Building and Zoning or a complaining neighbor can raise a noise problem as a zoning violation. This dual reference, one naming the IPCB in the use-specific standard and one naming the IEPA in the general performance standard, reflects how Illinois splits noise rulemaking from enforcement at the state level; McLean County simply cross-references both bodies rather than adopting independent local limits.