ENCLOSURE 1

COMMONWEALTH OF VIRGINIA

STATE AIR POLLUTION CONTROL BOARD

REGULATIONS FOR THE CONTROL AND ABATEMENT OF AIR POLLUTION

PROVISIONS AFFECTED

REVISION F10

CONCERNING

GENERAL CONFORMITY

(9VAC5 CHAPTER 160)

Adoption Date: December 17, 2010

Effective Date: March 2, 2011

The following table lists the specific provisions of the attached regulations that will be 

used to implement the State Implementation Plan (SIP). A copy of the actual regulation 

submitted for approval and incorporation by reference into the Virginia SIP is included 

in Enclosure 2.

CHAPTER 160 GENERAL CONFORMITY

PART I GENERAL DEFINITIONS

9VAC5-160-10 General 

9VAC5-160-20 Terms defined

Added - applicability analysis, confidential business information 

(CBI), conformity determination, conformity evaluation, continuing 

program responsibility, continuous program to implement, 

emissions inventory, mitigation measure, restricted information, 

take or start the federal action.

Modified - applicable implementation plan, areawide air quality 

modeling analysis, direct emissions, emissions budgets, EPA, 

federal Clean Air Act, indirect emissions, local air quality modeling 

analysis, maintenance area, metropolitan planning organization, new 

source review (NSR) program, precursors of a criteria pollutant, 

reasonably foreseeable emissions.

Deleted - emissions that a federal agency has a continuing 

program responsibility for, regionally significant action.

PART II GENERAL PROVISIONS

9VAC5-160-30 Applicability (modified)

9VAC5-160-40 Authority of board and department

9VAC5-160-50 Repealed
9VAC5-160-60 Repealed

9VAC5-160-70 Repealed

9VAC5-160-80 Relationship of state regulations to federal regulations

9VAC5-160-90 Repealed

PART III CRITERIA AND PROCEDURES FOR MAKING CONFORMITY 

DETERMINATIONS

9VAC5-160-110 General (modified)

9VAC5-160-120 Federal agency conformity responsibility (modified)

9VAC5-160-130 Reporting requirements (modified)

9VAC5-160-140 Public participation (modified)

9VAC5-160-150 Reevaluation of conformity (modified)

9VAC5-160-160 Criteria for determining conformity of general federal actions

(modified)

9VAC5-160-170 Procedures for conformity determinations (modified)

9VAC5-160-180 Mitigation of air quality impacts (modified)

9VAC5-160-181 Conformity evaluation for federal installations with facility-wide 

emission budgets (added)

9VAC5-160-182 Emissions beyond the time period covered by the applicable 

implementation plan (added)

9VAC5-160-183 Timing of offsets and mitigation measures (added)

9VAC5-160-184 Inter-precursor mitigation measures and offsets (added)

9VAC5-160-185 Early emission reduction credit programs at federal facilities and 

installation subject to federal oversight (added)

9VAC5-160-190 Savings provision

9VAC5-160-200 Repealed (modified)

TEMPLATES\SIP-REG\REG01

SIP\NONATTN PLANS\2011\F10-SIP-1.DOC
COMMONWEALTH OF VIRGINIA PAGE 1 of 35

STATE AIR POLLUTION CONTROL BOARD

REGULATION FOR GENERAL CONFORMITY (9VAC5-160)

9VAC5 CHAPTER 160.

REGULATION FOR GENERAL CONFORMITY.

PART I.

GENERAL DEFINITIONS.

9VAC5-160-10. General.

A. For the purpose of this regulation and subsequent amendments or any orders 

issued by the board, the words or terms shall have the meanings given them in 9VAC5-

160-20.

B. Unless specifically defined in the Virginia Air Pollution Control Law or in this 

regulation, terms used shall have the meanings given them by the federal Clean Air Act, 

other U.S. Environmental Protection Agency (EPA) regulations, 9VAC5-170-20 

(definitions, Regulation for General Administration), or commonly ascribed to them by 

recognized authorities, in that order of priority.

9VAC5-160-20. Terms defined.

"Administrator" means the administrator of EPA or an authorized 

representative.

"Affected federal land manager" means the federal agency or the federal 

official charged with direct responsibility for management of an area designated as class I 

under the federal Clean Air Act, and located within 100 kilometers of the proposed federal 

action.

"Ambient air" means that portion of the atmosphere, external to buildings, to 

which the general public has access.

"Applicability analysis" means the process of determining if the federal 

action shall be supported by a conformity determination.

"Applicable implementation plan" means the portion or portions of the state 

implementation plan, or the most recent revision thereof, which has been approved under 

§ 110(k) of the federal Clean Air Act, or a federal implementation plan promulgated under 

§ 110(c) of the federal Clean Air Act, or promulgated or approved pursuant to regulations 

promulgated under § 301(d) of the federal Clean Air Act and which implements the 

relevant requirements of the federal Clean Air Act.

"Areawide air quality modeling analysis" means an assessment on a scale 

that includes the entire nonattainment area or maintenance area which uses using an air 

quality dispersion model or photochemical grid model to determine the effects of 
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emissions on air quality, for example, an assessment using EPA's community multiscale air quality (CMAQ) modeling system.

"Board" means the State Air Pollution Control Board or its designated 

representative.

"Cause or contribute to a new violation" means a federal action that:

1. Causes a new violation of a national ambient air quality standard 

at a location in a nonattainment or maintenance area which would otherwise not be in 

violation of the standard during the future period in question if the federal action were not 

taken; or

2. Contributes, in conjunction with other reasonably foreseeable 

actions, to a new violation of a national ambient air quality standard at a location in a 

nonattainment or maintenance area in a manner that would increase the frequency or 

severity of the new violation.

"Caused by" means, as used in the terms "direct emissions" and "indirect 

emissions," emissions that would not otherwise occur in the absence of the federal action.

"Confidential business information" or "CBI" means information that has 

been determined by a federal agency, in accordance with its applicable regulations, to 

be a trade secret, or commercial or financial information obtained from a person and 

privileged or confidential and is exempt from required disclosure under the Freedom of 

Information Act (5 USC 552(b)(4)).

"Conformity determination" means the evaluation (made after an 

applicability analysis is completed) that a federal action conforms to the applicable 

implementation plan and meets the requirements of this regulation.

"Conformity evaluation" means the entire process from the applicability 

analysis through the conformity determination that is used to demonstrate that the 

federal action conforms to the requirements of this regulation.

"Consultation" means that one party confers with another identified party, 

provides all information to that party needed for meaningful input, and, prior to taking any 

action, considers the views of that party and responds to those views in a timely, 

substantive, written manner prior to any final decision on the action. The views and written

response shall be made part of the record of any decision or action.

"Continuing program responsibility" means a federal agency has 

responsibility for emissions caused by (i) actions it takes itself; or (ii) actions of nonfederal entities that the federal agency, in exercising its normal programs and 
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REGULATION FOR GENERAL CONFORMITY (9VAC5-160)

authorities, approves, funds, licenses or permits, provided the agency can impose 

conditions on any portion of the action that could affect the emissions.

"Continuous program to implement" means that the federal agency has 

started the action identified in the plan and does not stop the actions for more than an 

18-month period, unless it can demonstrate that such a stoppage was included in the 

original plan.

"Control" means the ability to regulate the emissions from the action. The 

ability to regulate may be demonstrated directly, such as through the use of emission 

control equipment, or indirectly, such as through the implementation of regulations or 

conditions on the nature of the activity that may be established in permits or approvals or 

by the design of the action. An example of control includes the ability of a federal agency 

to control the level of vehicle emissions by controlling the size of a parking facility and 

setting requirements for employee trip reductions.

"Criteria pollutant" means any pollutant for which there is established a 

national ambient air quality standard in 40 CFR Part 50.

"Department" means any employee or other representative of the Virginia 

Department of Environmental Quality, as designated by the director.

"Direct emissions" means those emissions of a criteria pollutant or its 

precursors that are caused or initiated by the federal action and originate in a 

nonattainment or maintenance area and occur at the same time and place as the action

and are reasonably foreseeable.

"Director" means the director of the Virginia Department of Environmental 

Quality.

"Emergency" means, in the context of 9VAC5-160-30, a situation where 

extremely quick action on the part of federal agencies involved is needed and where the 

timing of the federal activities makes it impractical to meet the requirements of this 

regulation, such as natural disasters like hurricanes or earthquakes, civil disturbances 

such as terrorist acts, and military mobilizations.

"Emergency" means, in the context of 9VAC5-160-40, a situation that 

immediately and unreasonably affects, or has the potential to immediately and 

unreasonably affect, public health, safety or welfare; the health of animal or plant life; or 

property, whether used for recreational, commercial, industrial, agricultural or other 

reasonable use.

"Emissions budgets" are means those portions of the total allowable 

emissions defined in the applicable implementation plan for a certain date for the purpose 
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of meeting reasonable further progress milestones or attainment or maintenance 

demonstrations, for any criteria pollutant or its precursors, specifically allocated by the 

applicable implementation plan to mobile sources, to any stationary source or class of 

stationary sources, to any federal action or any class of action, to any class of area 

sources, or to any subcategory of the emissions inventory. The allocation system shall be 

specific enough to assure meeting the criteria of § 176(c)(1)(B) of the federal Clean Air 

Act. An emissions budget may be expressed in terms of an annual period, a daily period, 

or other period established in the applicable implementation plan.

"Emissions inventory" means a listing of information on the location, type 

of source, type and quantity of pollutant emitted as well as other parameters of the 

emissions.

"Emissions offsets" means, for the purposes of 9VAC5-160-160, emissions 

reductions which are quantifiable, consistent with the applicable implementation plan 

attainment and reasonable future progress demonstrations, surplus to reductions required 

by, and credited to, other applicable implementation plan provisions, enforceable under 

both state and federal law, and permanent within the timeframe specified by that 

program. Emissions reductions intended to be achieved as emissions offsets under this 

regulation shall be monitored and enforced in a manner equivalent to that under the new 

source review program.

"Emissions that a federal agency has a continuing program responsibility 

for" means emissions that are specifically caused by an agency carrying out its 

authorities, and does not include emissions that occur due to subsequent activities, 

unless the activities are required by the federal agency. Where an agency, in performing 

its normal program responsibilities, takes actions itself or imposes conditions that result in 

air pollutant emissions by a non-federal entity taking subsequent actions, the emissions 

are covered by the meaning of a continuing program responsibility.

"EPA" means the United States U.S. Environmental Protection Agency.

"Facility" means something that is built, installed, or established to serve a 

particular purpose; includes, but is not limited to, buildings, installations, public works, 

businesses, commercial and industrial plants, shops and stores, heating and power 

plants, apparatus, processes, operations, structures, and equipment of all types.

"Federal action" means any activity engaged in by a federal agency, or any 

activity that a federal agency supports in any way, provides financial assistance for, 

licenses, permits, or approves, other than activities related to transportation plans, 

programs, and projects developed, funded, or approved under title 23 USC or the Federal 

Transit Act (49 USC 1601 et seq.). Where the federal action is a permit, license, or other 

approval for some aspect of a non-federal undertaking, the relevant action is the part, 

portion, or phase that the non-federal undertaking that requires the federal permit, 
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license, or approval.

"Federal agency" means a department, agency, or instrumentality of the 

federal government.

"Federal Clean Air Act" means 42 USC 7401 et seq Chapter 85 (§ 7401 et 

seq.) of Title 42 of the United States Code.

"Increase the frequency or severity of any existing violation of any standard 

in any area" means to cause a nonattainment area to exceed a standard more often, or to 

cause a violation at a greater concentration than previously existed or would otherwise 

exist during the future period in question, if the project were not implemented.

"Indirect emissions" means those emissions of a criteria pollutant or its 

precursors that:

1. Are caused or initiated by the federal action and originate in the 

same nonattainment or maintenance area, but may occur later in time, or may be farther 

removed in distance from the action itself but are still reasonably foreseeable; and at a 

different time or place as the action;

2. The federal agency can practicably control and will maintain 

control over due to a continuing program responsibility of the federal agency, including, 

but not limited to:

a. Traffic on or to, or stimulated or accommodated by, a 

proposed facility which is related to increases or other changes in the scale or timing of 

operations of the facility;

b. Emissions related to the activities of employees of 

contractors or federal employees;

c. Emissions related to employee commutation and similar 

programs to increase average vehicle occupancy imposed on all employers of a certain 

size in the locality; and

d. Emissions related to the activities of contractors or 

leaseholders that may be addressed by provisions that are usual and customary for 

contracts or leases or within the scope of contractual protection of the interests of the 

United States. That are reasonably foreseeable;

3. That the agency can practically control; and

4. For which the agency has a continuing program responsibility.
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For the purposes of this definition, even if a federal licensing, rulemaking or other 

approving action is a required initial step for a subsequent activity that causes 

emissions, such initial steps do not mean that a federal agency can practically control 

any resulting emissions.

"Lead Planning Organization" means the organization certified by the state 

as being responsible for the preparation of control strategy implementation plan revisions 

for nonattainment areas under § 174 of the federal Clean Air Act. The organization 

includes elected officials of local governments in the affected nonattainment area, and 

representatives of the department, the Virginia Department of Transportation, the 

metropolitan planning organizations for the affected area, and other agencies and 

organizations that have responsibilities for developing, submitting or implementing any of 

the plan revisions. It is the forum for cooperative air quality planning decision-making.

"Local air quality modeling analysis" means assessment of localized 

impacts on a scale smaller than the entire nonattainment or maintenance area, including, 

for example, congested roadway intersections and highways or transit terminals roadways

on a federal facility, which that uses an air quality dispersion model (e.g., Industrial 

Source Complex Model or Emission and Dispersion Model System) to determine the 

effects of emissions on air quality.

"Maintenance area" means any geographic region of the United States 

previously an area that was designated as a nonattainment area and subsequently has 

been redesignated in 40 CFR Part 81 to attainment subject to the requirement to develop 

a maintenance plan , meeting the provisions of § 107(d)(3)(E) of the federal Clean Air 

Act and has a maintenance plan approved under § 175A of the federal Clean Air Act.

"Maintenance plan" means a revision to the applicable implementation plan, 

meeting the requirements of § 175A of the federal Clean Air Act.

"Metropolitan planning organization" means the policy board of an

organization designated as being responsible, together with the Commonwealth of 

Virginia, for conducting the continuing, cooperative, and comprehensive planning process 

under created as a result of the designation process in 23 USC 134(d) and 49 USC 1607.

"Milestone" means as defined in §§ 182(g) and 189(c)(1) of the federal 

Clean Air Act. A milestone consists of an emissions level and the date on which it is 

required to be achieved.

"Mitigation measure" means any method of reducing emissions of the 

pollutant or its precursor taken at the location of the federal action and used to reduce 

the impact of the emissions of that pollutant caused by the action.
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STATE AIR POLLUTION CONTROL BOARD

REGULATION FOR GENERAL CONFORMITY (9VAC5-160)

"National ambient air quality standards" means those standards established 

pursuant to § 109 of the federal Clean Air Act.

"NEPA" means the National Environmental Policy Act of 1969 as amended 

(42 USC 4321 et seq.)

"New source review (NSR) program" means a program for the 

preconstruction review and permitting of new stationary sources or expansions to existing 

ones in accordance with regulations promulgated to implement the requirements of §§ 

110 (a)(2)(C), 165 (relating to permits in prevention of significant deterioration areas) and 

173 (relating to permits in nonattainment areas) of the federal Clean Air Act a 

preconstruction review and permit program (i) for regulated air pollutants from new 

stationary sources or projects (physical changes or changes in the method of 

operation), (ii) established to implement the requirements of §§ 110 (a)(2)(C), 112 

(relating to permits for hazardous air pollutants), 165 (relating to permits in prevention of 

significant deterioration areas), and 173 (relating to permits in nonattainment areas) of 

the federal Clean Air Act and associated regulations, and (iii) Article 7 (9VAC5-80-1400 

et seq.), Article 8 (9VAC5-80-1605 et seq.) and Article 9 (9VAC5-80-2000 et seq.) of 

Part II of 9VAC5-80 (Permits for Stationary Sources) of the Regulations for the Control 

and Abatement of Air Pollution.

"Nonattainment area" means any geographic region of the United States 

which has been designated as nonattainment under § 107 of the federal Clean Air Act for 

any pollutant for which a national ambient air quality standard exists.

"PM10" means particulate matter with an aerodynamic diameter less than or 

equal to a nominal 10 micrometers as measured by the applicable reference method or 

an equivalent method.

"Person" means an individual, corporation, partnership, association, a 

governmental body, a municipal corporation, or any other legal entity.

"Precursors of a criteria pollutant" means:

1. For ozone,

a. Nitrogen oxides, unless an area is exempted from nitrogen 

oxides requirements under § 182(f) of the federal Clean Air Act, and 

b. Volatile organic compounds; and .

2. For PM10, those pollutants described in the PM10 nonattainment 

area applicable implementation plan as significant contributors to the particulate matter

PM10 levels.
COMMONWEALTH OF VIRGINIA PAGE 8 of 35

STATE AIR POLLUTION CONTROL BOARD

REGULATION FOR GENERAL CONFORMITY (9VAC5-160)

3. For PM2.5, (i) sulfur dioxide in all PM2.5 nonattainment and 

maintenance areas, (ii) nitrogen oxides in all PM2.5 nonattainment and maintenance 

areas unless both the department and EPA determine that it is not a significant 

precursor, and (iii) volatile organic compounds and ammonia only in PM2.5

nonattainment or maintenance areas where either the department or EPA determines 

that they are significant precursors.

"Reasonably foreseeable emissions" are means projected future direct and

indirect emissions that are identified at the time the conformity determination is made; the 

location of the such emissions is known to the extent adequate to determine the impact of 

the emissions; and the emissions are quantifiable, as described and documented by the 

federal agency based on its own information and after reviewing any information 

presented to the federal agency.

"Regional water or wastewater projects" means construction, operation, and 

maintenance of water or wastewater conveyances, water or wastewater treatment 

facilities, and water storage reservoirs which affect a large portion of a nonattainment or 

maintenance area.

"Regionally significant action" means a federal action for which the direct 

and indirect emissions of any pollutant represent 10% or more of a nonattainment or 

maintenance area's emissions inventory for that pollutant.

"Restricted information" means information that is privileged or that is 

otherwise protected from disclosure pursuant to applicable statutes, Executive Orders, 

or regulations. Such information includes, but is not limited to, classified national 

security information, protected critical infrastructure information, sensitive security 

information, and proprietary business information.

"Source" means any one or combination of the following: buildings, 

structures, facilities, installations, articles, machines, equipment, landcraft, watercraft, 

aircraft, or other contrivances which contribute, or may contribute, either directly or 

indirectly to air pollution. Any activity by any person that contributes, or may contribute, 

either directly or indirectly to air pollution, including, but not limited to, open burning, 

generation of fugitive dust or emissions, and cleaning with abrasives or chemicals.

"Take or start the federal action" means the date that the federal agency 

signs or approves the permit, license, grant or contract or otherwise physically begins 

the federal action that requires a conformity evaluation under this chapter.

"Total of direct and indirect emissions" means the sum of direct and indirect 

emissions increases and decreases caused by the federal action, that is, the "net" 

emissions considering all direct and indirect emissions. Any emissions decreases used to 
COMMONWEALTH OF VIRGINIA PAGE 9 of 35

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REGULATION FOR GENERAL CONFORMITY (9VAC5-160)

reduce the total shall have already occurred by the time the corresponding increases 

occur or shall be enforceable under state and federal law. The portion of emissions which 

are exempt or presumed to conform under 9VAC5-160-30 are not included in the "total of 

direct and indirect emissions," except as provided in 9VAC5-160-30 M. The "total of direct 

and indirect emissions" includes emissions of criteria pollutants and emissions of 

precursors of criteria pollutants. Segmentation of projects for conformity analyses when 

emissions are reasonably foreseeable is prohibited.

"Virginia Air Pollution Control Law" means Chapter 13 (§ 10.1-1300 et seq.) 

of Title 10.1 of the Code of Virginia.

"Welfare" means that language referring to effects on welfare includes, but 

is not limited to, effects on soils, water, crops, vegetation, human-made materials, 

animals, wildlife, weather, visibility and climate, damage to and deterioration of property, 

and hazards to transportation, as well as effects on economic values and on personal 

comfort and well being.

PART II.

GENERAL PROVISIONS.

9VAC5-160-30. Applicability.

A. The provisions of this regulation shall apply in all nonattainment and 

maintenance areas for criteria pollutants for which the area is designated nonattainment 

or has a maintenance plan. Conformity requirements for newly designated 

nonattainment areas are not applicable until 1 year after the effective date of the final 

nonattainment designation for each national ambient air quality standard and pollutant 

in accordance with § 176(c)(6) of the federal Clean Air Act.

B. The provisions of this regulation apply with respect to emissions of the following 

criteria pollutants: ozone, carbon monoxide, nitrogen dioxide, and particles with an 

aerodynamic diameter less than or equal to a nominal 10 micrometers (PM10), and 

particles with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers

(PM2.5).

C. The provisions of this regulation apply with respect to emissions of the following 

precursor pollutants:

1. For ozone:

a. Nitrogen oxides, unless an area is exempted from nitrogen oxides 

requirements under § 182(f) of the federal Clean Air Act, and 

b. Volatile organic compounds.
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2. For PM10, those pollutants described in the PM10 nonattainment area 

applicable implementation plan as significant contributors to the particulate matter PM10

levels.

3. For PM2.5, (i) sulfur dioxide in all PM2.5 nonattainment and maintenance 

areas, (ii) nitrogen oxides in all PM2.5 nonattainment and maintenance areas unless 

both the department and EPA determine that it is not a significant precursor, and (iii)

volatile organic compounds and ammonia only in PM2.5 nonattainment or maintenance 

areas where either the department or EPA determines that they are significant 

precursors.

D. Conformity determinations for federal actions related to transportation plans,

programs, and projects developed, funded, or approved under title 23 USC or the Federal 

Transit Act (49 USC 1601 et seq.) shall meet the procedures and criteria of the

Regulation for Transportation Conformity (9VAC5 Chapter 150) 9VAC5-151 (Regulation 

for Transportation Conformity), in lieu of the procedures set forth in this regulation.

E. For federal actions not covered by subsection D of this section, a conformity 

determination is required for each criteria pollutant or precursor where the total of direct 

and indirect emissions of the criteria pollutant or precursor in a nonattainment or 

maintenance area caused by a federal action would equal or exceed any of the rates in 

subdivision 1 or 2 of this subsection.

1. For the purposes of this subsection, the following rates apply in nonattainment 

areas:

Tons per year

Ozone (VOCs or NOX):

Serious nonattainment areas 50

Severe nonattainment areas 25

Extreme nonattainment areas 10

Other ozone nonattainment areas 

outside an ozone transport region

100

Marginal and moderate Other ozone

nonattainment areas inside an ozone 

transport region:

VOC 50

NOX 100

Carbon monoxide, all nonattainment areas 100

Sulfur dioxide or nitrogen dioxide, all 100
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nonattainment areas

PM10:

Moderate nonattainment areas 100

Serious nonattainment areas 70

PM2.5:

Direct emissions 100

Sulfur dioxide 100

Nitrogen oxides (unless determined 

not to be significant precursors)

100

Volatile organic compounds or 

ammonia (if determined to be 

significant precursors)

100

Lead, all nonattainment areas 25

2. For the purposes of this subsection, the following rates apply in maintenance 

areas:

Tons per year

Ozone (NOx), sulfur dioxide, or nitrogen 

dioxide, all maintenance areas

100

Ozone (VOCs):

Maintenance areas inside an ozone 

transport region

50

Maintenance areas outside an 

ozone transport region

100

Carbon monoxide, all maintenance areas 100

PM10, all maintenance area areas 100

PM2.5:

Direct emissions 100

Sulfur dioxide 100

Nitrogen oxides (unless determined 

not to be a significant precursor)

100

Volatile organic compounds or 

ammonia (if determined to be 

significant precursors)

100

Lead, all maintenance areas 25
COMMONWEALTH OF VIRGINIA PAGE 12 of 35

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F. The requirements of this section shall not apply to the following federal actions:

1. Actions where the total of direct and indirect emissions are below the 

emissions levels specified in subsection E of this section.

2. The following actions which would result in no emissions increase or an 

increase in emissions that is clearly de minimis:

a. Judicial and legislative proceedings.

b. Continuing and recurring activities such as permit renewals where 

activities conducted shall be similar in scope and operation to activities currently being 

conducted.

c. Rulemaking and policy development and issuance.

d. Routine maintenance and repair activities, including repair and 

maintenance of administrative sites, roads, trails, and facilities.

e. Civil and criminal enforcement activities, such as investigations, 

audits, inspections, examinations, prosecutions, and the training of law enforcement 

personnel.

f. Administrative actions such as personnel actions, organizational 

changes, debt management, internal agency audits, program budget proposals, and 

matters relating to administration and collection of taxes, duties, and fees.

g. The routine, recurring transportation of materiel and personnel.

h. Routine movement of mobile assets, such as ships and aircraft, in 

home port reassignments and stations (when no new support facilities or personnel are 

required) to perform as operational groups and for repair or overhaul or both.

i. Maintenance dredging and debris disposal where no new depths 

are required, applicable permits are secured, and disposal shall be at an approved 

disposal site.

j. With respect to existing structures, properties, facilities, and lands 

where future activities conducted shall be similar in scope and operation to activities 

currently being conducted at the existing structures, properties, facilities, and lands, 

actions such as relocation of personnel, disposition of federally-owned existing structures, 

properties, facilities, and lands, rent subsidies, operation and maintenance cost subsidies, 

the exercise of receivership or conservatorship authority, assistance in purchasing 

structures, and the production of coins and currency.
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k. The granting of leases, licenses such as for exports and trade, 

permits, and easements where activities conducted shall be similar in scope and 

operation to activities currently being conducted.

l. Planning, studies, and provision of technical assistance.

m. Routine operation of facilities, mobile assets, and equipment.

n. Transfers of ownership, interests, and titles in land, facilities, and 

real and personal properties, regardless of the form or method of the transfer.

o. The designation of empowerment zones, enterprise communities, 

or viticultural areas.

p. Actions by any of the federal banking agencies or the federal 

reserve banks, including actions regarding charters, applications, notices, licenses, the 

supervision or examination of depository institutions or depository institution holding 

companies, access to the discount window, or the provision of financial services to 

banking organizations or to any state, agency, or instrumentality of the United States.

q. Actions by the Board of Governors of the federal reserve system 

or any federal reserve bank to effect monetary or exchange rate policy.

r. Actions that implement a foreign affairs function of the United 

States.

s. Actions or portions thereof associated with transfers of land, 

facilities, title, and real properties through an enforceable contract or lease agreement 

where the delivery of the deed is required to occur promptly after a specific, reasonable 

condition is met, such as promptly after the land is certified as meeting the requirements 

of the Comprehensive Environmental Response, Compensation, and Liability Act 

(CERCLA), and where the federal agency does not retain continuing authority to control 

emissions associated with the lands, facilities, title, or real properties.

t. Transfers of real property, including land, facilities, and related 

personal property from a federal entity to another federal entity, and assignments of real 

property, including land, facilities, and related personal property from a federal entity to 

another federal entity, for subsequent deeding to eligible applicants.

u. Actions by the Department of the Treasury to effect fiscal policy 

and to exercise the borrowing authority of the United States.
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v. Air traffic control activities and adopting approach, departure, 

and en route procedures for aircraft operations above the mixing height specified in the 

applicable implementation plan. Where the applicable implementation plan does not 

specify a mixing height, the federal agency may use the 3,000 feet above ground level 

as a default mixing height, unless the agency demonstrates that use of a different 

mixing height is appropriate because the change in emissions at and above that height 

caused by the federal action is de minimis.

3. Actions where the emissions are not reasonably foreseeable, such as the 

following:

a. Initial outer continental shelf lease sales which are made on a 

broad scale and are followed by exploration and development plans on a project level.

b. Electric power marketing activities that involve the acquisition, 

sale, and transmission of electric energy.

4. Individual actions which implement a decision to conduct or carry out a 

program that has been found to conform to the applicable implementation plan, such as 

prescribed burning actions which are consistent with a conforming land management 

plan, that has been found to conform to the applicable implementation plan. The land 

management plan shall have been found to conform within the past five years.

G. Notwithstanding the other requirements of this section, a conformity 

determination is not required for the following federal actions or portions thereof:

1. The portion of an action that includes major or minor new or modified 

stationary sources that require a permit under the new source review program.

2. Actions in response to emergencies or natural disasters such as 

hurricanes, earthquakes, etc., which that are typically commenced on the order of hours 

or days after the emergency or disaster and, if applicable, which meet the requirements of 

subsection H of this section.

3. Research, investigations, studies, demonstrations, or training (other than 

those exempted under subdivision F 2 of this section), where no environmental detriment 

is incurred, or the particular action furthers air quality research, as determined by the 

department.

4. Alteration and additions of existing structures as specifically required by 

new or existing applicable environmental legislation or environmental regulations (for 

example, hush houses for aircraft engines and scrubbers for air emissions).

5. Direct emissions from remedial and removal actions carried out under 
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CERCLA and associated regulations to the extent the emissions either comply with the 

substantive requirements of the new source review program, or are exempted from other 

environmental regulation under the provisions of CERCLA and applicable regulations 

issued under CERCLA.

H. Federal actions which are part of a continuing response to an emergency or 

disaster under subdivision G 2 of this section and which are to be taken more than six 

months after the commencement of the response to the emergency or disaster under 

subdivision G 2 of this section are exempt from the requirements of this subsection only if:

1. The federal agency taking the actions makes a written determination that, 

for a specified period not to exceed an additional six months, it is impractical to prepare 

the conformity analyses which would otherwise be required and the actions cannot be 

delayed due to overriding concerns for public health and welfare, national security 

interests, and foreign policy commitments; or

2. For actions which are to be taken after those sections actions covered by 

subdivision H 1 of this section, the federal agency makes a new determination as 

provided in subdivision H 1 of this section, and:

a. Provides a draft copy of the written determinations required to 

affected EPA regional offices, the affected states and air pollution control agencies, and 

any federally recognized Indian tribal government in the nonattainment or maintenance 

area. Those organizations shall be allowed 15 days from the beginning of the extension 

period to comment on the draft determination; and

b. Within 30 days after making the determination, publish a notice 

of the determination by placing a prominent advertisement in a daily newspaper of 

general circulation in the area affected by the action.

3. If additional actions are necessary in response to an emergency or 

disaster under subdivision G 2 of this section beyond the specified time period in 

subdivision 2 of this subsection, a federal agency may make a new written 

determination as described in subdivision 2 of this subsection for as many 6-month 

periods as needed, but in no case shall this exemption extend beyond three, 6-month 

periods except where an agency provides information to EPA and the department

stating that the conditions that gave rise to the emergency exemption continue to exist 

and how such conditions effectively prevent the agency from conducting a conformity 

evaluation.

I. Notwithstanding other requirements of this regulation, actions specified by 

individual federal agencies that have met the criteria set forth in either subsection

subdivision J 1 , or J 2 , or J 3 of this section and the procedures set forth in subsection K 

of this section are presumed to conform, except as provided in subsection M of this 
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section. Actions specified by individual federal agencies as presumed to conform shall

not be used in combination with one another when the total direct and indirect 

emissions from the combination of actions would equal or exceed any of the rates 

specified in subdivisions E 1 or E 2 of this section.

J. The federal agency shall meet the criteria for establishing activities that are 

presumed to conform by fulfilling the requirements set forth in either subsection

subdivision J 1 or 2 , 2 , or 3 of this subsection.

1. The federal agency shall clearly demonstrate, using methods consistent 

with this regulation, that the total of direct and indirect emissions from the type of activities 

which would be presumed to conform would not:

a. Cause or contribute to any new violation of any standard in any 

area;

b. Interfere with the provisions in the applicable implementation plan 

for maintenance of any standard;

c. Increase the frequency or severity of any existing violation of any 

standard in any area;

d. Delay timely attainment of any standard or any required interim 

emissions reductions or other milestones in any area including, where applicable, 

emission levels specified in the applicable implementation plan for purposes of:

(1) A demonstration of reasonable further progress;

(2) A demonstration of attainment; or

(3) A maintenance plan.

2. The federal agency shall provide documentation that the total of direct 

and indirect emissions from the future actions would be below the emission rates for a 

conformity determination that are established in subsection B of this section, based, for 

example, on similar actions taken over recent years.

3. The federal agency shall clearly demonstrate that the emissions from 

the type or category of actions and the amount of emissions from the action are 

included in the applicable implementation plan and the department provides written 

concurrence that the emissions from the actions along with all other expected 

emissions in the area will not exceed the emission budget in the applicable 

implementation plan.
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K. In addition to meeting the criteria for establishing exemptions set forth in 

subdivision J 1 or , J 2 , or J 3 of this section, the following procedures shall also be 

complied with to presume that activities shall conform:

1. The federal agency shall identify through publication in the Federal 

Register its list of proposed activities that are presumed to conform, and the analysis, 

assumptions, emissions factors, and criteria used as the basis for the presumptions. The 

notice shall clearly identify the type and size of the action that would be presumed to 

conform and provide criteria for determining if the type and size of action qualifies it for 

the presumption;

2. The federal agency shall notify the appropriate EPA regional office(s), 

department, and local air quality agencies and, where applicable, the lead planning 

organization, and the metropolitan planning organization and provide at least 30 days 

for the public to comment on the list of proposed activities presumed to conform. If the 

presumed to conform action has regional or national application (e.g., the action will 

cause emission increases in excess of the de minimis levels identified in subsection E

of this section in more than one EPA region), the federal agency, as an alternative to 

sending it to EPA regional offices, may send the draft conformity determination to EPA, 

Office of Air Quality Planning and Standards;

3. The federal agency shall document its response to all the comments 

received and make the comments, response, and final list of activities available to the 

public upon request; and

4. The federal agency shall publish the final list of the such activities in the 

Federal Register.

L. Notwithstanding the other requirements of this section, when the total of direct 

and indirect emissions of any pollutant from a federal action does not equal or exceed the 

rates specified in subsection E of this section, but represents 10% or more of a 

nonattainment or maintenance area's total emissions of that pollutant, the action is 

defined as a regionally significant action and the requirements of 9VAC5-160-110 and 

9VAC5-160-130 through 9VAC5-160-180 shall apply for the federal action. Emissions 

from the following actions are presumed to conform:

1. Actions at installations with facility-wide emission budgets meeting the 

requirements in 9VAC5-160-181 provided that the department has included the 

emission budget in the EPA-approved applicable implementation plan and the 

emissions from the action along with all other emissions from the installation will not 

exceed the facility-wide emission budget.
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2. Prescribed fires conducted in accordance with a smoke management 

program that meets the requirements of EPA's Interim Air Quality Policy on Wildland 

and Prescribed Fires or an equivalent replacement EPA policy.

3. Emissions for actions that the department identifies in the EPAapproved applicable implementation plan as presumed to conform.

M. Where an action presumed to be de minimis under subsections F 1 or F 2 of 

this section or otherwise presumed to conform under subsection I of this section is a 

regionally significant action or where an action otherwise presumed to conform under 

subsection I of this section does not in fact meet one of the criteria in subsection J 1 of 

this section, that action shall not be considered de minimis or presumed to conform and 

the requirements of 9VAC5-160-110 and 9VAC5-160-130 through 9VAC5-160-180 shall 

apply for the federal action. Even though an action would otherwise be presumed to 

conform under subsection I or L of this section, an action shall not be presumed to 

conform and the requirements of 9VAC5-160-110 through 9VAC5-160-180, 9VAC5-

160-182 through 9VAC5-160-184, and 9VAC5-160-190 shall apply to the action if EPA 

or a third party shows that the action would:

1. Cause or contribute to any new violation of any standard in any area;

2. Interfere with provisions in the applicable implementation plan for 

maintenance of any standard;

3. Increase the frequency or severity of any existing violation of any 

standard in any area; or

4. Delay timely attainment of any standard or any required interim 

emissions reductions or other milestones in any area including, where applicable, 

emission levels specified in the applicable implementation plan for purposes of (i) a 

demonstration of reasonable further progress; (ii) a demonstration of attainment; or (iii) 

a maintenance plan.

N. Any measures used to affect or determine applicability of this regulation, as 

determined under this section, shall result in projects that are in fact de minimis, shall 

result in the de minimis levels prior to the time the applicability determination is made, and 

shall be state or federally enforceable. Any measures that are intended to reduce air 

quality impacts for this purpose shall be identified (including the identification and 

quantification of all emission reductions claimed) and the process for implementation 

(including any necessary funding of the measures and tracking of the emission 

reductions) and enforcement of the measures shall be described, including an 

implementation schedule containing explicit timelines for implementation. Prior to a 

determination of applicability, the federal agency making the determination shall obtain 

written commitments from the appropriate persons or agencies to implement any 
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measures which are identified as conditions for making the determinations. The written 

commitment shall describe the mitigation measures and the nature of the commitment, in 

a manner consistent with the previous sentence. After this regulation is approved by EPA, 

enforceability through the applicable implementation plan of any measures necessary for 

a determination of applicability shall apply to all persons who agree to reduce direct and 

indirect emissions associated with a federal action for a conformity applicability 

determination.

9VAC5-160-40. Authority of board and department.

A. No provision of this regulation shall limit the power of the board to take such 

appropriate action as necessary to control and abate air pollution in emergency situations.

B. In accordance with the Virginia Air Pollution Control Law and the Administrative 

Process Act and by the adoption of this regulation, the board confers upon the 

department the administrative, enforcement and decision making authority enumerated in 

this regulation.

C. The board reserves the right to exercise its authority in any of the powers 

delegated in this regulation should it choose to do so.

D. The director has final authority to adjudicate contested decisions of 

subordinates delegated powers by the director prior to appeal of the decisions to the 

circuit court or consideration by the board.

9VAC5-160-50. Repealed.

9VAC5-160-60. Repealed.

9VAC5-160-70. Repealed.

9VAC5-160-80. Relationship of state regulations to federal regulations.

A. In order for the Commonwealth of Virginia to fulfill its obligations under the 

federal Clean Air Act, some provisions of this regulation are required to be approved by 

EPA and when approved those provisions become federally enforceable.

B. In cases where this regulation specifies that procedures or methods shall be 

approved by, acceptable to, or determined by the board or department or other similar 

phrasing or specifically provide for decisions to be made by the board or department, it 

may be necessary to have the actions (approvals determinations, exemptions, exclusions, 

or decisions) reviewed and confirmed as acceptable or approved by EPA in order to 

make them federally enforceable. Determination of which state actions require federal 

confirmation or approval and the administrative mechanism for making associated 
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confirmation or approval decisions shall be made on a case-by-case basis in accordance 

with EPA regulations and policy.

9VAC5-160-90. Repealed.

PART III.

CRITERIA AND PROCEDURES FOR

MAKING CONFORMITY DETERMINATIONS.

9VAC5-160-110. General.

A. No federal agency shall engage in, support in any way, or provide financial 

assistance for, license, or permit, or approve any activity which does not conform to an 

applicable implementation plan.

B. A federal agency must make a determination that a federal action conforms to 

the applicable implementation plan in accordance with the requirements of this regulation 

before the action is taken.

C. Subsection B of this section does not include federal actions where either:

1. A NEPA analysis was completed as evidenced by a final environmental 

assessment, environmental impact statement, or finding of no significant impact that was 

prepared prior to January 31, 1994, or

2. a. Prior to January 31, 1994, an environmental assessment was 

commenced or a contract was awarded to develop the specific environmental analysis,

b. Sufficient environmental analysis is completed by March 15, 1994, 

so that the federal agency may determine that the federal action is in conformity with the 

specific requirements and the purposes of the applicable implementation plan pursuant to 

the agency's affirmative obligation under § 176(c) of the federal Clean Air Act, and

c. A written determination of conformity under § 176(c) of the federal 

Clean Air Act has been made by the federal agency responsible for the federal action by 

March 15, 1994 Reserved.

D. Notwithstanding any provision of this regulation, a determination that an action 

is in conformity with the applicable implementation plan does not exempt the action from 

any other requirements of the applicable implementation plan, NEPA, or the federal Clean

Air Act.

E. If an action would result in emissions originating in more than one 

nonattainment or maintenance area, the conformity must be evaluated for each area 
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separately.

9VAC5-160-120. Conformity analysis Federal agency conformity responsibility.

Any federal agency taking an action subject to this regulation department, 

agency, or instrumentality of the federal government taking an action subject to this 

regulation shall make its own conformity determination consistent with the requirements 

of this part. In making its conformity determination, a federal agency shall follow the 

requirements in 9VAC5-160-130 through 9VAC5-160-180 and 9VAC5-160-182 through 

9VAC5-160-185, and shall consider comments from any interested parties. Where 

multiple federal agencies have jurisdiction for various aspects of a project, a federal 

agency may choose to adopt the analysis of another federal agency (to the extent the 

proposed action and impacts analyzed are the same as the project for which a conformity 

determination is required) or develop its own analysis in order to make its conformity 

determination.

9VAC5-160-130. Reporting requirements.

A. A federal agency making a conformity determination under 9VAC5-160-160

9VAC5-160-120 through 9VAC5-160-180 and 9VAC5-160-181 through 9VAC5-160-184

shall provide to the appropriate EPA regional office or offices, department and local air 

quality agencies, any federally-recognized Indian tribal government in the nonattainment 

or maintenance area, and, where applicable, affected federal land managers, the lead 

planning organization, and the metropolitan planning organization, a 30-day notice which 

describes the proposed action and the federal agency's draft conformity determination on 

the action. If the action has multi-regional or national impacts (e.g., the action will cause 

emission increases in excess of the de minimis levels identified in 9VAC5-160-30 E in 

three or more EPA regions), the federal agency, as an alternative to sending it to EPA 

regional offices, may provide the notice to EPA's Office of Air Quality Planning and 

Standards.

B. A federal agency shall notify the appropriate EPA regional office(s), department 

and local air quality agencies, any federally-recognized Indian tribal government in the 

nonattainment or maintenance area, and, where applicable, affected federal land 

managers, the lead planning organization, and the metropolitan planning organization 

within 30 days after making a final conformity determination under 9VAC5-160-160.

C. The draft and final conformity determination shall exclude any restricted 

information or confidential business information. The disclosure of restricted information 

and confidential business information shall be controlled by the applicable laws, 

regulations, security manuals, or executive orders concerning the use, access, and 

release of such materials. Subject to applicable procedures to protect restricted 

information from public disclosure, any information or materials excluded from the draft 

or final conformity determination or supporting materials may be made available in a 
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restricted information annex to the determination for review by federal and department

representatives who have received appropriate clearances to review the information.

9VAC5-160-140. Public participation.

A. Upon request by any person regarding a specific federal action, a federal 

agency shall make available, subject to the limitation in subsection E of this section, for 

review its draft conformity determination under 9VAC5-160-160 with supporting materials 

which describe the analytical methods and conclusions relied upon in making the 

applicability analysis and draft conformity determination.

B. A federal agency shall make public its draft conformity determination under 

9VAC5-160-160 by placing a notice by prominent advertisement in a daily newspaper of 

general circulation in the area affected by the action and by providing 30 days for written 

public comment prior to taking any formal action on the draft determination. This 

comment period may be concurrent with any other public involvement such as occurs in 

the NEPA process. If the action has multi-regional or national impacts (e.g., the action 

will cause emission increases in excess of the de minimis levels identified in 9VAC5-

160-30 E in three or more EPA regions), the federal agency, as an alternative to 

publishing separate notices, may publish a notice in the Federal Register.

C. A federal agency shall document its response to all the comments received on 

its draft conformity determination under 9VAC5-160-160 and make the comments and 

responses available, subject to the limitation in subsection E of this section, upon 

request by any person regarding a specific federal action, within 30 days of the final 

conformity determination.

D. A federal agency shall make public its final conformity determination under 

9VAC5-160-160 for a federal action by placing a notice by prominent advertisement in a 

daily newspaper of general circulation in the area affected by the action within 30 days of 

the final conformity determination. If the action would have multi-regional or national 

impacts, the federal agency, as an alternative, may publish the notice in the Federal 

Register.

E. The draft and final conformity determination shall exclude any restricted 

information or confidential business information. The disclosure of restricted information 

and confidential business information shall be controlled by the applicable laws, 

regulations or executive orders concerning the release of such materials.

9VAC5-160-150. Frequency of conformity determinations Reevaluation of conformity.

A. Once a conformity determination is completed by a federal agency, that 

determination is not required to be re-evaluated if the agency has maintained a 

continuous program to implement the action; the determination has not lapsed as 
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specified in subsection B of this section; or any modification to the action does not 

result in an increase in emissions above the levels specified in 9VAC5-160-30 B. If a 

conformity determination is not required for the action at the time NEPA analysis is 

completed, the date of the finding of no significant impact for an environmental 

assessment, a record of decision for an environmental impact statement, or a 

categorical exclusion determination may be used as a substitute date for the conformity 

determination date.

B. The conformity status of a federal action automatically lapses five years from 

the date a final conformity determination is reported under 9VAC5-160-130, unless the 

federal action has been completed or a continuous program has been commenced to 

implement that the federal action within a reasonable time has commenced.

B C. Ongoing federal activities at a given site showing continuous progress are not 

new actions and do not require periodic redeterminations so long as the such activities 

are within the scope of the final conformity determination reported under 9VAC5-160-130.

C D. If, after the conformity determination is made, the federal action is changed 

so that there is an increase in the total of direct and indirect emissions above the levels in 

9VAC5-160-30 E, a new conformity determination is required. If the federal agency 

originally determined through the applicability analysis that a conformity determination 

was not necessary because the emissions for the action were below the limits in 

9VAC5-160-30 B and changes to the action would result in the total emissions from the 

action being above the limits in 9VAC5-160-30 B, then the federal agency shall make a 

conformity determination.

9VAC5-160-160. Criteria for determining conformity of general federal actions.

A. Any An action required under 9VAC5-160-30 to have a conformity 

determination for a specific pollutant, shall be determined to conform to the applicable 

implementation plan if, for each pollutant that exceeds the rates in 9VAC160-30 E, or 

otherwise requires a conformity determination due to the total of direct and indirect 

emissions from the action, the action meets the requirements of subsection C of this 

section, and meets any of the following requirements:

1. For any criteria pollutant or precursor, the total of direct and indirect 

emissions from the action are specifically identified and accounted for in the applicable 

implementation plan's attainment or maintenance demonstration or reasonable further 

progress milestone or in a facility-wide emission budget included in an applicable 

implementation plan in accordance with 9VAC5-160-181;

2. For precursors of ozone or , nitrogen dioxide, or particulate matter, the 

total of direct and indirect emissions from the action are fully offset within the same 

nonattainment or maintenance area (or nearby area of equal or higher classification 
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provided the emissions from that area contribute to the violations, or have contributed 

to violations in the past, in the area with the federal action) through a revision to the 

applicable implementation plan or a similarly enforceable measure that effects emission 

reductions so that there is no net increase in emissions of that pollutant;

3. For any directly-emitted criteria pollutant, except ozone and nitrogen 

dioxide, the total of direct and indirect emissions from the action meet meets the 

requirements:

a. Specified in subsection B of this section, based on areawide air 

quality modeling analysis and local air quality modeling analysis; or

b. Meet the requirements of subdivision 5 of this section, and, for 

local air quality modeling analysis, the requirement of subsection B of this section;

4. For carbon monoxide or directly emitted PM10 particulate matter:

a. Where the department determines (in accordance with 9VAC5-

160-120 and 9VAC5-160-130 and consistent with the applicable implementation plan) 

that an areawide air quality modeling analysis is not needed, the total of direct and 

indirect emissions from the action meet the requirements specified in subsection B of this 

section, based on local air quality modeling analysis; or

b. Where the department determines (in accordance with 9VAC5-

160-120 and 9VAC5-160-130 and consistent with the applicable implementation plan) 

that an areawide air quality modeling analysis is appropriate and that a local air quality 

modeling analysis is not needed, the total of direct and indirect emissions from the action 

meet the requirements specified in subsection B of this section, based on areawide 

modeling, or meet the requirements of subdivision 5 of this section; or

5. For ozone or nitrogen dioxide, and for the purposes of subdivisions 3 b 

and 4 b of this subsection, each portion of the action or the action as a whole meets any 

of the following requirements:

a. Where EPA has approved a revision to an area's attainment or 

maintenance demonstration after 1990 the applicable implementation plan after the area 

was designated as nonattainment and the department makes a determination that as 

provided in subdivision 5 a (1) of this subsection or where the Commonwealth of Virginia

makes a commitment as provided in subdivision 5 a (2) of this section:

(1) The total of direct and indirect emissions from the action or 

portion thereof is determined and documented by the department to result in a level of 

emissions which, together with all other emissions in the nonattainment or maintenance 

area, would not exceed the emissions budgets specified in the applicable implementation 
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plan.

(2) The total of direct and indirect emissions from the action or 

portion thereof is determined and documented by the department to result in a level of 

emissions which, together with all other emissions in the nonattainment or maintenance 

area, would exceed an emissions budgets specified in the applicable implementation plan 

and the governor or the governor's designee for state implementation plan actions makes 

a written commitment to EPA which includes the following:

(a) A specific schedule for adoption and submittal of a 

revision to the applicable implementation plan which would achieve the needed emissions 

reductions prior to the time emissions from the federal action would occur;

(b) Identification of specific measures for incorporation 

into the applicable implementation plan which would result in a level of emissions which, 

together with all other emissions in the nonattainment or maintenance area, would not 

exceed any emissions budget specified in the applicable implementation plan.

(c) A demonstration that all existing applicable 

implementation plan requirements are being implemented in the area for the pollutants 

affected by the federal action, and that local authority to implement additional 

requirements has been fully pursued;

(d) A determination that the responsible federal 

agencies have required all reasonable mitigation measures associated with their action; 

and

(e) Written documentation including all air quality 

analyses supporting the conformity determination;

(3) Where a federal agency made a conformity determination 

based on a commitment from the Commonwealth of Virginia under subdivision 5 a (2) of 

this subsection, and the department has submitted an implementation plan to EPA 

covering the time period during which the emissions will occur or is scheduled to submit 

such an implementation plan within 18 months of the conformity determination, the 

commitment is automatically deemed a call for a revision to the applicable implementation 

plan by EPA under § 110(k)(5) of the federal Clean Air Act, effective on the date of the 

federal conformity determination and requiring response within 18 months or any shorter 

time within which the Commonwealth of Virginia commits to revise the applicable 

implementation plan;

(4) Where a federal agency made a conformity 

determination based on a commitment from the Commonwealth of Virginia under 

subdivision 5 a (2) of this subsection and the department has not submitted an 
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implementation plan covering the time period when the emissions will occur or is not 

scheduled to submit such an implementation plan within 18 months of the conformity 

determination, the department will, within 18 months, submit to EPA a revision to the 

existing implementation plan committing to include the emissions in the future 

implementation plan revision.

b. The action or portion thereof, as determined by the metropolitan 

planning organization, is specifically included in a current transportation plan and 

transportation improvement program which have been found to conform to the applicable 

implementation plan under 40 CFR Part 51, subpart T, or 40 CFR Part 93, subpart A;

c. The action or portion thereof fully offsets its emissions within the 

same attainment nonattainment or maintenance area (or nearby area of equal or higher 

classification provided the emissions from that area contribute to the violations, or have 

contributed to violation in the past, in the area with the federal action) through a revision 

to the applicable implementation plan or an equally enforceable measure that effects 

emissions reductions equal to or greater than the total of direct and indirect emissions 

from the action so that there is no net increase in emissions of that pollutant;

d. Where EPA has not approved a revision to the relevant 

implementation plan attainment or maintenance demonstration since 1990 since the area 

was designated or reclassified, the total of direct and indirect emissions from the action 

for the future years (described in 9VAC5-160-170) do not increase emissions with respect 

to the baseline emissions;

(1) The baseline emissions reflect the historical activity levels 

that occurred in the geographic area affected by the proposed federal action during:

(a) Calendar year 1990 ; The most current calendar 

year with a complete emissions inventory available before an area is designated unless 

EPA sets another year; or

(b) The calendar year that is the basis for the 

classification (or, where the classification is based on multiple years, the year that is most 

representative in terms of the level of activity), if a classification is promulgated in 40 CFR 

Part 81 The emission budget in the applicable implementation plan; or

(c) The year of the baseline inventory in the PM10-

applicable implementation plan;

(2) The baseline emissions are the total of direct and indirect 

emissions calculated for the future years (described in 9VAC5-160-170 D) using the 

historic activity levels (described in subdivision 5 d (1) of this subsection) and appropriate 

emission factors for the future years; or
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e. Where the action involves regional water or wastewater projects or 

both, the projects are sized to meet only the needs of population projections that are in 

the applicable implementation plan, based on assumptions regarding per capita use that 

are developed or approved in accordance with 9VAC5-160-170 A.

B. The areawide or local air quality modeling analyses or both shall:

1. Meet the requirements of 9VAC5-160-170; and

2. Show that the action does not:

a. Cause or contribute to any new violation of any standard in any 

area; or

b. Increase the frequency or severity of any existing violation of any 

standard in any area.

C. Notwithstanding any other requirements of this section, an action subject to this 

section may not be determined to conform to the applicable implementation plan unless 

the total of direct and indirect emissions from the action is in compliance or consistent 

with all relevant requirements and milestones contained in the applicable implementation 

plan, such as elements identified as part of the reasonable further progress schedules, 

assumptions specified in the attainment or maintenance demonstration, prohibitions, 

numerical emission limits, and work practice requirements, and the action is otherwise in 

accordance with all relevant requirements of the applicable implementation plan.

D. Any analyses required under this section shall be completed, and any mitigation 

requirements necessary for a finding of conformity shall be identified in accordance with 

9VAC5-160-180 before the determination of conformity is made.

9VAC5-160-170. Procedures for conformity determinations.

A. The analyses required under this section shall be based on the latest planning 

assumptions.

1. All planning assumptions (including, but not limited to, per capita water 

and sewer use, vehicle miles traveled per capita or per household, trip generation per 

household, vehicle occupancy, household size, vehicle fleet mix, vehicle ownership, wood 

stoves per household, and the geographic distribution of population growth) shall be 

derived from the estimates of current and future population, employment, travel, and 

congestion most recently approved by the metropolitan planning organization or other 

agency authorized to make the estimates, where available. The conformity determination 

shall also be based on the latest assumptions about current and future background 
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concentrations and other federal actions.

2. Any revisions to these estimates used as part of the conformity 

determination, including projected shifts in geographic location or level of population, 

employment, travel, and congestion shall be approved by the metropolitan planning 

organization or other agency authorized to make the estimates for the urban area.

B. The analyses required under this subsection shall be based on the latest and 

most accurate emission estimation techniques available as described below, unless the

such techniques are inappropriate. If the such techniques are inappropriate and , the 

federal agency may obtain written approval of from the appropriate EPA Regional 

Administrator is obtained for any a modification or substitution, they may be modified or of

another technique substituted on a case-by-case basis or, where appropriate, on a 

generic basis for a specific federal agency program.

1. For motor vehicle emissions, the most current version of the motor 

vehicle emissions model specified by EPA for use in the preparation or revision of the 

applicable implementation plan shall be used for the conformity analysis as specified in 

subdivisions 1 a and 1 b of this subsection.

a. The EPA shall publish in the Federal Register a notice of 

availability of any new motor vehicle emissions model.

b. A grace period of three months shall apply during which the motor 

vehicle emissions model previously specified by EPA as the most current version may be 

used unless EPA announces a longer grace period in the Federal Register. Conformity 

analyses for which the analysis was begun during the grace period or no more than three

years months before the Federal Register notice of availability of the latest emission 

model may continue to use the previous version of the model specified by EPA, if a final 

conformity determination is made within 3 years of the analysis.

2. For non-motor vehicle sources, including stationary and area source 

emissions, the latest emission factors specified by EPA in the "Compilation of Air 

Pollutant Emission Factors (AP-42)" shall be used for the conformity analysis unless more 

accurate emission data are available, such as actual stack test data from stationary 

sources which are part of the conformity analysis.

C. The air quality modeling analyses required under this subpart section shall be 

based on the applicable air quality models, databases, and other requirements specified 

in Appendix W of 40 CFR Part 51, unless:

1. The guideline techniques are inappropriate, in which case the model may 

be modified or another model substituted on a case-by-case basis, or, where appropriate, 

on a generic basis for a specific federal agency program; and
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2. Written approval of the EPA Regional Administrator is obtained for any 

modification or substitution.

D. The analyses required under this subsection, except 9VAC5-160-160 A 1, shall 

be based on the total of direct and indirect emissions from the action and shall reflect 

emission scenarios that are expected to occur under each of the following cases:

1. The federal Clean Air Act-mandated attainment year specified in the 

applicable implementation plan or, if applicable, the farthest year for which emissions are 

projected in the maintenance plan if the applicable implementation plan does not specify 

an attainment year, the latest attainment year possible under the federal Clean Air Act; or

2. The year during which the total of direct and indirect emissions from the 

action is expected to be the greatest on an annual basis; and last year for which 

emissions are projected in the maintenance plan;

3. The year during which the total of direct and indirect emissions from the 

action is expected to be the greatest on an annual basis; and

4. Any year for which the applicable implementation plan specifies an 

emissions budget.

9VAC5-160-180. Mitigation of air quality impacts.

A. Any measures that are intended to mitigate air quality impacts shall be identified 

(including the identification and quantification of all emission reductions claimed) and the 

process for implementation (including any necessary funding of the measures and 

tracking of the emission reductions) and enforcement of the measures shall be described, 

including an implementation schedule containing explicit timelines for implementation.

B. Prior to determining that a federal action is in conformity, the federal agency 

making the conformity determination shall obtain written commitments from the 

appropriate persons or agencies to implement any mitigation measures which are 

identified as conditions for making conformity decisions. The written commitment shall 

describe the mitigation measures and the nature of the commitment, in a manner 

consistent with subsection A of this section.

C. Persons or agencies voluntarily committing to mitigation measures to facilitate 

positive conformity determinations shall comply with the obligations of the commitments.

D. In instances where the federal agency is licensing, permitting, or otherwise 

approving the action of another governmental or private entity, approval by the federal 

agency shall be conditioned on the other entity meeting the mitigation measures set forth 
COMMONWEALTH OF VIRGINIA PAGE 30 of 35

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in the conformity determination as provided in subsection A of this section.

E. When necessary because of changed circumstances, mitigation measures may 

be modified so long as the new mitigation measures continue to support the conformity 

determination in accordance with 9VAC5-160-150 and 9VAC5-160-160 and this section.

Any proposed change in the mitigation measures is subject to the reporting requirements 

of 9VAC5-160-130 and the public participation requirements of 9VAC5-160-140.

F. Written comments to mitigation measures shall be obtained prior to a positive 

conformity determination, and the such commitments shall be fulfilled.

G. After EPA approves this regulation, any agreements, including mitigation 

measures, necessary for a conformity determination shall be both state and federally 

enforceable. Enforceability through the applicable implementation plan shall apply to all 

persons who agree to mitigate direct and indirect emissions associated with a federal 

action for a conformity determination.

9VAC5-160-181. Conformity evaluation for federal installations with facility-wide 

emission budgets.

A. The department may, in cooperation with federal agencies or third parties 

authorized by the agency that operate installations subject to federal oversight, develop 

and adopt a facility-wide emission budget to be used for demonstrating conformity 

under 9VAC5-160-160 A 1. The facility-wide budget shall meet the following criteria:

1. Be for a set time period;

2. Cover the pollutants or precursors of the pollutants for which the area is 

designated nonattainment or maintenance;

3. Include specific quantities allowed to be emitted on an annual or 

seasonal basis;

4. The emissions from the facility along with all other emissions in the 

area will not exceed the emission budget for the area;

5. Include specific measures to ensure compliance with the budget, such 

as periodic reporting requirements or compliance demonstration, when the federal 

agency is taking an action that would otherwise require a conformity determination;

6. Be submitted to EPA as a revision to the applicable implementation 

plan; and
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7. The revision to the applicable implementation plan shall be approved by 

EPA.

B. The facility-wide budget developed and adopted in accordance with 

subsection A of this section may be revised by following the requirements in subsection 

A of this section.

C. Total direct and indirect emissions from federal actions in conjunction with all 

other emissions subject to general conformity from the facility that do not exceed the 

facility budget adopted pursuant to subsection A of this section are presumed to 

conform to the applicable implementation plan and do not require a conformity analysis.

D. If the total direct and indirect emissions from the federal actions in conjunction 

with the other emissions subject to general conformity from the facility exceed the 

budget adopted pursuant to subsection A of this section, the action shall be evaluated 

for conformity. A federal agency may use the compliance with the facility-wide 

emissions budget as part of the demonstration of conformity, i.e., the agency would 

have to mitigate or offset the emissions that exceed the emission budget.

E. If the applicable implementation plan for the area includes a category for 

construction emissions, the negotiated budget may exempt construction emissions from 

further conformity analysis.

9VAC5-160-182. Emissions beyond the time period covered by the applicable 

implementation plan.

If a federal action would result in total direct and indirect emissions above 

the applicable thresholds which would be emitted beyond the time period covered by 

the applicable implementation plan, the federal agency may (i) demonstrate conformity 

with the last emission budget in the applicable implementation plan; or (ii) request the 

Commonwealth of Virginia to adopt an emissions budget for the action for inclusion in 

the applicable implementation plan. The Commonwealth of Virginia will submit a

revision of the applicable implementation plan to EPA within 18 months either including 

the emissions in the existing implementation plan or establishing an enforceable 

commitment to include the emissions in future revisions to the applicable 

implementation plan based on the latest planning assumptions at the time of the 

revision to the applicable implementation plan. No such commitment by the 

Commonwealth of Virginia shall restrict the Commonwealth of Virginia's ability to 

require RACT, RACM or any other control measures within the Commonwealth of 

Virginia's authority to ensure timely attainment of the national ambient air quality 

standards.

9VAC5-160-183. Timing of offsets and mitigation measures.
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A. The emissions reductions from an offset or mitigation measure used to 

demonstrate conformity shall occur during the same calendar year as the emission 

increases from the action except, as provided in subsection B of this section.

B. The department may approve emissions reductions in other years provided:

1. The reductions are greater than the emission increases by the following 

ratios:

Extreme nonattainment areas: 1.5:1

Severe nonattainment areas: 1.3:1

Serious nonattainment areas: 1.2:1

Moderate nonattainment areas: 1.15:1

All other areas: 1.1:1

2. The time period for completing the emissions reductions shall not 

exceed twice the period of the emissions.

3. The offset or mitigation measure with emissions reductions in another 

year shall not:

a. Cause or contribute to a new violation of any air quality standard;

b. Increase the frequency or severity of any existing violation of any 

air quality standard; or

c. Delay the timely attainment of any standard or any interim 

emissions reductions or other milestones in any area.

C. The approval by the department of an offset or mitigation measure with 

emissions reductions in another year does not relieve the Commonwealth of Virginia of 

any obligation to meet any implementation plan or federal Clean Air Act milestone or

deadline. The approval of an alternate schedule for mitigation measures is at the 

discretion of the department, and it is not required to approve an alternate schedule.

9VAC5-160-184. Inter-precursor mitigation measures and offsets.

Federal agencies shall reduce the same type of pollutant as being 

increased by the federal action except the department may approve offsets or 

mitigation measures of different precursors of the same criteria pollutant, if such trades 

are allowed by the Commonwealth of Virginia in 9VAC5-80 (Permits for Stationary 

Sources) as approved in the applicable implementation plan, is technically justified, and 

has a demonstrated environmental benefit.
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9VAC5-160-185. Early emission reduction credit programs at federal facilities and 

installation subject to federal oversight.

A. Federal facilities and installations subject to federal oversight may, with the 

approval of the department, create an early emissions reductions credit program. The 

federal agency may create the emission reduction credits in accordance with the 

requirements in subsection B of this section and use them in accordance with 

subsection C of this section.

B. Creation of emission reduction credits shall be accomplished as follows.

1. Emissions reductions shall be quantifiable through the use of standard 

emission factors or measurement techniques. If non-standard factors or techniques to 

quantify the emissions reductions are used, the federal agency shall receive approval 

from the department and from the EPA regional office. The emission reduction credits 

do not have to be quantified before the reduction strategy is implemented, but shall be 

quantified before the credits are used in the general conformity evaluation.

2. The emission reduction methods shall be consistent with the applicable 

implementation plan attainment and reasonable further progress demonstrations.

3. The emissions reductions shall not be required by or credited to other 

applicable implementation plan provisions.

4. Both the department and federal air quality agencies shall be able to 

take legal action to ensure continued implementation of the emission reduction 

strategy. In addition, private citizens shall also be able to initiate action to ensure 

compliance with the control requirement.

5. The emissions reductions shall be permanent or the timeframe for the 

reductions shall be specified.

6. The federal agency shall document the emissions reductions and 

provide a copy of the document to the department and the EPA regional office for 

review. The documentation shall include a detailed description of the emission 

reduction strategy and a discussion of how it meets the requirements of subdivisions 1 

through 5 of this subsection.

C. The emission reduction credits created in accordance with subsection B of 

this section may be used, subject to the following limitations, to reduce the emissions 

increase from a federal action at the facility for the conformity evaluation.

1. If the technique used to create the emission reduction is implemented 

at the same facility as the federal action and could have occurred in conjunction with 
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the federal action, then the credits may be used to reduce the total direct and indirect 

emissions used to determine the applicability of the regulation as required in 9VAC5-

160-30 and as offsets or mitigation measures required by 9VAC5-160-160.

2. If the technique used to create the emission reduction is not 

implemented at the same facility as the federal action or could not have occurred in 

conjunction with the federal action, then the credits shall not be used to reduce the total 

direct and indirect emissions used to determine the applicability of the regulation as 

required in 9VAC5-160-30, but may be used to offset or mitigate the emissions as 

required by 9VAC5-160-160.

3. Emissions reductions credits shall be used in the same year in which 

they are generated.

4. Once the emission reduction credits are used, they shall not be used as 

credits for another conformity evaluation. However, unused credits from a strategy used 

for one conformity evaluation may be used for another conformity evaluation as long as 

the reduction credits are not double counted.

5. Federal agencies shall notify the department and the EPA regional 

office when the emission reduction credits are being used.

9VAC5-160-190. Savings provision.

The federal conformity rules under 40 CFR Part 51 subpart W, in addition to any 

existing applicable Commonwealth of Virginia requirements, shall establish the conformity 

criteria and procedures necessary to meet the requirements of § 176(c) of the federal 

Clean Air Act until such time as this regulation is approved by EPA. Following EPA 

approval of this regulation, the approved or approved portion of this regulation shall 

govern conformity determinations and the federal conformity regulations contained in 40 

CFR Part 93 shall apply only for the portion, if any, of this regulation that is not approved 

by EPA requirements of 40 CFR Part 93 to demonstrate conformity required under §

176(c) of the federal Clean Air Act apply to all federal actions in designated 

nonattainment and maintenance areas where EPA has not approved this regulation. 

When EPA approves this regulation in a revision to the Commonwealth of Virginia

applicable implementation plan, a conformity evaluation is governed by the approved or 

approved portion of this regulation. The regulations contained in 40 CFR Part 93 apply 

only for the portions, if any, of the 40 CFR Part 93 requirements not contained in the 

provisions of this regulation approved by EPA. In addition, any previously applicable 

implementation plan requirements relating to conformity shall remain enforceable until the 

Commonwealth of Virginia revises its applicable implementation plan to specifically 

remove them and that revision is approved by EPA approves the revision to the 

Commonwealth of Virginia's applicable implementation plan to specifically include the 

revised requirements or remove requirements.
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9VAC5-160-200. Review and confirmation of this chapter by board (Repealed).

A. Prior to January 1, 2000, the department shall provide the board with an 

analysis to include (i) an assessment of the effectiveness of this chapter, (ii) the status of 

any specific federal requirements and the identification of any provisions more stringent 

than the federal requirements, (iii) the federal approval status of this chapter and (iv) an 

assessment of the need for continuation of this chapter.

B. Upon review of the department's analysis, the board shall confirm (i) the 

continuation of this chapter, (ii) the repeal of this chapter or (iii) the need to amend this 

chapter. If a decision is made in either of the latter two cases, the board shall authorize 

the department to initiate the applicable regulatory process to carry out the decision of the 

board.

DOCUMENTS INCORPORATED BY REFERENCE

Compilation of Air Pollutant Emission Factors (AP-42), September 1985, with Supplement 

B, September 1988; Supplement C, September 1990; and Supplement D, September 

1991. Volume I: Stationary and Area Sources, stock number 055-000-00500-1, 1995; 

Supplement A, stock number 055-000-00551-6, 1996; Supplement B, stock number 

055-000-00565, 1997; Supplement C, stock number 055-000-00587-7, 1997; 

Supplement D, 1998; Supplement E, 1999; Supplement F, 2000

(http:/www.epa.gov/ttn/chiefs/efpac).

EPA's Interim Air Quality Policy on Wildland and Prescribed Fires. U.S. EPA, April 23, 

1998.

REG\DEV\F10-REG-FIN