17.8.771    MERCURY EMISSION STANDARDS FOR MERCURY-EMITTING GENERATING UNITS

(1) Except as provided in (3) , the owner or operator of a mercury-emitting generating unit shall:

(a) if obtaining a Montana air quality permit pursuant to ARM 17.8.743, install best available control technology for control of mercury emissions as required by ARM 17.8.752;

(b) except for any period for which another mercury emissions limit has been established pursuant to this rule, beginning January 1, 2010, or at commencement of commercial operation, whichever is later, limit mercury emissions from the mercury-emitting generating unit to an emission rate equal to or less than:

(i) 1.5 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for mercury-emitting generating units that combust lignite; or

(ii) 0.9 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for all other mercury-emitting generating units;

(c) by January 1, 2009, or 12 months prior to commencement of commercial operation, whichever is later, submit an application to the department for a Montana air quality permit or modification of an existing Montana air quality permit for the mercury-emitting generating unit solely to establish the mercury emission limit from (1) (b) and any necessary operational requirements as a condition of the permit. The owner or operator shall include in the application an analysis of potential mercury control options including, but not limited to, boiler technology, mercury emission control technology, and any other mercury control practices. The owner or operator shall also include in the application a proposed mercury emission control strategy projected to achieve compliance with the emission limit in (1) (b) and that must include boiler technology, mercury emission control technology, or any other mercury control practices used or anticipated to be used by the owner or operator to achieve compliance with (1) (b) . If the department determines that the mercury emission control strategy is projected to achieve compliance with the emission limit in (1) (b) , the department shall include the provisions of the mercury control strategy as conditions of the Montana air quality permit; and

(d) by January 1, 2010, or at commencement of commercial operation, whichever is later, implement the mercury emission control strategy approved pursuant to (1) (c) .

(2) If more than one mercury-emitting generating unit is located at a facility, the owner or operator may demonstrate compliance with the requirements of (1) (b) , an alternative emission limit, or a revised alternative emission limit on a facility-wide basis. An owner or operator choosing to demonstrate compliance with this rule on a facility-wide basis shall report the information required in (11) on a facility-wide basis.

(3) If the owner or operator of a mercury-emitting generating unit properly implements the mercury control strategy approved pursuant to (1) (c) , and the mercury control strategy fails under normal operation to meet the emission rate required in (1) (b) , the owner or operator:

(a) shall notify the department of the failure to meet the emission rate required in (1) (b) by March 1, 2011, or within two months of such failure, whichever is later; and

(b) may submit an application to the department for a Montana air quality permit or a modification of a Montana air quality permit solely to establish an alternative mercury emission limit. The owner or operator shall file any application for an alternative emission limit by July 1, 2011, or within six months of the failure to meet the emission rate required in (1) (b) , whichever is later, and shall include as part of the application:

(i) all mercury emission monitoring data, obtained pursuant to (11) , for the mercury-emitting generating unit;

(ii) a description of the reason(s) for the failure and any corrective action that may be appropriate;

(iii) a certification that the failure occurred during normal operation of the facility and was not caused entirely or in part by start-up, shakedown, or improper implementation of the mercury control strategy approved pursuant to (1) (c) ; and

(iv) a revised mercury control strategy demonstrating how compliance with (1) (b) is projected to be achieved as soon as reasonably practicable but no later than 2018. The revised mercury control strategy may include, but is not limited to, boiler technology, mercury emission control technology, and any other mercury control practices used or anticipated to be used by the owner or operator to achieve compliance with (1) (b) . The revised mercury control strategy must include measurable indicators of progress toward compliance with the emission limit in (1) (b) , which may include a plan of increasing levels of mercury control progressing to compliance with (1) (b) .

(4) If an application is submitted in accordance with (3) (b) , the failure of the owner or operator of the mercury-emitting generating unit to comply with the mercury emission limit in (1) (b) is not a violation of this rule or the permit until the department has issued its final decision on the application.

(5) If the information submitted pursuant to (3) (b) demonstrates that the owner or operator of the mercury-emitting unit cannot reasonably comply with the mercury emission limit in (1) (b) , the department may establish an alternative mercury emission limit, except that the department may not require the owner or operator to install a different boiler technology than is in use or contained in a final air quality permit. The department may establish an alternative mercury emission limit only if the owner or operator of the mercury-emitting unit demonstrates that the revised mercury control strategy constitutes a continual program of mercury control progression able to achieve the mercury emission rate requirement of (1) (b) . If the department establishes an alternative mercury emission limit, the department must include as a condition of the permit a requirement that the owner or operator of the mercury-emitting generating unit make reasonable efforts toward achieving the measurable indicators of progress contained in the revised mercury control strategy. Failure to make reasonable efforts toward achieving the measurable indicators of progress contained in the revised mercury control strategy is a violation of the permit. The department shall base any alternative mercury emission limit on the best level of emission control achieved or achievable by the revised mercury control strategy and shall consider the information submitted pursuant to (3) when establishing the alternative mercury emission limit.

(6) An alternative mercury emission limit established in a Montana air quality permit expires January 1, 2018, and must not exceed:

(a) 4.8 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for a mercury-emitting generating unit that combusts lignite and commenced commercial operation prior to October 1, 2006;

(b) 3.6 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for a mercury-emitting generating unit that combusts lignite and commenced commercial operation on or after October 1, 2006;

(c) 2.4 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for a mercury-emitting generating unit that does not combust lignite and commenced commercial operation prior to October 1, 2006; or

(d) 1.5 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for all other mercury-emitting generating units that do not combust lignite.

(7) The owner or operator of a mercury-emitting generating unit, for which the department has established an alternative mercury emission limit, shall, by January 1, 2014, submit an application to the department for a Montana air quality permit or a modification of a Montana air quality permit for the mercury-emitting generating unit to establish a revised alternative mercury emission limit. The owner or operator shall submit, as part of any application, the information required in (3) (b) (i) through (iv) , a best available control technology analysis for the control of mercury emissions, a review of the mercury-emitting generating unit's existing alternative mercury emission limit, including associated mercury emission monitoring and operational data, and a revised mercury control strategy.

(8) In reviewing an application submitted pursuant to (7) , the department shall establish a revised alternative mercury emission limit in a Montana air quality permit that will become effective beginning January 1, 2018. A revised alternative mercury emission limit must meet the requirements of (5) , except that the department may not require the owner or operator to install a different boiler technology than is in use or contained in a final air quality permit, or constitute best available control technology, whichever is more stringent, but must not exceed:

(a) 2.8 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for a mercury-emitting generating unit that combusts lignite; or

(b) 1.2 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for all other mercury-emitting generating units.

(9) No later than ten years after issuance of the permit containing the mercury emission limit, and every ten years thereafter, the owner or operator of a mercury-emitting generating unit, for which the department has established a mercury emission limit under (1) (b) or (8) , shall file an application with the department for a Montana air quality permit or a modification of a Montana air quality permit for the mercury-emitting generating unit to establish a revised mercury emission limit. The owner or operator shall submit, as part of the application, the information required in (3) (b) (i) through (iv) , a best available control technology analysis for the control of mercury emissions, and a review of the mercury-emitting generating unit's existing alternative mercury emission limit and the mercury control strategy, including associated mercury emission monitoring and operational data. The department shall establish a revised mercury emission limit in a Montana air quality permit that meets the requirements of (5) , except that the department may not require the owner or operator to install a different boiler technology than is in use or contained in a final air quality permit, or constitutes best available control technology whichever is more stringent, but that must not exceed:

(a) 2.8 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for a mercury-emitting generating unit that combusts lignite; or

(b) 1.2 pounds of mercury per trillion Btu, calculated as a rolling 12-month average, for all other mercury-emitting generating units.

(10) The owner or operator of a mercury-emitting generating unit shall comply with the monitoring, recordkeeping, and reporting provisions of 40 CFR Part 75. Any continuous emissions monitors used must be operated in compliance with 40 CFR Part 60, Appendix B.

(11) The owner or operator of any mercury-emitting generating unit shall report to the department within 60 days after the end of each calendar quarter, on forms as may be prescribed by the department:

(a) the monthly average mercury emission rate, for each month of the quarter; and

(b) the percentage of time the mercury emission monitoring method was operating during the quarter.

(12) If the federal Clean Air Mercury Rule (CAMR) , adopted in 70 Fed. Reg. 28606 (May 18, 2005) , is declared invalid by a court of competent jurisdiction, the provisions of 40 CFR Part 75 and Part 60, Appendix B, amended by CAMR, as they pertain to monitoring, recordkeeping, and reporting of mercury emissions, remain in effect as incorporated by reference in ARM 17.8.767(1) .

History: 75-2-203, 75-2-204, 75-2-211, MCA; IMP, 75-2-211, MCA; NEW, 2006 MAR p. 2575, Eff. 10/27/06.