Ariz. Admin. Code § R18-2-734 - Standards of Performance for Mercury Emissions from Electric Generating Units

A. Applicability and Purpose. The requirements of this Section apply to owners and operators of electric generating units. The purpose of this Section is to establish:

1. Interim standards for mercury emissions from electric generating units that shall apply until compliance with the emissions limits in the federal mercury standards is required.

2. State standards for mercury emissions from electric generating units that shall apply if the federal mercury standards are vacated by a federal court or repealed by the administrator.

B. Interim Standards. The following requirements shall apply until the date that compliance with the federal mercury standards or subsection (G) is required:

1. The owners and operators shall comply with the mercury control strategy operations and maintenance plan approved as part of the permit for the electric generating plant.

2. The owners and operators shall operate and maintain the electric generating plant, including any associated air pollution control equipment, in a manner consistent with good air pollution control practices for minimizing mercury emissions. This requirement shall apply to any air pollution control equipment installed pursuant to paragraph (B)(1) or to any new air pollution control equipment installed to comply with the federal mercury standards if such equipment replaces equipment installed pursuant to paragraph (B)(1).

C. Incorporation of Federal Mercury Standards. The federal mercury standards in 40 CFR Part 63, Subpart UUUUU, as of July 1, 2013 (and no future amendments or editions) are incorporated by reference and shall remain effective to the extent specified in this Section regardless of whether they are vacated by a federal court or repealed by the administrator. Subpart UUUU of 40 C.F.R. Part 63 is published by the United States Government Printing Office, 732 North Capital Street, NW, Washington, DC 20401-0001, is on file with the Department of Environmental Quality, 1110 West Washington Street, Phoenix, Arizona 85007, and is available at the Arizona State Library, Archives & Public Records, 1700 West Washington Street, Phoenix, Arizona 85007 and at other Federal depositary libraries in the state (see http://catalog.gpo.gov/fdlpdir/FDLPdir.jspst_12=AZ&flag=searchp). It is also available online at http://www.gpo.gov/fdsys/ browse/collectionCfr.actioncollectionCode=CFR. The owners and operators shall provide to the director a copy of all notices and reports submitted to the Administrator under the federal mercury standards, except for any reports or data submitted to the Administrator through electronic systems (for example, Compliance and Emissions Data Reporting Interface (CEDRI), Emission Collection Monitoring Plan System Client Tool (ECMPS) or the Emissions Reporting Tool (ERT)).

D. Notice of State Standard Applicability. The director shall provide notice to the responsible official for each electric generating plant of any repeal or federal court vacatur of the federal mercury standards. If the repeal or vacatur occurred after the date the electric generating plant was required to comply with the emission limits in the federal mercury standards, the plant shall continue to comply with the federal mercury standards until the date that compliance with subsection (G) is required.

E. Application for Permit Revision. Within 120 days of receipt of written notice from the director under subsection (D), the owners and operators shall submit an application for a permit revision that proposes:

1. The mercury emission limit or limits in subsection (G) that shall apply to the electric generating plant.

2. A date for demonstrating compliance with the mercury emission limit consistent with subsection (F)(2).

3. A mercury monitoring plan consistent with subsection (H)(2).

F. Permit Revision Setting State Standard. A permit revision granted in response to the application submitted under subsection (E) shall contain the following conditions:

1. The mercury emission limit or limits in subsection (G) that shall apply to the electric generating plant.

2. The date compliance with the emission limit or limits shall be required. Unless the application requests an earlier date, the compliance date shall be the later of December 31, 2016 or the end of the first averaging period commencing no later than 180 days after permit issuance.

3. The date for demonstrating initial compliance with the emission limit or limits, which shall be 45 days after completion of the first full averaging period after the compliance date established under subsection (F)(2).

4. The date on which compliance with subsection (B), or the obligation to comply with the federal mercury standards in subsection (D), as applicable, shall no longer be required.

5. A mercury monitoring plan consistent with subsection (H).

6. Compliance reporting requirements consistent with subsection (I).

G. State Mercury Emission Limits. Emissions from an electric generating unit shall comply with one or more of the emission limits specified in the following table, as selected by the owners and operators under subsection (F).

No.	Limit	Averaging Period	Applicable To
1.	10 percent of inlet mercury	Rolling 12-month	Electric generating plant
2.	0.0087 pounds per gigawatt-hour	Rolling 12-month	Electric generating plant
3.	0.011 pounds per gigawatt-hour	Rolling 90-boiler operating days	EGUs identified in averaging group
4.	1.0 pounds per Trillion Btu	Rolling 90-boiler operating days	EGUs identified in averaging group
5.	0.013 pounds per gigawatt-hour	Rolling 30-boiler operating days	Individual electric generating unit
6.	1.2 pounds per Trillion Btu	Rolling 30-boiler operating days	Individual electric generating unit

H. Compliance Monitoring and Recordkeeping.

1. Compliance with subsection (G) shall be determined using a mercury CEMS or sorbent trap monitoring system pursuant to Appendix A of the federal mercury standards and in accordance with an approved mercury monitoring plan.

2. The mercury monitoring plan shall include the following elements:

a. Identification of the emission limit or limits in subsection (G) for which compliance will be demonstrated.

b. Identification of whether a mercury CEMS or sorbent trap monitoring system will be used as the primary compliance method. Backup methods may be identified and approved in the plan.

c. Description of the parameters that will be monitored, including mercury concentration, stack flow, fuel mercury content, fuel rate, electricity generation rate, moisture percent, and any diluent or other gas or process parameters necessary to calculate compliance in terms of the applicable emission limit.

d. Description and example of the calculations required to convert monitored parameters to mercury emissions in terms of the emission limit.

e. Establishment of CEMS analyzer data availability, and QA/QC requirements.

f. Procedures for completing an initial demonstration of compliance, except as otherwise provided in subsection (I)(1).

2. At least once per month, the mercury emissions data shall be compiled into a record demonstrating compliance with the emission limit or limits established in the permit revision issued under subsection (F). This record shall be completed no later than the 15th day of the following month.

3. Records shall be maintained as follows:

a. Records demonstrating compliance with the emissions limits shall be maintained for five years.

b. If a mercury CEMS is used, daily CEMS data, QA/QC data identified in the mercury monitoring plan, any maintenance work conducted on the CEMS or data logging system, and a calculation of all mercury CEMS downtime shall be maintained for five years.

c. If a sorbent trap monitoring system is used, all sorbent monitoring data and any maintenance work conducted on the system shall be maintained for five years.

I. Reporting. The owners and operators shall submit to the director the following reports:

1. An initial demonstration of compliance, which must be submitted to the director within 180 days after completion of the first full averaging period. This requirement shall not apply to an electric generating unit if an initial demonstration of compliance has been completed for that unit under 40 C.F.R. 63.10005(d)(3) and the demonstration shows compliance with subsection (G) for that unit. The report shall include:

a. The name of the electric generating plant and electric generating units.

b. The applicable emission limit or limits for the plant or the electric generating units.

c. The mercury emissions for the plant, group of averaged units, or each unit, as applicable, during the initial compliance demonstration in terms of the applicable standard.

d. A certification by a responsible official.

2. Semiannual compliance reports, which must be submitted to the director on the dates established in the electric generating plant's air quality permit. The report shall include:

a. The name of the electric generating plant and electric generating units;

b. The applicable emission limit or limits for the plant or the electric generating units.

c. The mercury emissions for the plant, or each unit, as applicable, for each month during the six month period ending the month prior to the semiannual report in terms of the applicable standard.

d. An explanation of any excess emissions, the duration of the excess emissions, and corrective actions taken, if any, to resolve those excess emissions.

e. A certification by a responsible official.

J. Exemption. After receipt of notice under subsection (D), in lieu of submitting the permit revision application required by subsection (E), the owners and operators may notify the director in writing that they elect to comply with the vacated or repealed federal mercury standards at an electric generating plant. If the owners and operators for an electric generating plant make this election, the plant shall be exempt from subsections (E) through (I). If the owners and operators of an electric plant elect this option:

1. "Administrator" shall mean "Director" whenever it appears in the federal mercury standards or regulations referenced therein.

2. "EPA" shall mean "ADEQ, Air Quality Division" whenever it appears in the federal mercury standards or regulations referenced therein.

3. In lieu of reports submitted to the Administrator through electronic systems (for example, Compliance and Emissions Data Reporting Interface (CEDRI), Emission Collection Monitoring Plan System Client Tool (ECMPS) or Emissions Reporting Tool (ERT)) pursuant to the federal mercury standards, the owners or operators shall submit to the Director, semiannually at the time required by permit, the RATA or the rolling 30-day or rolling 90-day average mercury value for each EGU or the plant, as applicable.

B. Except as provided in subsections (G) and (H), rolling 12-month average mercury emissions from an electric generating plant shall not exceed 10 percent of inlet mercury or 0.0087 pound per gigawatt-hour, whichever is greater. Mercury emissions from an electric generating unit, when averaged with emissions from other electric generating units at the same electric generating plant, shall comply with this limit for the 12 calendar months ending on the later of the following, and each subsequent 12-calendar month period:

1. December 31, 2013 2016; or

2. Twelve full calendar months after the electric generating unit starts commercial operation.

C. The Director shall determine compliance with the emission standards in subsection (B), the emission level established under subsection (H)(7), and the emission limit established under subsection (I) according to the method set forth at 40 CFR § 60.50a(h), as of July 1, 2006 (and no future amendments or editions), which is incorporated by reference and on file with the Department.

D. The owner or operator of an electric generating plant subject to this Section shall measure, record, and report the mercury in the exhaust gases according to 40 CFR §§ 60.49a(p), 60.4170-60.4176, and 40 CFR Part 75, Subpart I, as of July 1, 2006 (and no future amendments or editions), which are incorporated by reference and on file with the Department.

E. By January 1, 2008, the owner or operator of an electric generating plant that commenced construction before that date shall submit an application for a significant permit revision under R18-2-320 to incorporate the monitoring, recordkeep-ing and reporting requirements of subsections (C) and (D) into the plant's permit.

F. By January 1, 2009, the owner or operator of an electric generating plant that commenced construction before that date shall submit an application for a significant permit revision under R18-2-320 to incorporate the emission standards in subsection (B) into the plant's permit. The application shall include a control strategy for meeting the emission standards and a demonstration that the control strategy is projected to meet the standards.

G. An electric generating plant shall be exempt from the standard in subsection (B) until November 30, 2014, if:

1. The owner or operator of the electric generating plant installs and operates control technology or boiler technology or follows practices projected to meet the standard in subsection (B) according to the control strategy approved as part of the electric generating plant's permit;

2. The owner or operator operates and maintains the electric generating plant, including any associated air pollution control equipment, in a manner consistent with good air pollution control practices for minimizing mercury emissions;

3. The control strategy fails to result in emissions meeting the standard in subsection (B);

4. By January 31, 2014, the owner or operator notifies the Department of the failure to comply with subsection (B) and of the owner or operator's intent to qualify for an exemption under this subsection or subsection (H); and

5. Emissions of mercury from the electric generating plant comply with subsection (B) by no later than December 31, 2014.

H. An electric generating plant shall be exempt from the standard in subsection (B) if:

1. The owner or operator of the electric generating plant installs and operates control technology or boiler technology or follows practices projected to meet the standard in subsection (B) according to the control strategy approved as part of the electric generating plant's permit;

2. The owner or operator operates and maintains the electric generating plant, including any associated air pollution control equipment, in a manner consistent with good air pollution control practices for minimizing mercury emissions;

3. The control strategy fails to result in emissions meeting the standard in subsection (B);

4. By January 31, 2014, the owner or operator notifies the Department of the failure to comply with subsection (B) and of the owner or operator's intent to qualify for an exemption under this subsection or subsection (G); and

5. By December 31, 2014, the owner or operator files an application for a significant permit revision containing an analysis of the incremental best available control technology;

6. The Department does not deny the application for a permit revision filed under subsection (5); and

7. From January 1, 2014, until the end of the 35th full calendar month after the Department issues a permit revision under subsection (I), rolling 12-month mercury emissions from the electric generating plant do not exceed the greater of the following amounts as measured for the plant during calendar year 2013:

a. The percentage of inlet mercury actually emitted minus 10 percent of the percentage control achieved; or

b. Actual mercury emissions in pounds per gigawatt-hour plus 10 percent.

I. A permit revision issued in response to an application submitted under subsection (H)(5) shall impose incremental best available control technology. Beginning at the end of the 36th full calendar month after the Department issues a permit revision under this subsection, rolling 12-month mercury emissions from the electric generating plant shall not exceed the emission limit imposed under this subsection.

J. After December 31, 2015, any best available control technology analysis for a new electric generating unit conducted under R18-2-406 shall consider alternative technologies for combustion of coal and coal-derived fuels. This subsection does not diminish the Department's authority under R18-2-406 .

Notes

Ariz. Admin. Code § R18-2-734

New Section made by final rulemaking at 12 A.A.R. 4701, effective January 29, 2007 (Supp. 06-4). Amended by Final rulemaking at 21 A.A.R. 711, effective 6/30/2015.