The Wisconsin Department of Natural Resources is taking comment until Oct. 12 on a draft approval of an air permit revision that covers a plan by Wisconsin Electric Power d/b/a We Energies to shut the coal-fired boilers at the Milwaukee County cogeneration plant.
The company is requesting a significant revision to an operation permit to incorporate the approved extension of the compliance date forthe National Emission Standards for Hazardous Air Pollutants (NESHAP) for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters (ICI Boiler MACT). On July 24, 20015, We Energies was issued an ICI Boiler MACT compliance date extension for boilers B21, B22, and B23 by the department. Incorporated into this operating permit revision are the extended compliance date and the department’s conditions for approving the compliance date extension.
Under the ICI Boiler MACT, the facility’s three existing coal boilers (Boilers B21, B22, and B23) have a compliance date of Jan. 31, 2016. To comply with the ICI Boiler MACT, the company is electing to permanently shut down the three coal boilers. Before these boilers can be shut, their steam generating capabilities need to be replaced. As part of a proposed sale of the facility, the steam generating capabilities for the three coal boilers will be provided by replacement boilers operated by Milwaukee Regional Medical Center Thermal Services (MRMCT).
A transitional plan calls for MRMCT to install and operate four temporary natural gas boilers. Once the gas boilers are installed and fully operationally, the three existing coal boilers (Boilers B21, B22, and B23) will be permanently shut down. The approval letter issued to the permittee extends the compliance date, and the dates associated with demonstrating initial compliance, under the ICI Boiler MACT for boilers B21, B22, and B23 to June 1, 2016, so the replacement boilers can be installed and tested and the three coal boilers can be shut down.
An approval letter allows the department to extend the compliance date for unforeseen delays and good cause, not to exceed Jan. 31, 2017. The permit allows a further extension of the compliance date, beyond Jan. 31, 2017, if the U.S. EPA approves the extension.
Milwaukee County Power Plant (MCPP) supplies steam heat, process steam, and chilled water to the Milwaukee Regional Medical Center, member institutions, and other county-owned facilities. MCPP also cogenerates electricity. While the facility may send electricity to the grid, the facility does not meet the air program definition of an electric utility and the boilers are not classified as electric generating units.
The facility operates three coal-fired boilers, one oil/gas-fired boiler, one gas-fired boiler, an ash transfer system for the coal-fired boilers and four cooling towers with thirteen separate cells. The facility may be sold to Milwaukee Regional Medical Center Thermal Services.
As part of the transition to gas boilers, MRMCT will install four temporary natural gas-fired boilers (with distillate backup), a 1-MW emergency generator, and a 20,000-gal distillate oil storage tank.
A construction permit issued on May 27, 2015, authorizes MRMCT to construct and initially operate the transitional gas boilers that temporarily replace the existing coal boilers operated by We Energies. The boilers will be located on the existing site. Eventually the temporary boilers will be replaced with permanent boilers. MRMCT will be the operator of the temporary and replacement boilers, and eventually, after the sale of the site, the facility itself.