Seminole Electric Cooperative in a Dec. 17 letter asked the Florida Department of Environmental Protection for a one-year extension of the federal Mercury and Air Toxics Standards (MATS) compliance deadline of April 2015 for its coal-fired Seminole Generating Station (SGS), with DEP records showing no decision by the agency as of Jan. 13.
“Seminole is currently evaluating its emission levels, operational requirements, and what actions it must take at SGS to comply with these revisions,” said the letter. “For example, the requirement to operate PM controls within one hour of firing coal cannot be safely met at SGS. These units utilize electrostatic precipitators (ESPs) whose inherent electric fields provide an ignition source for any explosive mixtures that may be in their presence. Such mixtures may exist in the ESP until adequate temperatures and conditions are established and maintained in this PM control equipment in accordance with OEM design requirements. As such, Seminole requests relief from this provision in 40 CFR 63 .10011(g)(4 ).
“Additional evaluation is ongoing at Seminole to prepare for compliance with the remaining provisions of the MATS rule, including the recent revisions related to startup and shutdown. This evaluation will take time to complete, and any actions that Seminole must take, such as installing additional controls or monitoring devices, will require additional time.
“The MATS rule requires existing units to comply with these standards by April 16, 2015, and also authorizes the Florida Department of Environmental Protection (FDEP) to grant an extension of the compliance deadline for up to 12 months, or until April 16, 2016, if such additional time is necessary for the installation of controls.
“In order to comply with the MATS requirements, and particularly the November 19, 2014 revisions related to startup and shutdown, Seminole is evaluating its emission levels and operational requirements during all operational scenarios, and may need to install additional controls or monitors at SGS. For example, Seminole requires additional time to study the feasibility of reaching the appropriate operating conditions using clean fuels as required in the latest MATS revision. If additional controls and monitors are needed, Seminole will need time to engineer, procure, install, and verify them in order to fully comply with the MATS requirements while reasonably assuring the continued reliability of Seminole’s electric service to its member cooperatives. The evaluation, and installation of these additional controls and monitors cannot be completed and verified prior to April 16, 2015.
“Seminole has recently completed a study to determine if it is possible to retrofit Units 1 and 2 with dual clean fuel igniters to lower carbon dioxide emissions. The estimated cost of such a project would be over $15 million. If undertaken, this project could not begin until the fall outage of 2015, and would need additional time to address all the safety and operations concerns associated with burning dual fuels. Accordingly, Seminole is requesting a 12-month extension of the MATS compliance deadline for SGS Units 1 and 2 to (1) evaluate compliance obligations related to EPA’s November 19, 2014 revisions, including the possible need for additional controls and monitors, (2) install additional controls and monitors as needed, and (3) have a period of operational monitoring, verification, and experience with the additional controls under a wide range of actual operating conditions. If Seminole can accomplish these actions prior to April 16, 2016, it will make a good faith effort to do so.”
SGS consists of two 650-MW coal-fired generating units and began commercial operation in 1984.To supply the coal needed to operate the station, an average of 9,300 tons of coal arrives daily, traveling more than 800 miles on unit trains via CSX Transportation. “Seminole has more than $530 million invested in state-of-the-art environmental control technology at SGS – making it one of the cleanest coal plants in the United States,” said the Seminole website. “But just as important, it is also one of the most reliable plants in the country.”