Document MMJ9LgdbrvbyKeR9jVLjjDwgx

Further, Minnkota has no information or data supporting the conclusion that Unit 1 or Unit 2 can achieve the New Mercury Limitation on a 30-day rolling basis while operating at full load. The short-term testing data suggest that even a longer-term averaging period would not result in compliance. The technology that EPA used to set the limitations of the revised MATS RTR cannot feasibly control emissions on Unit 1 and Unit 2 to meet the reduced limit, because the Young Station does not have the technology available for compliance with the revised MATS RTR limitations. Minnkota further tested Unit 1 by adding more PAC than the Unit's system is capable of injecting by renting portable equipment. However, the results show that even injecting more PAC will not achieve the new mercury limit. The plotted curve shown in the figure shows a leveling off such that increasing the amount of sorbent results in diminishing improvement in Hg control. The projected curve based on the test campaign results shows this leveling off taking place somewhere less than 80% capture." The plotted trend line, based on the test values, is far below EPA's conclusion that injection of brominated PAC at the rate of 3.0 lb/MMacf will result in a 90% removal rate and in line with the ACI Fuel 2010 Article. Consequently, increasing the amount of brominated PAC is not an adequate control strategy to achieve the New Mercury Limitation. The scatterplot from Minnkota's Study is presented below. 1000 so 0 80 o a s .; 70 o -- 1,0 0 50 0 40 0 000 0S0 00 ISO 2 0D 2 50 300 3 SO Btommated PAC Injection Rate, IbilillMad Compliance with MATS RTR places Minnkota in an urgent and untenable position, given the impending compliance date. Noncompliance with the Clean Air Act is not an option. Therefore, prior to making a shutdown decision regarding critical assets, Minnkota must undertake more study and testing to determine what mercury emission rate the Young Station units can achieve with the technology available. That would require significant additional investment in testing along with installation of new equipment. We estimate this amount will exceed approximately $600,000.00. Minnkota must also spend money on design and installation An Equai Opportunity and Affirmative Action Frnpinyer. Sierra Club FOIA 2025-EPA-04883 ED_018388_00000327-00008 SC_EVERSPLIT0006317