'I 

STATE OF COLORA.DO 

Bill Ritter, Jr., Governor 

Martha E. Rudolph, Executive Director 

Dedicated to protecting and improving the health and environment of the people of Colorado 

4300 Cherry Creek Dr. S. Laboratory Services Division 

Denver, Colorado 80246-1530 8100 Lowry Blvd. 

Phone (303) 692-2000 Denver, Colorado 80230-6928 

TDD Line (303) 691-7700 (303) 692-3090 

Located in Glendale, Colorado 

http://www .cdphe .state .co. us 

June 4, 2010 

Callie Videtich, 

Air Program Director 

U.S. Environmental Protection Agency Region 8 

1595 Wynkoop St. 

Denver, Colorado 80202-1129 

Dear Ms. Videtich: 

Colorado Department 

of Public Health 

and Environment 

I am submitting this letter and attachment in response to the U.S. Environmental Protection Agency's request to 

certify that Colorado meets the requirements of Section llO(a)(l) and (2) of the Clean Air Act for the 2006 

PM2.5 National Ambient Air Quality Standards. 

Colorado has a well developed regulatory program that meets the "infrastructure" elements for State 

Implementation Plans as outlined in CAA Section llO(a)(l) and (2) for all NAAQS. With regard specifically to 

the 2006 PM2.5 standard, the Colorado Air Quality Control Commission has full authority to regulate particulate 

emissions, regardless of size. 

In regard to interstate transport, Colorado commits to prepare the appropriate demonstration showing that 

Colorado is complying with the significant contributions to nonattainment and the interference with maintenance 

provisions for the 2006 PM2.5 standard. Such a demonstration will be brought to the Colorado Air Quality 

Control Commission in 2010 for submittal to EPA in 2011. For prevention of significant deterioration and 

visibility, Colorado submitted a SIP revision on March 31, 2010 that addresses these portions of interstate 

transport. 

The attached document outlines the Colorado provisions, programs and efforts to meet the requirements of 

Section llO(a) (1) and (2) of the Clean Air Act. The document is not intended to modify or amend any portion or 

provision of Colorado's SIP. 

Martha E. Rudolph 

. Executive Director 

Attachment 

cc: Monica S. Morales, Unit Chief, Air Quality Planning and Management Unit, U.S. EPA Region 8 

Kathy Dolan, Air Quality Planning and Management Unit, U.S. EPA Region 8 

Paul Tourangeau, Director, Air Pollution Control Division, CDPHE 

Doug Lempke, Technical Secretary, Colorado Air Quality Control Commission 
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State of Colorado Provisions to Meet the Requirements 

of Section llO(a) (1) and (2) of the Clean Air Act 

Section 110 (a)(l) State Implementation Plan for National Ambient Air Quality Standards 

Colorado has established the following State Implementation Plan elements to address criteria 

pollutants in areas that have violated the National Ambient Air Quality Standards (NAAQS) 

Section 110 (a)(2)(A)- Emission Limits and Other Control Measures 

Enforceable emission limits and control measures are detailed in the various Air Quality Control 

Commission regulations for all sources of criteria pollutants as well as hazardous air pollutants, 

VOCs, CFCs, smoke and odors. A summary ofthe regulations is found below under section 110 

(a)(2)(C). 

Section 110 (a)(2)(B)- Ambient Air Quality Monitoring and Data System 

The provisions for episode monitoring, data compilation and reporting, public availability of 

information, and annual network reviews are found in the statewide monitoring SIP which was 

approved by EPA on July 9, 1980 (45 FR 46073) and August 11, 1980 (45 FR 53147). The State 

has since revised the monitoring SIP to include all new federal requirements. The revised SIP 

includes a commitment to operate a particulate monitoring network in accordance with EPA 

regulations (40 CFR Part 58.20 and Appendices A through G). The Colorado Air Quality Control 

Commission adopted monitoring SIP revisions on March 18, 1993. 

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Colorado 110 SIP Elements 

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As part of the Monitoring SIP, Colorado submits a Colorado Annual Monitoring Network Plan each 

year for EPA approval. The plan details monitoring locations for all criteria pollutants, including 

PM 2.5, and lists the quality assurance accuracy audits and precision check methods performed for 

each monitor. The Colorado Air Pollution Control Division periodically submits a Quality 

Management Plan and a Quality Assurance Project Plan to EPA Region VIII. These plans cover 

procedures to monitor, analyze data and report data to an EPA central database. The State of 

Colorado has an approved monitoring SIP, a plan and authority for monitoring, and the ability to 

properly handle all related data. 

Section 110 (a)(2)(C)- Program for Enforcement of Control Measures 

Colorado has an approved SIP regulating the construction and modification of stationary sources as 

necessary to assure that the National Ambient Air Quality Standards are achieved (Colorado Air 

Quality Control Commission Regulation 3), including a permit program as required in Parts C and 

D of the federal Clean Air Act. Colorado has an approved SIP which provides for the enforcement 

of the control measures required by Clean Air Act Section 110 (a)(2)(C). 

Many of the Colorado Air Quality Control Commission (AQCC) Regulations address in some 

manner the programs for enforcement of control measures. Some of these AQCC regulations and 

other relevant Colorado-specific programs that are in the SIP are described below: 

~ Regulation 1, Particulates, Smokes, Carbon Monoxide, and Sulfur Dioxides -- Regulation 1 sets 

forth emissions limitations, equipment requirements, and work practices (abatement and control 

measures) intended to control the emissions of particulates, smoke and sulfur oxides from new 

and existing stationary sources. Control measures specified in this regulation are designed to 

limit emissions into the atmosphere and thereby minimize the ambient concentrations of 

particulates and sulfur dioxides. 

~ Regulation 3, Stationary Source Permitting and Air Pollution Emission Notice Requirements --

Regulation 3 provides for a procedural permitting program and requires air pollution sources to 

file Air Pollution Emissions Notices (APENs). The regulation also requires that new or 

modified sources of air pollution, with certain exemptions, obtain preconstruction permits. 

Regulation 3 has been revised to incorporate PM2.5 emissions, requiring major sources in the 

state to be subject to Preventions of Significant Deterioration (PSD) and New Source Review 

(NSR) permitting thresholds for PM2.5 at the same level as PM1 0. EPA has not yet 

promulgated the PM2.5 NSR Implementation Rule, which will specify how PM2.5 emissions 

should be treated for PSD and major source NSR sources. Upon promulgation, the 

Commission intends to incorporate those changes into Regulation 3 as well. 

Regulation 3 also was revised in 2008 to address ozone formation in the Denver Metro 

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Colorado 110 SIP Elements 

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Area/North Front Range Ozone nonattainment area. Specifically, the Commission adopted 

revisions to control and reduce ozone precursor emissions. The revisions are part of the 

federally-enforceable SIP and help Colorado make progress toward eventual compliance with 

the 2008 ozone NAAQS set at 0.075 ppm. 

~ Regulation 4, Woodburning Controls-- Regulation 4 requires that new woodstove and fireplace 

inserts meet the federal certification requirements in specified areas of Colorado. 

~ Regulation 7, Volatile Organic Compounds Control -- Regulation 7 controls the emissions of 

volatile organic compounds, primarily in the Denver-metro area. It sets standards and mandates 

controls for specific types of volatile organic compound sources. In 2008 Regulation 7 was 

revised to increase control requirements for oil and gas condensate tanks, glycol dehydrators and 

reciprocating internal combustion engines. These revisions were made as part of the state's 

Ozone State Implementation Plan 

~ Regulation 11, Motor Vehicle Inspection -- Regulation 11 requires automobile emission 

inspection and maintenance programs to be implemented in specified areas of the state for 

gasoline powered on-road vehicles. These programs apply to businesses, industry, and the 

general public. In addition, the State's Automobile Inspection and Readjustment (AIR) 

program's purpose is to reduce motor vehicle related pollution through the inspection and 

emissions related repair of automobiles. The program, as defined in Regulation 11, works in 

specific areas of the State of Colorado and requires motor vehicles to meet emission standards 

through periodic inspection and, as necessary, repair. 

~ Regulation 16, Street Sanding and Sweeping -- Regulation 16 sets specification standards for 

street sanding material and street sweeping practices in the Automobile Inspection and 

Readjustment program area and Denver-metro particulate attainment/maintenance area. 

~ Common Provisions Regulation -- The Colorado Air Pollution Control Division may require 

owners and operators of stationary air pollution sources to install, maintain, and use 

instrumentation to monitor and record emission data as a basis for periodic reports to the 

Division under the provisions of the Colorado Air Quality Control Commission Common 

Provisions regulation. 

Section 110 (a)(2)(D)- Interstate Transport 

For interstate transport, the State's SIP needs to contain four provisions to ensure that Colorado 

emissions and pollutants do not: 

• significantly contribute to nonattainment in another State; 

• interfere with maintenance of the NAAQS by another state; 

• interfere with another State's measures to prevent significant deterioration of air quality; 

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and 

• interfere with another State's measures to protect visibility. 

Colorado has addressed federal interstate transport requirements for the 1997 ozone and PM2.5 

NAAQS with an interstate transport SIP revision submitted to EPA March 31, 2010. With regards 

to the 2006 PM2.5 standard, Colorado commits to prepare the appropriate demonstration 

showing that Colorado is complying with the significant contributions to nonattainment and the 

interference with maintenance provisions. Such a demonstration will be brought to the Colorado 

Air Quality Control Commission in 201 0 for submittal to EPA in 2011. 

For prevention of significant deterioration and visibility, Colorado's March 31, 2010 submittal 

addressed these portions of interstate transport for 1997 ozone and PM2.5 NAAQS as well as the 

2006 PM2.5 NAAQS, which is summarized below: 

For PSD with regard to PM2.5, in adopting revisions to Regulation Number 3 on February 21, 

2008, it was noted that a final implementation rule on PM2.5 has not been issued and the 

permitting thresholds were the same as PM10 emissions. This language in the Statement of Basis 

and Purpose of this revision demonstrates Colorado's commitment to apply the PM10 surrogate 

for PM2.5 practice (see Basis and Purpose 1.0.0., February 21, 2008). 

Thus, the implementation of Colorado's PSD and NNSR permitting program prevents significant 

deterioration in neighboring states and thereby satisfies section 110(a)(2)(D)(i)(II) ofthe CAA. 

Colorado's permitting program requires that demonstrations be made for all areas that are 

potentially impacted by emission from a proposed major source or modification. A PSD permit 

may not be issued unless the new or modified source demonstrates that emissions from the 

construction or operation of the facility will not cause or contribute to air pollution in any area 

that exceeds any NAAQS. 

A NNSR permit may not be issued unless the source shows it has obtained sufficient emissions 

reductions to offset increases in emissions of the pollutants for which an area is in nonattainment, 

consistent with reasonable further progress toward attainment. 

Colorado further confirms that major sources of PM 2.5 are subject to PSD and NNSR 

permitting programs implemented in accordance with EPA's interim guidance calling for use of 

PM 10 as a surrogate for PM 2.5. See Regulation Number 3, Part A Sections I.B.6 and I.B.16 

and Part B, Sections II.D.2 and II.D.3. 

Colorado implements a transitional program satisfying 40 CFR 51.166 by expressly identifying 

PM 2.5 and PM 10 as pollutants. Colorado is not including additional measures to prevent 

pollution in excess of increments until EPA has defined PSD increments for PM 2.5. 

Regarding visibility for PM2.5, Colorado's visibility protection program contains adequate 

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provisions that are either in the SIP or submitted for inclusion into the SIP to prohibit any source 

or other type of emission activity in the state from emitting air pollutants in amounts that will 

interfere with measures required to be included in the applicable implementation plan of another 

state to protect visibility. Colorado's implementation plan also adheres to the directions set forth 

in EPA's applicable guidance interpreting this section of the Clean Air Act. 

The plan submitted to EPA on March 31, 201 0 demonstrates that there is a significant downward 

trend in Colorado's visibility impairing emissions, visibility in surrounding Mandatory Class I 

Areas is improving over time, and regional modeling indicates that Colorado has an extremely 

small contribution to out-of-state haze. Thus, air pollution sources and other types of emission 

activity within the State of Colorado do not interfere with measures required to be included in the 

applicable implementation plan of another state to protect visibility. 

Clean Air Act Section 110 (a)(2)(E)- Adequate Resources, State Boards, and Authority 

Personnel, Funding, and Authority 

There are no state or federal provisions prohibiting the implementation of any provision of the 

Colorado SIP. In general, Colorado provides the necessary assurances that funding, personnel, and 

authority exist an.d that the State of Colorado has responsibility for implementing local provisions. 

The Air Quality Control Commission (AQCC) adopted all of the regulatory provisions in the SIP 

pursuant to authority delegated to it by statute. The AQCC's general authority to adopt the rules and 

regulations necessary to implement the SIP is set out in the Colorado Air Pollution Prevention and 

Control Act Section 25-7-105 ofthe Colorado Revised Statutes (C.R.S.). The general authority for 

the Air Pollution Control Division to administer and enforce the program is set out at 25-7-111, 

C.R.S .. Additional authority to regulate air pollution and implement provisions in the SIP is set out 

elsewhere in the Colorado Air Pollution Prevention and Control Act, Article 7 of Title 25. In 

addition, the AQCC and the Division have the authority delegated to them in Sections 42-4-301 to 

42-4-316, C.R.S. (concerning motor vehicle emissions) and 42-4-414 (concerning emissions from 

diesel-powered vehicles). 

The AQCC's authority includes the authority to regulate particulate emissions, regardless of size 

(C.R.S. Section 25-7-109 (2)(b)). 

The Colorado Air Pollution Control Division has staff and an annual budget to operate its six 

programs (Stationary Sources, Mobile Sources, Indoor Air, Technical Services, Planning and 

Policy, Administrative Services). As of June 30, 2009, the Division employed 159 people and had a 

budget of $19.7 million for fiscal year 2009. 

Of the total budget, 17 percent was derived from federal grants, 32 percent from mobile source fees, 

4 7 percent from stationary source fees, and 4 percent from other cash sources. 

State Boards 

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Section 128 of the CAA indicates Colorado's State Implementation Plan must contain requirements 

that anybody that approves permits or enforcement orders under the CAA must have a majority of 

members who represent the public interest and do not derive any significant portion of their income 

from persons subject to permits or enforcement orders. 

The AQCC's Procedural Rules, section 1.11.0 state that "The Commission shall have at least a 

majority of members who represent the public interest and do not derive a significant portion of 

their income from persons subject to permits or enforcement orders under this article or under 

the federal act. The members of the Commission shall disclose any potential conflicts of interest 

that arise during their terms of membership to the other Commissioners in a public meeting of 

the Commission." 

Relationships with other agencies responsible for carrying out State activities 

The Colorado Air Pollution Control Division contracts with local governments in two distinct ways: 

1. Colorado grants monies to local health departments to endow them as agents of the State to 

provide inspections of some local stationary sources, asbestos abatement jobs, and CFC 

sources. Some local health departments also operate gaseous and particulate monitors under 

contract for the state. These efforts must comply with federal and state regulations. 

2. Colorado grants monies to local governments to help pay for their support of SIP elements 

via public and private partnerships, education and informational campaigns. Most of these 

agencies create their own work plan that consists of programs they believe will help enhance 

air quality in their communities in accordance with general SIP directives. 

Colorado has adopted specific regulations for local attainment/maintenance areas to assure these 

areas meet requirements of the state SIP. These regulations include The Colorado Air Quality 

Control Commission SIP-specific regulations, 5 CCR 1001-20. These regulations provide the 

necessary authority for the Colorado Air Pollution Control Division to adequately enforce the 

provisions ofthe SIP elements in local attainment/maintenance areas. 

Clean Air Act Section 110 (a)(2)(F)- Stationary Source Monitoring System 

Colorado Air Quality Control Commission Regulations 1, 3, and 6 address the issue of stationary 

source monitoring. Colorado Regulation 1 sets forth emission limitations, equipment requirements 

and work practices (abatement and control measures) intended to control the emissions of 

particulates, smoke, and sulfur dioxides from new and existing stationary sources. Colorado 

Regulation 3 requires stationary sources to report their emissions on a regular basis through Air 

Pollution Emission Notices (APENs). This air pollutant inventory program is described in the 

Colorado Pollution Prevention and Control Act Section 25-7-114.1 (C.R.S.) and in Colorado 

Regulation 3, Part LVIII that allows for monitoring and record keeping of air pollutants. Colorado 

Regulation 6 sets standards of performance for new stationary sources in the state and establishes 

monitoring system requirements. 

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The Colorado Air Pollution Control Division may require owners and operators of stationary air 

pollution sources to install, maintain, and use instrumentation to monitor and record emission data 

as a basis for periodic reports to the Division under the provisions of the Colorado Air Quality 

Control Commission Common Provisions regulation. 

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Section 110 (a)(2)(G) - Emergency Power 

The State has the authority to implement emergency powers similar to Section 303 of the Clean Air 

Act First, the EPA-approved "Denver Emergency Episode Plan" addresses ozone, particulate 

matter (PM 1 0), and carbon monoxide for the Denver metro region and requires the State to 

implement protective measures when air quality exceeds defined thresholds. Additionally, the 

Colorado Pollution Prevention and Control Act Sections 25-7-112 and 25-7-113, which have 

various sections similar to 42 USC 7603, generally describe Colorado's authority regarding 

Emergency Episodes. For example, 25-7-112 (2) provides the Governor the authority to implement 

emergency provisions through an order to the Colorado Air Pollution Control Division. 

As described in EPA's September 25,2009 guidance, areas that have had a PM2.5 exceedance 

greater than140.4 ug/m3 should have an emergency episode plan. If no such concentration was 

recorded since 2006, the state can rely on its general emergency authorities. Colorado has never 

recorded such a PM2.5 level and thus an emergency episode plan for PM2.5 is not necessary. 

Never-the-less, the State hereby certifies that it has the appropriate emergency powers to address 

PM2.5 episodes, as described above. 

Additionally, the State implements EPA's air quality index system and typically issues alerts and 

advisories to the public when any pollutant is expected to or exceeds an AQI index value of 100. If 

PM2.5 concentrations are expected to or actually exceed EPA's recommended index value 

thresholds of201 (alert), 301 (warning), 350.5 (significant harm), or 401 (emergency), the State can 

invoke emergency powers. 

Section 110 (a)(2)(H)- Provisions for SIP Revisions Due to NAAQS Changes 

or Findings of Inadequacies 

The State of Colorado has the ability and authority to address and revise the State Implementation 

Plan due to changes in the National Ambient Air Quality Standards (NAAQS) or due to findings of 

inadequacies. 

The Colorado Air Quality Control Commission has the authority and the duty to adopt and revise a 

State Implementation Plan as necessary to comply with the federal requirements. Colorado Air 

Pollution Prevention and Control Act Section 25-7-105 (1)(a)(I) (C.R.S.) directs the Colorado Air 

Quality Control Commission to promulgate rules and regulations as related to a comprehensive 

State Implementation Plan which will assure attainment and maintenance of the NAAQS and which 

will prevent significant deterioration of air quality in the State of Colorado. 

Colorado Air Pollution Prevention and Control Act Section 25-7-109 (C.R.S.) also gives the 

Colorado Air Quality Control Commission the authority to promulgate emission control regulations. 

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Section 110 (a)(2)(1)- Provisions for Nonattainment Areas to Meet the Applicable 

Requirements of Part D 

While the EPA sectionllO SIP guidance dated October 2, 2007 excludes the need for 

determinations under Part I, Colorado meets the applicable requirements for SIPS and SIP 

revisions in nonattainment areas as explained above under part D. 

Section 110 (a)(2)(J)- Consultation 

Engineering and meteorological consultation is provided by the State to local agencies. The State 

assists local agencies in planning air management programs for their respective areas. The Colorado 

Air Quality Control Commission holds public meetings and hearings on all State Implementation 

Plan revisions in accordance with the Air Quality Control Commission Procedural Rules. Public 

comment is solicited and accepted at Colorado Air Quality Control Commission meetings and 

hearings. 

Colorado's Transportation Conformity Rule, Regulation 10, specifies consultation procedures for 

SIP revisions in Section IV.F. 

Also, as part of the State of Colorado's Visibility SIP, the Colorado Air Pollution Control Division 

consults with the Federal Land Managers and other states as necessary and required. 

Section 110 (a)(2)(J)- Public Notification 

Colorado notifies the public of instances or of areas in which any national primary ambient air 

quality standard is exceeded. Included in this notification are public awareness announcements 

regarding health hazards and manners in which the public can participate in regulatory and other 

efforts to improve Colorado's air quality. Not only does the State provide after-the-fact information 

about readings in excess of the NAAQS, the Denver PM10 SIP provides for advance warnings to the 

public that the NAAQS may be exceeded whenever meteorological conditions make it possible or 

likely for ambient concentrations to exceed the NAAQS. 

The Colorado Air Pollution Control Division prepares a daily public notification in the form of 

an Air Pollution Advisory for a nine-county Denver-Boulder metropolitan and North Front 

Range area and the communities of Fort Collins, Greeley and Colorado Springs. The advisory is 

posted on the Division website and includes details ofthe day's air quality and visibility, a 

forecast of the coming day's air quality, residential burning restrictions and voluntary motor 

vehicle driving reduction requests during the winter high pollution season. The advisory includes 

links to an open burning forecast and other important information such as the day's Air Quality 

Index, the health effects of specific pollutants and measures that can be taken by the public to 

reduce exposure. While not part of Colorado's SIP, the advisories are part of an ongoing 

commitment by the State to inform and educate citizens about air quality. 

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Other Colorado communities also maintain and operate daily air quality forecasts, including 

Mesa County on the Western Slope and El Paso County in the Colorado Springs area. 

The State has developed Natural Events Action Plans that include public notification and education 

elements. While not a formal part of the state SIP, the plans include provisions to notify the public 

about actions to take during imminent blowing dust and wildfire events that could lead to high 

levels of particulate matter. 

Clean Air Act Section 110 (a)(2)(J)- Prevention of Significant Deterioration and Visibility 

Protection 

Prevention of Significant Deterioration 

Colorado Air Quality Control Commission Regulation 3 (Stationary Source Permitting and Air 

Pollution Emission Notice Requirements), Regulation 6 (Standards of Performance for New 

Stationary Sources) and Colorado's Long Term Strategy for Visibility Protection adequately 

address Prevention of Significant Deterioration and Visibility Protection. For example, new major 

stationary sources or major modifications are restricted in their emissions in order to protect the 

PSD increment under Colorado Air Quality Control Commission Regulation 3. Prevention of 

Significant Deterioration and visibility analyses are also required by New Source Review 

regulations of Colorado. Colorado is required to review new major stationary sources and major 

modifications prior to construction to assess potential impacts on visibility in any Class I Area. 

Colorado Air Quality Control Commission Regulation 3.XI.E, "New Source Review" (Appendix 

D) describes the applicant's demonstration that the proposed source will not have an adverse effect 

on visibility in Class I Areas. 

Visibility 

For PM2.5, Colorado's visibility protection program contains adequate provisions that are either 

in the SIP or submitted for inclusion into the SIP to prohibit any source or other type of emission 

activity in the state from emitting air pollutants in amounts that will interfere with measures 

required to be included in the applicable implementation plan of another state to protect 

visibility. Colorado's implementation plan also adheres to the directions set forth in EPA's 

applicable guidance interpreting this section of the Clean Air Act. 

The plan submitted to EPA on March 31, 201 0 demonstrates that there is a significant downward 

trend in Colorado's visibility impairing emissions, visibility in surrounding Mandatory Class I 

Areas is improving over time, and regional modeling indicates that Colorado has an extremely 

small contribution to out-of-state haze. Thus, air pollution sources and other types of emission 

activity within the State of Colorado do not interfere with measures required to be included in the 

applicable implementation plan of another state to protect visibility. 

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Clean Air Act Section 110 (a)(2)(K) - Air Quality Modeling and Data Handling 

Colorado has the authority and resources to model for criteria pollutants, including PM2.s. Air 

quality modeling is done for SIP revisions and for transportation conformity. Colorado Regulation 3 

(Stationary Source Permitting and Air Pollution Emission Notice Requirements) requires stationary 

sources to predict the effect of air pollutants in attainment areas. Regulation 3 also details the State 

of Colorado's program regarding permitting as related to air quality modeling and data handling in 

predicting the effect of emissions of a pollutant with an established NAAQS. Regulatory 

requirements for Air Quality Related Values as related to modeling are described within Colorado 

Regulation 3, Part B subsection X and XI. A permit modification for purposes of the acid rain 

portion of a permit are governed by regulations promulgated under Title N of the federal act, found 

in 40 CFR Part 72 as described under Colorado Regulation 3, Part C, subsection X.K. 

The Modeling, Meteorology, and Emission Inventory Unit within the Colorado Air Pollution 

Control Division performs and reviews air quality impact analyses for a variety of programs, 

including state implementation plan revisions, transportation conformity determination, stationary 

source permitting, environmental impact statements, and hazardous waste site studies. The analyses 

include modeling, meteorological analysis, and emission inventory development for mobile sources 

and area stationary sources such as woodburning. The unit also performs air quality forecasting for 

the Denver-area High Pollution Season, open burning, and for special air quality studies. Additional 

information regarding these programs and authority is provided below. Some of these programs are 

found in the SIP. For example, both Colorado Air Quality Control Commission Regulation 4 

(Woodburning) and the Denver PM to SIP address State air quality modeling programs. 

PSD and Increment Consumption - Colorado's PSD program includes a requirement that the State 

periodically assess the adequacy of its plan to prevent significant deterioration of air quality. This is 

presented in Regulation 3, Part B, Section VII. In addition, Regulation 3, Part A, Section VIII-

"Technical Modeling and Monitoring Requirements" states that all estimates of ambient 

concentrations required under Regulation 3 shall be based on the applicable air quality models, data 

bases, and other requirements generally approved by EPA and specifically approved by the 

Division. 

State Implementation Plan (SIP) Development - Modeling is performed in the development and 

revision of State Implementation Plans, as needed, to ensure that specific areas of the state will 

maintain or re-attain compliance with the NAAQS in light of development and increased population 

and traffic. 

Permits- The primary Colorado regulation for air quality permits is Colorado Air Quality Control 

Commission Regulation No. 3. Certain new/modified air pollution sources are subject to the 

regulatory modeling requirements in Regulation 3. Regulation 3, Part A, subsection VIII describes 

Colorado's technical modeling and monitoring requirements. Modeling is often required to obtain a 

construction permit. While modeling is not required to obtain an operating permit, it may be 

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required if the operating permit is modified (in Regulation 3, Part C, subsection X- Minor Permit 

Modification Procedures). Operating permits may also be subject to modeling if the application is 

for a combined construction/operating permit (in Regulation 3, Part C, subsection III.C.l2.d). 

Clean Air Act Section 110 (a)(2)(L) -Permitting Fees 

The State of Colorado requires the owner or operator of a major stationary source to pay the 

Colorado Air Pollution Control Division any fee necessary to cover the reasonable costs of 

reviewing and acting upon any permit application. The collection of fees is described in Colorado 

Air Quality Control Commission Regulation 3. Specifically, Regulation 3, Part A. VI describes how 

each applicant required to obtain a permit must pay a fee, including the cost of permit review and 

relevant actions. Also, stationary source owners or operators must pay an annual fee based on total 

emissions. The funds are used by the State to administer programs for the control of air pollution 

from stationary sources. 

Clean Air Act Section 110 (a)(2)(M)- Consultation/Participation by Affected Local Entities 

Colorado Air Quality Control Commission Regulation 10, "Transportation Conformity," defines the 

criteria the Colorado Air Quality Control Commission uses for transportation conformity 

detc1minations to develop SIP revisions in non-attainment areas. Interagency consultation 

requirements are detailed in Reg. 10, and meet the federal requirements under 40 CFR 51.3 90, as 

published at 62 Fed. Reg. 158 (August 15, 1997). Colorado Air Quality Control Commission 

Regulation 3 also provides for consultation and participation by local entities. Local governments 

receive notice and have the opportunity to comment on and participate in construction permit 

review procedures and operating permit application procedures. 

The Colorado Air Quality Control Commission holds a public hearing before adopting any 

regulatory revisions to the SIP. Local political subdivisions may participate in the hearing. 

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