• .. 

REDLINE/STRIKEOUT SUMMARY VERSION 

FOR INFORMATIONAL PURPOSES ONLY 

EPA PENDING SIP APPROVALS - CHAPTER SECTIONS 4 13 

AND 14- R-18 (5/11/2011), AND 

Permitting Requirements 

CHAPTER6 

Section 4. Prevention of significant deterioration. 

(a) Definitions. For purposes of this section: 

"Actual emissions" means the actual rate of emissions of a regulated NSR 

pollutant from an emissions unit, as determined in accordance with paragraphs (i) 

through (iii) of this definition, except that this definition shall not apply for calculating 

whether a significant emissions increase has occurred, or for establishing a PAL under 

paragraph (b)(xv) of this section. Instead, the definitions for "Projected actual emissions" 

and "Baseline actual emissions" of this section shall apply for those purposes. 

(i) In general, actual emissions as of a particular date shall equal the 

average rate, in tons per year, at which the unit actually emitted the pollutant during a 

consecutive 24-month period which precedes the particular date and which is 

representative of normal source operation. The Division shall allow the use of a different 

time period upon a determination that it is more representative of normal source 

operation. Actual emissions shall be calculated using the unit's actual operating hours, 

production rates, and types of materials processed, stored, or com busted during the 

selected time period. 

(ii) The Division may presume that source-specific allowable emissions 

for the unit are equivalent to the actual emissions of the unit. 

(iii) For any emissions unit that has not begun normal operations on the 

particular date, actual emissions shall equal the potential to emit of the unit on that date. 

"Administrator" means Administrator of the Division of Air Quality, Wyoming 

Department of Environmental Quality. 

"Allowable emissions" means the emission rate of a stationary source calculated 

using the maximum rated capacity of the source (unless the source is subject to 

enforceable permit conditions which limit the operating rate or hours of operation, or 

both) and the most stringent of the following: 

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(i) Applicable standards set forth in Chapter 5, Section 2 or Section 3 of 

these regulations and other new source performance standards and national emission 

standards for hazardous air pollutants promulgated by the EPA but not yet adopted by the 

State of Wyoming. 

(ii) Any other applicable emission limit in these regulations. 

(iii) The emission rate agreed to by the owner or operator as an 

enforceable permit condition. 

"Baseline actual emissions" means the rate of emissions, in tons per year, of a 

regulated NSR pollutant, as determined in accordance with paragraphs (i) through (iv) of 

this definition. 

(i) For any existing electric utility steam generating unit, baseline actual 

emissions means the average rate, in tons per year, at which the unit actually emitted the 

pollutant during any consecutive 24-month period selected by the owner or operator 

within the 5-year period immediately preceding when the owner or operator begins actual 

construction of the project. The Division shall allow the use of a different time period 

upon a determination that it is more representative of normal source operation. 

(A) The average rate shall include fugitive emissions to the extent 

quantifiable, and emissions associated with startups, shutdowns, and malfunctions. 

(B) The average rate shall be adjusted downward to exclude any 

non-compliant emissions that occurred while the source was operating above an emission 

limitation that was legally enforceable during the consecutive 24-month period. 

(C) For a regulated NSR pollutant, when a project involves 

multiple emissions units, only one consecutive 24-month period must be used to 

determine the baseline actual emissions for the emissions units being changed. A 

different consecutive 24-month period can be used for each regulated NSR pollutant. 

(D) The average rate shall not be based on any consecutive 24-

month period for which there is inadequate information for determining annual 

emissions, in tons per year, and for adjusting this amount if required by paragraph (i)(B) 

of this definition. 

(ii) For an existing emissions unit (other than an electric utility steam 

generating unit), baseline actual emissions means the average rate, in tons per year, at 

which the emissions unit actually emitted the pollutant during any consecutive 24-month 

period selected by the owner or operator within the 1 0-year period immediately preceding 

either the date the owner or operator begins actual construction of the project, or the date 

a complete permit application is received by the Division for a Chapter 6, Section 4 

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permit, whichever is earlier, except that the 10-year period shall not include any period 

earlier than November 15, 1990. 

(A) The average rate shall include fugitive emissions to the extent 

quantifiable, and emissions associated with startups, shutdowns, and malfunctions. 

(B) The average rate shall be adjusted downward to exclude any 

non-compliant emissions that occurred while the source was operating above an emission 

limitation that was legally enforceable during the consecutive 24-month period. 

(C) The average rate shall be adjusted downward to exclude any 

emissions that would have exceeded an emission limitation with which the major 

stationary source must currently comply, had such major stationary source been required 

to comply with such limitations during the consecutive 24-month period; however, if an 

emission limitation is part of a maximum achievable control technology standard that the 

EPA Administrator proposed or promulgated under 40 CFR 63, the baseline actual 

emissions need only be adjusted if the Division has taken credit for such emissions 

reductions in an attainment demonstration or maintenance plan consistent with the 

requirements of 40 CFR 51.165(a)(3)(ii)(G). 

(D) For a regulated NSR pollutant, when a project involves 

multiple emissions units, only one consecutive 24-month period must be used to 

determine the baseline actual emissions for the emissions units being changed. A 

different consecutive 24-month period can be used for each regulated NSR pollutant. 

(E) The average rate shall not be based on any consecutive 24-

month period for which there is inadequate information for determining annual 

emissions, in tons per year, and for adjusting this amount if required by paragraphs (ii)(B) 

and (C) of this definition. 

(iii) For a new emissions unit, the baseline actual emissions for purposes 

of determining the emissions increase that will result from the initial construction and 

operation of such unit shall equal zero; and thereafter, for all other purposes, shall equal 

the unit's potential to emit. 

(iv) For a PAL for a stationary source, the baseline actual emissions shall 

be calculated for existing electric utility steam generating units in accordance with the 

procedures contained in paragraph (i) of this definition, for other existing emissions units 

in accordance with the procedures contained in paragraph (ii) of this definition, and for a 

new emissions unit in accordance with the procedures contained in paragraph (iii) of this 

definition. · 

"Baseline area" means any intrastate area (and every part thereof) designated as 

attainment or unclassifiable under the Federal Clean Air Act in which a major source or 

major modification establishing the minor source baseline date would construct or would 

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(i) The following baseline areas have been designated as separate 

particulate matter attainment areas under section 107 of the Clean Air Act: 

(A) The Powder River Basin Area, described as that area bounded 

by Township 40 through 52 North, and Range 69 through 73 West, inclusive ofthe Sixth 

Principal Meridian, Campbell and Converse Counties, excluding the areas defined as the 

Pacific Power and Light attainment area and the Hampshire Energy attainment area. 

(B) The Pacific Power and Light Area, described as that area 

bounded by the NWY4 of Section 27, T50N, R71 W, Campbell County, Wyoming. 

(C) The Hampshire Energy Area, described as that area bounded 

by Section 6 excluding the SWY4; E\12 Section 7; Section 17 excluding the SWY4; Section 

14 excluding the SEY4; Sections 2, 3, 4, 5, 8, 9, 10, 11, 15, 16 ofT48N, R70W and 

Section 26 excluding the NEY4; SWY4 Section 23; Sections 19, 20, 21, 22, 27, 28, 29, 30, 

31, 32, 33, 34,35 ofT49N, R70W, Campbell County, Wyoming. 

(D) The Kennecott-Puron Area, described as the area bounded by 

the WY2SWY4 Section 18, WY2NWY4, NWY4SWY4 Section 19, T47N, R70W, S\12 Section 

13, N\12, NY2SWY4, NY2SEY4 Section 24 T47N, R71 W, Campbell County, Wyoming. 

(E) The remainder of the State of Wyoming. 

(ii) Any baseline area established originally for the TSP increments shall 

remain in effect and shall apply for purposes of determining the amount of available 

PM10 increments. 

"Baseline concentration" means that ambient concentration level which exists in 

the baseline area at the time of the applicable minor source baseline date. A baseline 

concentration is determined for each pollutant for which a minor source baseline date is 

established and shall include: 

(i) The actual emissions, as defined in this section, representative of 

sources in existence on the applicable minor source baseline date, except as provided in 

paragraph (iv) of this definition; 

(ii) The allowable emissions of major stationary sources which 

commenced construction before the major source baseline date, but were not in operation 

by the applicable minor source baseline date; 

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(iii) Contributions due to emissions from any emitting source or 

modification which (1) is not listed in Chapter 6, Section 4(a) under the definition for 

"Major stationary source", item (a) and qualified as "major" prior to August 7, 1980 only 

because fugitive emissions were included in determining potential to emit, (2) submitted 

a complete permit application under Chapter 6, Section 4(b) or the Federal Clean Air Act 

prior to August 7, 1980, and (3) was in existence as ofthe minor source baseline date; 

(iv) The following will not be included in the baseline concentration and 

will affect the applicable maximum allowable increment: 

(A) Actual emissions, as defined in this section, from any major 

stationary source on which construction commenced after the major source baseline date; 

and 

(B) Actual emissions increases and decreases, as determined in 

accordance with the definition for "Actual emissions" in this section, at any stationary 

source occurring after the minor source baseline date. 

"Begin actual construction" means, in general, initiation of physical on-site 

construction activities on an emissions unit which are of a permanent nature. Such 

activities include, but are not limited to, installation of building supports and foundations, 

laying of underground pipework, and construction of permanent storage structures. With 

respect to a change in method of operation this term refers to those onsite activities, other 

than preparatory activities, which mark the initiation of the change. 

"Best available control technology" means an emission limitation (including a 

visible emission standard) based on the maximum degree of reduction of each pollutant 

subject to regulation under these Standards and Regulations or regulation under the 

Federal Clean Air Act, which would be emitted from or which results for any proposed 

major stationary source or major modification which the Administrator, on a case-by-case 

basis, taking into account energy, environmental, and economic impacts and other costs, 

determines is achievable for such source or modification through application or 

production processes and available methods, systems, and techniques, including fuel 

cleaning or treatment or innovative fuel combustion techniques for control of such 

pollutant. If the Administrator determines that technological or economic limitations on 

the application of measurement methodology to a particular emissions unit would make 

the imposition of an emission standard infeasible, he may instead prescribe a design, 

equipment, work practice or operational standard or combination thereof to satisfy the 

requirement of Best Available Control Technology. Such standard shall, to the degree 

possible, set forth the emission reduction achievable by implementation of such design, 

equipment, work practice, or operation and shall provide for compliance by means which 

achieve equivalent results. Application of BACT shall not result in emissions in excess 

ofthose allowed under Chapter 5, Section 2 or Section 3 of these regulations and any 

other new source performance standard or national emission standards for hazardous air 

pollutants promulgated by the EPA but not yet adopted by the State of Wyoming. 

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"Clean coal technology" means any technology, including technologies applied 

at the precombustion, combustion, or post combustion stage, at a new or existing facility 

which will achieve significant reduction in air emissions of sulfur dioxide or oxides of 

nitrogen associated with the utilization of coal in the generation of electricity, or process 

steam which was not in widespread use as ofNovember 15, 1990. 

"Clean coal technology demonstration project" means a project using funds 

appropriated under the heading "Department of Energy-Clean Coal Technology", up to a 

total amount of $2,500,000,000 for commercial demonstration of clean coal technology, 

or similar projects funded through appropriations for the Environmental Protection 

Agency. The Federal contribution for a qualifying project shall be at least 20 percent of 

the total cost of the demonstration project. 

"Commenced", as applied to construction of a major stationary source or major 

modification, means that the owner or operator has obtained a Construction Permit 

required by Chapter 6, Section 2 and either has (i) begun, or caused to begin, a 

continuous program of actual on-site construction of the source or (ii) entered into 

binding agreements or contractual obligations, which cannot be canceled or modified 

without substantial loss to the owner or operator, to undertake a program of construction 

of the source to be completed within a reasonable time. 

"Complete" means, in reference to an application for a permit, that the application 

contains all the information necessary for processing the application. Designating an 

application complete for purposes of permit processing does not preclude the Division 

from requesting or accepting any additional information. 

"Construction" means any physical change or change in the method of operation 

(including fabrication, erection, installation, demolition, or modification of an emissions 

unit) which would result in a change in emissions. 

"Continuous emissions monitoring system (CEMS)" means all of the equipment 

that may be required to meet the data acquisition and availability requirements of this 

section, to sample, condition (if applicable), analyze, and provide a record of emissions 

on a continuous basis. 

"Continuous emissions rate monitoring system (CERMS)" means the total 

equipment required for the determination and recording of the pollutant mass emissions 

rate (in terms of mass per unit oftime). 

"Continuous parameter monitoring system (CPMS)" means all of the equipment 

necessary to meet the data acquisition and availability requirements of this section, to 

monitor process and control device operational parameters (for example, control device 

secondary voltages and electric currents) and other information (for example, gas flow 

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rate, 0 2 or C02 concentrations), and to record average operational parameter value(s) on 

a continuous basis. 

"Electric utility steam generating unit" means any steam electric generating unit 

that is constructed for the purpose of supplying more than one-third of its potential 

electric output capacity and more than 25 MW electrical output to any utility power 

distribution system for sale. Any steam supplied to a steam distribution system for the 

purpose of providing steam to a steam-electric utility steam generator that would produce 

electrical energy for sale is also considered in determining the electrical energy output 

capacity of the affected facility. 

"Emissions unit" means any part of a stationary source that emits or would have 

the potential to emit any regulated NSR pollutant and includes an electric utility steam 

generating unit as defined in this section. For purposes of this section, there are two 

types of emissions units as described in paragraphs (i) and (ii) of this definition. 

(i) A new emissions unit is any emissions unit that is (or will be) newly 

constructed and that has existed for less than 2 years from the date such emissions unit 

first operated. 

(ii) An existing emissions unit is any emissions unit that does not meet the 

requirements in paragraph (i) of this definition. 

"Enforceable" means all limitations and conditions which are enforceable under 

provisions of the Wyoming Environmental Quality Act and/or are federally enforceable 

by the Administrator of the EPA, including those requirements developed pursuant to 40 

CFR parts 60 and 61, requirements within the State Implementation Plan, and any permit 

requirements established pursuant to 40 CFR 52.21 or under regulations approved 

pursuant to 40 CFR 51.18 or 51.166. 

"Federal Land Manager" means, with respect to any lands in the United States, 

the Secretary of the Department with authority over such lands. 

"Fugitive emissions" means those emissions which could not reasonably pass 

through a stack, chimney, vent, or other functionally equivalent opening. 

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• 

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"High terrain" means any area having an elevation 900 feet or more above the 

base of the stack of a source. 

"Indian Governing Body" means the governing body of any tribe, band, or group 

of Indians subject to the jurisdiction of the United States and recognized by the United 

States as possessing power of self-Government. 

"Indian Reservation" means any federally recognized reservation established by 

treaty, agreement, executive order, or act of Congress. 

"Innovative control technology" means any system of air pollution control that 

has not been adequately demonstrated in practice, but would have a substantial likelihood 

of achieving greater continuous emissions reduction than any control system in current 

practice or of achieving at least comparable reductions at lower cost in terms of energy, 

economics, or non air quality environmental impacts. 

"Lowest achievable emission rate (LAER)" means, for any source, the more 

stringent rate of emissions based on the following: 

(i) The most stringent emissions limitation which is contained in the 

implementation plan of any State for such class or category of stationary source, unless 

the owner or operator of the proposed stationary source demonstrates that such 

limitations are not achievable; or 

(ii) The most stringent emissions limitation which is achieved in practice 

by such class or category of stationary sources. This limitation, when applied to a 

modification, means the lowest achievable emissions rate for the new or modified 

emissions units within a stationary source. In no event shall the application of the term 

permit a proposed new or modified stationary source to emit any pollutant in excess of 

the amount allowable under an applicable new source standard of performance. 

"Low terrain" means any area other than high terrain. 

"Major modification" means any physical change in or change in the method of 

operation of a major stationary source that would result in: a significant emissions 

increase (as defined in the definition for "Significant emissions increase" in this section) 

of a regulated NSR pollutant (as defined in the definition for "Regulated NSR pollutant" 

in this section); and a significant net emissions increase of that pollutant from the major 

stationary source. Any significant emissions increase (as defined in the definition for 

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"Significant emissions increase" in this section) from any emissions units or net 

emissions increase (as defined in the definition for "Net emissions increase" in this 

section) at a major stationary source that is significant for volatile organic compounds or 

NOx shall be considered significant for ozone. 

(i) A physical change or change in the method of operation shall not 

include: 

(A) Routine maintenance, repair and replacement. 

(B) Use of an alternative fuel by reason of an order under section 

125 of the Federal Clean Air Act; 

(C) An increase in the hours of operation or in the production rate, 

if such increase does not exceed the operating design capacity of the major stationary 

source unless such change would be prohibited by, or inconsistent with, an enforceable 

permit issued by the Division; 

(D) Use of an alternative fuel or raw material by reason of an 

order in effect under sections 2(a) and (b) of the Energy Supply and Environmental 

Coordination Act of 1974 (or any superseding legislation), or by reason of a natural gas 

curtailment plan in effect pursuant to the Federal Power Act; 

(E) Use of an alternative fuel or raw material, if prior to January 6, 

1975, the source was capable of accommodating such fuel or material unless such change 

would be prohibited by, or inconsistent with, an enforceable permit issued by the 

Division, or if the source is approved to use such fuel or material through an enforceable 

permit issued under these regulations; 

(F) Change in ownership of the stationary source; 

(G) The use of municipal solid waste as an alternative fuel at a 

steam generating plant; 

(H) The installation, operation, cessation or removal of a 

temporary clean coal technology demonstration project, provided that the project 

complies with: 

(I) The Wyoming State Implementation Plan, and 

(II) Other requirements necessary to attain and maintain 

the national ambient air quality standards during the project and after it is terminated. 

(I) The installation or operation of a permanent clean coal 

technology demonstration project that constitutes repowering, provided that the project 

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does not result in an increase in the potential to emit of any regulated pollutant emitted by 

the unit. This exemption shall apply on a pollutant-by-pollutant basis. 

(J) The reactivation of a very clean coal-fired electric utility steam 

generating unit. 

(ii) This definition shall not apply with respect to a particular regulated 

NSR pollutant when the major stationary source is complying with the requirements 

under paragraph (b)(xv) of this section for a PAL for that pollutant. Instead, the 

definition in paragraph (b)(xv)(B) for "PAL major modification" of this section shall 

apply. 

"Major source baseline date" means: 

(i) In the case of and sulfur dioxide, January 6, 

1975;and 

(ii) In the case of nitrogen dioxide, February 8, 1988. 

"Major stationary source" means (a) any of the following stationary sources of 

air pollutants which emit, or have the potential to emit, one hundred tons per year or more 

of any air pollutant for which standards are established under these Standards and 

......... ~u ..... ·, Jll" or under the Federal Clean Air 

fossil fuel-fired steam electric plants of more than 

two hundred and fifty million British thermal units per hour heat input, coal cleaning 

plants (with thermal dryers), kraft pulp mills, Portland Cement plants, primary zinc 

smelters, iron and steel mill plants, primary aluminum ore reduction plants (with thermal 

dryers), primary copper smelters, municipal incinerators capable of charging more than 

two hundred and fifty tons of refuse per day, hydrofluoric, sulfuric, and nitric acid plants, 

petroleum refineries, lime plants, phosphate rock processing plants, coke oven batteries, 

sulfur recovery plants, carbon black plants (furnace process), primary lead smelters, fuel 

conversion plants, sintering plants, secondary metal production plants, chemical process 

plants (which does not include ethanol production facilities that produce ethanol by 

natural fermentation included in NAICS codes 325193 or 312140), fossil fuel boilers (or 

combinations thereof) of more than two hundred and fifty million British thermal units 

per hour heat input, petroleum storage and transfer plants with a capacity exceeding three 

hundred thousand barrels, taconite ore processing plants, glass fiber processing plants, 

charcoal production plants. (b) Such term also includes any stationary source which 

emits, or has the potential to emit, two hundred and fifty tons per year or more of any air 

pollutant for which standards are established under these Standards and · 

under the Federal Clean Air 

(c) Such term also includes any physical change that would occur 

at a stationary source not otherwise qualifying under this definition if the change would 

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constitute a major stationary source by itself. (d) A major source which is 

volatile or NOx is considered to be for ozone. 

"Minor source baseline date" means the earliest date after August 7, 1977 for 

and sulfur · · and after February 8, 1988 for nitrogen 

oxides, on which a major stationary source or major 

modification submits a complete permit application under Chapter 6, Section 4(b) or 

under the Federal Clean Air Act. 

(i) The minor source baseline date for sulfur dioxide for the State of 

Wyoming is February 2, 1978. 

(ii) The minor source baseline date for nitrogen oxides for the State of 

Wyoming is February 26, 1988. 

(iii) The minor source baseline date for is as 

follows: 

(A) For the Powder River Basin Area- March 6, 1997; 

(B) For the Pacific Power and Light Area- June 18 1980; 

(C) For the Hampshire Energy Area- September 30, 1982; 

(D) For the Kennecott-Puron Area- February 27, 1995; 

(E) For the rest of the State of Wyoming- February 22, 1979. 

(iv) The baseline date is established for each pollutant for which 

increments or other equivalent measures have been established, if: 

(A) The area in which the proposed source or modification would 

construct is designated as attainment or unclassifiable under the Federal Clean Air Act 

for the pollutant on the date of its complete application; and 

(B) In the case of a major stationary source, the pollutant would be 

emitted in significant amounts, or in the case of a major modification, there would be a 

significant net emissions increase of the pollutant. 

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(v) The baseline date is not established by the permit application for an 

emitting source or modification which (1) is not listed in Chapter 6, Section 4(a) under 

the definition for "Major stationary source", item (a), (2) qualified as "major" prior to 

August 7, 1980 only because fugitive emissions were included in determining potential to 

emit, and (3) submitted a complete permit application under Chapter 6, Section 4(b) or 

the Federal Clean Air Act prior to August 7, 1980. 

(vi) Any minor source baseline date established originally for the TSP 

increments shall remain in effect and shall apply for purposes of determining the amount 

of available PM10 increments. 

"Net emissions increase" means, with respect to any regulated NSR pollutant 

emitted by a major stationary source, the amount by which the sum of the following 

exceeds zero: 

(i) The increase in emissions from a particular physical change or change 

in the method of operation at a stationary source as calculated pursuant to paragraph 

(b)(i)(J) ofthis section; 

(ii) Any other increases and decreases in actual emissions at the major 

stationary source that are contemporaneous with the particular change and are otherwise 

creditable. Baseline actual emissions for calculating increases and decreases under this 

paragraph (ii) shall be determined as provided in the definition for "Baseline actual 

emissions", except that paragraphs (i)(C) and (ii)(D) of the definition for "Baseline actual 

emissions" shall not apply. 

(iii) An increase or decrease in actual emissions is contemporaneous with 

the increase from the particular change only if it occurs between: 

(A) The date five years before construction on the particular 

change commences; and 

(B) The date that the increase from the particular change occurs. 

(iv) An increase or decrease in actual emissions is creditable only if: 

(A) The Division has not relied on it in issuing a Chapter 6, 

Section 4 permit for the source, which is in effect when the increase in actual emissions 

from the particular change occurs. 

(v) An increase or decrease in actual emissions of sulfur dioxide, 

particulate matter, or nitrogen oxides that occurs before the applicable minor source 

baseline date is creditable only if it is required to be considered in calculating the amount 

of maximum allowable increases remaining available. 

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(vi) An increase in actual emissions is creditable only to the extent that 

the new level of actual emissions exceeds the old level. 

(vii) A decrease in actual emissions is creditable only to the extent that: 

(A) The old level of actual emissions or the old level of allowable 

emissions, whichever is lower, exceeds the new level of actual emissions; 

(B) It is enforceable as a practical matter at and after the time that 

actual construction on the particular change begins; 

(C) It has approximately the same qualitative significance for 

public health and welfare as that attributed to the increase from the particular change; and 

(viii) An increase that results from a physical change at a source occurs 

when the emissions unit on which construction occurred becomes operational and begins 

to emit a particular pollutant. Any replacement unit that requires shakedown becomes 

operational only after a reasonable shakedown period, not to exceed 180 days. 

(ix) The definition of"Actual emissions" of this section, shall not apply 

for determining creditable increases and decreases. 

"Potential to emit" means the maximum capacity of a stationary source to emit a 

pollutant under its physical and operational design. Any physical or operational 

limitation on the capacity of the source to emit a pollutant, including air pollution control 

equipment and restrictions on hours of operation or the type or amount of material 

combusted, stored, or processed, shall be treated as part of its design ifthe limitation or 

the affect it would have on emissions is enforceable. Secondary emissions do not count 

in determining the potential to emit of a stationary source. 

"Predictive emissions monitoring system (PEMS)" means all of the equipment 

necessary to monitor process and control device operational parameters (for example, 

control device secondary voltages and electric currents) and other information (for 

example, gas flow rate, 02 or C02 concentrations), and calculate and record the mass 

emissions rate (for example, lb/hr) on a continuous basis. 

"Project" means a physical change in, or change in method of operation of, an 

existing major stationary source. 

"Projected actual emissions" means the maximum annual rate, in tons per year, 

at which an existing emissions unit is projected to emit a regulated NSR pollutant in any 

one of the 5 years (12-month period) following the date the unit resumes regular 

operation after the project, or in any one of the 10 years following that date, if the project 

involves increasing the emissions unit's design capacity or its potential to emit that 

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regulated NSR pollutant, and full utilization of the unit would result in a significant 

emissions increase, or a significant net emissions increase at the major stationary source. 

(i) In determining the projected actual emissions under the above 

paragraph of this section (before beginning actual construction), the owner or operator of 

the major stationary source: 

(A) Shall consider all relevant information, including but not 

limited to, historical operational data, the company's own representations, the company's 

expected business activity and the company's highest projections of business activity, the 

company's filings with the State or Federal regulatory authorities, and compliance plans 

approved by the Division; 

(B) Shall include fugitive emissions to the extent quantifiable and 

emissions associated with startups, shutdowns, and malfunctions; 

(C) Shall exclude, in calculating any increase in emissions that 

results from the particular project, that portion of the unit's emissions following the 

project that an existing unit could have accommodated during the consecutive 24-month 

period used to establish the baseline actual emissions under the definition for "Baseline 

actual emissions" of this section and that are also unrelated to the particular project, 

including any increased utilization due to product demand growth; or, 

(D) In lieu of using the method set out in paragraphs (i)(A) 

through (C) of this definition, may elect to use the emissions unit's potential to emit, in 

tons per year, as defined under the definition of "Potential to emit" of this section. 

"Reactivation of a very clean coal-fired electric utility steam generating unit" 

means any physical change or change in the method of operation associated with the 

commencement of commercial operations by a coal-fired utility unit after a period of 

discontinued operation where the unit: 

(i) Has not been in operation for the two-year period prior to the 

enactment of the Clean Air Act Amendments of 1990, and the emissions from such unit 

continue to be carried in the State of Wyoming's emissions inventory at the time of 

enactment; 

(ii) Was equipped prior to shut-down with a continuous system of 

emissions control that achieves a removal efficiency for sulfur dioxide of no less than 85 

percent and a removal efficiency for particulates of not less than 98 percent; 

(iii) Is equipped with low-NOx burners prior to the time of 

commencement of operations following reactivation; and 

(iv) Is otherwise in compliance with the requirements of the Clean Air 

Act. 

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"Regulated NSR pollutant", for purposes of this section, means the following: 

(i) Any pollutant for which a national ambient air quality standard has 

been promulgated and any pollutant identified under this paragraph as a constituent or 

precursor to such pollutant. Precursors identified by the EPA Administrator for purposes 

ofNSR are the following: 

(A) Volatile organic compounds and nitrogen oxides are 

precursors to ozone in all attainment and unclassifiable areas. 

(B) Sulfur dioxide is a precursor to PM2.s in all attainment and 

unclassifiable areas. 

(C) Nitrogen oxides are presumed to be precursors to PM2.5 in all 

attainment and unclassifiable areas, unless the State demonstrates to the EPA 

Administrator's satisfaction or EPA demonstrates that emissions of nitrogen oxides from 

sources in a specific area are not a significant contributor to that area's ambient PM2.5 

concentrations. 

(D) Volatile organic compounds are presumed not to be precursors 

to PM2.5 in any attainment or unclassifiable area, unless the State demonstrates to the 

EPA Administrator's satisfaction or EPA demonstrates that emissions of volatile organic 

compounds from sources in a specific area are a significant contributor to that area's 

ambient PM2.s concentrations. 

(ii) Any pollutant that is subject to any standard promulgated under 

section Ill of the Federal Clean Air Act; 

(iii) Any Class I or II substance subject to a standard promulgated under 

or established by Title VI of the Federal Clean Air Act; 

(iv) Any pollutant that otherwise is subject to regulation under the Federal 

Clean Air Act; except that any or all hazardous air pollutants either listed in section 112 

of the Federal Clean Air Act or added to the list pursuant to section 112(b)(2) of the 

Federal Clean Air Act, which have not been delisted pursuant to section 112(b)(3) of the 

Federal Clean Air Act, are not regulated NSR pollutants unless the listed hazardous air 

pollutant is also regulated as a constituent or precursor of a general pollutant listed under 

section 108 of the Federal Clean Air Act. 

(v) [Reserved.] 

(vi) Particulate matter (PM) emissions, PM2.5 emissions, and PM10 

emissions shall include gaseous emissions from a source or activity which condense to 

form particulate matter at ambient temperatures. On or after January 1, 2011, such 

6-16 
condensable particulate matter shall be accounted for in applicability determinations and 

in establishing emissions limitations for PM, PM2.s and PM10 in PSD permits. 

Compliance with emissions limitations for PM, PM2.s and PM10 issued prior to this date 

shall not be based on condensable particulate matter unless required by the terms and 

conditions of the permit or the applicable implementation plan. Applicability 

determinations made prior to this date without accounting for condensable particulate 

matter shall not be considered in violation of this section unless the applicable 

implementation plan required condensable particulate matter to be included. 

"Replacement unit" means an emissions unit for which all the criteria listed in 

this section are met. No creditable emission reductions shall be generated from shutting 

down the existing emissions unit that is replaced. 

(i) The emissions unit is a reconstructed unit within the meaning of 

40 CFR part 60.15(b )(1 ), or the emissions unit completely takes the place of an existing 

emissions unit. 

(ii) The emissions unit is identical to or functionally equivalent to the 

replaced emissions unit. 

(iii) The replacement does not change the basic design parameter(s) (as 

discussed in 40 CFR part 51.166(y)(2)) of the process unit. 

(iv) The replaced emissions unit is permanently removed from the major 

stationary source, otherwise permanently disabled, or permanently barred from operation 

by a permit that is enforceable as a practical matter. If the replaced emissions unit is 

brought back into operation, it shall constitute a new emissions unit. 

"Repowering" means replacement of an existing coal-fired boiler with one of the 

following clean coal technologies: atmospheric or pressurized fluidized bed combustion, 

integrated gasification combined cycle, magnetohydrodynamics, direct and indirect coalfired turbines, integrated gasification fuel cells, or as determined by the Administrator of 

EPA, in consultation with the Secretary of Energy, a derivative of one or more of these 

technologies, and any other technology capable of controlling multiple combustion 

emissions simultaneously with improved boiler or generation efficiency and with 

significantly greater waste reduction relative to the performance of technology in 

widespread commercial use as ofNovember 15, 1990. 

(i) Repowering shall also include any oil and/or gas-fired unit which has 

been awarded clean coal technology demonstration funding as of January 1, 1991, by the 

Department of Energy. 

(ii) The Administrator shall give expedited consideration to permit 

applications for any source that satisfies the requirements of this subsection and is 

granted an extension under section 409 of the Clean Air Act. 

6-17 
"Secondary emissions" means emissions which occur as a result of the 

construction or operation of a major stationary source or major modification, but do not 

come from the major stationary source or major modification itself. For the purposes of 

this section, secondary emissions must be specific, well defined, quantifiable, and impact 

the same general areas as the stationary source or modification which causes the 

secondary emissions. Secondary emissions include emissions from any offsite support 

facility which would not be constructed or increase its emissions except as a result of the 

construction or modification of the major stationary source or major modification. 

Secondary emissions do not include any emissions which come directly from a mobile 

source, such as emissions from the tailpipe of a motor vehicle or from a train. 

"Significant" means: 

(i) In reference to a net emissions increase or the potential of a source to 

emit any of the following pollutants, a rate of emissions that would equal or exceed any 

of the following rates: 

POLLUTANT AND EMISSIONS RATE 

Carbon monoxide: 

Nitrogen oxides: 

Sulfur dioxide: 

Particulate matter: 

PM2.s: 

Ozone: 

Lead: 

Fluorides: 

Sulfuric acid mist: 

Hydrogen sulfide (H2S): 

Total reduced sulfur (including H2S): 

Reduced sulfur compounds (including H2S): 

Municipal waste combustor organics 

(measured as total tetra- through octa-chlorinated 

dibenzo-p-dioxins and dibenzofurans): 

6-18 

1 00 tons per year ( tpy) 

40tpy 

40tpy 

25 tpy of particulate matter 

emissions; 15 tpy ofPM10 emissions 

10 tpy of direct PM2.s emissions; 

40 tpy of sulfur dioxide emissions; 

40 tpy of nitrogen oxide emissions 

unless demonstrated not to be a 

PM2.s precursor under the definition 

of "Regulated NSR pollutant" in 

Section 4(a) of this chapter 

40 tpy of volatile organic compounds 

or nitrogen oxides 

0.6 tpy 

3 tpy 

7 tpy 

10 tpy 

10 tpy 

10 tpy 

3.2 x 10-6 megagrams per year (3.5 

x 10-6 tons per year) 
Municipal waste combustor metals 

(measured as particulate matter): 

Municipal waste combustor acid gases 

I4 megagrams per year ( I5 tons per 

year) 

(measured as sulfur dioxide and hydrogen chloride):36 megagrams per year (40 tons per 

year) 

Municipal solid waste landfill emissions 

(measured as nonmethane organic compounds): 45 megagrams per year (50 tons per 

year) 

(ii) "Significant" means, in reference to a net emissions increase or the 

potential of a source to emit a pollutant subject to these regulations and regulations under 

the Clean Air Act, that paragraph (i) above does not list, any emissions rate. 

(iii) Notwithstanding paragraph (i) above, "significant" means any 

emissions rate or any net emissions increase associated with a major stationary source or 

major modification which would construct within I 0 kilometers of a Class I Area, and 

have an impact on such area equal to or greater than I J.tg/m3 (24-hour average). 

"Significant emissions increase" means, for a regulated NSR pollutant, an 

increase in emissions that is significant (as defined in paragraph (i) of the definition of 

"Significant" in this section) for that pollutant. 

"Stationary source" means any structure, building, facility, equipment, 

installation or operation (or combination thereof) which emits or may emit any air 

pollutant subject to these regulations or regulations under the Federal Clean Air Act. 

"Structure, building, facility, equipment, installation, or operation" means all of 

the pollutant-emitting activities which belong to the same industrial grouping, are located 

on one or more contiguous or adjacent properties, and are under the control of the same 

person (or persons under common control) except the activities of any vessel. Pollutantemitting activities shall be considered as part of the same industrial grouping if they 

belong to the same Major Group (i.e., which have the same two-digit code) as described 

in the Standard Industrial Classification Manual, 1972, as amended by the I977 

Supplement (U.S. Government Printing Office stock numbers 4IOI-0066 and 003-005-

00I76-0, respectively). 

"Temporary clean coal technology demonstration project" means a clean coal 

technology demonstration project that is operated for a period of 5 years or less, and 

which complies with the Wyoming State Implementation Plan and other requirements 

necessary to attain and maintain the national ambient air quality standards during the 

project and after it is terminated. 

"Volatile organic compounds (VOCs)" is defined in Chapter 3, Section 6(a) of 

these regulations. 

6-I9 
(b) Any person who plans to construct any major stationary source or undertake a 

major modification of an existing stationary source shall be subject to the conditions 

outlined below. 

(i) (A) (I) The review of the stationary source for the construction 

or modification permit(s) required under Chapter 6, Section 2 of these regulations shall 

apply and shall be expanded so as to include analysis of the predicted impact of the 

allowable and secondary emissions from the stationary source on the ambient air quality 

in areas affected by such emissions. An analysis of the predicted impact of emissions 

from the stationary source is required for all pollutants for which standards have been 

established under these regulations or under the Federal Clean Air Act and which are 

emitted in significant amounts. An analysis of the impact of other pollutants may be 

required by the Administrator. Such analysis shall identify and quantify the impact on 

the air quality in the area of all emissions not included in the baseline concentrations 

including, but not limited to, those emissions resulting from the instant application and all 

other permits issued in the area. The purpose of this analysis is to determine the total 

deterioration of air quality from the baseline concentrations; however, projections of 

deterioration due to general non-stationary source growth in the area predicted to occur 

after the date of application is not required. A permit to construct pursuant to Chapter 6, 

Section 2 shall be issued only if the conditions of Chapter 6, Section 2 are complied with 

and if the predicted impact (over and above the baseline concentration) of emissions 

defined above is less than the maximum allowable increment shown in Table 1 for the 

classification of the area in which the impact is predicted, and if the ambient standard for 

the pollutant(s) is not exceeded. 

Table 1 

Maximum Allowable Increments of Deterioration - J..tg/m3 

Pollutant 

Particulate Matter: 

PM10, annual arithmetic mean 

PM10, 24-hour maximum 

Sulfur Dioxide: 

Annual arithmetic mean 

24-hour maximum* 

3-hour maximum* 

Nitrogen Dioxide 

Annual arithmetic mean 

Class I 

I 

4 

8 

2 

5 

25 

2.5 

Class II 

I 

17 

30 

20 

91 

512 

25 

*Maximum allowable increment may be exceeded once per year at any receptor site. 

6-20 
(II) Notwithstanding the provisions of paragraph 

(b)(i)(A)(I) above, the following concentrations shall be excluded in determining 

compliance with maximum allowable increases: 

(l.) Concentrations attributable to the increase in 

emissions from stationary sources which have converted from the use of petroleum 

products, natural gas, or both by reason of an order in effect under sections 2( a) and (b) 

ofthe Energy Supply and Environmental Coordination Act of 1974 (or any superseding 

legislation) over the emissions from such sources before the effective date of such an 

order. No such exclusion shall apply for more than five years after the later of such 

effective dates; 

(2.) Concentrations attributable to the increase in 

emissions from sources which have converted from using natural gas by reason of natural 

gas curtailment plan in effect pursuant to the Federal Power Act over the emissions from 

such sources before the effective date of such plan. No such exclusion shall apply for 

more than 5 years after the later of such effective date; 

(3.) Concentrations of particulate matter 

attributable to the increase in emissions from construction or other temporary 

emission-related activities of new or modified sources; 

(4.) The increase in concentrations attributable to 

new sources outside the United States over the concentrations attributable to existing 

sources which are included in the baseline concentrations; and 

(5.) Concentrations attributable to the temporary 

increase in emissions of sulfur dioxide, particulate matter, or nitrogen oxides from 

stationary sources as specified below. 

a. The temporary emissions do not occur for 

more than 2 years. 

6-21 
b. The 2-year time period is not renewable. 

c. Such temporary emissions are not eligible 

for exclusion if they would impact a Class I Area or an area where the applicable 

increment is known to be violated or an area where they would cause or contribute to a 

violation of the applicable ambient air quality standard. 

d. At the end of the temporary emission 

time frame, emissions from the stationary source causing these temporary emissions shall 

not exceed those levels occurring at such source prior to such temporary emission. 

(B) In addition to the analyses required under Chapter 6, Section 

4(b)(i)(A) above, 

(I) The owner or operator shall provide an analysis of the 

impairment to visibility, soils and vegetation that would occur as a result of the source or 

modification and general commercial, residential, industrial, and other growth associated 

with the source or modification. The owner or operator need not provide an analysis of 

the impact on vegetation having no significant commercial or recreational value. 

(II) The owner or operator shall provide an analysis of the 

air quality impact projected for the area as a result of general commercial, residential, 

industrial and other growth associated with the source or modification. 

(C) The requirements for demonstration of compliance with 

applicable increments of Chapter 6, Section 4(b)(i)(A)(I), the additional analysis 

requirements of Chapter 6, Section 4(b )(i)(B) and the ambient air quality analysis 

requirements of Chapter 6, Section 4(b )(i)(E) shall not apply to a proposed major 

stationary source or modification with respect to a particular pollutant if the 

Administrator determines that: 

(I) The increase in allowable emissions of that pollutant 

from the stationary source or the net emissions increase of that pollutant from a 

modification would be temporary and would impact no Class I Area and no area where 

an applicable increment is known to be violated; or 

(II) The stationary source was in existence on March 1, 

1978, and that the maximum allowable emission increases only impact Class II Areas, 

and that after application of BACT, the increase in allowable emissions of each pollutant 

would be less than 50 tons per year. 

(D) Fugitive emissions, to the extent quantifiable, will be 

considered in calculating the potential to emit of the stationary source or modification 

only for: 

6-22 
(I) Sources listed in Chapter 6, Section 4(a) under the 

definition of"Major stationary source", item (a). 

(II) Any other stationary source category which, as of 

August 7, 1980, is being regulated under section 111 or 112 of the Clean Air Act. 

(III) And such other sources as the Environmental Quality 

Council may later determine. 

(E) An application subject to this section shall contain an analysis 

of ambient air quality in the area that would be affected by the stationary source or 

modification as required below: 

(I) For each pollutant that the source would have the 

potential to emit in a significant amount. 

(II) For the modification, each pollutant for which it would 

result in a significant net emissions increase. 

(III) For pollutants for which National Ambient Air 

Quality Standards have been established, the analysis shall contain continuous air quality 

monitoring data gathered for purposes of determining whether emissions of that pollutant 

would cause or contribute to a violation of the standard or any maximum allowable 

increase. 

(IV) In general, the required continuous air quality 

monitoring data shall have been gathered over a period of one year immediately 

preceding receipt of the application. The Administrator may provide that the monitoring 

period specification may be reduced to a minimum of four months if he is satisfied that a 

complete and adequate analysis can be accomplished with monitoring data gathered over 

a period shorter than one year. 

(V) All monitoring conducted pursuant to the requirements 

of this section shall meet the requirements of Appendix B of 40 CFR part 58. 

(VI) The requirements for pre-construction monitoring 

specified above and under Chapter 6, Section 2(b) with respect to monitoring for a 

particular pollutant may be waived by the Administrator upon petition from an applicant 

if: 

(1.) The emissions increase of the pollutant from a 

new stationary source or the net emissions increase of the pollutant from a modification 

would cause, in any area, air quality impacts less than the following amounts: 

6-23 
a. Carbon Monoxide- 575 J!g/m3

, 8-hour 

average; 

b. Nitrogen Dioxide - 14 J!g/m3

, annual 

average; 

c. 

PM10, 24-hour average; 

•. Sulfur Dioxide - 13 J!g/m3

, 24-hour 

average; 

1. Ozone (No de minimis air quality level is 

provided for ozone; however, any net emissions increase of 100 tons per year or more of 

volatile organic compounds or nitrogen oxides subject to PSD would be required to 

perform an ambient impact analysis, including the gathering of air quality data.) 

average; 

average; 

average; 

1-hour average; or 

1. Lead- 0.1 J!g/m3

, 3-month average; 

•. Fluorides - 0.25 J!g/m3, 24-hour 

1. Total Reduced Sulfur- 10 J!g/m3

, 1-hour 

1. Hydrogen Sulfide - 0.2 J!g/m3

, 1-hour 

1. Reduced Sulfur Compounds- 10 J!g/m3

, 

(2.) The concentrations ofthe pollutant in the area 

that the source or modification would affect are less than the concentrations listed in 

paragraph (b )(i)(E)(VI)( 1.) of this section; or 

(3.) The pollutant is not listed in paragraph 

(b )(i)(E)(VI)( 1.) of this section. 

(F) The Administrator may require an applicant subject to the 

provisions of this section to conduct an approved visibility monitoring program in any 

Class I Area which may be impacted by emissions from the proposed stationary source. 

6-24 
(G) At such time that a particular source or modification becomes 

a major stationary source or major modification solely by virtue of a relaxation in any 

enforceable limitation which was established after August 7, 1980 on the capacity ofthe 

source or modification otherwise to emit a pollutant, then all ofthe provisions of Chapter 

6, Sections 2 and 4 shall apply to the source or modification as though construction had 

not yet commenced on the source or modification. 

(H) The following specific provisions apply to projects at existing 

emissions units at a major stationary source (other than projects at a source with a PAL) 

in circumstances where the owner or operator elects to use the method specified in 

paragraphs (i)(A) through (C) of the definition for "Projected actual emissions" for 

calculating projected actual emissions. 

(I) Before beginning actual construction of the project, the 

owner or operator shall document and maintain a record of the following information: 

(1.) A description ofthe project; 

(2.) Identification ofthe emissions unit(s) whose 

emissions of a regulated NSR pollutant could be affected by the project; and 

(3.) A description of the applicability test used to 

determine that the project is not a major modification for any regulated NSR pollutant, 

including the baseline actual emissions, the projected actual emissions, the amount of 

emissions excluded under paragraph (i)(C) of the definition for "Projected actual 

emissions" in Section 4(a) and an explanation for why such amount was excluded, and 

any netting calculations, if applicable. 

(II) Before beginning actual construction, the owner or 

operator shall provide the information set out in paragraph (b)(i)(H)(I) ofthis section to 

the Division as a Chapter 6, Section 2 permit application. 

(III) The owner or operator shall monitor the emissions of 

any regulated NSR pollutant that could increase as a result of the project and that is 

emitted by any emissions unit identified in paragraph (b)(i)(H)(I)(2.) ofthis section; and 

calculate and maintain a record of the annual emissions, in tons per year on a calendar 

year basis, for a period of 5 years following resumption of regular operations after the 

change, or for a period of 10 years following resumption of regular operations after the 

change if the project increases the design capacity or potential to emit of that regulated 

NSR pollutant at such emissions unit. 

(IV) The owner or operator shall submit a report to the 

Division within 60 days after the end of each year during which records must be 

generated under paragraph (b)(i)(H)(III) of this section setting out the unit's annual 

emissions during the calendar year that preceded submission of the report. 

6-25 
(I) The owner or operator of the source shall make the information 

required to be documented and maintained pursuant to paragraph (b)(i)(H) ofthis section 

available for review upon request for inspection by the Division or the general public 

pursuant to the requirements contained in 40 CFR 70.4(b)(3)(viii). 

(J) (I) Except as otherwise provided in paragraph (b )(xv) of 

this section, and consistent with the definition of "Major modification" contained in 

Section 4(a), a project is a major modification for a regulated NSR pollutant if it causes 

two types of emissions increases - a significant emissions increase (as defined in the 

definition for "Significant emissions increase" in Section 4(a)), and a significant net 

emissions increase (as defined in the definitions for "Net emissions increase" and 

"Significant" in Section 4(a)). The project is not a major modification if it does not cause 

a significant emissions increase. If the project causes a significant emissions increase, 

then the project is a major modification only if it also results in a significant net 

emissions increase. 

(II) The procedure for calculating (before beginning actual 

construction) whether a significant emissions increase (i.e., the first step of the process) 

will occur depends upon the type of emissions units being modified, according to 

paragraphs (b )(i)(J)(III) through (V) of this section. The procedure for calculating 

(before beginning actual construction) whether a significant net emissions increase will 

occur at the major stationary source (i.e., the second step of the process) is contained in 

the definition for "Net emissions increase" in Section 4(a). Regardless of any such 

preconstruction projections, a major modification results if the project causes a 

significant emissions increase and a significant net emissions increase. 

(III) Actual-to-Projected-Actual Applicability Test For 

Projects That Only Involve Existing Emissions Units. A significant emissions increase of 

a regulated NSR pollutant is projected to occur if the sum of the difference between the 

projected actual emissions (as defined in the definition for "Projected actual emissions" 

in Section 4(a)) and the baseline actual emissions (as defined in paragraphs (i) and (ii) in 

the definition of"Baseline actual emissions" in Section 4(a)) for each existing emissions 

unit, equals or exceeds the significant amount for that pollutant (as defined in the 

definition of"Significant" in Section 4(a)). 

(IV) Actual-to-Potential Test For Projects That Only 

Involve Construction of a New Emissions Unit(s). A significant emissions increase of a 

regulated NSR pollutant is projected to occur if the sum of the difference between the 

potential to emit (as defined in the definition for "Potential to emit" in Section 4(a)) from 

each new emissions unit following completion of the project and the baseline actual 

emissions (as defined in paragraph (iii) for the definition of"Baseline actual emissions" 

in Section 4(a)) of these units before the project equals or exceeds the significant amount 

for that pollutant (as defined in the definition of"Significant" in Section 4(a)). 

6-26 
(V) Hybrid Test For Projects That Involve Multiple Types 

of Emissions Units. A significant emissions increase of a regulated NSR pollutant is 

projected to occur if the sum of the emissions increases for each emissions unit, using the 

method specified in paragraphs (b )(i)(J)(III) and (IV) of this section as applicable with 

respect to each emissions unit, for each type of emissions unit equals or exceeds the 

significant amount for that pollutant (as defined in the definition of"Significant" in 

Section 4(a)). 

(ii) (A) The required permit shall not be issued unless the proposed 

major stationary source or major modification would meet an emission limit(s) or 

equipment standard(s) specified by the Administrator to represent the application of Best 

Available Control Technology for each pollutant regulated under these Standards and 

Regulations and under the Federal Clean Air Act and having the potential to emit in 

significant amounts. For phased construction projects, the determination of BACT shall 

be reviewed and modified as appropriate at the latest, most reasonable time no later than 

18 months prior to commencement of each phase of the proposed project. At such time, 

the owner or operator of the applicable stationary source may be required to demonstrate 

the adequacy of any previous determination of best available control technology for the 

stationary source. 

(B) In the case of a major modification, the requirements for Best 

Available Control Technology shall apply only to each new or modified emissions unit at 

which a net emissions increase of the pollutant would occur. 

(C) (I) The applicant for a permit for a source subject to this 

section may petition the Administrator to approve a system of innovative control 

technology. 

(II) The Administrator, with the approval of the 

govemor(s) of other affected state(s) may approve the employment of a system of 

innovative control technology if: 

(I.) The proposed control system would not cause 

or contribute to an unreasonable risk to public health, welfare, or safety in its operation or 

function; 

(2.) The owner or operator agrees to achieve a level 

of continuous emissions reduction equivalent to that which would have been required 

under paragraphs (ii)(A) and (B) above by a date specified by the Administrator. Such 

date shall not be later than 4 years from the time of startup or 7 years from permit 

issuance. 

(3.) The major stationary source or major 

modification would meet the requirements equivalent to those in paragraphs (b)(i)(A)(I), 

(b)(ii)(A), and (b)(ii)(B) above based on the emission rate that the stationary source 

6-27 
employing the system of innovative control technology would be required to meet on the 

date specified by the Administrator. 

(4.) The source or modification would not before 

the date specified by the Administrator: 

a. Cause or contribute to any violation of an 

applicable National Ambient Air Quality Standard, or 

b. Impact any Class I Area, or 

c. Impact any area where an applicable 

increment is known to be violated. 

(5.) All other applicable requirements including 

those for public participation have been met. 

(III) The approval to employ a system of innovative 

control technology shall be withdrawn by the Administrator if: 

( 1.) The proposed system fails by the specified date 

to achieve the required continuous emissions reduction rate, or 

(2.) The proposed system fails before the specified 

date so as to contribute to an unreasonable risk to public health, welfare, or safety, or 

(3.) The Administrator decides at any time that the 

proposed system is unlikely to achieve the required level of control or to protect the 

public health, welfare, or safety. 

(IV) If the source or modification fails to meet the required 

level of continuous emissions reduction within the specified time period or if the 

approval is withdrawn in accordance with (III) above, the Administrator may allow the 

source or modification up to an additional three years to meet the requirement for the 

application of BACT through use of a demonstrated system of control. 

(iii) Temporary particulate matter emissions such as those associated with 

the construction phase of the source shall not be included in the determination on the 

issuance or denial of a required permit and shall not be taken into account when 

determining compliance with the maximum allowable increments in Table 1; however, 

Best Available Control Technology shall be applied to abate such temporary emission. 

(iv) All applications of air quality modeling required under paragraph 

(b )(i) above shall be based on the applicable models, databases, and other requirements 

specified in Appendix W of 40 CFR part 51 (Guideline on Air Quality Models). Where 

6-28 
an air quality model specified in Appendix W of 40 CFR part 51 (Guideline on Air 

Quality Models) is inappropriate, the model may be modified or another model 

substituted. Such a modification or substitution of a model may be made on a case-bycase basis or, where appropriate, on a generic basis for a specific State of Wyoming 

program. Written approval of the EPA Administrator must be obtained for any 

modification or substitution. In addition, use of a modified or substituted model must be 

subject to notice and opportunity for public comment under procedures set forth in 

Chapter 6, Section 2(g). 

(v) In any case where the federal official charged with direct 

responsibility for management of any lands within a Class I Area, or the Administrator of 

EPA or the governor of an adjacent state containing such a Class I Area, files a notice 

alleging that emissions from a proposed source or major modification may cause or 

contribute to a change in the air quality in such area and identifying the potential adverse 

impact of such change, a permit shall not be issued unless the owner or operator of such 

source demonstrates to the satisfaction of the Administrator that emissions of particulate 

matter, sulfur dioxide, and nitrogen oxides will not cause or contribute to concentrations 

which exceed the maximum allowable increases for the Class I Area in question. 

(vi) (A) In any case where a Federal Land Manager demonstrates to 

the satisfaction of the Administrator that the emissions from such source will have an 

adverse impact on the air quality-related values (including visibility) of such Class I 

Areas, notwithstanding the fact that the change in air quality resulting from emissions 

from such source will not cause or contribute to concentrations which exceed the 

maximum allowable increases for Class I Areas, a permit shall not be issued. 

(B) However, in the case where the Federal Land Manager 

provides to the Division at least 30 days prior to the Public Notice issued pursuant to 

Chapter 6, Section 2(m) ofthese regulations, an analysis of the impact ofthe emissions 

on visibility in a Federal Class I Area, the Division must consider such analysis in 

making its proposed decision. If the Federal Land Manager's analysis concludes that an 

adverse impact on visibility in the Federal Class I Area will occur but the Administrator 

determines that the analysis does not demonstrate to his satisfaction that such an adverse 

impact on visibility will occur, the Administrator shall in the Public Notice issued 

pursuant to the requirements of Chapter 6, Section 2(m), explain his decision or give 

notice as to where the explanation can be obtained. 

(vii) In any case where the owner or operator of such source demonstrates 

to the satisfaction of the Federal Land Manager, and the Federal Land Manager so 

certifies, that the emissions from such source will have no adverse impact on the air 

quality-related values of such Class I Areas (including visibility) notwithstanding the fact 

that the change in air quality resulting from emissions from such source will cause or 

contribute to concentrations which exceed the maximum allowable increases for Class I 

Areas, the Administrator may issue a permit. 

6-29 
(viii) In the case of a permit issued pursuant to subsection (vii), such 

source shall comply with such emission limitation under such permit as may be necessary 

to assure that emissions of sulfur oxides, particulate matter, and nitrogen oxides from 

such source, will not cause or contribute to concentrations of such pollutant which 

exceeds the following maximum allowable increases over the baseline concentration for 

such pollutants: 

Particulate matter: 

PM10, annual arithmetic mean 

PM10, 24-hour maximum 

Sulfur dioxide: 

Annual arithmetic mean 

Twenty-four-hour maximum 

Three-hour maximum 

Nitrogen dioxide: 

Annual arithmetic mean 

Maximum Allowable Increase 

(micrograms per cubic meter) 

I 

17 

30 

20 

91 

325 

25 

(ix) (A) In any case where the owner or operator of a proposed major 

stationary source or major modification who has been denied a certification under 

subparagraph (vii) demonstrates to the satisfaction ofthe Governor of Wyoming 

(hereinafter the Governor), after notice and public hearing, and the Governor finds, that 

the source cannot be constructed by reason of any maximum allowable increases for 

sulfur dioxide for periods of twenty-four hours or less applicable to any Class I Area and, 

in the case of federal Mandatory Class I Areas, that a variance under this clause will not 

adversely affect the air quality related values of the area (including visibility), the 

Governor, after consideration of the Federal Land Manager's recommendation (if any) 

and subject to his concurrence, may grant a variance from such maximum allowable 

increase. If a variance is granted, a permit may be issued to such source pursuant to the 

requirements of this subparagraph provided other requirements of this section are met. 

(B) In the case of a permit issued pursuant to subparagraph 

(ix)(A), such source shall comply with such emission limitations under such permit as 

may be necessary to assure that emissions of sulfur oxides from such source will not 

(during any day on which the otherwise applicable maximum allowable increases are 

exceeded) cause or contribute to concentrations which exceed the following maximum 

allowable increases for such areas over the baseline concentration for such pollutant and 

to assure that such emissions will not cause or contribute to concentrations which exceed 

the otherwise applicable maximum allowable increases for periods of exposure of 24 

hours or less on more than 18 days during any annual period. 

6-30 
Period of exposure: 

Low terrain areas: 

24-hr maximum 

3-hr maximum 

High terrain areas: 

24-hr. maximum 

3-hr maximum 

Maximum Allowable Increase 

(micrograms per cubic meter) 

36 

130 

62 

221 

(x) Notwithstanding other requirements of this section, a portable source 

which is a major stationary source and which has otherwise received a construction 

permit under Chapter 6, Sections 2 and 4 shall not be required to obtain additional 

relocation permits under this section if: 

(A) Emissions from the source would not exceed allowable 

emissions; and 

(B) Such relocation would impact no Class I Area and no area 

where an applicable increment is known to be violated; and 

(C) Notice is given to the Division at least 10 days prior to such 

relocation identifying the proposed new location and the probable duration of operation at 

such location; and 

(D) Emissions at the new location will be temporary. 

(xi) After a final decision is made on an application for a source subject to 

this section, the final decision will be transmitted in writing to the applicant and the final 

decision and all comments received by the Division during the public comment period 

will be made available for public inspection in the same location where the application 

and analysis was posted. A copy of each permit application for each source or 

modification subject to this section and impacting a Federal Class I Area will be 

transmitted to EPA. EPA will be provided with notice of each action taken by the 

Division on such application. 

(xii) [Reserved.] 

(xiii) [Reserved.] 

(xiv) [Reserved.] 

(xv) Actuals Plantwide Applicability Limitations (PALs). 

(A) Applicability. 

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(I) The Division may approve the use of an actuals PAL 

for any existing major stationary source if the PAL meets the requirements in paragraphs 

(b)(xv)(A) through (0) of this section. The term "PAL" shall mean "actuals PAL" 

throughout paragraph (b)(xv) of this section. 

(II) Any physical change in or change in the method of 

operation of a major stationary source that maintains its total source-wide emissions 

below the PAL level, meets the requirements in paragraphs (b)(xv)(A) through (0) of this 

section, and complies with the PAL permit: 

( 1.) Is not a major modification for the PAL 

pollutant; 

(2.) Does not have to be approved through a 

Chapter 6, Section 4 permit; and 

(3.) Is not subject to the provisions in paragraph 

(b)(i)(G) of this section (restrictions on relaxing enforceable emission limitations that the 

major stationary source used to avoid applicability of Chapter 6, Section 4). 

(III) Except as provided under paragraph (b)(xv)(A)(II)(3.) 

of this section, a major stationary source shall continue to comply with all applicable 

Federal or State of Wyoming requirements, emission limitations, and work practice 

requirements that were established prior to the effective date of the PAL. 

(B) Definitions. The following definitions shall be used for 

actuals PALs consistent with paragraphs (b)(xv)(A) through (0) of this section. When a 

term is not defined in these paragraphs, it shall have the meaning given in Section 4(a) of 

this section or in the Clean Air Act. 

"Actuals PAL for a major stationary source" means a PAL based 

on the baseline actual emissions (as defined in the definition for "Baseline actual 

emissions" in Section 4(a)) of all emissions units (as defined in the definition for 

"Source" in Section 4(a)) at the source, that emit or have the potential to emit the PAL 

pollutant. 

"Allowable emissions" has the same meaning as in the definition 

for "Allowable emissions" in Section 4(a), except as this definition is modified according 

to paragraphs (i) and (ii) ofthis definition. 

(i) The allowable emissions for any emissions unit shall be 

calculated considering any emission limitations that are enforceable as a practical matter 

on the emissions unit's potential to emit. 

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(ii) An emissions unit's potential to emit shall be 

determined using the definition of"Potential to emit" in Section 4(a), except that the 

words "or enforceable as a practical matter" should be added after "enforceable". 

"Major emissions unit" means: 

(i) Any emissions unit that emits or has the potential to 

emit 100 tons per year or more ofthe PAL pollutant in an attainment area; or 

(ii) Any emissions unit that emits or has the potential to 

emit the PAL pollutant in an amount that is equal to or greater than the major source 

threshold for the PAL pollutant as defined by the Clean Air Act for nonattainment areas. 

(For example, in accordance with the definition of major stationary source in section 

182(c) of the Clean Air Act, an emissions unit would be a major emissions unit for VOC 

if the emissions unit is located in a serious ozone nonattainment area and it emits or has 

the potential to emit 50 or more tons ofVOC per year.) 

"PAL effective date" generally means the date of issuance of the 

PAL permit; however, the PAL effective date for an increased PAL is the date any 

emissions unit that is part of the PAL major modification becomes operational and begins 

to emit the PAL pollutant. 

"PAL effective period" means the period beginning with the PAL 

effective date and ending 10 years later. 

"PAL major modification" means, notwithstanding the definitions 

for "Major modification" and ''Net emissions increase" of Section 4(a), any physical 

change in or change in the method of operation of the PAL source that causes it to emit 

the PAL pollutant at a level equal to or greater than the PAL. 

({PAL permit" means the Chapter 6, Section 2 or Section 4 permit 

issued by the Division that establishes a PAL for a major stationary source. 

"PAL pollutant" means the pollutant for which a PAL is 

established at a major stationary source. 

"Plantwide applicability limitation (PAL)" means an emission 

limitation expressed in tons per year, for a pollutant at a major stationary source, that is 

enforceable as a practical matter and established source-wide in accordance with 

paragraphs (b)(xv)(A) through (0) of this section. 

"Significant emissions unit" means an emissions unit that emits or 

has the potential to emit a PAL pollutant in an amount that is equal to or greater than the 

significant level (as defined in the definition for "Significant" in Section 4(a) or in the 

Clean Air Act, whichever is lower) for that PAL pollutant, but less than the amount that 

6-33 
would qualify the unit as a major emissions unit as defined in paragraph (b)(xv)(B) for 

the definition of "Major emissions unit" of this section. 

"Small emissions unit" means an emissions unit that emits or has 

the potential to emit the PAL pollutant in an amount less than the significant level for that 

PAL pollutant, as defined in the definition for "Significant" in Section 4(a) or in the 

Clean Air Act, whichever is lower. 

(C) Permit Application Requirements. As part of a permit 

application requesting a PAL, the owner or operator of a major stationary source shall 

submit the following information in paragraphs (b)(xv)(C)(I) through (III) of this section 

to the Division for approval. 

(I) A List of All Emissions Units at the Source Designated 

as Small, Significant or Major Based on Their Potential to Emit. In addition, the owner 

or operator ofthe source shall indicate which, if any, Federal or State ofWyoming 

applicable requirements, emission limitations, or work practices apply to each unit. 

(II) Calculations of the Baseline Actual Emissions (With 

Supporting Documentation). Baseline actual emissions are to include emissions 

associated not only with operation of the unit, but also emissions associated with startup, 

shutdown, and malfunction. 

(III) The calculation procedures that the major stationary 

source owner or operator proposes to use to convert the monitoring system data to 

monthly emissions and annual emissions based on a 12-month rolling total for each 

month as required by paragraph (b)(xv)(M)(I) of this section. 

(D) General Requirements For Establishing PALs. 

(I) The Division may establish a PAL at a major stationary 

source, provided that at a minimum, the requirements in paragraphs (b)(xv)(D)(I)(l.) 

through (7.) of this section are met. 

(1.) The PAL shall impose an annual emission 

limitation in tons per year, that is enforceable as a practical matter, for the entire major 

stationary source. For each month during the PAL effective period after the first 12 

months of establishing a PAL, the major stationary source owner or operator shall show 

that the sum of the monthly emissions from each emissions unit under the PAL for the 

previous 12 consecutive months is less than the PAL (a 12-month average, rolled 

monthly). For each month during the first 11 months from the PAL effective date, the 

major stationary source owner or operator shall show that the sum of the preceding 

monthly emissions from the PAL effective date for each emissions unit under the PAL is 

less than the PAL. 

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(2.) The PAL shall be established in a PAL permit 

that meets the public participation requirements in paragraph (b)(xv)(E) of this section. 

(3.) The PAL permit shall contain all the 

requirements of paragraph (b)(xv)(G) ofthis section. 

(4.) The PAL shall include fugitive emissions, to 

the extent quantifiable, from all emissions units that emit or have the potential to emit the 

PAL pollutant at the major stationary source. 

(5.) Each PAL shall regulate emissions of only one 

pollutant. 

(6.) Each PAL shall have a PAL effective period of 

10 years. 

(7.) The owner or operator of the major stationary 

source with a PAL shall comply with the monitoring, recordkeeping, and reporting 

requirements provided in paragraphs (b)(xv)(L) through (N) of this section for each 

emissions unit under the PAL through the PAL effective period. 

(II) At no time (during or after the PAL effective period) 

are emissions reductions of a PAL pollutant that occur during the PAL effective period 

creditable as decreases for purposes of offsets under 40 CFR part 51.165( a)(3)(ii) unless 

the level of the PAL is reduced by the amount of such emissions reductions and such 

reductions would be creditable in the absence ofthe PAL. 

(E) Public Participation Requirements For PALs. PALs for 

existing major stationary sources shall be established, renewed, or increased, through a 

procedure that is consistent with Chapter 6, Section 2. This includes the requirement that 

the Division provide the public with notice of the proposed approval of a PAL permit and 

at least a 30-day period for submittal of public comment. The Division must address all 

material comments before taking final action on the permit. 

(F) Setting the 10-Year Actuals PAL Level. 

(I) Except as provided in paragraph (b)(xv)(F)(II) ofthis 

section, the actuals PAL level for a major stationary source shall be established as the 

sum of the baseline actual emissions (as defined in the definition for "Baseline actual 

emissions" in Section 4(a)) of the PAL pollutant for each emissions unit at the source; 

plus an amount equal to the applicable significant level for the PAL pollutant under the 

definition of"Significant" in Section 4(a) or under the Clean Air Act, whichever is lower. 

When establishing the actuals PAL level, for a PAL pollutant, only one consecutive 24-

month period must be used to determine the baseline actual emissions for all existing 

emissions units; however, a different consecutive 24-month period may be used for each 

6-35 
different PAL pollutant. Emissions associated with units that were permanently shut 

down after this 24-month period must be subtracted from the PAL level. The Division 

shall specify a reduced PAL level(s) (in tons/yr) in the PAL permit to become effective 

on the future compliance date(s) of any applicable Federal or State of Wyoming 

regulatory requirement( s) that the Division is aware of prior to issuance of the PAL 

permit. For instance, if the source owner or operator will be required to reduce emissions 

from industrial boilers in half from baseline emissions of 60 ppm NOx to a new rule limit 

of 30 ppm, then the permit shall contain a future effective PAL level that is equal to the 

current PAL level reduced by half of the original baseline emissions of such unit(s). 

(II) For newly constructed units (which do not include 

modifications to existing units) on which actual construction began after the 24-month 

period, in lieu of adding the baseline actual emissions as specified in paragraph 

(b)(xv)(F)(I) ofthis section, the emissions must be added to the PAL level in an amount 

equal to the potential to emit of the units. 

(G) Contents ofthe PAL Permit. The PAL permit shall contain, at 

a minimum, the information in paragraphs (b)(xv)(G)(I) through (X) of this section. 

(I) The PAL pollutant and the applicable source-wide 

emission limitation in tons per year. 

(II) The PAL permit effective date and the expiration date 

ofthe PAL (PAL effective period). 

(III) Specification in the PAL permit that if a major 

stationary source owner or operator applies to renew a PAL in accordance with paragraph 

(b)(xv)(J) of this section before the end of the PAL effective period, then the PAL shall 

not expire at the end of the PAL effective period. It shall remain in effect until a revised 

PAL permit is issued by the Division. 

(IV) A requirement that emission calculations for 

compliance purposes include emissions from startups, shutdowns and malfunctions. 

(V) A requirement that, once the PAL expires, the major 

stationary source is subject to the requirements of paragraph (b)(xv)(I) of this section. 

(VI) The calculation procedures that the major stationary 

source owner or operator shall use to convert the monitoring system data to monthly 

emissions and annual emissions based on a 12-month rolling total for each month as 

required by paragraph (b)(xv)(C)(I) of this section. 

(VII) A requirement that the major stationary source owner 

or operator monitor all emissions units in accordance with the provisions under paragraph 

(b)(xv)(M) of this section. 

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(VIII) A requirement to retain the records required under 

paragraph (b)(xv)(M) of this section on site. Such records may be retained in an 

electronic format. 

(IX) A requirement to submit the reports required under 

paragraph (b)(xv)(N) of this section by the required deadlines. 

(X) Any other requirements that the Division deems 

necessary to implement and enforce the PAL. 

(H) PAL Effective Period and Reopening of the PAL Permit. 

(I) PAL Effective Period. The PAL effective period shall 

be 10 years. 

(II) Reopening of the PAL Permit. 

(1.) During the PAL effective period, the Division 

shall reopen the PAL permit to: 

a. Correct typographical/calculation errors 

made in setting the PAL or reflect a more accurate determination of emissions used to 

establish the PAL; 

b. Reduce the PAL if the owner or operator 

of the major stationary source creates creditable emissions reductions for use as offsets 

under 40 CFR part 51.165(a)(3)(ii); and 

c. Revise the PAL to reflect an increase in 

the PAL as provided under paragraph (b)(xv)(K) of this section. 

(2.) The Division may reopen the PAL permit for 

the following: 

a. Reduce the PAL to reflect newly 

applicable Federal requirements (for example, NSPS) with compliance dates after the 

PAL effective date; 

b. Reduce the PAL consistent with any 

other requirement, that is enforceable as a practical matter, and that the Division may 

impose on the major stationary source; and 

c. Reduce the PAL if the Division 

determines that a reduction is necessary to avoid causing or contributing to a NAAQS or 

6-37 
PSD increment violation, or to an adverse impact on an AQRV that has been identified 

for a Federal Class I Area by a Federal Land Manager and for which information is 

available to the general public. 

(3.) Except for the permit reopening in paragraph 

(b )(xv )(H)(II)( 1. )a. of this section for the correction of typographicaVcalculation errors 

that do not increase the PAL level, all reopenings shall be carried out in accordance with 

the public participation requirements of paragraph (b)(xv)(E) of this section. 

(I) Expiration of a PAL. Any PAL that is not renewed in 

accordance with the procedures in paragraph (b)(xv)(J) of this section shall expire at the 

end of the PAL effective period, and the requirements in paragraphs (b)(xv)(I)(I) through 

(V) ofthis section shall apply. 

(I) Each emissions unit (or each group of emissions units) 

that existed under the PAL shall comply with an allowable emission limitation under a 

revised permit established according to the procedures in paragraphs (b)(xv)(I)(I)(l.) and 

(2.) ofthis section. 

(1.) Within the time frame specified for PAL 

renewals in paragraph (b)(xv)(J)(II) of this section, the major stationary source shall 

submit a proposed allowable emission limitation for each emissions unit (or each group 

of emissions units, if such a distribution is more appropriate as decided by the Division) 

by distributing the PAL-allowable emissions for the major stationary source among each 

of the emissions units that existed under the PAL. lfthe PAL had not yet been adjusted 

for an applicable requirement that became effective during the PAL effective period, as 

required under paragraph (b)(xv)(J)(V) of this section, such distribution shall be made as 

ifthe PAL had been adjusted. 

(2.) The Division shall decide whether and how the 

PAL-allowable emissions will be distributed and issue a revised permit incorporating 

allowable limits for each emissions unit, or each group of emissions units, as the Division 

determines is appropriate. 

(II) Each emissions unit(s) shall comply with the allowable 

emission limitation on a 12-month rolling basis. The Division may approve the use of 

monitoring systems (source testing, emission factors, etc.) other than CEMS, CERMS, 

PEMS or CPMS to demonstrate compliance with the allowable emission limitation. 

(Ill) Until the Division issues the revised permit 

incorporating allowable limits for each emissions unit, or each group of emissions units, 

as required under paragraph (b)(xv)(I)(I)(2.) of this section, the source shall continue to 

comply with a source-wide, multi-unit emissions cap equivalent to the level of the PAL 

emission limitation. 

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(IV) Any physical change or change in the method of 

operation at the major stationary source will be subject to Chapter 6, Section 4 

requirements if such change meets the definition of"Major modification" in Section 4(a). 

(V) The major stationary source owner or operator shall 

continue to comply with any State of Wyoming or Federal applicable requirements 

(BACT, RACT, NSPS, etc.) that may have applied either during the PAL effective period 

or prior to the PAL effective period except for those emission limitations that had been 

established pursuant to paragraph (b)(i)(G) of this section, but were eliminated by the 

PAL in accordance with the provisions in paragraph (b)(xv)(A)(II)(3.) of this section. 

(J) Renewal of a PAL. 

(I) The Division shall follow the procedures specified in 

paragraph (b)(xv)(E) of this section in approving any request to renew a PAL for a major 

stationary source, and shall provide both the proposed PAL level and a written rationale 

for the proposed PAL level to the public for review and comment. During such public 

review, any person may propose a PAL level for the source for consideration by the 

Division. 

(II) Application Deadline. A major stationary source 

owner or operator shall submit a timely application to the Division to request renewal of 

a PAL. A timely application is one that is submitted at least 6 months prior to, but not 

earlier than 18 months from, the date of permit expiration. This deadline for application 

submittal is to ensure that the permit will not expire before the permit is renewed. If the 

owner or operator of a major stationary source submits a complete application to renew 

the PAL within this time period, then the PAL shall continue to be effective until the 

revised permit with the renewed PAL is issued. 

(Ill) Application Requirements. The application to renew 

a PAL permit shall contain the information required in paragraphs (b)(xv)(J)(III)(l.) 

through (4.) of this section. 

(1.) The information required in paragraphs 

(b)(xv)(C)(I) through (III) of this section. 

(2.) A proposed PAL level. 

(3.) The sum of the potential to emit of all 

emissions units under the PAL (with supporting documentation). 

(4.) Any other information the owner or operator 

wishes the Division to consider in determining the appropriate level for renewing the 

PAL. 

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(IV) PAL Adjustment. In determining whether and how to 

adjust the PAL, the Division shall consider the options outlined in paragraphs 

(b)(xv)(J)(IV)(l.) and (2.) of this section; however, in no case may any such adjustment 

fail to comply with paragraph (b)(xv)(J)(IV)(3.) of this section. 

( 1.) If the emissions level calculated in accordance 

with paragraph (b)(xv)(F) of this section is equal to or greater than 80 percent of the PAL 

level, the Division may renew the PAL at the same level without considering the factors 

set forth in paragraph (b)(xv)(J)(IV)(2.) of this section; or 

(2.) The Division may set the PAL at a level that it 

determines to be more representative of the source's baseline actual emissions, or that it 

determines to be appropriate considering air quality needs, advances in control 

technology, anticipated economic growth in the area, desire to reward or encourage the 

source's voluntary emissions reductions, or other factors as specifically identified by the 

Division in its written rationale. 

(3.) Notwithstanding paragraphs (b)(xv)(J)(IV)(1.) 

and (2.) of this section: 

a. If the potential to emit of the major 

stationary source is less than the PAL, the Division shall adjust the PAL to a level no 

greater than the potential to emit of the source; and 

b. The Division shall not approve a renewed 

PAL level higher than the current PAL, unless the major stationary source has complied 

with the provisions of paragraph (b)(xv)(K) of this section (increasing a PAL). 

(V) If the compliance date for a State of Wyoming or 

Federal requirement that applies to the PAL source occurs during the PAL effective 

period, and if the Division has not already adjusted for such requirement, the PAL shall 

be adjusted at the time of PAL permit renewal or Chapter 6, Section 3 operating permit 

renewal, whichever occurs first. 

(K) Increasing a PAL During the PAL Effective Period. 

(I) The Division may increase a PAL emission limitation 

only if the major stationary source complies with the provisions in paragraphs 

(b)(xv)(K)(I)(l.) through (4.) ofthis section. 

( 1.) The owner or operator of the major stationary 

source shall submit a complete application to request an increase in the PAL limit for a 

PAL major modification. Such application shall identify the emissions unit(s) 

contributing to the increase in emissions so as to cause the major stationary source's 

emissions to equal or exceed its PAL. 

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(2.) As part of this application, the major stationary 

source owner or operator shall demonstrate that the sum of the baseline actual emissions 

ofthe small emissions units, plus the sum ofthe baseline actual emissions of the 

significant and major emissions units assuming application of BACT equivalent controls, 

plus the sum of the allowable emissions of the new or modified emissions unit(s), 

exceeds the PAL. The level of control that would result from BACT equivalent controls 

on each significant or major emissions unit shall be determined by conducting a new 

BACT analysis at the time the application is submitted, unless the emissions unit is 

currently required to comply with a BACT or LAER requirement that was established 

within the preceding I 0 years. In such a case, the assumed control level for that 

emissions unit shall be equal to the level of BACT or LAER with which that emissions 

unit must currently comply. 

(3.) The owner or operator obtains a Chapter 6, 

Section 4 permit for all emissions unit(s) identified in paragraph (b)(xv)(K)(I)(l.) of this 

section, regardless of the magnitude ofthe emissions increase resulting from them (that 

is, no significant levels apply). These emissions unit(s) shall comply with any emissions 

requirements resulting from the Chapter 6, Section 4 process (for example, BACT), even 

though they have also become subject to the PAL or continue to be subject to the PAL. 

(4.) The PAL permit shall require that the increased 

PAL level shall be effective on the day any emissions unit that is part ofthe PAL major 

modification becomes operational and begins to emit the PAL pollutant. 

(II) The Division shall calculate the new PAL as the sum 

of the allowable emissions for each modified or new emissions unit, plus the sum of the 

baseline actual emissions of the significant and major emissions units (assuming 

application of BACT equivalent controls as determined in accordance with paragraph 

(b)(xv)(K)(I)(2.) ofthis section), plus the sum ofthe baseline actual emissions of the 

small emissions units. 

(III) The PAL permit shall be revised to reflect the 

increased PAL level pursuant to the public notice requirements of paragraph (b)(xv)(E) of 

this section. 

(L) Monitoring Requirements for PALs. 

(I) General Requirements. 

(1.) Each PAL permit must contain enforceable 

requirements for the monitoring system that accurately determines plantwide emissions 

ofthe PAL pollutant in terms of mass per unit of time. Any monitoring system 

authorized for use in the PAL permit must be based on sound science and meet generally 

acceptable scientific procedures for data quality and manipulation. Additionally, the 

6-41 
information,generated by such system must meet minimum legal requirements for 

admissibility in a judicial proceeding to enforce the PAL permit. 

(2.) The PAL monitoring system must employ one 

or more of the four general monitoring approaches meeting the minimum requirements 

set forth in paragraphs (b)(xv)(L)(II)(l.) through (4.) of this section and must be 

approved by the Division. 

(3.) Notwithstanding paragraph (b)(xv)(L)(I)(2.) of 

this section, you may also employ an alternative monitoring approach that meets 

paragraph (b )(xv)(L )(1)(1.) of this section if approved by the Division. 

(4.) Failure to use a monitoring system that meets 

the requirements of this section renders the PAL invalid. 

(II) Minimum Performance Requirements For Approved 

Monitoring Approaches. The following are acceptable general monitoring approaches 

when conducted in accordance with the minimum requirements in paragraphs 

(b)(xv)(L)(III) through (IX) of this section: 

( 1.) Mass balance calculations for activities using 

coatings or solvents; 

(2.) CEMS; 

(3.) CPMS or PEMS; and 

(4.) Emission factors. 

(III) Mass Balance Calculations. An owner or operator 

using mass balance calculations to monitor PAL pollutant emissions from activities using 

coating or solvents shall meet the following requirements: 

(1.) Provide a demonstrated means of validating the 

published content of the PAL pollutant that is contained in or created by all materials 

used in or at the emissions unit; 

(2.) Assume that the emissions unit emits all of the 

PAL pollutant that is contained in or created by any raw material or fuel used in or at the 

emissions unit, if it cannot otherwise be accounted for in the process; and 

(3.) Where the vendor of a material or fuel, which 

is used in or at the emissions unit, publishes a range of pollutant content from such 

material, the owner or operator must use the highest value of the range to calculate the 

6-42 
PAL pollutant emissions unless the Division determines there is site-specific data or a 

site-specific monitoring program to support another content within the range. 

(IV) CEMS. An owner or operator using CEMS to 

monitor PAL pollutant emissions shall meet the following requirements: 

(1.) CEMS must comply with applicable 

Performance Specifications found in 40 CFR part 60, Appendix B; and 

(2.) CEMS must sample, analyze, and record data 

at least every 15 minutes while the emissions unit is operating. 

(V) CPMS or PEMS. An owner or operator using CPMS 

or PEMS to monitor PAL pollutant emissions shall meet the following requirements: 

( 1.) The CPMS or the PEMS must be based on 

current site-specific data demonstrating a correlation between the monitored parameter(s) 

and the PAL pollutant emissions across the range of operation of the emissions unit; and 

(2.) Each CPMS or PEMS must sample, analyze, 

and record data at least every 15 minutes, or at another less frequent interval approved by 

the Division, while the emissions unit is operating. 

(VI) Emission Factors. An owner or operator using 

emission factors to monitor PAL pollutant emissions shall meet the following 

requirements: 

(1.) All emission factors shall be adjusted, if 

appropriate, to account for the degree of uncertainty or limitations in the factors' 

development; 

(2.) The emissions unit shall operate within the 

designated range of use for the emission factor, if applicable; and 

(3.) If technically practicable, the owner or operator 

of a significant emissions unit that relies on an emission factor to calculate PAL pollutant 

emissions shall conduct validation testing to determine a site-specific emission factor 

within 6 months of PAL permit issuance, unless the Division determines that testing is 

not required. 

(VII) A source owner or operator must record and report 

maximum potential emissions without considering enforceable emission limitations or 

operational restrictions for an emissions unit during any period of time that there is no 

monitoring data, unless another method for determining emissions during such periods is 

specified in the PAL permit. 

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(VIII) Notwithstanding the requirements in paragraphs 

(b)(xv)(L)(III) through (VIII) of this section, where an owner or operator of an emissions 

unit cannot demonstrate a correlation between the monitored parameter(s) and the PAL 

pollutant emissions rate at all operating points of the emissions unit, the Division shall, at 

the time of permit issuance: 

(l.) Establish default value(s) for determining 

compliance with the PAL based on the highest potential emissions reasonably estimated 

at such operating point(s); or 

(2.) Determine that operation of the emissions unit 

during operating conditions when there is no correlation between monitored parameter(s) 

and the PAL pollutant emissions is a violation of the PAL. 

(IX) Re-validation. All data used to establish the PAL 

pollutant must be re-validated through performance testing or other scientifically valid 

means approved by the Division. Such testing must occur at least once every 5 years after 

issuance of the PAL. 

(M) Recordkeeping Requirements. 

(I) The PAL permit shall require an owner or operator to 

retain a copy of all records necessary to determine compliance with any requirement of 

paragraph (b)(xv) of this section and of the PAL, including a determination of each 

emissions unit's 12-month rolling total emissions, for 5 years from the date of such 

record. 

(II) The PAL permit shall require an owner or operator to 

retain a copy of the following records, for the duration of the PAL effective period plus 5 

years: 

(l.) A copy of the PAL permit application and any 

applications for revisions to the PAL; and 

(2.) Each annual certification of compliance 

pursuant to Chapter 6, Section 3 and the data relied on in certifying the compliance. 

(N) Reporting and Notification Requirements. The owner or 

operator shall submit semi-annual monitoring reports and prompt deviation reports to the 

Division in accordance with the applicable Chapter 6, Section 3 operating permit 

program. The reports shall meet the requirements in paragraphs (b)(xv)(N)(I) through 

(III) of this section. 

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(I) Semi-annual Report. The semi-annual report shall be 

submitted to the Division within 30 days of the end of each reporting period. This report 

shall contain the information required in paragraphs (b)(xv)(N)(I)(l.) through (7.) of this 

section. 

( 1.) The identification of owner and operator and 

the permit number. 

(2.) Total annual emissions (tons/year) based on a 

12-month rolling total for each month in the reporting period recorded pursuant to 

paragraph (b)(xv)(M)(I) of this section. 

(3.) All data relied upon, including, but not limited 

to, any Quality Assurance or Quality Control data, in calculating the monthly and annual 

PAL pollutant emissions. 

( 4.) A list of any emissions units modified or added 

to the major stationary source during the preceding 6-month period. 

(5.) The number, duration, and cause of any 

deviations or monitoring malfunctions (other than the time associated with zero and span 

calibration checks), and any corrective action taken. 

(6.) A notification of a shutdown of any monitoring 

system, whether the shutdown was permanent or temporary, the reason for the shutdown, 

the anticipated date that the monitoring system will be fully operational or replaced with 

another monitoring system, and whether the emissions unit monitored by the monitoring 

system continued to operate, and the calculation of the emissions of the pollutant or the 

number determined by method included in the permit, as provided by paragraph 

(b)(xv)(L)(VII) ofthis section. 

(7.) A signed statement by the responsible official 

(as defined by the applicable Chapter 6, Section 3 operating permit program) certifying 

the truth, accuracy, and completeness of the information provided in the report. 

(II) Deviation Report. The major stationary source owner 

or operator shall promptly submit reports of any deviations or exceedance of the PAL 

requirements, including periods where no monitoring is available. A report submitted 

pursuant to Chapter 6, Section 3(h)(i)(C)(III)(2.) shall satisfy this reporting requirement. 

The deviation reports shall be submitted within the time limits prescribed by Chapter 6, 

Section 3(h)(i)(C)(III)(2.). The reports shall contain the following information: 

( 1.) The identification of owner and operator and 

the permit number; 

6-45 
(2.) The PAL requirement that experienced the 

deviation or that was exceeded; 

(3.) Emissions resulting from the deviation or the 

exceedance;and 

(4.) A signed statement by the responsible official 

(as defined by the applicable Chapter 6, Section 3 operating permit program) certifying 

the truth, accuracy, and completeness of the information provided in the report. 

(III) Re-validation Results. The owner or operator shall 

submit to the Division the results of any re-validation test or method within three months 

after completion of such test or method. 

(0) Transition Requirements. 

(I) The Division shall not issue a PAL that does not 

comply with the requirements in paragraphs (b)(xv)(A) through (0) ofthis section after 

the Administrator has approved regulations incorporating these requirements into Chapter 

6, Section 4. 

(II) The Division may supersede any PAL which was 

established prior to the date of approval of this regulation by the Administrator of EPA 

with a PAL that complies with the requirements of paragraphs (b)(xv)(A) through (0) of 

this section. 

(xvi) If any provision of this section, or the application of such provision 

to any person or circumstance, is held invalid, the remainder ofthis section, or the 

application of such provision to persons or circumstances other than those as to which it 

is held invalid, shall not be affected thereby. 

(xvii) Transition: 

(A) The requirements for BACT in Chapter 6, Section 4(b)(ii) and 

the requirements for air quality analysis in Chapter 6, Section 4(b )(i) shall not apply to a 

major stationary source or major modification that was subject to Chapter 6, Section 4, as 

effective on January 25, 1979, if the owner or operator of the source submitted an 

application for a permit under these regulations before August 7, 1980, and the 

Administrator subsequently determines that the application submitted before that date 

was complete. Instead, the requirements of Chapter 6, Section 4 as in effect on January 

25, 1979, apply to any such source or modification. 

(B) The requirements for air quality monitoring in paragraph 

(b )(i)(E) shall not apply to a particular source or modification that was subject to Chapter 

6, Section 4, as effective on January 25, 1979, ifthe owner or operator ofthe source or 

6-46 
modification submits an application for a permit under these regulations on or before 

June 8, 1981, and the Administrator subsequently determines that the application 

submitted before that date was complete with respect to the requirements for ambient air 

quality data analyses as in effect on January 25, 1979. Instead, the latter requirements 

shall apply to such source or modification. 

(C) The requirements for air quality monitoring in paragraph 

(b )(i)(E) shall not apply to a particular source or modification that was not subject to 

Chapter 6, Section 4, as effective on January 25, 1979, ifthe owner or operator of the 

source or modification submits an application for a permit under these regulations before 

June 8, 1981, and the Administrator subsequently determines that the application as 

submitted before that date was complete except with respect to the requirements in 

paragraph (b )(i)(F). 

(D) The requirements for air quality monitoring for PM10 in 

paragraphs (b)(i)(E)(I) through (IV) of this section, effective February 13, 1989, shall not 

apply to a particular source or modification, if the owner or operator of the source or 

modification submits an application for a permit under Chapter 6, Section 4 on or before 

June 1, 1988 and the Administrator subsequently determines that the application 

submitted before that date was complete, except with respect to the requirements for 

monitoring particulate matter. 

(E) The requirements for air quality monitoring ofPM10 in 

paragraphs (b )(i)(E)(IV) through (b )(i)(E)(V) of this section, effective February 13, 1989, 

shall apply to a particular source or modification if the owner or operator of the source or 

modification submits an application for a permit under this section after June 1, 1988 and 

no later than December 1, 1988. The data shall have been gathered over at least the 

period from February 1, 1988 to the date the application becomes otherwise complete in 

accordance with the provisions set forth under paragraph (b)(xvii)(G) of this section, 

except that the Administrator may provide that the monitoring period specification may 

be reduced to a minimum of four months ifhe is satisfied that a complete and adequate 

analysis can be accomplished with monitoring data gathered over that shorter period of 

time. 

(F) For any application under this section that becomes complete 

except as to the requirements of paragraphs (b )(i)(E)(III) and (b )(i)(E)(IV) pertaining to 

PM10, after December 1, 1988 and no later than August 1, 1989, the data that paragraph 

(b )(i)(E)(III) requires will have been gathered over at least the period from August 1 , 

1988 to the date the application becomes otherwise complete. The Administrator may 

provide that the monitoring period specification may be reduced to a minimum of four 

months if he is satisfied that a complete and adequate analysis can be accomplished with 

monitoring data gathered over that shorter period of time. 

(G) With respect to any requirements for air quality monitoring of 

PM10 specified under paragraphs (b)(xvii)(D) and (b)(xvii)(E) ofthis section, effective 

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February 13, 1989, the owner or operator of the source or modification shall use a 

monitoring method approved by the Administrator and shall estimate the ambient 

concentrations of PM10 using the data collected by such approved monitoring method in 

accordance with estimating procedures approved by the Administrator. 

(H) The requirement to demonstrate compliance with the 

maximum allowable increment for nitrogen dioxide shall not apply to a major stationary 

source or major modification that was subject to Chapter 6, Section 4, as effective on 

February 8, 1988, if the owner or operator of the source or modification submits an 

application for a permit under these regulations on or before October 30, 1990 and the 

Administrator subsequently determines that the application submitted before that date 

was complete. 

(I) The requirement to demonstrate compliance with the maximum 

allowable increment for PM10 shall not apply to a major stationary source or major 

modification that was subject to Chapter 6, Section 4, as effective on June 3, 1993, if the 

owner or operator of the source or modification submits an application for a permit under 

these regulations on or before the effective date of this regulation revision and the 

Administrator subsequently determines that the application submitted before that date 

was complete. Instead, the requirement to demonstrate compliance with the maximum 

allowable increment for TSP, as in effect at the time the application was submitted, shall 

apply: 

Maximum Allowable Increments of Deterioration - J.lg/m3 

Pollutant Class I Class II 

Particulate Matter: 

TSP, Annual geometric mean 

TSP, 24-hour maximum* 

5 

10 

19 

37 

*Maximum allowable increment may be exceeded once per year at any receptor site. 

(c) All national parks, national wilderness areas, and national memorial parks in 

Wyoming as of January 25, 1979, shall be designated Class I and may not be 

redesignated. All other areas of the State of Wyoming shall be designated Class II as of 

the effective date of this regulation. 

(d) Redesignation. All redesignation of areas within the State of Wyoming shall 

be accomplished through the process of establishment of Standards and Regulations set 

forth in the Wyoming Environmental Quality Act. 

(i) The following areas may be redesignated only as Class I or Class II 

areas: 

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(A) An area which exceeds 10,000 acres in size and is a national 

monument, a national primitive area, a national preserve, a national recreational area, a 

national wild and scenic river, a national wildlife refuge, a national lakeshore; and 

(B) A national park or national wilderness area which exceeds 

10,000 acres in size and is established after the effective date of this regulation. 

(ii) Except as provided in paragraph (c) above, any area may be 

redesignated as Class I or II, with the approval of the Administrator of the Environmental 

Protection Agency, in accordance with the provisions of paragraph (iii) below; provided, 

however, that lands within the exterior boundaries of reservations of federally recognized 

Indian tribes may be redesignated to any class, but only by the appropriate Indian 

governing body. 

(iii) (A) At least one public hearing must be held in accordance with 

the provisions for adoption of regulations as set forth in the Administrative Procedures 

Act and the Wyoming Environmental Quality Act. 

(B) At least 30 days prior to the public hearing, a description and 

analysis of the health, environmental, economic, social and energy effects ofthe 

proposed redesignation shall be prepared and made available for public inspection. Any 

person petitioning the Department or Council to redesignate an area shall be responsible 

for preparing or submitting such description and analysis. Such persons shall also be 

responsible for revising this required documentation to the extent necessary to satisfy the 

Administrator of the U.S. EPA. The notice of the public hearing shall contain 

appropriate notification of the availability of the description and analysis of the proposed 

redesignation. 

(C) Agencies from neighboring states, Indian governing bodies, 

Federal Land Managers, and local governments whose land may be affected by the 

proposed redesignation shall be notified at least 30 days prior to the hearing. 

(D) Prior to proposing a redesignation, the Division and the Air 

Quality Advisory Board shall consult with the elected leadership of local and other 

substate general purpose governments in the area covered by the redesignation. 

(E) Prior to public notice of the proposed redesignation the 

Division shall provide written notice to any Federal Land Manager who may be 

responsible for any federal lands within the area proposed for such redesignation and 

shall afford adequate opportunity (but not in excess of 60 days) to confer with the State 

respecting the intended notice of designation. The Federal Land Manager shall be 

offered the opportunity to submit written comments and recommendations with respect to 

such intended notice of redesignation. In redesignating any area with respect to which 

the federal land manager has submitted written comments and recommendations, the 

Division will publish a list of any inconsistency between such redesignation and such 

6-49 

l f 

I !. 
recommendation with an explanation of such inconsistency (together with the reasons for 

making such redesignation against the recommendation of the Federal Land Manager). 

(F) The Council shall review and examine the description and 

analysis prepared pursuant to subparagraph (iii)(B) above prior to any redesignation. 

(iv) (A) If an area has been proposed for redesignation to a more 

stringent class, no permit to construct may be granted to a source which may cause an 

impact in the area proposed for redesignation and for which an application to construct is 

received by the Division after the filing of the petition for redesignation with the 

Environmental Quality Council until the proposed redesignation has been acted upon; 

however, approval may be granted if, in the Administrator's judgment, the proposed 

source would not violate the applicable increments of the proposed redesignation. Such 

approval shall be withheld only so long as in the Administrator's judgment, the petitioner 

is expeditiously proceeding toward development of the "description and analysis" 

required under (iii)(B) above, and provided that such "description and analysis" is 

complete and submitted to the Council for action on the petition within 18 months of the 

filing of the initial petition. Upon good cause shown, the Council may extend the 

foregoing deadline. 

(B) Where an application for a permit to construct a source has 

been received by the Division prior to the receipt by the Council of a petition for 

redesignation of an area to a more stringent class and where such source may cause an 

impact in the area proposed for redesignation, the permit application shall be processed 

considering the classification of an area which existed at the time of permit application. 

For purposes of establishing a priority date under this Chapter 6, Section 4( d)(vi)(B), (1) 

such permit application is not required to meet the provisions for completeness in 

Chapter 6, Section 2, and (2) the time frames in Chapter 6, Section 2(g) for action on 

applications shall not apply. 

However, a priority date established under Chapter 6, Section 4(d)(vi)(B), shall remain in 

effect only so long as in the Administrator's judgment, the applicant is expeditiously 

proceeding toward the development and submittal of such other information and data as 

required to make the application complete under the provisions of Chapter 6, Section 2, 

and provided that such other information and data is submitted to, and judged to be 

complete by the Administrator within 18 months of the filing of the initial permit 

application. Upon good cause shown, the Administrator may extend the foregoing 

deadline. 

Section J 3. Nonattainment permit requirements. 

(a) 40 CFR part 51.165 is herein iucomorated by refereuce. jn its entiretv. with 

the exception of paragraph <al and paragraph (al( 1 ). 

6-50 
Section 14. lncorooratjon by reference. 

:~= ~ liiit:n!iincf:Jlin~u:1:e!~:a~!i::::ised and 

incomorated by refereuce. Copies ofthe Code of Federal Regulations are available for 

public inspection and copies can be obtained at cost from ~ Dc;partmept of 

Enviroomental Qualitv. Division of Air Oualitv. 122 W. 2S Street. Cheyenne. Wvoming 

82002. Conies oftbe CFRs can also be obtained at cost from Government Institutes. 

15200 NBN Wav. Building B, Blue Ridge Summit, PA 17214. 

6-51