Including Revised Chapter 173-

400 WAC in the Washington 

State Implementation Plan

Rule SIP Revision

December 2013

Publication no. 13-02-029
ii

Publication and Contact Information

The document is available on the Department of Ecology’s website at 

https://fortress.wa.gov/ecy/publications/SummaryPages/1302039.html

For more information contact:

Anya Caudill

Air Quality

P.O. Box 47600 

Olympia, WA 98504-7600 

Phone: 360-407-6630

Washington State Department of Ecology - www.ecy.wa.gov

o Headquarters, Olympia 360-407-6000

o Northwest Regional Office, Bellevue 425-649-7000

o Southwest Regional Office, Olympia 360-407-6300

o Central Regional Office, Yakima 509-575-2490

o Eastern Regional Office, Spokane 509-329-3400

If you need this document in a format for the visually impaired, call the Air Quality at 360-407-

6600. Persons with hearing loss can call 711 for Washington Relay Service. Persons with a 

speech disability can call 877-833-6341.
iii

Including Revised Chapter 173-400 

WAC in the Washington State 

Implementation Plan

Rule SIP Revision

By

Department of Ecology

Air Quality

Washington State Department of Ecology

Olympia, Washington
iv

Table of Contents

I. Introduction ............................................................................................................................. 1

Differences Between the Proposed SIP Revision and Final SIP Revision ................................. 1

Document Organization .............................................................................................................. 2

II. Background ............................................................................................................................. 3

Statutory Authority...................................................................................................................... 7

Prevention of Significant Deterioration Program Description.................................................... 8

III. Proposed Revisions to the SIP-Approved Chapter 173-400 WAC....................................... 10

Organization.............................................................................................................................. 10

SIP Revisions Discussion.......................................................................................................... 11

1. Section 173-400-020 WAC, “Applicability.” ................................................................ 11

2. Section 173-400-030 WAC, “Definitions.” ................................................................... 11

3. Section 173-400-036 WAC, “Relocation of portable sources.”..................................... 14

4. Section 173-400-040 WAC, “General standards for maximum emissions.”................. 15

5. Section 173-400-050 WAC, “Emission standards for combustion and incineration 

units.” ............................................................................................................................. 17

6. Section 173-400-060 WAC, “Emission standards for general process units.” .............. 19

7. Section 173-400-070 WAC, “Emission standards for certain source categories.” ........ 19

8. Section 173-400-081 WAC, “Startup and shutdown.” .................................................. 19

9. Section 173-400-091 WAC, “Voluntary limits on emissions.” ..................................... 20

10. Section 173-400-100 WAC, “Registration program.” ................................................... 20

11. Section 173-400-105 WAC, “Records, monitoring, and reporting.” ............................. 21

12. Section 173-400-110 WAC, “New source review (NSR) for sources and portable 

sources.” ......................................................................................................................... 21

13. Section 173-400-111 WAC, “Processing notice of construction applications for sources, 

stationary sources and portable sources.” ...................................................................... 27

14. Section 173-400-112 WAC, “Requirements for new sources in nonattainment areas.” 28

15. Section 173-400-113 WAC, “Requirements for new sources in attainment or 

unclassifiable areas.”...................................................................................................... 29

16. Section 173-400-116 WAC, “Increment protection.”.................................................... 29
v

17. Section 173-400-117 WAC, “Special protection requirements for federal Class I areas.”

.................................................................................................................................... 30

18. Section 173-400-118 WAC, “Designation of Class I, II, and III areas.” ....................... 30

19. Section 173-400-131 WAC, “Issuance of emission reduction credits.” ........................ 30

20. Section 173-400-136 WAC, “Use of emission reduction credits (ERC).” .................... 31

21. Section 173-400-151 WAC, “Retrofit requirements for visibility protection.” ............. 31

22. Section 173-400-171 WAC, “Public notice.” ................................................................ 32

23. Section 173-400-175 WAC, “Public Information.” ....................................................... 32

24. Section 173-400-200 WAC, “Creditable stack height and dispersion techniques.” ...... 33

25. Section 173-400-560 WAC, “General order of approval.”............................................ 33

26. Section 173-400-700 WAC, “Review of major stationary sources of air pollution.”.... 35

27. Section 173-400-710 WAC, “Definitions” .................................................................... 36

28. Section 173-400-720 WAC, “Prevention of signification deterioration (PSD).” .......... 36

29. Section 173-400-730 WAC, “Prevention of significant deterioration application 

processing procedures.” ................................................................................................. 38

30. Section 173-400-740 WAC, “PSD permitting public involvement requirements.” ...... 39

31. Section 173-400-750 WAC, “Revisions to PSD permits.” ............................................ 39

32. Section 173-400-800 WAC, “Major stationary source and major modification in a 

nonattainment area.”....................................................................................................... 39

33. Section 173-400-810 WAC, “Major stationary source and major modification 

definitions.” .................................................................................................................... 40

34. Section 173-400-820 WAC, “Determining if a new stationary source of modification to 

a stationary source is subject to these requirements.”.................................................... 40

35. Section 173-400-830 WAC, “Permitting requirements.”............................................... 40

36. Section 173-400-840 WAC, “Emission offset requirements.” ...................................... 41

37. Section 173-400-850 WAC, “Actual emissions plantwide applicability limitation.”.... 41

38. Section 173-400-860 WAC, “Public involvement procedures.”.................................... 41

IV. Appendices............................................................................................................................ 42
vi

Acronyms and Abbreviations

CAA Federal Clean Air Act

CAAA Federal Clean Air Act Amendments

Ecology Washington State Department of Ecology

EPA U.S. Environmental Protection Agency

NAAQS National Ambient Air Quality Standards

NSR New Source Review

PSD Prevention of Significant Deterioration

RCW Revised Code of Washington

SIP State Implementation Plan

WAC Washington Administrative Act

μg/m3 micrograms per cubic meter
vii

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viii

Executive Summary

Background

Section 110 of the federal Clean Air Act, “State implementation plans for national primary and 

secondary ambient air quality standards,” requires each state to adopt a state implementation plan 

(SIP) to allow the state to comply with these standards. The plan consists mostly of regulations. 

It also includes emissions inventories, attainment demonstrations, permits, and other related 

documents. State regulations approved in the SIP become federally enforceable. When a state 

revises regulations that were previously approved in the SIP, or develops new regulations to be 

included in the SIP, it must submit the regulations to the Environmental Protection Agency 

(EPA) for approval into the SIP. 

Washington State has adopted revisions to portions of its general air pollution regulation, 

Chapter 173-400 of the Washington Administrative Code (WAC). Ecology is proposing to 

submit those changes to EPA for inclusion in the SIP. The purpose of the SIP revision is to meet 

federal Clean Air Act requirements of Title I – Air Pollution Prevention and Control, Part A –

Section 110, Part C, and Part D.

Ecology’s General Air Quality Regulations

Chapter 173-400 WAC, titled “General Air Quality Regulations,” was last submitted and 

approved in the SIP in the 1990s. The state rule has since been revised several times. The latest

revision to Chapter 173-400 WAC was completed in 2012.

Ecology’s submittal to EPA

Ecology is proposing to include in the SIP the portions of the revised Chapter 173-400 WAC that 

are necessary to ensure Washington complies with the federal Clean Air Act. Ecology is only 

proposing that EPA review new or revised sections as a part of this SIP submittal. Ecology is 

not submitting to EPA those sections of Chapter 173-400 WAC that have not changed since the 

last SIP approval and are already either approved or were not approved.

As part of the submittal, Ecology asks EPA to:

• Incorporate new or revised provisions into the SIP, including a significant number of 

housekeeping changes such as updated references, renumbering, and clarifying 

wording.

• Remove outdated provisions and provisions that are not related to the purposes of the 

implementation plan.
ix

What the revisions do

The main differences between the revised rule and the one currently in the SIP are in the New 

Source Review permitting programs:

• The rule currently in the SIP lists the facilities and industries required to apply for a 

minor new source review permit. If a facility or industry is not on the list, or if an air 

quality agency Director or control officer determines it does not need a permit, the 

facility or industry is exempt from permitting. 

The revised rule no longer lists facilities that need a permit. As directed by state law, 

it now lists emission units and activities that are exempt from permitting 

requirements. Potential applicants whose facilities involve emission units and 

activities not on this list must apply for a permit.

• The revised rule contains several streamlined permitting options, including a process 

for issuing a General Order of Approval and a revised process for permitting portable 

sources.

• The revised rule also includes Prevention of Significant Deterioration (PSD) and 

nonattainment area permitting regulations that are designed to match federal 

requirements. If EPA approves the PSD regulations, Washington will have its own 

SIP-approved state PSD program, instead of being delegated authority to issue PSD 

permits under the federal program. The nonattainment area permitting regulations are 

needed for permitting in current and potential nonattainment areas.
I. Introduction

Differences Between the Proposed SIP Revision and Final

SIP Revision

There are some differences between the proposed SIP revision and the final SIP revision. 

Ecology made these changes for the following reasons:

• In response to comments received during the public comment period.

• To ensure clarity and consistency. 

The following content describes the changes and Ecology’s reasons for making them. Where a 

change was made solely for editing or formatting purposes and does not affect the rule language 

proposed for inclusion in the SIP we did not include it in this table.

WAC Section / SIP 

Submittal

Description of the Change Reason for the Change

Executive Summary 

of the SIP Submittal

Ecology has added the following 

sentence to the Executive Summary: 

“The purpose of the SIP revision is to 

meet Federal Clean Air Act requirements 

of Title I – Air Pollution Prevention and 

Control, Part A – Section 110, Part C, 

and Part D. “

In response to comments received 

during the public comment period. 

See Appendix F. Response to 

Comments, Comments A.i.3, D.ii.1, 

D.iii.1, and D.iv.1

Page 19 of the SIP 

Submittal

In the Public Review Draft of the SIP 

submittal, Ecology included an EPA 

letter from 19851. Ecology has removed 

the referenced letter from the final 

submittal. 

This change was made in response 

to a comment received during the 

public comment period. See 

Appendix F. Response to 

Comments, Comment A.ii.2.

Section III.2.b of the 

SIP Submittal

Ecology has removed the following

statement in the SIP Submittal (III.2.b): 

“Remove subsection 173-400-030(89) 

(SIP-approved #76) from the SIP”. 

This statement was an oversight. 

Appendix A and Appendix B 

accurately reflected Ecology’s 

intent and did not need to be 

corrected.

WAC 173-400-050(1) 

and 105(4)

Updated provisions in the rule reference

the 2004 version of Ecology’s Source 

Test Manual. Ecology has included this 

document and an Environmental

Checklist listing this manual for public 

review, as supporting material for this 

SIP revision.

This supporting document was 

omitted in the proposal due to an 

oversight.

 

1

EPA Comment letter to Ecology from Gary L. O’Neil, Director, Air and Toxics Division, EPA Region 10 to Linda 

Brothers, Assistant Director, Office of Hazardous Substances and Air Quality Control, Department of Ecology, Dated 

June 28, 1985. 
2

WAC 173-400-113(3), 

second sentence

Ecology has revised the SIP proposal to 

not include the second sentence in WAC 

173-400-113(3) in the SIP.

In response to a comment received 

during the comment period. See 

Appendix F. Response to 

Comments, Comment C.i.1.

WAC 173-400-

720(4)(a)(i) through 

(iv)

Ecology has revised the SIP proposal to 

not include WAC 173-400-720(4)(a)(i) 

through (iv) in the SIP.

In response to comments received 

during the comment period. See 

Appendix F. Response to 

Comments, Comments D.ii.2, 

D.iii.1, and D.iv.2.

Document Organization

This document has three main sections. Section I includes a list of differences between the 

proposal and final SIP submittal, as well as this subsection on the components of the document. 

Section II below provides background information on Chapter 173-400 WAC and its previous 

approvals in the SIP. This section also discusses Ecology’s statutory authority to develop rules 

to implement Clean Air Act requirements and describes Ecology’s Prevention of Significant 

Deterioration (PSD) permitting program. 

Section III discusses proposed SIP revisions in detail and includes justification for changes to the 

SIP approved regulation.

There are six appendices to this document. A brief description of each appendix is provided 

below: 

Appendix A An overview table offering a quick guide of the status of all sections of the 

rule with regard to the current SIP submittal. WAC sections marked as either 

unchanged since the last SIP revision or as not being submitted in the SIP are 

not a part of this submittal. Only sections that are marked in the columns 

“Revised”, “Removed”, or “New” are being submitted to EPA at this time.

Appendix B A comparison of the SIP-approved rule language and current state adopted 

rule; the differences shown in track changes.

Appendix C WAC 197-11-960 Environmental Checklist for “Amendments to Chapter 

174-400 WAC, General Regulation for Air Pollution Sources” prepared on 

August 2, 2010, listing “Source Test Manual – Procedures for Compliance 

Testing” updated as of September 20, 2004, for public review.

Appendix D Determination of applicability of MTCA exemption to air quality permitting 

programs.

Appendix E Electronic spreadsheet comparing emission units and rates exempt from 

permitting in Washington, some other states, and the EPA Tribal NSR rule.

Appendix F Response to comments received during the public comment period and public 

hearing on the proposal.
3

The following supporting documents are included with this submittal:

 Concise Explanatory Statement. Chapter 173-400 WAC Amendments to Washington’s 

New Source Review Regulations. November 1997.

Ecology’s Publication No. 97-211.

Link: https://fortress.wa.gov/ecy/publications/publications/97211.pdf.

 Concise Explanatory Statement and Responsiveness Summary for the Adoption of 

Chapter 173-400 WAC, General Regulations for Air Pollution Sources. December 2004.

Ecology’s Publication No. 04-02-026.

Link: https://fortress.wa.gov/ecy/publications/publications/0402026.pdf.

 Concise Explanatory Statement. Chapter 173-400 WAC General Regulations for Air 

Pollution Sources. Summary of rule making and response to comments. December 2010. 

Ecology’s Publication No. 11-02-010. 

Link: https://fortress.wa.gov/ecy/publications/publications/1102010.pdf.

 Concise Explanatory Statement. Chapter 173-400 WAC General Regulations for Air 

Pollution Sources and State Implementation Plan Revision: Summary of rule making and 

response to comments. October 2012. 

Ecology’s Publication No. 12-02-024. 

Link: https://fortress.wa.gov/ecy/publications/publications/1202024.pdf.

 “Source Test Manual – Procedures for Compliance Testing” as of September 20, 2004.

Link: http://www.ecy.wa.gov/programs/air/Source_Test/sourcetesthome.html.

II. Background

The federal Clean Air Act and federal regulations require the Washington Department of 

Ecology (Ecology) to have in place specific programs and requirements to protect air quality. 

Section 110 of the Clean Air Act, called “State implementation plans for national primary and 

secondary ambient air quality standards,” requires each state to adopt a state implementation 

plan (SIP) that provides for implementation, maintenance, and enforcement of primary and 

secondary national ambient air quality standards (NAAQS) in the state. SIP-approved programs 

and regulations become federally enforceable. Whenever a state revises regulations that were 

previously approved in the SIP, or develops new regulations to be included in the SIP, it is 

required to submit the regulations to EPA for approval in the SIP. 

The state Legislature enacted Washington’s Clean Air Act, Chapter 70.94 of the Revised Code of 

Washington (RCW) in 1967. This law provides Ecology with the necessary authority to fulfill 
4

the Section 110 requirements of the federal Clean Air Act. Subsection A below contains further 

details on Ecology’s statutory authority as it relates to this submittal. 

Using its authority, Ecology submitted to EPA for inclusion in the SIP: air quality regulations, 

attainment demonstrations, emission inventories, and other documents related to the purposes of 

the SIP. These submittals now comprise the Washington SIP as codified in the Code of Federal 

Regulations (40 CFR Part 52, Appendix WW.) 

Chapter 173-400 of the Washington Administrative Code (WAC), General Air Quality 

Regulations, is a part of the state’s program to implement and enforce NAAQS. Chapter 173-

400 WAC was originally promulgated in 1972 under WAC 18-04. In 1976, the provisions were 

moved to Chapter 173-400 WAC. This chapter underwent numerous revisions over time

reflecting the changes in the air quality management in Washington.

The latest SIP update of Chapter 173-400 WAC took place between 1991 and 1995. Ecology 

submitted the amended Chapter 173-400 WAC to EPA for inclusion in the SIP on May 14, 1991. 

EPA took final action on that submittal on January 15, 1993.

2

 EPA approved Chapter173-400

WAC, as in effect on March 22, 1991, except for:

o WAC 173-400-040(1)(c) and (d) “alternative time periods for opacity standards” 

and “alternative opacity limits”

o WAC 173-400-040(2) “Fallout”

o WAC 173-400-040(4) “Odors”

o The second paragraph of WAC 173-400-040(6) “exemption from sulfur dioxide 

emission limit”

o The exception provision in WAC 173-400-050(3) “alternative oxygen correction 

factor”

o WAC 173-400-070(7) “Sulfuric acid plants”

o WAC 173-400-075 “Emission standards for sources emitting hazardous air 

pollutants”

o WAC 173-400-115 “Standards for performance for new sources”

o WAC 173-400-120 “Bubble rules”

o WAC 173-400-131 “Issuance of emission reduction credits”

o WAC 173-400-136 “Use of emission reduction credits”

o WAC 173-400-141 “Prevention of significant deterioration (PSD)”

o WAC 173-400-180 “Variance”

On March 8, 1994, Ecology submitted to EPA revisions to the 1993 SIP-approved Chapter 173-

400 WAC. On February 22, 19953, EPA proposed to approve in part or disapprove in part the 

revisions. EPA also proposed to not take action on those provisions that were unrelated to the 

 

2

58 FR 4578 (final rule action); 57 FR 44530 (proposed rule action)

3

60 FR 28726 (final rule action); 60 FR 9802 (proposed rule action);
5

purposes of the implementation plan4. EPA took final action on the proposal on June 2, 19955. 

Below is a list of approved and disapproved provisions, and the provisions EPA did not take 

action on (those provisions that were not related to the purposes of the SIP):

 Approved revisions to:

o WAC 173-400-030 “Definitions”

o WAC 173-400-040 “General standards for maximum emissions” (except for -

040(1)(c) and (d); - 040(2); -040(4); and the second paragraph of -040(6))

o WAC 173-400-100 “Registration”

o WAC 173-400-105 “Records, monitoring, and reporting”

o WAC 173-400-110 “New source review (NSR)”

o WAC 173-400-171 “Public involvement”

o WAC 173-400-230 “Regulatory actions”

o WAC 173-400-250 “Appeals”

 Approved new sections:

o WAC 173-400-081 “Startup and shutdown”

o WAC 173-400-091 “Voluntary limits on emissions”

o WAC 173-400-107 “Excess emissions”

o WAC 173-400-112 “Requirements for new sources in nonattainment areas” 

(except for -112(8), which was not submitted for inclusion in the SIP)

o WAC 173-400-113 “Requirements for new sources in attainment or unclassifiable 

areas” (except for -113(5), which was not submitted for inclusion in the SIP)

 Disapproved provisions:

o WAC 173-400-040(1)(c) “alternative time periods for opacity standards”

o WAC 173-400-040(1)(d) “alternative opacity limits”

o The second paragraph of WAC 173-400-040(6) “exemption from sulfur dioxide 

emission limit”

o The exception provision in WAC 173-400-050(3) “alternative oxygen correction 

factor”

o WAC 173-400-120 “Bubble rules”

o WAC 173-400-131 “Issuance of emission reduction credits”

o WAC 173-400-136 “Use of emission reduction credits”

o WAC 173-400-141 “Prevention of significant deterioration (PSD)”

o WAC 173-400-180 “Variance”

 Took no action:

o WAC 173-400-040(2) “Fallout”

 

4

Such as adopting regulations issued in 40 CFR parts 60, and 61 or state plans to implement emission guidelines 

contained in 40 CFR Part 60, subpart C.

5

60 FR 28726
6

o WAC 173-400-040(4) “Odors”

o WAC 173-400-070(7) “Sulfuric acid plants”

o WAC 173-400-075 “Emission standards for sources emitting hazardous air 

pollutants”

o WAC 173-400-115 “Standards for performance for new sources”

 Provisions not submitted for inclusion in the SIP:

o WAC 173-400-112(8)

o WAC 173-400-113(5)

o WAC 173-400-114

Since the last SIP approval, Washington State has adopted revisions to portions of Chapter 173-

400 WAC. Ecology is now proposing to submit those changes to EPA for inclusion in the SIP. 

The primary differences between the revised rule and the one currently in the SIP are in the New 

Source Review permitting programs:

Minor New Source Review Changes

The rule currently in the SIP lists the facilities and industries required to apply for a minor new 

source review permit. If a facility or industry is not on the list, or if an air quality agency 

director or control officer determines it does not need a permit, the facility or industry is exempt 

from permitting. The revised rule no longer lists facilities that need a permit. State law was 

amended to require Ecology to list sources, rather than facilities and industries, which are de 

minimis sources of air pollution. These de minimis sources are exempt from permitting. As a 

result of this change, the revised regulation requires a permit for any emission unit or activity

that is not listed as a de minimis emission source. Potential applicants whose facilities involve 

emission units and activities not on this list must apply for a permit.

Streamlined Permitting Options

The revised rule contains several streamlined permitting options, including a process for issuing 

a General Order of Approval and a revised process for permitting portable sources.

Major New Source Review Program Changes

For major sources in Washington, EPA has a Federal Implementation Plan (FIP) in place to 

implement the Prevention of Significant Deterioration (PSD) program6. Pursuant to 40 CFR

52.21(u), EPA has delegated authority to implement and enforce the federal PSD program to the 

Ecology in a delegation agreement7. The revised rule includes PSD permitting regulations that 

are designed to closely match federal requirements. If EPA approves the PSD regulations, 

 

6

40 CFR 52.2497

7

Agreement for the Delegation of the Federal Prevention of Significant Deterioration (PSD) Regulations by the EPA, 

Region 10 to the State of Washington Department of Ecology, February 23, 2005
7

Washington will have its own SIP-approved state PSD program, instead of being delegated 

authority to issue PSD permits under the federal program. A detailed overview of Ecology’s 

PSD program can be found on the following page 8.

The revised rule also includes nonattainment area permitting regulations. The nonattainment 

area permitting regulations are needed for permitting in current and potential nonattainment 

areas. The regulations closely match federal requirements.

Statutory Authority

The state legislature enacted Washington’s first Clean Air Act (Act) in 1967. The Act is codified 

at Chapter 70.94 RCW. 

As it currently exists, the Act sets out a number of different policies and required actions, and 

specifies:

 the basic hierarchy of regulatory agencies in the state

 the preference for local air pollution control authorities

 requirements for:

o permitting of new sources

o the issuance of air operating permits for some existing sources

o control of open, agricultural, and silvicultural burning

o commute trip reduction requirements

o control of emissions from wood burning appliances (wood fired stoves and 

heaters)

One element of the Act directs Ecology to establish rules to implement the state Clean Air Act 

programs and requirements. In the case of the new source review rules, the Ecology rules apply 

statewide, except where a local clean air agency has implemented its own rules. The Act

specifies that the Ecology and local agency rules do not apply to the energy facilities under the

purview of the Energy Facilities Site Evaluation Council (EFSEC). EFSEC is given primary 

authority for the permitting of energy projects listed in Chapter 80.50 RCW. EFSEC has enacted 

regulations for permitting the projects under its jurisdiction. In the case of permitting stationary 

sources of air pollution, the Act’s intent is that local clean air agencies, EFSEC, and Ecology are 

primarily responsible for implementing programs and rules to control air pollution. 

Since 1967, the Act has been periodically amended. The most significant amendment, since 

Chapter 173-400 WAC was last submitted to EPA in 1993, that affected the activities covered by 

this rule occurred in 1996. Section 70.94.152 RCW was modified in 1996. This change required 

Ecology to develop a listing of sources that would be considered to be de minimis sources of air 

pollutants. These de minimis sources would not require Notice of Construction permits prior to 

the start of construction or operation. 
8

The state law has been amended since 1996, but the amendments do not affect Ecology’s

enforcement authority under the law or the permitting of stationary sources. 

Prevention of Significant Deterioration Program Description

Ecology has been operating a delegated Prevention of Significant Deterioration (PSD) program 

since 1983. Ecology submitted PSD rules to EPA in 1993, but EPA disapproved them and 

reissued a Federal Implementation Plan (FIP). The PSD FIP implements the federal PSD 

permitting program as it exists in 40 CFR 52.21. It has been a goal of Ecology for the past 15 

years to have a SIP-approved PSD program rather than continue to operate a delegated PSD 

program. Ecology has the necessary staff and resources in place to operate the SIP-approved 

PSD program which would comply with requirements in Section 110 of the federal Clean Air 

Act. 

The PSD permitting process in Washington

Ecology is primarily responsible for implementing the PSD program in Washington. The 

EFSEC has separate responsibility to implement a delegated PSD program for the major energy 

facilities under its jurisdiction. The rule (WAC 173-400-700(2)) establishes the relationship of 

the permitting program between Ecology, the local authorities, and EFSEC. 

While Ecology is primarily responsible for issuing PSD permits, we rely on the assistance of the 

local authorities to identify applications they receive which are unclear or rely on the provisions 

of WAC 173-400-720(4)(b)(iii)(D) (revising 40 CFR 52.21(r)(6)) to determine that a project is 

not subject to PSD. The local agencies consult with us or have the applicant work with us to 

determine if the proposed project is or is not subject to PSD permitting. When reviewing these 

analyses, Ecology makes the final decision whether the project as described in the materials 

reviewed is or is not subject to PSD permitting requirements. Ecology charges a review fee for 

making these determinations to recover the costs incurred when making the determination.

If the application is subject to PSD, then Ecology consults with the applicant to identify what 

they must do to submit a complete application. 

The resulting permit application contains information needed to address the emissions of all air 

pollutants; both those subject to PSD permitting and those pollutants subject to state minor 

source permitting requirements. Ecology has a goal to issue all PSD permits on the timeframe 

given in RCW 70.94.152 (application completeness decision within 30 days after applicant 

received, and proposed decision to public comment 30 days after). While the timeframe is a 

target, pursuant to WAC 173-400-730, Ecology has 30 days to determine if the application is 

complete and a year after the application has been determined complete to issue a final approval.

Ecology consults with the local authority with jurisdiction over the applicant to assure the 

emission limitations and Best Available Control Technology (BACT) control decisions made by 
9

both agencies are compatible and capable of being implemented in a minor new source review 

permit, an Air Operating Permit (AOP). Ecology and the local authority coordinate the public 

comment periods on the AOP and the PSD permit to the maximum extent possible. The ideal 

coordination is having both permits addressed in the same public notice and having the same 

comment period. If a hearing is necessary, both permits are addressed in the same hearing.

Ecology and the local authority also work to issue the two permits as close to the same time as 

possible. The Washington State/local authority/EPA Compliance Assurance Agreement 

(Agreement) describes the coordination of enforcement actions between Ecology, the local 

authorities, and EPA. 

Failure to apply for and receive a permit

Per the Agreement, the primary enforcer is the local authority. WAC 173-400-720(3) allows 

Ecology or the local authority to enforce against a source for failure to apply for a PSD permit 

when one is required. 

Violations of terms of an issued permit

Violations of conditions of a PSD permit are normally enforced by Ecology until the PSD permit 

has been incorporated into an AOP. WAC 173-400-720(3)(c) allows the local authority to also 

enforce violations of the PSD permit. As necessary, Ecology and the local authority coordinate 

their enforcement to avoid conflicting or duplicative enforcement actions. Once incorporated 

into the AOP, the local authority that issued the AOP is responsible to enforce the PSD permit 

terms.

Incorporation of the PSD permit into the AOP

PSD permits are applicable requirements of the air operating permit program (definition of 

applicable requirement in WAC 173-401-200(4)). As such, they are incorporated into an AOP 

on the timeframes required by WAC 173-401. 

Ecology resources to implement the program

Ecology has a staff of engineers and air quality modelers to support the review and issuance of 

PSD permits. The permitting and modeling staff currently has 60 years of combined PSD 

permitting experience. 

PSD permit applicants are required to pay permitting fees covering the costs of reviewing the 

application and issuance of the final permitting decision. The permit fees are included in WAC 

173-455 and are subject to periodic revision to reflect the cost of issuing the permits.
10

III. Proposed Revisions to the SIP-Approved Chapter

173-400 WAC

Organization

This chapter of the submittal contains details of the proposed SIP revisions. Each discussion 

describes changes and proposes specific actions for EPA to take. Specifically, each discussion 

covers the following elements: 

a) Description (What is submitted?)

This subsection describes a section of the Chapter 173-400 WAC.

b) Action (What would Ecology like EPA to do with the submittal?)

This section describes one or a combination of actions Ecology may propose:

• Approve revised or new provisions into the SIP

• Remove outdated provisions from the SIP

• Remove currently SIP-approved rules that are not related to the criteria pollutants 

regulated under the SIP or not essential for meeting and maintaining the National 

Ambient Air Quality Standards (NAAQS)

c) Analysis of Submittal

This subsection describes the differences between the SIP-approved rules and the revised 

rules. The analysis may include the following topics as appropriate with more discussion 

where there were key changes:

• Summary of the changes and general differences

• A general description of the sources or source categories affected

• Why the rules were revised. If it is a new rule – why the rule is needed

• The effect of the revision on the NAAQS

• Will the allowable or actual emissions increase, decrease; or be de minimis?

• Were the rules relied on in an attainment or maintenance plan? 

• Are the NAAQS protected?

• Are the Prevention of Significant Deterioration (PSD) Increments protected?

• Is the revised rule consistent with the Visibility SIP?
11

SIP Revisions Discussion

1. Section 173-400-020 WAC, “Applicability.”

a) Description (What is submitted?)

This section describes applicability of the rule to the sources of air pollution in the state. The 

language in subsection 173-400-020(1) WAC was updated in 2012. The revised language 

clarifies the relationship between Chapter 173-400 WAC and corresponding local clean air 

authorities’ regulations.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve revised provisions in the SIP.

c) Analysis of Submittal

This rule clarifies that Chapter 173-400 WAC applies statewide unless a local clean air authority

has adopted and implemented corresponding local rules. These corresponding rules apply only 

to sources subject to local jurisdiction. Each authority is responsible for identifying 

corresponding provisions and submitting them via Ecology to EPA for review and approval into 

the SIP.

This rule update was added in response to EPA Region 10’s request to clarify the relationship 

between Ecology and local authority rules. This rule change is not intended to change allowable 

or actual emission rates or affect implementation and maintenance of the NAAQS. See 2012 

Concise Explanatory Statement8for additional information.

2. Section 173-400-030 WAC, “Definitions.”

a) Description (What is submitted?)

This section contains a list of terms and definitions used throughout the rule. The definitions 

apply statewide unless a local clean air authority or EFSEC has adopted their own definitions.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace outdated section 173-400-030 WAC in the SIP with the updated version, except for the 

following definitions that are in the state rule:

 Do not approve new subsection 173-400-030(91) into the SIP.

c) Analysis of Submittal

Changes to specific definitions are described below. Due to new definitions being added and 

some definitions removed, the numbering in the rule is different from the one in the SIP. For 

example, in the current WAC, definitions related to the federal major new source review 

programs have been removed from this section and now reside in WAC 173-400-720 

(Prevention of Significant Deterioration program) and in WAC 173-400-810 (nonattainment area 

 

8

https://fortress.wa.gov/ecy/publications/publications/1202024.pdf
12

new source review program). The numbering below is based on the numbering in the new rule 

with the exceptions noted.

173-400-030(2) and (79): Class I area visibility protection related definitions were moved to 

section 173-400-117 WAC.

173-400-030(5): The “Allowable emissions” definition was clarified and references were 

updated. This definition is for use in the state minor NSR permitting program and for issuing 

‘synthetic minor’ orders under WAC 173-400-091. The federal major NSR definitions of 

‘allowable emissions’ are found in WAC 173-400-710 and -810.

173-400-030(9): Added “Attainment area” definition.

173-400-030(11): This definition is used in the minor NSR program. The federal definition of 

“Begin actual construction” is adopted by reference in 173-400-710 WAC. 

173-400-030(12): Deleted date of reference. This is the definition of BACT as it exists in state 

law and is used for minor NSR purposes. The federal definition of BACT is adopted by 

reference or included verbatim in WAC 173-400-720 and -810 for use in the major NSR 

programs.

173-400-030(14): This definition was added to support implementation of WAC sections 173-

400-035 and -930. Neither section is proposed for inclusion in the SIP at this time.

173-400-030(18): Clarified that the definition is about “units.”

173-400-030(19)(b): Added clarifying language.

173-400-030(21): Added definition of the “criteria pollutant.” This is not the same as the 

definition of “regulated pollutant” or “regulated NSR pollutant” as used in the federal major 

NSR program.

173-400-030(28): This is a new definition. It is used within our source registration program and 

public involvement requirements. It has no effect on major or minor NSR applicability or 

permitting requirements.

In the registration program, these emission rates are used to determine information submittal and 

inspection schedules. Within the public involvement requirements, the table is used to determine

if the project is subject to a mandatory public comment period under 173-400-171(3)(b).

173-400-030 (32): The “existing stationary facility” definition is listed as 173-400-030(26) in 

the SIP-approved rule. This definition is applicable to visibility protection requirements. The 

revised section -151 makes its inclusion here unnecessary.

173-400-030(34): This is a new definition to support the visibility protection requirements. 

173-400-030(35): Clarifying language.
13

173-400-030(36): This is a new definition to clarify what federally enforceable means.

173-400-030(36)(as listed in the SIP approved rule): This definition is removed since it no 

longer has any regulatory value. Federal Land Managers have never declared any integral vistas 

in Washington’s Federal Class I areas.

173-400-030(37) (as listed in the SIP approved rule): This major NSR definition is now in 

section 173-400-810.

173-400-030 (39), (40), (46) (as listed in the SIP approved rule): These definitions were 

removed as a result of the major NSR program being separated from the minor NSR provisions 

and adoption of federal definitions by reference. They are now included in the major NSR 

definitions found in WAC 173-400-720 and 810. 

173-400-030(42): A new definition to support implementation of 173-400-110(5).

173-400-030(49): Added a new definition for National Ambient Air Quality Standards 

(NAAQS).

173-400-030(50): This NESHAPS definition has some minor language changes.

173-400-030(51): This is a new definition related to NESHAPS. 

173-400-030(54): This definition is 173-400-030(48) in the SIP-approved rule. It defines what a 

New Source Performance Standard (NSPS) is. 

173-400-030(55): Added clarifying language.

173-400-030(56): This definition is used to understand the definition of a stationary source. 

These engines are exempt from the new source review regulations. The definition is used in 

WAC 173-400-035, which is not proposed for inclusion in the SIP. The definition is the same as

the definition in 40 CFR Part 89.

173-400-030(62): This is a new definition. It was added to support significant rate for ozone 

depleting substances added to the PSD definition of “significant.”

173-400-030(66): This is a new definition to be included in the SIP.

173-400-030(67) and (68) (as listed in the SIP approved rule): These definitions were moved to 

different sections of the rule. The definition of “significant” under (67) was moved to 173-400-

720 WAC. The definition of “significant visibility impairment” was moved to 173-400-

117(1)(a) WAC. 

173-400-030(70) and (71): These are new definitions. They define PM2.5 and PM2.5 emissions. 

These definitions were added in response to the PM2.5 NAAQS set by EPA in 1997. The 

definitions are based on the definitions in 40 CFR Parts 50 and 51.
14

173-400-030(72): This is a new definition to be included in the SIP. The definition is used in 

the permitting program for portable stationary sources in WAC 173-400-036.

173-400-030(73): Clarifying changes.

173-400-030(79): This is the definition in 40 CFR 51.165. This definition conforms to the 

results from a federal court decision (Natural Resources Defense Council v. U.S. EPA, 725 F.2d 

761 (D.C. Cir. 1984)) rather than the definition persisting in federal regulation. This is not the 

definition in the EPA’s major NSR definitions in 40 CFR 51.166, Part 51 Appendix S, or 52.21.

173-400-030(80): This definition now follows state law rather than EPA regulation. The federal 

definition is used for the major NSR programs.

173-400-030(85): This is a new definition to be included in the SIP.

173-400-030(88): This is a new definition to be included in the SIP.

173-400-030(91): This definition is for a toxic air pollutant. Toxic air pollutants are not a part 

of the SIP. We ask EPA to not include it in the SIP.

173-400-030(92): This is a new definition to be included in the SIP.

173-400-030(94): Clarifying changes. 

173-400-030(95): This definition was current with the definition in 40 CFR 51.100 at the time 

of the most recent adoption date of Chapter 173-400 WAC. EPA has since added additional 

chemicals to the listing of chemicals that are not VOCs, making our definition no longer current

with the latest changes in the federal requirements. The definition will be updated when this 

section of the rule is reopened for revision. In the meantime, we propose to include this version 

in the SIP as it is more in conformance with the federal requirements than the currently approved 

SIP definition.

3. Section 173-400-036 WAC, “Relocation of portable sources.”

a) Description (What is submitted?)

This is a new section adopted into the state rule in 2012. This section regulates portable sources. 

Originally, these sources were a part of the SIP-approved rules under WAC 173-400-110(5). 

The new section is applicable statewide for all authorities that participate in the program. 

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section in the SIP.

c) Analysis of Submittal

This section outlines a simplified and expedited approval process for sources that are portable 

and frequently move. 

The source must have a notice of construction (NOC) from some permitting authority in the 

state, but not necessarily from the jurisdiction in which they are locating. A short notice (15 

days) given to the permitting agency attests that a source meets:
15

 New Source Performance standards

 Best available control technology

 National emission standards for HAPs

 NAAQS

 Major source regulations

4. Section 173-400-040 WAC, “General standards for maximum 

emissions.”

a) Description (What is submitted?)

This section was revised four times (2000, 2001, 2005, and 2011) since it was last approved into 

the SIP in 1993. Major changes include new exemptions from the twenty percent opacity 

standard analyzed below. 

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the revised and new portions of the section into the SIP, except for:

 WAC 173-400-040(2)(c) and (d)

 WAC 173-400-040(3)

 WAC 173-400-040(5) 

 WAC 173-400-040(7), second paragraph

These provisions were not approved in the SIP previously9and Ecology does not propose to 

include them in the SIP at this time.

c) Analysis of Submittal

WAC 173-400-040(2)(e)(i) – Visible emissions reader certification testing. 

This is an exemption from the standard to allow for certification of readers per 40 CFR Part 60 

Appendix A, Method 9. The reader certification testing protocol requires opacity to be above 

20% enough times in an hour to violate the opacity standard in WAC 173-400-040(2), which is 

currently part of the SIP. During the certification testing, the opacity standard contained in 

various EPA rules would also be exceeded. The reader certification process dictated in Part 60, 

Appendix A, Method 9 requires values above the standard as part of the testing process. 

Visible emissions reader certification is a necessary qualification for air quality control staff and 

compliance staff employed by sources. The staff needs to determine compliance with visible 

emissions standards in permits. In establishing this exemption, we reviewed the 2 days per year 

(each day approximately 6 months apart) that the reader certification testing occurs at a given 

location to be a de minimis activity. 

 

9

60 FR 28726
16

WAC 173-400-040(2)(e)(ii) - Military training exercises.

Military training using obscurants is a necessary component of national defense. The obscurants 

used are either an oil fog or a pulverized material such as graphite. Specialized equipment 

mounted on the rear of Humvees, mortar shells, smoke pots, and smoke grenades are used to 

generate the obscurants and to distribute them across the mock battlefield being used for training. 

The presence of obscurants emanating from a discrete source (such as a smoke pot) could be 

classified as a violation of the state opacity standard.

Prior to the inclusion of this training in rule, in 2001 the Army completed environmental 

assessments (EAs) of the effects of obscurant training with various kinds of smoke generators on 

Fort Lewis and at the Yakima Training Center10. The EAs evaluated issues such as obscurant 

dispersion, density, allowable distances from site boundaries, and prevention of adverse offsite 

impacts. These EAs formed the basis for our inclusion of the opacity exemption in our rules. 

The results indicated that no offsite exceedance of a NAAQS would occur with adherence to the 

location usage criteria within the EAs. 

With the assistance of the Army, the results of the EAs, and three local air pollution control 

authorities, specific requirements to control/reduce the offsite impacts from obscurant training 

were developed and included in the rule text. One paramount criterion is the tracking of weather 

conditions—a training is then canceled if wind patterns change such that the obscurant could 

travel beyond the boundaries of the military site/reservation. 

The exemption requires the Army to perform training under specified conditions given in the 

exemption. 

On January 18, 2012, EPA approved for the State of Colorado’s SIP a similar exemption 

(contained in 5 CCR 1001-3 II.D11) for the use of obscurants during military training exercises at 

two military bases in Colorado. 

WAC 173-400-040(2)(e)(iii) – Firefighter training.

State law (primarily RCW 70.94.6546) allows for firefighter training to occur in certain areas of 

the state without a state issued permit. In all other areas of the state, instructional fires may be 

allowed when permitted by the local air pollution permitting authority. The implementation of 

the state law for fire fighter training is codified in rule within WAC 173-425, Open Burning, 

which implements both the exemption for some fires under RCW 70.94.6546 (formerly codified 

at RCW 70.94.650) and the requirements of RCW 52.12.150, Setting fires for firefighter 

instruction -- When burning permit not required -- Notice, inspection required. RCW provisions

limit the areas covered by the exemption and restrictions on burning. For example, a fire cannot 

 

10 The Department of the Army, Headquarters I Corps and Fort Lewis produced environmental assessments and 

Findings of No Significant Impact of their obscurant training practices in 1999 and in 2001 for training activities on 

Fort Lewis and the Yakima Training Center. Copies can be made available.

11 77 FR 2466
17

be located in an area subject to an emergency episode. There are also requirements in place to 

minimize the emissions and associated air quality impacts.

Fire fighter training by fighting real fires is a necessary function and training activity for 

minimizing the loss of life and protecting private and public property. State law exempts this 

activity from air quality requirements and this opacity exemption merely completes the 

exemptions in rule.

Firefighter training occurs at either discrete facilities (firefighter training centers) constructed 

and operated for the training of firefighters or existing structures destined for demolition. 

Firefighter training centers have been permitted by local air pollution control authorities. The 

permitting process included an evaluation of the ambient air quality impacts of the training 

center and setting any necessary operational limitations to protect ambient air quality. 

Firefighter instruction using existing structures is also exempted from the opacity standard. 

These fires are subject to the review process under WAC 173-425. These fires are intentionally 

set by a fire department specifically for the purpose of using real buildings for training. When 

using an existing structure, all asbestos and similar hazardous materials are removed prior to the 

training exercise. Typically, such training takes less than a single day. Such training occurs on 

an opportunity basis, with the existing structures used for training being scattered through each 

fire jurisdiction. 

The exemption from meeting the opacity standard during firefighter training fires implements the 

state laws addressing this training.

5. Section 173-400-050 WAC, “Emission standards for combustion and 

incineration units.”

a) Description (What is submitted?)

This section of Chapter 173-400 WAC has been revised three times (2001, 2005, and 2011) since 

it was adopted in the SIP in 1993. This section has three subsections that were approved in the 

SIP in 1993. Subsection 173-400-050(1) has been revised to include updated references and 

some minor language changes. Subsection 173-400-050(2) does not regulate criteria pollutants 

and thus does not belong in the SIP. Subsection 173-400-050(3) has been revised to include 

some minor language changes and clarification on determination of an alternate oxygen 

correction factor. 

b) Action (What would Ecology like EPA to do with the submittal?)

Replace subsections 173-400-050(1) and (3) with the updated version of the rule, including the 

text that was not approved in the SIP during the last review. 

Remove subsection 173-400-050(2) WAC from the SIP. 

Take no action on other subsections not listed above.
18

c) Analysis of Submittal

The revisions to subsection (1) and (3) do not affect emission rates or interfere with 

implementation or maintenance of the NAAQS. Subsection (1) contains an updated reference to 

“Source Test Manual – Procedures for Compliance Testing” as of September 20, 200412. This 

manual was a part of the Chapter 173-400 rulemaking in 2004 and was listed in the 

Environmental Checklist13 (WAC 197-11-960) for public review. Ecology submits the manual 

and Environmental Checklist to EPA as supporting documents.

Subsection (3) establishes a default oxygen correction factor for reporting concentrations of air 

pollutants in exhaust gases. The section was revised to include criteria on how to modify this 

correction factor in circumstances where the default value of 7% is inappropriate, such as when 

implementing NSPS and NESHAP standards. For example, the correction factor for combustion 

turbines in 40 CFR Part 60 subparts GG and KKKK is 15%14, the factor in Part 60 Subpart BB15

is 10%, and the factor in Part 60 subpart Db16 is 3%. 

Subsection (2) is involved with regulating emissions from incinerators that are not subject to 

regulation under the state solid waste incinerator rule or under federal NSPS rules that have been 

adopted by the state. This section of the rule dates from the past when small incinerators at 

grocery stores, apartment buildings, etc, were common. These incinerators produced dense 

smoke and odors resulting from poor combustion. Ecology plans to remove this outdated section 

from the rule upon EPA’s approval of its removal from the SIP.

Ecology requests EPA to remove WAC 173-400-050(2) from the SIP. Total carbonyls are not a 

criteria air pollutant and are not required to be included in the SIP. However, to the extent that 

the carbonyls captured by this limitation and Ecology’s test method those carbonyls are 

measured as Volatile Organic Compounds (VOCs), they will be included in VOC analyses and 

emission limitations. Similarly, if there are condensable or particulate carbonyls, they will be 

included as part of the particulate emissions from a source. As a result, removal of the specific 

pollutant total carbonyls from the SIP will not reduce the ability of the state or EPA to regulate 

VOC or particulate emissions in Washington, to the extent any of these sources remain.

 

12 This document is also available on Ecology’s Web Site at: 

http://www.ecy.wa.gov/programs/air/Source_Test/sourcetesthome.html

13 See Appendix C

14

 Respectively 40 CFR 60.332(a) and 40 CFR Part 60 Subpart KKKK Table 1

15

 40 CFR 60.283(a)(1)

16 40 CFR 60.48b(j)(4)(i)(A)
19

6. Section 173-400-060 WAC, “Emission standards for general process 

units.”

a) Description (What is submitted?)

This section was approved into the SIP in 1993. The state revised the section in 1998, 2000, 

2001, and 2005. The revisions include an updated reference to EPA test methods and a minor 

word change.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version in the current state rule.

c) Analysis of Submittal

The revisions are administrative. They do not change the allowable emission rates and do not 

interfere with implementation or maintenance of the NAAQS.

7. Section 173-400-070 WAC, “Emission standards for certain source 

categories.”

a) Description (What is submitted?)

This section was approved into the SIP in 1993. The state revised the section in 1996, 1998, 

2000, 2001, 2011, and 2012. SIP-approved subsections have had some language clarification 

changes and updated references in the revisions. A new subsection, (8), is Ecology’s adoption of 

the §111(d) emission guideline for municipal solid waste landfills constructed, reconstructed, or 

modified before May 30, 1991. 

b) Action (What would Ecology like EPA to do with the submittal?)

Replace subsections (1), (2), (3), (4), (5), and (6) with the revised sections in the current state 

rule.

Subsection (7) was not approved into the original SIP in 1993 and Ecology does not propose it 

for approval at this time. 

Ecology does not propose to include new subsection (8) in the SIP.

c) Analysis of Submittal

The changes to the SIP-approved subsections include language clarifications and reference 

updates. Subsection (7) does not address criteria pollutants required under the SIP. Subsection 

(8) is an emission guideline under Section 111 of the Clean Air Act. These provisions do not 

belong in the SIP.

8. Section 173-400-081 WAC, “Startup and shutdown.”

a) Description (What is submitted?)

Minor revision to existing SIP-approved section of regulation.
20

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version in the current state rule.

c) Analysis of Submittal

No substantive changes. It applies to both minor and major NSR permitting.

9. Section 173-400-091 WAC, “Voluntary limits on emissions.”

a) Description (What is submitted?)

Minor revision to existing SIP-approved section of regulation.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version in the current state rule.

c) Analysis of Submittal

Predominantly language clarification changes. The changes apply to both minor and major NSR

permitting and limiting the emissions of federal Hazardous Air Pollutants. 

10. Section 173-400-100 WAC, “Registration program.”

a) Description (What is submitted?)

The registration program was approved into the SIP in 1993 under section number 173-400-100 

WAC. Ecology has since significantly revised this section and the registration program, which is 

now contained in sections 173-400-099 through 104 WAC. The registration program is a state 

procedural requirement.

b) Action (What would Ecology like EPA to do with the submittal?)

Remove section 173-400-100 WAC from the SIP. Ecology does not propose to include new 

sections 173-400-099 through 104 WAC in the SIP.

c) Analysis of Submittal

SIP-approved section 173-400-100 WAC contains Ecology’s registration program for sources of 

air contaminants, as it existed in early 1990s. This section listed all source categories required to 

acquire permits prior to the start of construction. The section also allowed for an unlisted source 

to be required to get a permit based on a decision of the permitting authority.

The registration program in the current state rule is not linked to the NSR program, does not 

impose control requirements on the sources, and does not enforce or implement federal air 

quality standards. As such, it is not appropriate or required to be included in the SIP17. The 

registration program is no longer linked to NSR applicability. 

 

17 See guidelines for including rules in implementation plans in the “State Implementation Plan Process 

Improvement Project” Final Report, Appendix 2. 

http://yosemite.epa.gov/r10/airpage.nsf/webpage/Region+10+SIP+Process+Improvement+Project+(SIP-PIP)
21

11. Section 173-400-105 WAC, “Records, monitoring, and reporting.”

a) Description (What is submitted?)

Revisions to existing SIP-approved section of the regulation.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version in the current state rule.

c) Analysis of Submittal

The revision establishes more detailed requirements on Continuous emissions monitoring (CEM)

data for installed CEMs that are not required in federal standards such as NSPS, NESHAPS, or 

NESHAPS for Source Categories (MACT). The replacement text strengthens the criteria and 

requirements for installed CEMs.

Section 173-400-105, “Records, monitoring, and reporting,” contains legally enforceable 

provisions implementing the requirements found in 40 CFR 51. Specifically, section 173-400-

105 WAC contains legally enforceable procedures requiring owners or operators of stationary 

sources to maintain records on the type and quantity of emissions from the source and 

periodically report to the permitting authority. The owner(s) or operator(s) of any air 

contaminant source are required to submit an inventory of emissions from the source each year. 

Ecology collects the emission data from all sources regulated by Ecology and all permitting 

authorities in Eastern Washington. This information is included in the annual emission inventory 

report that Ecology submits to EPA. Section 173-400-105 WAC is being submitted for inclusion 

in the SIP as a part of this SIP revision. A previous Ecology submittal to EPA erroneously 

stated the emissions reporting requirement in WAC 173-400-105 was restricted to major sources. 

The rule text contains no such restriction, and any source can be required to submit emissions 

information based on this section of rule.

WAC 173-400-105(4) contains an updated reference to “Source Test Manual – Procedures for 

Compliance Testing” as of September 20, 200418. This manual was a part of the Chapter 173-

400 rulemaking in 2004 and was listed in the Environmental Checklist (WAC 197-11-960) for 

public review.

12. Section 173-400-110 WAC, “New source review (NSR) for sources and 

portable sources.”

a) Description (What is submitted?)

This rule section is used to determine which sources of air pollution are required to obtain 

preconstruction permits prior to the start of construction or restarting after a modification. The 

section identifies which permitting programs (minor NSR, PSD, or nonattainment NSR) are 

 

18 This document is also available on Ecology’s Web Site at: 

http://www.ecy.wa.gov/programs/air/Source_Test/sourcetesthome.html.
22

applicable to a specific project. Local air quality authorities are responsible for most NSR in their 

jurisdictions. Local authorities may either use Ecology’s regulations or write their own. 

This section has been significantly revised since the last approval in the SIP. The bulk of the 

revisions are directed toward: a) clarifying what sources must undergo NSR; and b) identifying

which types of NSR approvals a particular project must obtain prior to the start of construction.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version of the current state rule, except for:

 Ecology does not submit the following new subsections for inclusion in the SIP:

o 173-400-110(1)(c)(ii)(C)

o 173-400-110(1)(e)

o 173-400-110(2)(d)

o the part of WAC 173-400-110(4)(b)(vi) that says “not for use with materials 

containing toxic air pollutants, as listed in chapter 173-460 WAC,”

o 173-400-110(4)(e)(iii) “where toxic air pollutants as defined in chapter 173-460 

WAC are not emitted”

o 173-400-110(4)(f)(i) “that are not toxic air pollutants listed in chapter 173-460 

WAC.”

o 173-400-110(4)(h)(xviii) “, to the extent that toxic air pollutant gases as defined 

in chapter 173-460 WAC are not emitted”

o 173-400-110(4)(h)(xxxiii) “where no toxic air pollutants as listed under chapter 

173-460 WAC are emitted”

o 173-400-110(4)(h)(xxxiv) “, or ≤ 1% (by weight) toxic air pollutants as listed in 

chapter 173-460 WAC”

o 173-400-110(4)(h) (xxxv) “or ≤ 1% (by weight) toxic air pollutants”

o 173-400-110(4)(h) (xxxvi) “or ≤ 1% (by weight) toxic air pollutants as listed in 

chapter 173-460 WAC”

o 173-400-110(4)(h)(xl) Second sentence

o In Table 173-400-110(5) Exemption Levels Table, last row. Ecology does not 

submit the Toxic Air Pollutant de minimis level to be approved into the SIP.

c) Analysis of Submittal

(1) NSR Reform Project

Ecology began the NSR Reform Project to revise the program and establish a listing of de 

minimis sources of emissions in 1995. As Ecology worked with interested parties, a set of 

conceptual and technical issues emerged.

19 As the result of the reform, Ecology made the 

following conceptual changes to its NSR program:

 

19 For the list of issues and details, see 1997 Concise Explanatory Statement: 

https://fortress.wa.gov/ecy/publications/publications/97211.pdf
23

 Clarified the relationship between state and local NSR programs- Ecology clarified that 

its rules apply state-wide unless a local authority adopts its own rules and those rules are 

adopted into the SIP.

 List of exempted equipment- Ecology fulfilled part of its requirements under Chapter 67, 

Laws of 1996 (RCW 70.94.152(10)-(12)) by categorically listing equipment that is 

exempt from NSR and not subject to any administrative requirements.

 De minimis thresholds- See additional discussion below.

 Remove a list of sources that is always subject to NSR- Ecology’s original intent was to 

have a list of exemptions, a list of units that must always go through NSR, and emission 

thresholds by which to judge all non-listed units. Several drafts were written using this 

approach, but they were unclear. Because the Legislature directed Ecology to establish 

de minimis exemptions and required that all sources required to file a Notice of 

Construction must show they will use BACT, Ecology decided to use the exemption list 

only. Ecology removed a list of units that must always go through NSR from the rule. 

The effect of this change is to require all sources that are not exempt, either by listing or 

threshold, to file an NOC and use BACT.

(2) WAC 173-400(110)(1)(e)

The exemption specified in this subsection is based on the statutory exemption for toxic cleanup 

site remedial actions under Chapter 70.105D RCW, Model Toxics Control Act (MTCA). Under 

this exemption, sources are exempt from state and local procedural requirements contained in 

RCW 70.94, or implementing state and local regulations. Federal procedural requirements are 

not subject to this exemption. 

The Director of Ecology determined20, pursuant to RCW 70.105D.090(2), that Ecology cannot

use the MTCA exemption for federally-required air emissions permits. Remedial actions at 

MTCA cleanup sites that are sufficient to trigger the need for the following permits are not 

exempt: Title V air operating permits (AOPs), prevention of significant deterioration permits 

(PSD permits), or nonattainment new source review permits (nonattainment NSR permits). 

Ecology’s minor new source review (NSR) program incorporates federal requirements by 

requiring eligible sources to obtain a permit (Notice of Construction Order of Approval). In 

order to include the exemption from state and local procedural requirements for remedial actions 

which emissions are subject to minor new source review, Ecology must show that the emissions 

from subject sources are sufficiently de minimis that failure to permit this category, along with 

consideration of other source categories and emission units exempt from Ecology’s minor NSR 

program, would not interfere with attainment or maintenance of the NAAQS or violate 

applicable portions of the SIP control strategy as provided in 40 CFR 51.160. Because of 

variability within the source category, such demonstration is difficult. An alternative would be 

to show how those sources would still meet federal procedural requirements if they are exempt 

 

20 See Appendix D.
24

from permitting. The showing must include enforceable procedures. At this time, the rule 

language in WAC 173-400-110(1)(e) does not allow for differentiation between state and federal 

procedural requirements in the minor NSR program. Thus, Ecology does not submit this 

exemption in the SIP at this time. 

The Director of Ecology determined21, pursuant to RCW 70.105D.090(2), that until the MTCA 

exemption for minor source permits is approved in the SIP, application of the minor NSR permit 

exemption RCW 70.105D.090(1) to remedial actions at MTCA cleanup sites that emit NAAQS 

pollutants or their precursors would result in the state’s loss of federal authorization to 

implement these CAA permitting requirements in Washington. This determination applies solely 

to NAAQS pollutants that would be emitted into the air from remedial actions at MTCA cleanup 

sites and is not intended to apply to any other circumstance.

(3) WAC 173-400-110 (4) and (5), “De minimis emission rates 

and emission units/sources.”

Historically, the New Source Review (NSR) rules required 1) all new sources listed as being 

required to register with the state or the local air pollution control authority and 2) existing 

sources being modified and having emission increases to undergo permitting and receive an 

order of approval prior to construction. State law was amended in 199622 to require Ecology 

develop a listing of de minimis emission sources which would not require a permit. The 

development of a de minimis source list and de minimis emission thresholds allows for some 

minor changes at a facility without triggering NSR requirements. Ecology defined de minimis 

levels (thresholds) for the NSR Program. The de minimis emission source listing is comprised of 

two parts: 1) a list of exempt equipment and 2) an annual emissions threshold level for non-listed 

equipment and modifications. The emission threshold is equal to five percent of the Prevention 

of Significant Deterioration (PSD) significance levels defined in 40 CFR 52.21(b)(23), as they 

existed in 1997. 

Background

Ecology began the NSR Reform Project in 1995. Ecology worked with interested parties to 

produce a set of refined conceptual issues prior to beginning the formal rulemaking process. In 

1996, the Washington State Legislature amended the Washington Clean Air Act and directed that 

Ecology establish de minimis exceptions to the state's NSR program. 

Ecology added this directive to the issue resolution phase of rulemaking process already 

underway. The Concise Explanatory Statement for Chapter 173-400 WAC Amendments to 

Washington's New Source Review Regulations (November 1997) outlines Ecology's "conceptual 

framework" analysis and further describes the process used to identify de minimis exemption 

levels. 

 

21 See Appendix D.

22 RCW 70.94.152
25

De Minimis Framework 

Ecology developed two de minimis pathways to satisfy a legislative directive, which were 

included in the NSR regulations adopted in 1997. Upon initial review and evaluation, de 

minimis levels appeared to apply best to equipment, resulting in an exempted equipment list. 

Ecology soon discovered, however, that it became impossible to list all equipment and 

modifications. To fill this gap, Ecology also identified and proposed emission threshold levels 

for non-listed equipment and modifications.

23

De minimis Equipment: Ecology developed an initial list using a combination of typical 

equipment from registration sources and the de minimis activities exempted from permitting by 

other states. Ecology then asked industry to review and comment on the list. The list was also 

distributed for review to local air authorities and representatives from the environmental 

community. The resulting equipment list was very similar to the lists of insignificant emission 

units found in Chapter 173-401 WAC. Additionally, Ecology evaluated whether a unit should be 

de minimis using emissions thresholds and historical permitting requirements. Ecology reached 

the determination that units passing both criteria were also placed on the de minimis list.

24

De Minimis Criteria Pollutant Threshold Levels 

As stated above, Ecology discovered that identifying all equipment and modifications became 

impossible and another method was needed to supplement the equipment list. Ecology evaluated 

and ultimately chose de minimis threshold levels for criteria pollutants as levels equal to 5% of 

the Prevention of Significant Deterioration (PSD) significance levels defined in 40 CFR

52.21(b)(23), as it existed in 1997. 

Since 1997, both the de minimis equipment list and the de minimis emission rates were 

modified. The de minimis equipment list had minor additions, deletions, and changes in 

threshold sizes. The de minimis emission rates were modified to include a greenhouse gas and a 

PM2.5 emission threshold. The PM2.5 threshold is based on the 5% of the PSD significance 

threshold for PM2.5. The current greenhouse gas emission threshold is the same as the PSD 

threshold.

Comparison of de minimis emission rates and equipment to SIP approved de minimis standards

There are many other states in the U.S. that have instituted programs that exempt certain sources 

from permitting requirements based on emission rates, specific equipment, or type of activity. 

Ecology compared its de minimis requirements to the de minimis requirements approved into the 

SIPs of 12 other states, chosen more or less at random. All 12 states are outside of EPA’s 

Region 10 jurisdiction.

 

23 See p. 9 of the 1997 Concise Explanatory Statement available at: 

https://fortress.wa.gov/ecy/publications/publications/97211.pdf

24 Detailed discussions on pages 9 & 10 of the 1997 Concise Explanatory
26

Most of these states have a de minimis emission rate threshold above which NSR permitting is 

required. The de minimis rates of these other states vary considerably, but all are higher than the 

rates in WAC 173-400-110(5). The states reviewed almost all utilize the thresholds in 40 CFR

51.166(b)(21) to define when to require minor NSR permits. Separately, the Tribal Permitting 

rule at 40 CFR 49.153(b)(3) Table 1 exempts from permitting sources with emissions larger than 

exempted by Ecology.

A comparison of de minimis emission units and equipment and activities from 12 other states 

plus EPA’s national Tribal Air Rule is part of the submittal information at Appendix E. In most 

cases, similar trivial activities and sometimes non-trivial emission units and activities are

exempted from permitting. The various exemption lists clearly reflect the priorities of the states 

and the mix of industries they host. There are many categories that are the same (usually with 

Washington having the smallest threshold size, when applicable), but most de minimis 

equipment lists are different. As noted, the differences clearly reflect the mix of industries in a 

particular state, the relative activism of particular industrial groups, and differences in scale of 

some industrial activities. For example, there are states that exempt sawmills from permitting 

requirements, or exempt them if they are below a specific size or emission rate threshold. Many 

states have an exemption for certain kinds of graphic arts and printing activities, while 

Washington does not.

Criteria Pollutant Modeling and Results

Ecology evaluated this threshold level to determine the likely "overall- effect" on pollution levels 

in the state. Ecology started by applying the 5% of PSD criteria to the various criteria pollutant 

emissions data. The end product was a chart identifying the state-wide emission threshold levels 

for specific criteria pollutants. 

Ecology then identified the threshold levels for insignificant emission units and modeled these 

levels using EPA's SCREEN 3 model. Ecology applied conservative parameters for the model, 

which are specifically identified in the 1997 Concise Explanatory Statement. Ecology compared 

the modeling results with the NAAQS. The modeling indicated that the de minimis emission 

rates and insignificant emission units would not cause or contribute to an exceedance of the 

NAAQS. 

As a final step, Ecology evaluated and compared the proposed de minimis emission rate, based 

on 5% of the PSD significant emission rate levels, with what other states included in their rules. 

Washington’s proposed de minimis emission rate fell in the middle range of the de minimis 

levels found in other states. 

Given all the factors, Ecology concluded that using 5% of the PSD significant emission rate as a 

threshold is a reasonable de minimis level for criteria pollutants. 
27

Comparison to ambient monitoring results

Over the past 15 years, Washington State has come into attainment for all NAAQS, with one 

exception. This occurred while implementing the exemptions from minor NSR permitting in the 

state rule and in individual local agency regulations. While not definitive, this is an indication 

that the exemptions from permitting are not impeding our ability to assure the quality of the air 

in Washington continues to improve. 

The one exception is the Tacoma PM2.5 nonattainment area. This area is nonattainment primarily 

due to particulate from wood-fired residential heating, not industrial/commercial activities that 

could utilize the equipment exempted from permitting. 

The current (2012) design values for all the ambient monitors (except Tacoma “L” Street) in the 

state are below the ambient standards25. This also indicates that the permitting exemptions are 

not having an adverse impact on state and local authorities’ ability to meet the ambient standards.

Conclusion

Washington State defined de minimis levels for the NSR Program using a combination of 

methodologies and approaches. Through a multi-step evaluation process, Ecology concluded the 

best approach features an equipment exemption list and a criteria pollutant threshold level for 

non-listed equipment and modifications. In 1997, Ecology adopted rules identifying de minimis 

levels–an equipment exemption list and a 5% of PSD levels threshold for criteria pollutants. 

Use of the rule has not resulted in an increase in incidence of nonattainment. Since 1997, all 

areas of the state were returned to attainment for all pollutants. All Washington permitting 

authorities have utilized the de minimis emission unit and emission threshold concepts in their 

permitting. Even though NAAQS have become more stringent, Washington State still attains the 

NAAQS (with one exception). 26

13. Section 173-400-111 WAC, “Processing notice of construction 

applications for sources, stationary sources and portable sources.”

a) Description (What is submitted?)

A new section of regulation addressing how to process Notice of Construction applications 

(minor NSR).

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP, except for:

 

25 2012 Ambient Air Monitoring Network Report, Ecology Report No 12-02-008.

26 The Tacoma-Pierce County area has become nonattainment for PM2.5 due to home heating emissions. It had not 

been in violation of the PM2.5 NAAQS before.
28

 173-400-111(3)(h) and (i) – references to different chapters of the WAC that are not a 

part of the SIP.

 The part of 173-400-111(8)(a)(v) that reads “and 173-460-040,” – this reference is to a 

different chapter of the WAC that is not a part of the SIP.

 173-400-111 (9) – fees provision required under a different chapter of the WAC that is 

not a part of the SIP.

c) Analysis of Submittal

The new section is composed of the permit processing and issuance criteria formerly located in 

WAC 173-400-110, 112, and 113. These permit processing and issuance criteria are now 

gathered into one location rather than being distributed in multiple locations in the rule, for the 

convenience of both the permitting authority and the permit applicants. Application and permit 

processing steps are clearly delineated in the section, including references to the other sections of

the rule that describe the requirements. 

14. Section 173-400-112 WAC, “Requirements for new sources in 

nonattainment areas.”

a) Description (What is submitted?)

Revision to existing SIP-approved section of regulation.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version of this section in the current state rule,

except for:

 173-400-112(8) – This subsection was not approved in the SIP in 1993. Ecology 

removed this language from the state rule.

c) Analysis of Submittal

In the SIP-approved state rule, this section contains all of the permitting requirements (including 

applicable definitions) for nonattainment permitting. Subsequent to approval in the SIP, EPA 

significantly revised the permitting requirements for nonattainment areas, including 

implementation of the 2002 NSR Reform requirements. 

On the whole, the nonattainment NSR permitting program and requirements have been moved to 

WAC 173-400-800 through -850. The intent of the current form of Section 112 is to point to the 

various requirements in other sections of Chapter 173-400 WAC, including the major 

nonattainment NSR permitting program WAC 173-400-800 through -850.
29

15. Section 173-400-113 WAC, “Requirements for new sources in 

attainment or unclassifiable areas.”

a) Description (What is submitted?)

All of this section has been revised since SIP-approval in 1993. All subsections in the section 

are being submitted except for (5), which addresses requirements for permitting of toxic air 

pollutants located in Chapter 173-460 WAC. The reference to Chapter 173-460 WAC is not part 

of the SIP now since it addresses permitting of toxic air pollutants.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the revised section27 except for the second sentence in subsection (3).

c) Analysis of Submittal

To be consistent with the U.S. Court of Appeals for the District of Columbia decision in Sierra 

Club v. EPA, 705.F.3d 458, Ecology is not submitting the second sentence in WAC 173-400-

113(3) to EPA for inclusion in the SIP. For additional details, please see discussion in Section 

173-400-720 WAC, “Prevention of signification deterioration (PSD).” on page 36 of this 

document.

Significant changes and clarifications were made to section (4) which implements 40 CFR

51.165(b). The changes enable the state rule to better match the requirements in federal rule. 

The rule revision clarified the requirement that each major new source cannot cause or contribute 

to an ambient air quality standard violation.

Subsection (5) (as numbered in the approved SIP) is not part of the SIP-approved regulation now 

and is not proposed for submission to EPA. 

16. Section 173-400-116 WAC, “Increment protection.”

a) Description (What is submitted?)

New section of regulation requiring PSD Increment protection in the state.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

The new section implements increment protection and correction requirements found in 40 CFR

51.166(a). This section includes allowable exemptions from increment protection contained in 

40 CFR 51.166(f).

 

27 Subsection (5) is no longer a part of this subsection. It was relocated to Section 173-400-110 WAC; it was not 

submitted previously and continues to be excluded from the SIP.
30

17. Section 173-400-117 WAC, “Special protection requirements for 

federal Class I areas.”

a) Description (What is submitted?)

New section of regulation requiring protection of visibility in federal Class I areas in and near 

Washington. 

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

The intent of this section is to implement the federal visibility protection requirements found in 

40 CFR 52.27 and 52.28. 

18. Section 173-400-118 WAC, “Designation of Class I, II, and III areas.”

a) Description (What is submitted?)

New section of regulation that codifies 51.166(g) related to redesignation of areas.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section incorporates the process to redesignate an existing Class II area to Class I or Class 

III. The state rule section is the same as 40 CFR 51.21(g).

19. Section 173-400-131 WAC, “Issuance of emission reduction credits.”

a) Description (What is submitted?)

New section that implements a program to issue emission reduction credits useable for offsets 

required by the nonattainment New Source Review (NNSR) permitting program.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section has been revised since the last submittal to EPA for approval in the SIP. EPA 

disapproved that submittal and stated that it did not meet the requirements of its “Final 

Emissions Trading Policy Statement (51 FR 43814, December 4, 1986). In its disapproval 

statement, EPA noted that an emission reduction credit and trading program is not a required 

element of a nonattainment permitting program. However, for use of the emission reduction 

credits issued under this program, the credits would have to meet the criteria in 40 CFR 51.166 

for use as emission offsets and netting.
31

20. Section 173-400-136 WAC, “Use of emission reduction credits 

(ERC).”

a) Description (What is submitted?)

New section that implements the requirements for the use of emission reduction credits,

including their use as offsets required by the NNSR permitting program and other uses allowed 

in this section of rule. 

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section has been revised since last submittal to EPA for approval into the SIP. See analysis 

in 19.c) above for more information.

21. Section 173-400-151 WAC, “Retrofit requirements for visibility 

protection.”

a) Description 

Revised regulation language to implement the Best Available Retrofit Technology (BART)

program for existing stationary sources.

b) Action Ecology is requesting EPA to approve the revised section.

Replace the SIP-approved section with the revised version in the current state rule.

c) Analysis of Submittal

This section was modified in 2001 in response to the recommendations contained in the 1997 

Reasonably Attributable Visibility Impairment SIP review28. This review indicated the state rule 

contained a number of inconsistencies with the requirements of 40 CFR Part 51, sections 51.301 

– 306. The pre-2001 versions of WAC 173-400-151 utilized incorrect terms, most importantly 

the interpretation of the federal definition of “existing stationary facility.” In reviewing the 

language of WAC 173-400-151 in the SIP, the 1997 SIP Review Report29 noted a number of 

differences between the state rule and federal requirements. The report stated, “Further 

evaluation of why the exclusionary clause [in the definition of ‘existing stationary facility’] was 

omitted from the WAC needs to be made. If it is determined that it was an oversight or is no 

longer applicable, then the definition of “existing stationary facility” in WAC 173-400-030(26) 

should be revised to be consistent with the federal definition.” The exclusionary clause is the 

criteria limiting BART applicability to the 26 listed source types and categories and to those 

facilities that came into existence between 1962 and 1977.

 

28 Review of the Washington State Visibility Protection State Implementation Plan Final Report, April 1997, 

Publication No. 97-206

29 Ibid, see Section 7. Appendix C of this report contains a copy of the 1985 Washington State Visibility Protection 

Plan.
32

The subsequent review of the rule resulted in a decision to implement the federal rule criteria for 

what is an “existing stationary facility” for BART. This change better allowed Ecology to 

implement its BART responsibilities under the Regional Haze program. 

As a result of historical non-application of the rule as it appears in the SIP, the state rule change 

has had no substantive effect on the actual implementation of the BART process or defining 

which sources could be potentially subject to BART in Washington. State rules were changed in 

2001 to reflect the recommendation in the 1997 SIP Review Report. The revised Ecology rule 

now implements the federal definition of “existing stationary source.” This revision was used to 

develop the 2010 Regional Haze State Implementation Plan for Washington. 

22. Section 173-400-171 WAC, “Public notice.”

a) Description (What is submitted?)

Revised and restructured public involvement requirements from the requirements in the existing 

SIP-approved section.

b) Action (What would Ecology like EPA to do with the submittal?)

Replace the SIP-approved section with the revised version in the state rule, except for:

 the following words in 173-400-171(3)(b) “or any increase in emissions of a toxic air 

pollutant above the acceptable source impact level for that toxic air pollutant as regulated 

under chapter 173-460 WAC”.

 173-400-171(12). This is a new section related to Ecology only actions. Ecology does 

not propose to include it in the SIP.

c) Analysis of Submittal

The revisions establishes a procedure to inform the public of the receipt of Notice of 

Construction applications and criteria that would result in a public notice and public comment 

period on the permitting agency’s proposed action. The procedure to notify the public of 

applications received is based on the state of Idaho’s SIP-approved procedure. 

The content of WAC 173-400-171(12) mirrors and references requirements included in 40 C.F.R 

Part 51. These requirements list actions that Ecology is required to perform in relation to public 

comment periods and hearings for SIP actions and similar types of actions.

23. Section 173-400-175 WAC, “Public Information.”

a) Description (What is submitted?)

This new section was adopted in the state rule in 2005.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section in the SIP.
33

c) Analysis of Submittal

The new section states that all information, except information protected from public disclosure 

under any applicable law, is available for public inspection.

24. Section 173-400-200 WAC, “Creditable stack height and dispersion 

techniques.”

a) Description (What is submitted?)

Minor revision to existing SIP-approved section of regulation.

b) Action (What would Ecology like EPA to do with the submittal?)

Update this section in the SIP.

c) Analysis of Submittal

The minor revisions do not change the intent or application of this section, in practice. One 

change is to replace ‘open burning’ with ‘outdoor burning’; these terms are identical in the open 

burning regulation. The other is the addition of the word “permitting” to modify an outdated 

term referring to local air pollution control authorities. 

25. Section 173-400-560 WAC, “General order of approval.”

a) Description (What is submitted?)

Section 173-400-560 WAC provides the alternative minor NSR permit path.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP, except for:

 Part of 173-400-560(1)(f) that reads: “for 173-460 WAC”.

c) Analysis of Submittal

The Washington State Clean Air Act (Chapter 70.94 RCW) provides for the issuance of an order 

of approval for the establishment of a new source. General orders of approval are one of the 

tools Ecology uses to approve the establishment of new sources. These general orders fulfill all 

the requirements of an order of approval issued under the authority of WAC 173-400-110, 173-

400-111, 173-400-112, or 173-400-113.

Background

Section 560 of Chapter 173-400 WAC became effective on February 10, 2005. The concept of a 

general order of approval was developed and implemented with the overall goal of improved 

efficiency in the review and issuance of minor NSR permits. Ecology strives to improve its 

permitting program with the ultimate goal of issuing preconstruction approvals to its customers 

in the most cost-effective and time-efficient way while continuing to protect the air quality in 

Washington. 
34

Not every source category is eligible for a general order of approval. Ecology selected source 

categories where it had considerable experience in issuing approvals. The selected source 

categories are where BACT emission controls have not been changing or anticipated to change in 

the near future and the use of BACT emission controls will protect the NAAQS. The principle 

result has been to save time and money for the applicant and Ecology while protecting ambient 

air quality.

All general orders of approval are issued under the authority of WAC 173-400-560 and 173-400-

110. 

Elements of a General Order

The rule contains a number of criteria that must be met in order to issue a general order. The 

following is a list of the elements for issuance of a general order in WAC 173-400-560. Each 

general order shall consider:

1) Applicable emissions limitations and/or control requirements;

2) Best available control technology;

3) Appropriate operational restrictions, such as:

(i) Criteria related to the physical size of the unit(s) covered;

(ii) Criteria related to raw materials and fuels used;

(iii) Criteria related to allowed or prohibited locations; and

(iv) Other similar criteria determined by a permitting authority;

4) Monitoring, reporting and recordkeeping requirements to ensure compliance with the 

applicable emission limits and control requirements;

5) Appropriate initial and periodic emission testing requirements;

6) Compliance with chapter WAC 173-400-112 and 173-400-113 as applicable;

7) The application and approval process to obtain coverage under a general order of 

approval; and

8) Compliance with WAC 173-400-171 is required for a proposed new general order of 

approval or modification of an existing general order of approval.

Ecology intentionally limited the use of general orders in specific circumstances. General orders 

are not available to an emission unit or source if:

1) The requested emission unit or source is part of a new major stationary source or major 

modification subject to the requirements of WAC 173-400-700 through -750.

2) The requested emission unit or source is part of a new major stationary source or major 

modification subject to the requirements of WAC 173-400-800 through -860.

3) The requested emission unit or source triggers applicability of the operating permit 

program under Chapter 173-401 WAC or triggers a required modification of an existing 

operating permit.

4) Non-road engines, as defined in section 216 of the Federal Clean Air Act, are not 

included in general orders of approval.
35

The limitation on not using general orders for portions of a major NSR project is to assure that an 

applicant does not piecemeal a project into less than significant projects to avoid a major NSR 

permit. Similarly, the limitation on using a general order on the project that would require a 

source to obtain an Air Operating Permit (aka Title V) or triggers a mandatory modification of an 

air operating permit is because these are major actions that trigger numerous additional 

requirements found in WAC 173-401, Air Operating Permits. 

Current General Orders of Approval

Ecology has issued a number of general orders of approval since 2005. The following is the list 

of general orders of approval that have been issued and are available to sources proposing to 

operate in counties regulated by Ecology. 

 Dairy anaerobic digesters

 Concrete batch plants

 Gas-powered emergency electric generators

 Rock crushers

 Small water heaters and steam generating boilers

 Auto body shops

 Asphalt plants

The General Order for small water heaters and steam generating boilers has been modified 

several times since initial issuance to reflect changes in scope and the other emission 

requirements these units are required to meet.

General orders of approval issued under the authority of WAC 173-400-560 also meet all the 

requirements of an order of approval issued under the authority of WAC 173-400-110. 

26. Section 173-400-700 WAC, “Review of major stationary sources of air 

pollution.”

a) Description (What is submitted?)

New rule section addressing the PSD program requirements in Washington.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This new section provides an overview of the PSD program requirements and establishes the 

relationship of the requirements in WAC 173-400-710 through -750 to local authority PSD 

delegations or SIP-approved PSD programs and the EFSEC major source permitting

requirements. 
36

27. Section 173-400-710 WAC, “Definitions”

a) Description (What is submitted?)

New rule section addressing the Prevention of Significant Deterioration program requirements in 

Washington.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section establishes the priority of potentially conflicting definitions between the PSD and 

state NOC program requirements. This section establishes that for purposes of the PSD program, 

the definition in 40 CFR 52.21, as adopted by reference in WAC 173-400-720, is to be used.

28. Section 173-400-720 WAC, “Prevention of signification deterioration 

(PSD).”

a) Description (What is submitted?)

New rule section addressing the PSD program requirements in Washington.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section in the SIP, except for:

 WAC 173-400-720(4)(a)(i) through (iv). 

 2 specific sub-sections of 40 CFR 52.21 adopted by reference in 40 CFR 52.21, in WAC 

173-400-720(4)(a)(vi). The specific subsections we request that EPA not approve are

52.21(i)(5)(i) defining a significant monitoring concentration for PM2.5 and in 

52.21(k)(2) establishing a PM2.5 significant impact level.

c) Analysis of Submittal

This section adopts by reference 40 CFR 52.21, with listed exceptions, as the PSD permitting 

program in Washington. It also substitutes some state regulatory requirements for requirements 

in § 52.21 implementing the 2003 new source reform package. These are the basic program 

requirements that have been the basis for PSD delegations from EPA for the past 10 years.

Ecology intends to amend WAC 173-400-720(4)(a)(i)-(iv) in the near future to clarify the 

meaning of the language, and will submit the revised provisions for inclusion in the SIP once 

they have been finalized. Ecology notes that other provisions proposed for inclusion in the SIP 

ensure that each of the requirements listed in WAC 173-400-720(4)(a)(i) through (iv) must be 

addressed in the process to issue a PSD permit, regardless of whether the requirements are listed 

in WAC 173-400-720(4)(a)(i) through (iv). For more information, please see Attachment B to 

Appendix F titled “Ecology’s letter to EPA from November 1, 2013”.
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The two subsections, § 52.21(5)(k) and § 52.21(i)(5(i), included in the version of 40 CFR 52.21 

which Ecology has adopted by reference have been vacated or remanded by the courts to EPA 

for revision. As such, they are not part of an approvable PSD program. More details are below:

Significant Impact Leves (SILs) / Significant Monitoring Concentration (SMCs)

On January 22, 2013, the U.S. Court of Appeals for the District of Columbia, in Sierra Club v. 

EPA, 705 F.3d 458, vacated and remanded the provisions at 40 CFR 51.166(k)(2) and 

52.21(k)(2) (concerning implementation of the PM2.5 SILs) and vacated the provisions at 40 CFR

51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c) (adding the PM2.5 SMC) that were promulgated as part of 

the 2010 PM2.5 PSD Rule, "Prevention of Significant Deterioration (PSD) for Particulate Matter 

less than 2.5 Micrometers (PM2.5) -Increments, Significant Impact Levels (SILs) and Significant 

Monitoring Concentration (SMC)," 75 FR 64864 (October 20, 2010). 

Consistent with the court decision, Ecology is not submitting the PM2.5 SILs and SMC provisions 

adopted by reference in WA’s regulations at WAC 173-400-720(4)(a)(vi) (specifically, the 

adoption by reference of 40 CFR 52.21(k)(2) and 40 CFR 52.21 (i)(5)(i)(c) in WAC 173-400-

720(4)(a)(vi)) and asks that the EPA approve all other aspects of WAC 173-400-720. 

The PM2.5 SILs and SMC provisions adopted by reference at WAC 173-400-720 still appear in 

the state regulations until amended by future action and Ecology plans to do so at the first 

opportunity.

In light of the court decision and until Ecology has revised its state regulations, Ecology

confirms that, consistent with authorities in State law, it will not apply either the PM2.5 SILs 

provisions at 52.21(k)(2) or the PM2.5 SMC provisions at 52.21 (i)(5)(i)(c) (as incorporated by 

reference by Ecology at WAC 173-400-720(4)(a)(vi)) to pending or future PSD permit actions. 

Specifically, with respect to SILs, consistent with the Court’s decision in Sierra Club v. EPA and 

statements by EPA in the preamble to the 2010 final rule, Ecology does not interpret 40 CFR 

section 52.21(k)(2), as incorporated by reference in Ecology’s rules to preclude Ecology from 

exercising discretion to determine when it may be appropriate to conclude that an impact below 

the PM2.5 SIL values in section 52.21(k)(2) will cause or contribute to an air quality problem and 

to seek remedial action from the proposed new source or modification. Such discretion is 

necessary to ensure a PSD project meets the requirement of the Clean Air Act and that a PSD 

project not cause or contribute to a violation of any NAAQS or any applicable increment. Based 

on this interpretation, Ecology affirms that it will not read section 52.21(k)(2), as incorporated by 

reference in its rules as an absolute “safe harbor”, but will exercise discretion to determine 

whether a particular application of the PM2.5 SIL values is appropriate when a substantial portion 

of the PM2.5 NAAQS or increment is known to be consumed.

Ecology retains the discretion to require additional information from a permit applicant as 

needed to assure that the source will not cause or contribute to a violation of any NAAQS or 

applicable increment pursuant to section 52.21(k)(1) and will consider the approach outlined in 
38

the Draft Guidance for PM2.5 Permit Modeling released by the agency for public comment and 

any final guidance regarding the appropriate application of the PM2.5 SIL going forward. With 

respect to SMC’s, 40 CFR 52.21(i)(5)(i)(c) provides Ecology with the discretion to determine 

whether it is appropriate to apply the SMC for PM2.5 to exempt a permit applicant from the 

requirement to compile and submit preconstruction ambient monitoring data for PM2.5 as part of 

a complete PSD application. Consistent with the Court’s decision in Sierra Club v. EPA 

vacating the PM2.5 SMC, Ecology affirms that it will not exercise its discretionary authority to 

use the PM2.5 SMC in order to exempt PSD permit applicants from the requirement in Clean Air 

Act section 165(e)(2) that ambient monitoring data for PM2.5 be included in applications subject 

to the PSD program for PM2.5. Additionally, that Ecology will require all applicants requesting 

a PSD permit, including those having already applied for but have not yet received the permit, to 

submit ambient PM2.5 monitoring data in accordance with the Clean Air Act requirements 

whenever proposed increases of direct PM2.5 emissions or any emissions of a PM2.5 precursor 

equal or exceed a significant amount. 

Biogenic CO2 Deferral 

On July 12, 2013, the U.S. Court of Appeals for the District of Columbia, in the Center for 

Biological Diversity v. EPA, No. 11-1101 (D.C. Cir. July 12, 2013), vacated the Biogenic CO2

Deferral Rule (76 Fed. Reg. 43490 (July 20, 2011). At the time this notice for public comment 

was published, the court had not issued the mandate in that case, and the deadline for parties to 

seek rehearing or appeal has not arrived. 

If the mandate is issued at some point in the future, and consistent with the court decision, 

Ecology intends to inform EPA that the submittal does not include the Biogenic CO2 Deferral.

29. Section 173-400-730 WAC, “Prevention of significant deterioration 

application processing procedures.”

a) Description (What is submitted?)

New rule section addressing the processing of applications for permits under the Prevention of 

Significant Deterioration program requirements in Washington.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section establishes the procedures for submittal of applications and the processing of those 

applications for PSD permits. Procedures are based on the requirements in 40 CFR 51.166 and 

40 CFR Part 124. 
39

30. Section 173-400-740 WAC, “PSD permitting public involvement 

requirements.”

a) Description (What is submitted?)

New rule section addressing the public involvement requirements for PSD permitting decisions.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section establishes the procedures for submittal of applications and the processing of those 

applications for PSD permits. Procedures are based on the requirements in 40 CFR 51.166(q) 

and 40 CFR Part 124. 

31. Section 173-400-750 WAC, “Revisions to PSD permits.”

a) Description (What is submitted?)

New rule section addressing how to revise requirements in PSD permits after issuance.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP, except for the reference in subsection (2), second sentence 

that says: “The fee schedule found in chapter 173-455 WAC also applies.”

c) Analysis of Submittal

This section establishes when a permit holder may request revisions to an existing PSD permit. 

Establishes criteria to determine if the requested revision is a minor revision not requiring public 

involvement or is more involved and a public comment period is involved. Also contains criteria 

used to determine the amount of permit processing fee that is to be charged. Subsection (2) has a 

reference to a WAC chapter that is not approved into the SIP, thus Ecology does not propose to 

include this reference in the SIP.

32. Section 173-400-800 WAC, “Major stationary source and major 

modification in a nonattainment area.”

a) Description (What is submitted?)

New rule section addressing nonattainment new source review requirements in Washington.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section outlines the nonattainment area new source review program requirements and 

establishes the relationship of the requirements in WAC 173-400- 810 through 850 to a local 

authority’s SIP-approved nonattainment area NSR programs.
40

33. Section 173-400-810 WAC, “Major stationary source and major 

modification definitions.”

a) Description (What is submitted?)

New section that contains the definitions used in the nonattainment new source review program.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section mirrors the definitions contained in 40 CFR 51.165 and reorganizes them 

alphabetically. This section also establishes priority for the definitions in this section to be used 

for the NNSR program, even when a term may be defined differently elsewhere, such as in WAC 

173-400-030 or -720.

34. Section 173-400-820 WAC, “Determining if a new stationary source of 

modification to a stationary source is subject to these requirements.”

a) Description (What is submitted?)

New section that establishes the procedures to determine if a proposed project in a nonattainment 

area is subject to the nonattainment area permitting requirements.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section mirrors the emission calculations found in 40 CFR 51.165 to determine if a project 

in a nonattainment area is subject to nonattainment area NSR requirements due to an increase in 

its emissions. The section also includes an identical version of the EPA ‘reasonable possibility’

test included in the PSD program.

35. Section 173-400-830 WAC, “Permitting requirements.”

a) Description (What is submitted?)

New section establishing the permitting requirements that must be met for any project requiring 

nonattainment are NSR permitting.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section copies portions of previous requirements in WAC 173-400-112, as approved into 

the SIP, plus additional requirements added to 40 CFR 51.165 after 1993. 
41

36. Section 173-400-840 WAC, “Emission offset requirements.”

a) Description (What is submitted?)

New section establishing and making enforceable requirements to offset emissions.

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section makes enforceable requirements to offset emissions and establishes the minimum 

offset requirements. This section establishes a relationship on the use of emission reduction

credits issued under Chapter 173-400 WAC and emission reductions for emission reduction 

credits that have not been issued to be useable as emission offsets.

37. Section 173-400-850 WAC, “Actual emissions plantwide applicability 

limitation.”

a) Description (What is submitted?)

New section establishing the opportunity for a source to obtain a plant-wide applicability limit 

for the nonattainment area pollutant (and precursors).

b) Action (What would Ecology like EPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section adopts by reference the plant-wide applicability limit process and requirements of 

40 CFR Part 51, Appendix S.

38. Section 173-400-860 WAC, “Public involvement procedures.”

a) Description (What is submitted?)

New section describing the public involvement process for nonattainment area NSR.

b) Action (What would Ecology likeEPA to do with the submittal?)

Approve the new section into the SIP.

c) Analysis of Submittal

This section directs that the public involvement procedures to be followed are in WAC 173-400-

171.
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IV. Appendices

Appendices are in separate documents within the SIP submittal package. Appendix E is a large 

spreadsheet that is designed to be viewed electronically; it is included in the enclosed CD.

Appendix A: Overview Table

Appendix B: Strikeout SIP Approved Rule Language

Appendix C: Environmental Checklist for “Amendments to Chapter 174-400 WAC, 

General Regulation for Air Pollution Sources”

Appendix D: Determination of Applicability of MTCA Exemption to Air Quality 

Permitting Programs

Appendix E: Comparison of emission units and rates exempt from permitting in 

Washington, some other states, and the EPA Tribal NSR rule

Appendix F: Response to Comments

Appendix G: Public Involvement

1. Affidavit of Publication in The Daily Journal of Commerce

2. SIP Revision Public Notice

3. Ecology’s News Release

4. Ecology’s Public Involvement Calendar

5. Notice in Ecology’s Toxic Cleanup Program Site Register

6. Hearing Summary Memorandum

Appendix H: SIP Adoption Order