driven by Enbridge Gas’s standard operational maintenance program, it is expected to reduce stationary combustion emissions covered under the OBPS.

• This initiative has already been implemented on two compressor units and Enbridge Gas intends to implement on four additional compressor units by the end of 2021.

• 2. Turbine Air Filter Replacements –

  As part of a program to increase compressor efficiency and reduce maintenance costs, a study was conducted to evaluate current air filtration systems on Enbridge Gas compressors. As a result of this study, Enbridge Gas has developed and is in the process of implementing a program to upgrade turbine air filters and implement a more effective maintenance strategy. This project is anticipated to reduce stationary combustion emissions covered under the OBPS.

• 3. Plant J Twinning –

  An opportunity exists to reduce the overall compressor fleet emissions by installing an electric drive block of compression that could operate parallel to, and in place of, an existing turbine powered compressor. Dawn Plant J is a likely candidate to be displaced during normal operating conditions by an electric drive compressor as it has higher run time hours, is utilized in a consistent manner throughout the year and was constructed with provisions to install a second plant at a future date. This project would reduce stationary combustion emissions covered under the OBPS. However, this project is currently not feasible due to its high cost per tonne compared to the excess emissions charge.

• 4. Re-wheeling Turbines –

  Compressor impellers can be made more efficient by assessing the viability of their design. There may be opportunities to re-manufacture the impellers to be more efficient and thus reduce the amount of combusted emissions. There are currently four units that have not been re-wheeled on the system. This project