MI HB4778

Requires oil and gas well operators to install methane control or capture systems capable of reducing fugitive methane emissions by 99%, effective for permits issued after the bill's enactment date.

Prohibits use of flaring as a methane control method and exempts wells consisting only of a wellhead from the requirement.

Provides a 180-day grace period for wells permitted before the bill's effective date to comply with the new requirements, unless an earlier date is specified by the supervisor's rules.

Imposes a $100,000 civil fine for violations, unless the methane system malfunctions and the operator promptly repairs it.

Authorizes the supervisor to revoke a well operator's permit if the methane control system is not installed within 3 months (or 1 month for wells emitting more than 1 gram of methane per second) after the required date.