# STATE OF COLORADO

John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH, Executive Director and Chief Medical Officer COLORADO AIR QUALITY CONTROL COMMISSION http://www.cdphe.state.co.us 4300 Cherry Creek Drive South OED-OLRA-A5 Denver, Colorado 80246-1530 Phone (303) 692-3100 Fax (303) 691-7702 TDD (303) 691-7700 Colorado Department of Public Health and Environment



### May 11, 2012

James B. Martin Regional Administrator US EPA Region VIII 1595 Wynkoop Street Denver, Colorado 80202

Dear Mr. Martin: The following action is submitted to EPA for final approval and incorporation into the Colorado State Implementation Plan (SIP) pursuant to 40 CFR Part 51, Appendix V, 2.1(a). One hard copy and a CD of the materials needed for your review of each action are included with this letter.

• Steamboat Springs PM10 Maintenance Plan and the Air Quality Standards, Designations and Emission Budgets Regulation — The revised plan includes updated PM 10 monitoring data showing ongoing compliance with the federal PM10 standard. Given the ongoing compliance, no new control strategies are included in the plan. Updated mobile source emission inventories and a revised emission budget utilized for transportation planning are included in the revised plan. We look forward to your timely review and approval of this request. The Office of the Colorado Air Quality Control Commission may submit any additional technical support documentation or information that you may need for review directly to the EPA.James B. Martin May 28, 2012 Page 2 of 2 

### Should there be any questions regarding these materials, please contact the Air Quality Control Commission Office at 303-692-3478. Thank you.

Sincerely,

Christopher E. Urbina, MD, MPH Executive Director and Chief Medical Officer Colorado Department of Public Health and Environment

cc. Martha Rudolph Mike Silverstein Mark Komp

# Air Quality Standards, Designations and Emission Budgets Regulation and Steamboat Springs PM1O Maintenance Plan

ADMINISTRATIVE MATERIALS

Copies of the following administrative materials are included in this submittal of revisions to the Air Quality Standards, Designations and Emission Budgets Regulation and Steamboat Springs PM 10 Maintenance Plan. Hearing held on December 15, 2011.

• Hearing Notice and Proposed Language as Published in the CCR and on the Commission Website 40 CFR Part 51 Appendix V 2.10

• Meeting Agenda where Public Hearing Occurred and Notice published in the 

### Legal Ads of the Denver Post 40 CFR Part 51 Appendix V 2.10

• Procedural Documents of the Commission (this includes the Agenda Item Control Sheet, the Memorandum of Notice, the Economic Impact Analysis)

• Parties Hearing Documents (this includes a list of the parties, the parties prehearing statements and rebuttal statements, and any orders by the Commission - - do not include all the attachments from the parties)

• EPA Comments 40 CFR Part 51 Appendix V 2.1(h)

• Public Comments 40 CFR Part 51 Appendix V 2.1(h)

• Adopted Statement of Basis, Specific Statutory Authority and Purpose

• Adopted Language by the Commission (in redline & footer noting adoption date and page numbers)

• State Implementation Plan Element Adopted by the Commission 40 CFR Part 51 Appendix V 2.1(d)

• Colorado Air Quality Control Commission Meeting Minutes 40 CFR Part 51 Appendix V 2.1(g)

• Legal Opinion of the Colorado State Attorney General 40 CFR Part 51 Appendix V 2.1(c) and (e)

• Regulation or Regulation Revisions as published in the Colorado Code of Regulations (this is the version that is published by Lexis Nexis) 40 CFR Part 51 Appendix V 2.1 (b)

# Hearing Notice and Proposed Language as Published in the CCR and on the Commission Website 40 CFR Part 51 Appendix V 2.10

Includes:

- Hearing Notice

- Proposed revisions to Air Quality Standards, Designations and Emission Budgets Regulation

- Proposed revisions to Steamboat Springs PM10 Maintenance Plan

- Proposed revisions to the Technical Support Document

# STATE OF COLORADO

John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH, Executive Director and Chief Medical Officer
Dedicated to protecting and improving the health and environment of the people of Colorado COLORADO AIR QUALITY CONTROL COMMISSION http://www.cdphe.state.co.us 4300 Cherry Creek Drive South, EDO-AQCC-A5 Denver, Colorado 80246-1530 Phone (303) 692-3100 Fax (303) 691-7702 TDD (303) 691-7700 vir



## * 'R 18 

## 76.
Colorado Department of Public Health and Environment


## NOTICE OF PUBLIC RULEMAKING HEARING BEFORE THE 

## COLORADO AIR QUALITY CONTROL COMMISSION Regarding proposed revisions to: 

## Steamboat Springs PM10 Maintenance Plan and the Air Quality 

## Standards, Designations and Emission Budgets Regulation

SUBJECT: The Air Quality Control Commission will hold a rulemaking hearing to consider a proposed revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Approval of the associated documents by both the City of Steamboat Springs and Routt County is anticipated by December 2011. Additionally, a change to the "Air Quality Standards — Air Quality Standards, Designations and Emission Budgets" regulation is proposed to update the PM10 emission budget for the Steamboat Springs area.
HEARING SCHEDULE: DATE: December 15, 2011 TIME: 9:00 AM PLACE: Colorado Department of Public Health & Environment 4300 Cherry Creek Drive South, Sabin Conference Room Denver, Colorado 80246 The hearing may be continued at such places and time as the Commission may announce. Interested

parties may contact the Commission Office at 303-692-3476 to confirm meeting dates and times.


### PUBLIC COMMENT: The Commission encourages all interested persons to provide their views either orally at the hearing or in writing prior to or at the hearing. The Commission especially solicits comments and analyses from persons whO will incur directly some cost or benefit from the proposed revisions. Public testimony will be taken as close to the start of the hearing as possible and during the hearing as necessary. Written and/or electronic submissions are requested, but not required to be submitted prior to the hearing to allow review prior to presentation at the hearing. Written and/or electronic submissions should be mailed to the Commission Office at least 14 days prior to the hearing.

Page 1 of 3

### PARTY STATUS: In order to obtain party status at the hearing, compliance with several requirements as defined in the Commissions Procedural Rules is necessary. A petition for party status must be filed by electronic mail with the Office of the Air Quality Control Commission no later than close of business on October 18, 2011. 

### The petition must: 1) identify the applicant; 2) provide the name, address, telephone and facsimile numbers, and email address of the applicants representative; and 3) briefly summarize what, if any, policy, factual, and legal issues the applicant has with the proposal(s) as of the time offiling the application. Electronically mailed copies must also be received, by this same date, by the Division staff person and the Assistant Attorneys General representing the Division and the Commission identified below. Any person may petition the Commission to file documents in paper copy format if they are unable for any reason to comply with the requirements of 1.3.8(2) of the Commission's Procedural Rules. An original and a specified number of paper copies must be filed in the Office of the Air Quality Control Commission, Colorado Department of Public Health and Environment, 4300 Cherry Creek Drive South, Denver, Colorado 80246. Individuals may also obtain party status through the submittal of an initial alternative rule to the proposed rule. The submittal of an alternative proposal must be accompanied by an electronic copy of the initial alternative proposed rule and all other associated documents as required by the Commission's procedural rules and must be filed by electronic mail with the Office of the Commission by the date specified for party status requests. Initial alternative rules must also be filed by electronic mail with the Division staff person and with each of the Assistant Attorneys General.

Theresa L. Martin Air Quality Control Commission 4300 Cherry Creek Drive South, EDO-AQCC-A5 Denver, CO 80246 Theresa.Martin@state.co.us Attorney for the Commission Andrea Gelfuso-Goetz Attorney General's Office 1525 Sherman Street, 7 th Floor Denver, CO 80203 Andrea.Goetz@state.co.us Christopher Dann Air Pollution Control Division 4300 Cherry Creek Drive South, APCD-Bl Denver, CO 80246 Christopher.Dann@state.co.us Attorneys for the Division Tom Roan Attorney General's Office 1525 Sherman Street, 7 th Floor Denver, CO 80203 Tom.Roan@state.co.us 

### Requests received beyond the above stated deadline shall only be considered upon a written motion for good cause shown. The Commission reserves the right to deny party status to anyone that does not comply with the Commission's procedural rules.

STATUS CONFERENCE: A status conference will be held October 25, 2011 at 10:00 

### a.m., at the Department of Public Health and Environment to ascertain and discuss the issues involved, and to ensure that parties are making all necessary efforts to discuss and resolve such issues prior to the submission of prehearing statements. Attendance at this status conference is mandatory for anyone who has requested party status.

Page 2 of 3

### PREHEARING CONFERENCE/PREHEARING STATEMENTS: Attendance at the prehearing conference is mandatory for all parties to this hearing. A prehearing conference will be held November 22, 2011 at 10:00 a.m. in the Commission Offices at 4300 Cherry Creek Drive South, Denver. All parties must submit by electronic mail a prehearing statement to the Commission Office by close of business November 15, 2011. In addition, electronically mailed copies of these documents must be delivered by that date to all persons who have requested party status. A copy of the prehearing statement must also be electronically mailed to the Division point of contact and each of the Assistant Attorneys General identified above by close of business November 15, 2011. Any revisions to the prehearing statement must be submitted to the Administrator of the Commission at the prehearing conference and by electronic mail to the Commission Office on the day of the prehearing conference. Any exhibit included in the prehearing statements will be electronically mailed to individual Commissioners for review prior to the hearing, provided the party files electronic copies of such exhibit. Rebuttals to the prehearing statement may be submitted to the Commission Office and all other parties by close of business November 29, 2011.
EXCEPTIONS TO FILE DOCUMENTS BY ELECTRONIC MAIL: The Commission's Procedural Rules provide for an exception to file documents by electronic mail. If granted an exception to electronic filing pursuant to the provisions of 1.3.8(3) of the Commission's Procedural Rules, the applicant for party status shall file an original and fifteen copies of the prehearing statement in the Office of the Air Quality Control Commission, and shall also deliver copies to each other party, applicant for party status, the Assistant AttorneysGeneral representing the Commission and Division, and the Division staff person for theproceedings, by electronic mail or as otherwise provided by the exception granted under Subsection 1.3.8(3), by that same day.
STATUTORY AUTHORITY FOR THE COMMISSION'S ACTIONS: The Commission promulgates this regulatory change pursuant to its authority under § 25-7- 105(1)(a)(I), C.R.S. to adopt a comprehensive state implementation plan that meets the requirements of the federal Clean Air Act. The rulemaking hearing will be conducted in accordance with Sections 24-4-103 and 25-7-110, 110.5 and 110.8 C.R.S., as applicable and amended, the Procedural Rules of the Commission and as otherwise stated in this notice. This list of statutory authority is not intended as an exhaustive list of the Commission's statutory authority to act in this matter. Dated this 16th day of September 2011 at Denver, Colorado Colorado Air Quality Control Commission

Michael Silverstein, Administrator

Page 3 of 3PM10: 2015 through 2021: 54 tons/day; 2022 and beyond: 55 tons/day. Nitrogen Oxides: 2015 through 2021: 70 tons/day; 2022 and beyond: 56 tons/day Trading provisions: Trading of PM10 for NOx, or NOx for PM10 to adjust emission budgets for purposes of demonstrating transportation conformity shall be allowed using the emission trading formula as follows: For trades necessary to increase a primary PM10 budget, 15.0 tons/day of NOx will be taken from the NOx budget to increase the primary PM10 budget by 1.0 tons/day, a ration of 15 to 1. For trades necessary to increase a NOx budget, 1.0 tons/day of primary PM10 will be taken from the primary PM10 budget to increase the NOx budget by 12.0 tons/day, a ratio of 1 to 12. Implementation of trading provisions: In the event the MPO cannot demonstrate consistency with the specific PM10 and NOx mobile source emission budgets, the trading provisions may be utilized only after the MPO has considered all reasonably available local control measures to meet the budgets. The MPO must demonstrate the need for trading through the usual consultation procedures for state implementation plan development delineated in Section IV (F) of AQCC Regulation Number 10, Criteria for Analysis of Conformity. If trading is utilized, the MPO shall include the following information in the transportation conformity determination: (1) The budget for primary PM10 and NOx for each required year of the conformity Denver Attainment/Maintenance Area (Modeling Domain) 

### DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT Air Quality Control Commission AIR QUALITY STANDARDS, DESIGNATIONS AND EMISSION BUDGETS
5 CCR 1001-14

V.A. Budgets V.A.1. The following Motor Vehicle Emission Budgets shall be utilized to assess the conformity of Transportation Plans, TIPs, and where appropriate, Projects, for the applicable periods and geographic areas indicated:determination, before trading is employed; (2) The portion of the original budget to be used to supplement a wanting budget, for each required year for the conformity determination; (3) The increased budget that results from trading, along with relevant calculations, and (4) the resulting primary PM10 and NOx budgets for each required year of the conformity demonstration. The MPO shall then compare projected emissions to the adjusted PM10 and NOx motor vehicle emission budgets to demonstrate conformity.

Denver Attainment Ozone Precursors (attainment/maintenance Maintenance Area area boundary) NOx 2002 and beyond 134 tpsd VOC 2002 and beyond 119 tpsd (tpsd = tons per summer day) Carbon Monoxide (attainment/maintenance area boundary) 2013 through 2020: 1625 tons/day; 2021 and beyond: 1600 tons/day.

Denver Metro Regional Emissions Budgets Area/North Front Range NOx: 122.9 tons/day 8-Hour Ozone VOCs: 109.2 tons/day Nonattainment Area Southern Sub-Regional Emissions Budgets NOx: 102.4 tons/day VOCs: 89.7 tons/day Northern Sub-Regional Emissions Budgets NOx: 20.5 tons/day VOCs: 19.5 tons/day

Aspen PM10 2023 and Beyond: 1,146 lbs./day Attainment/Maintenance Area Carlon City PM10 2020 and Beyond: 1,613 lbs./day Lamar (Modeling Area) PM10 2015 and Beyond: 7,534 lbs./day Pagosa Springs PM10 2021 and Beyond: 946 lbs./day (Modeling Area) Steamboat Springs

(Modeling Area) PM10_2015 and Beyond: 21,773 lbs./day PM102015 and Beyond: 21,773 lbs./day Telluride (Modeling Area) PM10 2021 and Beyond: 1,008 lbs./dayLongmont Attainment/Maintenance Area Carbon Monoxide 2010 through 2014: 43 tons/day 2015-2019: 43 tons/day 2020 and Beyond: 43 tons/day Colorado Springs Attainment/Maintenance Area Carbon Monoxide 2010 and Beyond: 531 tons/day

Ft. Collins Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 99 tons/day2010 through 2014: 98 tons/day2015 and Beyond: 94 tons/day Greeley Area Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 63 tons/day2010 through 2014: 62 tons/day2015 and Beyond: 60 tons/day

VIII. Statements of Basis, Specific Statutory Authority and Purpose VIII.BB. Steamboat Springs Adopted: December 15, 2011
Basis and Purpose The purpose of this amendment is to update the PM10 emission budget for the Steamboat Springs area in connection with the adoption of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area.
Specific Statutory Authority The Commission promulgates this regulatory change pursuant to its authority under § 25-7-105(1)(a)(I), C.R.S. to adopt a comprehensive state implementation plan that meets the requirements of the federal Clean Air Act.
Findings Pursuant to § 25-7-110.8 The mobile source emission budgets are based on EPA-approved methods for calculating PM10 emissions as required by federal regulations. All methodologies and information made available by interested parties have been considered. The emission budgets reduce the potential for air pollution bycapping emissions from mobile sources. In adopting this rule, the Commission chose the most costeffective alternative.

# Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

Colorado Department of Public Health and Environment

10-year Revision: In Draft, September 2011
Original Redesignation Request and Maintenance Plan adopted by:

• The U.S. Environmental Protection Agency, October 25, 2004 (effective November 24, 2004)

• Colorado Air Quality Control Commission, November 15, 2001

Revision Prepared By: Air Pollution Control Division Colorado Department of Public Health and Environment 4300 Cherry Creek Drive South Denver, Colorado 80246

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 1

### [Blank Page]

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 2

### TABLE OF CONTENTS

TABLE OF CONTENTS 3

SECTION 1: INTRODUCTION 4
A. BACKGROUND 5 1. PM10 National Ambient Air Quality Standard (NAAQS) 5 2. Health and Welfare Effects of PM10 5 3. Steamboat Springs Nonattainment Area Classification History 6 4. Steamboat Springs Attainment/Maintenance Area Boundary 6 Figure 1: Map of the Steamboat Springs Attainment/Maintenance Area 7 B. ORGANIZATIONS INVOLVED IN PREPARING/APPROVING PLAN 8

SECTION 2: PM10 ATTAINMENT HISTORY 9
A. MONITORING HISTORY 9 Table 1: Steamboat Springs PM10 Monitoring Record 9 B. DESIGN VALUE DETERMINATION 9

SECTION 3: STATE IMPLEMENTATION PLAN APPROVAL 11
A. 1995 SIP ELEMENT 11 B. 1996 SIP ELEMENT 11 C. PM10 MAINTENANCE PLAN 11 SECTION 4: PERMANENT AND ENFORCEABLE IMPROVEMENT IN AIR QUALITY 12

A. OVERVIEW 12 B. CONTROL MEASURES 12 1. Woodburning Emission Controls 13 2. Street Sanding Controls 13 3. Street Sweeping Requirements 13 4. Control of Emissions from Stationary Sources 13 5. Federal Motor Vehicle Emission Control Program 14

SECTION 5: MAINTENANCE PLAN 15

A. REQUIREMENTS 15 B. EMISSION INVENTORIES 16 1. 2008 Base Year Emission Inventory 16 Table 2: 2008 PM10 Base Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 17 2. 2016 Interim Year Emission Inventory 17 Table 3: 2016 PM10 Interim Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 17 3. 2024 Maintenance Year Emission Inventory 18 Table 4: 2024 PM10 Maintenance Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 18 C. MAINTENANCE DEMONSTRATION 19 D. PM10 EMISSION BUDGET 20 E. MONITORING NETWORK/VERIFICATION OF CONTINUED ATTAINMENT 20 F. CONTINGENCY PLAN 20 1. Tracking 20 2. Trigger and Response 21 3. Potential Contingency Measure's 22 G. SUBSEQUENT MAINTENANCE PLAN REVISIONS 22

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 3

## SECTION 1: INTRODUCTION This document is the second PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. The U.S. Environmental Protection Agency (EPA) first approved a PM10 redesignation request and maintenance plan for the Steamboat Springs area on October 25, 2004 (69 FR 62210), which became effective on November 24, 2004. The redesignation request and maintenance plan was adopted by the Colorado Air Quality Control Commission on November 15, 2001. This second maintenance plan, as revised in 2011, revises the first maintenance plan adopted by the commission in 2001. The 2011 plan includes updated emission inventories and projections using the latest EPA-approved tools. This plan also revises the PM10 mobile source emission budget from 21,773 pounds per day in 2015 to 1,103 pounds per day in 2024 and beyond. The City of Steamboat Springs, Routt County, and the state of Colorado request continuation of "attainment/maintenance" status for the Steamboat Springs PM10 Attainment/Maintenance Area. The Steamboat Springs area originally was designated as nonattainment for the National Ambient Air Quality Standard (NAAQS) for particulate matter with an aerodynamic diameter of ten microns or less (PM10) in 1993 (effective January 20, 1994). The area presently is demonstrating attainment with the PM10 NAAQS. The Maintenance Plan section of this document has been updated and will demonstrate that the area will be able to maintain compliance with the NAAQS through the year 2024. The benefits of maintaining attainment/maintenance status include: 1. Areas that maintain attainment/maintenance status no longer carry the stigma associated with nonattainment of the NAAQS. 2. Attainment areas will not become "serious" nonattainment areas even if a violation of the NAAQS occurs in the future. This means that specific control measures can be applied to address a violation without going through a rigorous federal process, where serious areas must implement mandatory control measures and be subject to numerous administrative activities. 3. Prevention of Significant Deterioration (PSD) permitting requirements continue to replace New Source Review (NSR) permitting requirements for new and modified major stationary sources. These permitting requirements are important for large industrial facilities that currently are not located, nor likely to locate, in the Steamboat Springs area. This plan is designed to document and ensure continuing attainment and maintenance of the NAAQS for PM10 in the Steamboat Springs area. This document is intended to comply with requirements of the federal Clean Air Act (CAA), and with relevant procedures and policies of the U.S. Environmental Protection Agency (EPA).

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 4

### A. BACKGROUND

1. PM10 National Ambient Air Quality Standard (NAAQS) In 1971, the EPA set NAAQS for several air pollutants, including total suspended particulates (TSP), defined as particles with an aerodynamic diameter of less than 40 microns. In 1987, the EPA changed the TSP standards by setting NAAQS for PM10, defined as particles with an aerodynamic diameter of ten microns or less (PM10). The current PM10 NAAQS allow for a maximum 24-hour average concentration of 150 ug/m3. The 24-hour PM10 NAAQS may not be exceeded more than once per year on average over any three-year period. There are both primary and secondary air quality standards. The primary standards are set to protect human health with a margin of safety to protect the more sensitive persons in the population like the very young, elderly and the ill. Secondary standards are set to protect property, materials, aesthetic values and general welfare. For PM10, the national primary and secondary standards are the same. The numerical levels of the standards are subject to change, based on new scientific evidence summarized in air quality criteria documents. In 2006, the EPA revoked the annual PM10 standard but retained the 24-hour average of 150 ug/m3 (71 FR 61144) for both the primary and secondary NAAQS. In general, demonstrating attainment requires collecting representative air monitoring data and using approved measuring instruments and procedures, with adequate quality assurance and quality control. Air quality measurements in the Steamboat Springs area satisfy this requirement, as shown in Section 2 (Table 1 — Steamboat Springs PM10 Monitoring Record).



### 2. Health and Welfare Effects of PM10 Particulate matter is the term given to tiny particles of solid or semi-solid material suspended in the atmosphere. PM10 refers to a subset of particulate matter 10 micrometers in diameter and smaller. PM10 is inhalable. In the Steamboat Springs area, PM10 is created primarily from re-entrained road dust, carbon black (from automobile and diesel engines) and soot (from fireplaces and woodstoves). PM10 from these combustion sources contains a large percentage of elemental and organic carbon, which contributes to atmospheric haze and to health problems. Additional PM10 sources, to a lesser degree, include restaurant grills and aircraft. Epidemiological studies and laboratory studies of humans and animals indicate that particulate matter can be inhaled deeply into the respiratory system, resulting in aggravation of existing respiratory and heart diseases, damage to lung tissue, impairment of breathing and respiratory functions, alterations to the body's physical and immune system defenses, and even premature death. Many particles also are composed of compounds that are known or suspected human carcinogens. People

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 5

### most sensitive to particulate matter are the elderly, children, and those with chronic lung disease, cardiovascular disease, influenza, and asthma.

The welfare effects of particulate air pollution are widespread. Chemical and photochemical reactions involving the particles may occur in the air, or once they have been deposited on environmental media or structures. Such soiling and acid deposition cause visibility degradation, climate changes, and damage to crops, natural vegetation, water bodies, and aquatic life. In addition, sculpture and architecture may be damaged or destroyed by particulate soiling and acid deposition. 

## 3. Steamboat Springs Nonattainment Area Classification History Because of observed problems with air particles, monitoring for PM10 began in 1985. Based upon numerous exceedances of the 24-hour PM10 NAAQS, the Steamboat Springs area was designated by the EPA as a "moderate" nonattainment area in 1993 pursuant to section 107(d)(3)(B) of the Clean Air Act.


## 4. Steamboat Springs Attainment/Maintenance Area Boundary The boundary for the Steamboat Springs PM10 Attainment/Maintenance Area is defined as follows: On the East: 

### The Routt National Forest

On the South: 

### The southern border of sections 19, 20, 21, T4N, R84W of the 6 th P.M. and the southern border of sections 23, 24, T4N, R85W of the 6 th P.M. Beginning at the southwestern corner of section 23, T4N, R85W of the 6 th 

## P.M., north along the western border of sections 23, 14, 11, 

## T4N, R85W. Thence, along the ridge which bisects sections 35, 36, 25, 24, 13, 14, 11, 12, 1, T5N, R85W, and sections 36, 25, 24, T6N, R85W. Thence, heading northwest along the ridge which bisects sections 23, 15, 10, 9, 4, T6N, R85W of 6 th P.M. Thence heading northeast along the ridge which bisects sections 33, 34, 35, 36, 25 T7N, R85W and sections 30 and 19 of T7N, R84W. Thence, north along the N 1 /2 of the western edge of section 19, to the NW corner of section 18, T7N, R84W. On the West:

On the North: 

### The northern boundary of sections 16, 17, 18 T7N, R84W of the 6 th P.M. A map illustrating the area boundary is shown in Figure 1.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 6

### Steamboat Springs PM-10 Attainment Area

4474,1. 6 .41.mtleo

- 1 -



### Legend

1- Col oradoAirports08nei

* Point Sources CITY

* PM 10 Monitor --H

- + RAILLIN ES Major Roads
HIGHWAYS
Local Roads City of Steam boat Springs NAME 

## L ; Steamboat Springs Attainment Area

0 1.26 2.5

II I 5 Miles I 

## I I Figure 1: Map of the Steamboat Springs Attainment/Maintenance Area

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 7

### B. ORGANIZATIONS INVOLVED IN PREPARING/APPROVING PLAN Preparation of this revised maintenance plan was a cooperative effort of the City of Steamboat Springs, Routt County, and the Air Pollution Control Division (APCD) of the Colorado Department of Public Health and Environment. The EPA, through its regional office in Denver, provided policy advice and technical assistance, and is responsible for final approval of this revised maintenance plan.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 8

## SECTION 2: PM10 ATTAINMENT HISTORY

A. MONITORING HISTORY Monitoring for PM10 in Steamboat Springs began in 1985. Numerous exceedances of the 24-hour PM10 NAAQS were the basis for the Steamboat Springs area being designated as a "moderate" nonattainment area in 1993 (effective January 20, 1994). Table 1 lists the yearly maximum, yearly estimated exceedances and the 3-year average estimated exceedances for the Steamboat Springs monitoring site(s) for the 10-year period from 2001 through 2010. The state of Colorado maintains a PM10 monitor at 136 6 th Street in Steamboat Springs.



### Table 1: Steamboat Springs PM10 Monitoring Record

Year Maximum Concentration (ug/m 3 ) Yearly Estimated Exceedances 3-yr Average Estimated Exceedances 2001 100 0 0 2002 119 0 0 2003 149 0 0 2004 94 0 0 2005 86 0 0 2006 87 0 0 2007 99 0 0 2008 124 0 0 2009 83 0 0 2010 99


### B. DESIGN VALUE DETERMINATION The "design value" is the critical air quality value upon which the maintenance plan is based. The design value, and the conditions that occurred on the day which it was measured, are utilized to develop emission inventories and serve as a baseline for modeling ambient concentrations into the future. The selection of the design value used in this revised maintenance plan utilized the EPA's table look-up method from the EPA's "PM10 SIP Development Guideline" document.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 9

### Based on the number of samples collected during the 2008 - 2010 period (999), the third highest concentration is the design value, according to this guidance. The three highest concentrations measured during the period 2008 -2010 are as follows:

** 124 ug/m3 — February 18, 2008 ** 111 ug/m3 — February 20, 2008 ** 99 ug/m3 — February 3, 2010 Consequently, the design value used for this revised maintenance plan is 99 ug/m3.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 10

## SECTION 3: STATE IMPLEMENTATION PLAN APPROVAL The following presents a brief summary of the development and the approval of the Steamboat Springs PM10 Nonattainment State Implementation Plan (SIP) Element.



### A. 1995 SIP ELEMENT The first Steamboat Springs SIP Element was adopted by the Colorado Air Quality Control Commission (AQCC) in September 1995. The control measures included: 1) local restrictions on woodburning devices, 2) specifications for street sanding materials (no more than 1% fines allowed), and 3) street sweeping requirements on Lincoln Avenue (once after each sanding event). The plan also included monitoring data, emission inventories, and dispersion modeling which demonstrated attainment of the PM10 NAAQS by December 1999 and continuing through December 2002. The EPA did not approve this SIP Element at the request of the state due to revisions to control measures and modeling that occurred before EPA could take action on the plan.



### B. 1996 SIP ELEMENT A new Steamboat Springs PM10 SIP Element was adopted by the AQCC in October 1996. The control measures were revised to include: 1) local restrictions on woodburning devices, 2) specifications for street sanding materials (no more than 2% fines allowed), 3) street sweeping requirements on Lincoln Avenue (four times after each sanding event), and 4) street sand reductions of 10% on state highways. The plan also included revised monitoring data, emission inventories, and dispersion modeling which demonstrated attainment of the PM10 NAAQS by December 1999 and continuing through December 2002. In addition, contingency measures (additional street sweeping if the area violated the NAAQS and an emergency episode plan (suspension of open burning, voluntary wood and coal burning curtailment, and voluntary driving reductions if a NAAQS exceedance was expected) were adopted. This SIP Element was approved by the EPA on December 31, 1997 (62 FR 68188).



### C. PM10 MAINTENANCE PLAN The Colorado Air Quality Control Commission approved the Steamboat Springs PM10 Maintenance Plan on November 15, 2001. The EPA subsequently approved the plan on October 25, 2004, which became effective on November 24, 2004.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 11

## SECTION 4: PERMANENT AND ENFORCEABLE IMPROVEMENT IN AIR QUALITY

The state of Colorado must demonstrate, based on Section 107(d)(3)(E) of the Clean Air Act, that the improvement in air quality leading to attainment and continued compliance with the NAAQS is based on permanent and enforceable measures, and that the reductions are not the result of temporary reductions in emissions or unusually favorable meteorology.



### A. OVERVIEW It is reasonable to attribute the continued attainment of the PM10 NAAQS in the Steamboat Springs Attainment/Maintenance Area to emission reductions that are permanent and enforceable. These emission reductions are the result of local, state, and federal actions, not economic factors or unusual meteorology. Economic conditions are not responsible for improved ambient levels in the Steamboat Springs Attainment/Maintenance Area. It is assumed that growth in population and tax revenue are indicators of increased activities that cause increased PM10 emissions and the potential for elevated PM10 concentrations. Information obtained for the City of Steamboat Springs shows that, during the period 2000 through 2007, general sales and use revenues increased by 71.21 percent, while Routt County population increased by 16.85 percent over the same period. During this period, attainment of the PM10 NAAQS was demonstrated with no exceedances recorded. Favorable meteorology also is an unlikely reason. Although winter and spring meteorological conditions are highly variable in mountain settings, there is no evidence to suggest that meteorological conditions experienced in the 2000s have not been "typical" (though it is difficult to make concrete conclusions based on short-term meteorological records). Because there has not been a violation of the PM10 NAAQS in Steamboat Springs since 1996, the Air Pollution Control Division concludes that the good air quality in the Steamboat Springs area is the result of the implementation of emission reduction measures, not meteorological fluctuations.



### B. CONTROL MEASURES The following control measures resulted in the area's attainment of the PM10 NAAQS, and these measures should ensure continued maintenance of the PM10 NAAQS through the year 2024, which is the duration of the maintenance period.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 12

## 1. Woodburning Emission Controls The City of Steamboat Springs and Routt County have adopted local ordinances and resolutions that limit the number and types of woodburning devices in new construction in the Steamboat Springs area. Installation of new solid fuel burning devices is limited to one approved device for any building. These requirements were adopted locally in the late 1980s and early 1990s and included in state regulation in 1995 {Section VIII.E.of the "State Implementation Plan-Specific Regulatons for NonattainmentAttainment/Maintenance Areas (Local Elements)}. The rule was approved by the U.S. EPA in 1997. The requirements will remain part of state regulation and the federal State Implementation Plan (SIP). 

## 2. Street Sanding Controls There is a requirement that any user that applies street sanding materials in the Steamboat Springs Attainment/Maintenance Area must use materials containing less than two percent fines, except on U.S. Highway 40 from the junction of U.S. Highway 131 toward Rabbit Ears Pass. This requirement was adopted in 1996 and approved by the U.S. EPA in 1997, and is defined in detail in Section VIII.B. of the {State Implementation Plan-Specific Regulations for Nonattainment-Attainment/Maintenance Areas (Local Elements)}. The requirement will remain part of state regulation and the federal SIP. 

## 3. Street Sweeping Requirements There are street sweeping requirements for a defined section of Lincoln Avenue (Highway 40 in Steamboat Springs). Beginning with the effective date of the U.S. EPA's approval of the initial maintenance plan (November 24, 2004), street cleaning using vacuum sweepers or any other sweepers with equal efficiency must occur two times within the four-day period of the roadways becoming free and clear of snow and ice following each sanding deployment use. These requirements are defined in detail in Section VIII.D. of the {State Implementation Plan-Specific Regulations for Nonattainment-Attainment/Maintenance Areas (Local Elements)}. The requirements will remain part of state regulation and the federal SIP. 

## 4. Control of Emissions from Stationary Sources The state's comprehensive permit rules limit emissions from any new source that may, in the future, locate in the Steamboat Springs area. These rules include: 1) CAQCC Regulation No. 3, "Air Pollution Emission Notices, Construction Permits and Fees, Operating Permits, and Including the Prevention of Significant Deterioration," 2) the "Common Provisions" regulation, and 3) CAQCC Regulation No. 6, "standards for Performance for New Stationary Sources." The Common Provisions, and Parts A and B of CAQCC Regulation No. 3, already are included in the SIP. CAQCC Regulation No. 6 implements the federal standards of performance for new stationary sources. As was the case with the initial maintenance

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 13

### plan, this revised maintenance plan makes no changes to these regulations. This reference to CAQCC Regulation No. 6 shall not be construed to mean that this regulation is included in the SIP. Emissions of PM10 from new or modified major stationary sources are controlled under CAQCC Regulation No. 3's nonattainment area New Source Review (NSR) permitting requirements. The NSR provisions require all new and modified major stationary sources to apply emission control equipment that achieves the "lowest achievable emission rate" (LAER) and to obtain emission offsets from other stationary sources of PM10. The PSD requirements are a relaxation from the NSR requirements, as LAER becomes the less stringent "Best Available Control Technology" (BACT), and offsets are not required. The application of these provisions is possible, but not foreseen, in the Steamboat Springs area. It should be noted that significant additional controls at both the Tri-State Generation and Transmission Association's Craig Generating Station and the Xcel Energy Hayden Generating Station that are part of the Colorado Visibility and Regional Haze State Implementation Plan will be installed during the effective period of this revised plan.


### 5. Federal Motor Vehicle Emission Control Program The Federal Motor Vehicle Emission Control Program has reduced PM10 emissions through a continuing process of requiring diesel engine manufacturers to produce new vehicles that meet tighter and tighter emission standards. As older, higher-emitting diesel vehicles are replaced with newer vehicles, 

### PM10 emissions in the Steamboat Springs area will be reduced.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 14

## SECTION 5: MAINTENANCE PLAN
A. REQUIREMENTS Section 107(d)(3)(E) of the Clean Air Act (CAA) provides that, for an area to be redesignated to an attainment classification, the U.S. EPA must fully approve a maintenance plan which meets the requirements of CAA Section 175A. The maintenance plan will constitute a SIP revision and must provide for maintenance of the relevant NAAQS in the area for at least ten years after redesignation. The EPA first approved a PM10 redesignation request and maintenance plan for the Steamboat Springs area on October 25, 2004 (69 FR 62210), which became effective on November 24, 2004. An additional requirement (Section 175A(d)) is the submittal of a SIP revision eight years after the original redesignation request/maintenance plan is approved that provides for maintenance of the NAAQS for an additional ten years following the first ten-year period. The state of Colorado has satisfied this commitment by submitting this revised maintenance plan as required by the CAA and EPA requirements. Section 175A further states that the plan shall contain such additional control measures as necessary to ensure maintenance. All current nonattainment area control measures shall remain in place, except for the most stringent NSR stationary source permitting requirements (see Section 4.B.4.). This maintenance plan revision shall contain a contingency plan to ensure the prompt correction of any unforeseen violation of the PM10 NAAQS. Failure to maintain the NAAQS and triggering of the contingency plan will not necessitate a revision of the SIP Element, unless required by the EPA Administrator, as stated in CAA Section 175A(d). The provisions that are addressed in this maintenance plan revision include emission inventories (for a base year, an interim year and a maintenance year), a maintenance demonstration, an emission budget, an approved monitoring network, verification of continued attainment, and a contingency plan.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 15

### B. EMISSION INVENTORIES The emission inventories below include the 2008 base year, the 2016 interim year and the 2024 maintenance year. These inventories reflect the base and projected conditions in the Steamboat Springs Attainment/Maintenance Area, and account for the emission control measures that were adopted as part of the original redesignation request and the previous 10-year maintenance plan. Unlike the previous Steamboat Springs plan where the emission inventories were based on a grid system of the attainment/maintenance area, the updated emission inventories for 2008, 2016 and 2024 are based on a number of EPA-approved emission modeling methods that are detailed in the Technical Support Document. Consequently, there are significant differences between the emission inventories in the previous plan and this revised and updated PM10 maintenance plan.



### 1. 2008 Base Year Emission Inventory The 2008 Base Year Emission Inventory for the Steamboat Springs Attainment/Maintenance Area is presented below. This updated emission inventory incorporates the most current estimates for the following 10 source categories:

• Commercial Cooking

• Construction

• Fuel Combustion

• Highway 

### Vehicles

• Non-Road

• Paved/Unpaved Road Dust

• Point Sources • Railroad

• Structure Fires

• Woodburning
The mobile source inventory (paved/unpaved road dust and highway vehicles) has been updated to reflect the following:

• Latest traffic (VMT) estimates from the Colorado Department of Transportation

• Revised emission factors and methods for determining paved road emissions

• Road paving of unpaved roads that has occurred in the area

• Vehicle exhaust emissions based on most up-to-date fleet mix

All emission estimates were prepared by using EPA-approved methods and assigned to the area comprising the Steamboat Springs Attainment/Maintenance Area.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 16

### Table 2 presents the 2008 PM10 Base Year emission estimates for each source category in tons per year and pounds per average day.

Table 2: 2008 PM10 Base Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2008 PM10 [tons/year] 2008 PM10 [lbsiday] Commercial Cooking 2.92 16.6 Construction 640.58 3509.7 Fuel Combustion 1.46 8.6 Highway Vehicles 25.55 140.5 Non-Road 16.43 89.6 Point Sources 33.95 185.1 Railroad 0.73 3.6 Road Dust 121.18 663.4 Structure Fires 0.00 0.7 Woodburning 87.24 478.0 Totals: 930.02 5095.9

2. 2016 

### Interim Year Emission Inventory Table 3 presents the 2016 PM10 Interim Year emission estimates for each source category in tons per year and pounds per average day.

Table 3: 2016 PM10 Interim Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2016 PM10 [tons/year] 2016 PM10 [lbs/clay] Commercial Cooking 3.65 20.5 Construction 789.68 4326.4 Fuel Combustion 1.83 10.6 Highway Vehicles 31.94 175.1 Non-Road 12.60 68.6 Point Sources 41.80 228.2 Railroad 0.92 4.5 Road Dust 142.17 778.5 Structure Fires 0.19 0.85 Woodburning 107.50 589.3 Totals: 1131.87 6202.4

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 17

### 3. 2024 Maintenance Year Emission Inventory Table 4 presents the 2024 PM10 Maintenance Year emission estimates for each source category in tons per year and pounds per average day.

Table 4: 2024 PM10 Maintenance Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2024 PM10 [tons/year] 2024 PM10 [lbs/day] Commercial Cooking 4.38 24.4 Construction 938.78 5143.1 Fuel Combustion 2.19 12.6 Highway Vehicles 38.33 209.6 Non-Road 8.76 47.5 Point Sources 49.64 271.3 Railroad 1.10 5.3 Road Dust 163.16 893.6 Structure Fires 0.37 1.0 Woodburning 127.75 700.5 Totals: 1333.71 7308.8

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 18

### C. MAINTENANCE DEMONSTRATION This maintenance plan revision provides for continued maintenance of the 24-hour PM10 NAAQS through the year 2024, the 20-year period after the original redesignation request and maintenance plan was approved by the U.S. EPA in 2004. Because there have never been any exceedances of the annual PM10 NAAQS in Steamboat Springs, an analysis for maintenance of the annual standard was not prepared for the original redesignation request and maintenance plan. The EPA subsequently revoked the annual standard in 2006. A design day concentration of 99 ug/m3 has been selected as a conservative value that represents the third-highest 24-hour maximum PM10 value recorded in Steamboat Springs during 2008-2010. This 99 ug/m3 concentration occurred on February 3, 2010. No reduction for background values has been taken into account for the design day value, making the 99 ug/m3 a conservative estimate of PM10 ambient air concentrations in Steamboat Springs. The design value likely overstates the actual amount of PM10. The emission inventory data presented in this document is used to determine the growth in PM10 emissions from the 2008 base year to the 2024 maintenance year. The emission inventory shows an increase in PM10 from 5,095.9 pounds per day in 2008 to 7,308.8 pounds per day in 2024. This represents an increase of 43.4 percent in emissions: 7308.8/5095.9 = 1.434, or 43.4 percent. The design day concentration of 99 ug/m3 of PM10 is then increased 43.4 percent to "roll forward" to the 2024 attainment year. This roll-forward modeling results in a 2024 concentration of approximately 142 ug/m3: 99 ug/m3 x 1.434 = 142 ug/m3 Since 142 ug/m3 is below the 150 ug/m3 standard, maintenance is demonstrated through 2024.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 19

### D. PM10 EMISSION BUDGET Federal "transportation conformity" regulations provide for the use of mobile source emission budgets in making conformity determinations in the area. The emission budget serves as a ceiling on mobile source emissions that federally funded or approved transportation projects must comply or conform. This maintenance plan revision establishes a mobile source PM10 emission budget for the Steamboat Springs Attainment/Maintenance Area of 1,103 lbs/day for 2024 and beyond. This budget is the total of the 2024 mobile source PM10 emissions (see Section 5.B.3. above), which includes PM10 emissions from highways and paved/unpaved road dust. This budget has been adopted in the AQCC's "Air Quality Standards - Air Quality Standards, Designations and Emissions Budgets" regulation.



### E. MONITORING NETWORK/VERIFICATION OF CONTINUED ATTAINMENT The Air Pollution Control Division has monitored ambient PM10 concentrations in the Steamboat Springs area since 1985. The division has operated, and will continue to operate, the Steamboat Springs 

### PM10 monitoring network in full accordance with the federal provisions of 40 CFR Part 58 and the EPA-approved Colorado Monitoring SIP Element. The division also will analyze the monitoring data to verify continued attainment of the PM10 NAAQS. This information will provide the necessary information to determine whether the Steamboat Springs area continues to attain the PM10 NAAQS. Detailed information regarding the state's monitoring efforts and historical monitoring data can be found in Section 2 of this document.



### F. CONTINGENCY PLAN Section 175(A)(d) of the Clean Air Act requires that the maintenance plan contain contingency provisions to assure that the state will promptly correct any violation of the PM10 NAAQS that may occur after the redesignation of the area to attainment. The EPA's redesignation guidance notes that the state is not required to have fully adopted contingency measures that will take effect without further action by the state. However, the contingency plan should ensure that contingency measures are adopted expediently once the need is triggered. The primary elements of the contingency plan involve the tracking and triggering mechanisms to determine when contingency measures would be needed, and a process for implementing appropriate control measures.


## 1. Tracking The tracking plan for the Steamboat Springs area will consist of monitoring and analyzing PM10 concentrations. In accordance with 40 CFR Part 58, Colorado will continue to operate and maintain the Steamboat Springs PM10 monitoring network.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 20

### 2. Trigger and Response Triggering of the contingency plan does not automatically require a revision of the SIP nor is the area necessarily redesignated once again to nonattainment. Instead, the state normally will have an appropriate timeframe to correct the violation with implementation of one or more adopted contingency measures. In the event that violations continue to occur, additional contingency measures will be adopted until the violations are corrected. Upon notification of a PM10 NAAQS exceedance, the Air Pollution Control Division and local government staff in the Steamboat Springs area will develop appropriate contingency measure(s) intended to prevent or correct a violation of the PM10 standard. Information about historical exceedances of the standard, the meteorological conditions related to the recent exceedance(s), and the most recent estimates of growth and emissions will be reviewed. The possibility that an exceptional event occurred also will be evaluated (notification to the EPA and to the local governments in the Steamboat Springs area of any exceedance generally will occur within 30 days, but no later than 45 days). This process will be completed within six months of the exceedance notification. If a violation of the PM10 NAAQS has occurred, a public hearing process at the state and local level will begin. If the AQCC agrees that the implementation of local measures will prevent further exceedances or violations, the AQCC may endorse or approve of the local measures without adopting state requirements. If, however, the AQCC finds locally-adopted contingency measures to be inadequate, the AQCC will adopt state-enforceable measures as deemed necessary to prevent additional exceedances or violations. Contingency measures will be adopted and fully implemented within one year of a 

### PM1 0 NAAQS violation. Any state-enforceable measures will become part of another revised maintenance plan, submitted to the Colorado Legislature and the EPA for approval.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 21

### 3. Potential Contingency Measures The APCD and local government staff may choose one or more of the following contingency measures to recommend to local officials and the AQCC for consideration. Contingency measures will be selected that quickly bring the area back into compliance with the PM10 NAAQS and that specifically meet the needs of the Steamboat Springs area. It is likely that no federal or state monies will be available to fund the implementation of the selected contingency measure(s). Most, if not all, of the costs will be borne by local citizens and governments, local businesses, and state government agencies.

• Increased street sweeping requirements

• Road paving requirements

• More stringent street sand specifications

• Voluntary or mandatory woodburning curtailment

• Bans on all woodburning

• Expanded, mandatory use of alternative de-icers

• Re-establishing new source review permitting requirements for stationary sources

• Transportation control measures designed to reduce vehicle miles traveled

• Other emission control measures appropriate for the area based on the consideration of cost-effectiveness, PM10 emission reduction potential, economic and social considerations, or other factors that the state deems appropriate 

### G. SUBSEQUENT MAINTENANCE PLAN REVISIONS This revised maintenance plan provides for continued maintenance of the PM10 NAAQS for an additional ten years beyond the original ten-year period. Consequently, no further maintenance plan updates are anticipated.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 22Colorado Department of Public Health and Environment / Air Pollution Control Division



# Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

DRAFT Technical Support Document Emission Inventory



## DRAFT September 2011 Colorado Department of Public Health and Environment Air Pollution Control Division 4300 Cherry Creek Drive South Denver, Colorado 80246

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011Colorado Department of Public Health and Environment / Air Pollution Control Division



# Table of Contents

1. EMISSION INVENTORY METHODOLOGY 1 2. 2008 AND 2024 EMISSION INVENTORY SUMMARIES 4 3. REFERENCES 5



### ii Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011Colorado Department of Public Health and Environment / Air Pollution Control Division



## 1. Emission Inventory Methodology The Air Pollution Control Division (APCD) developed the 2008 and 2024 emission inventories in the "PM10 Maintenance Plan for Steamboat Springs" using U.S. Environmental Protection Agency (EPA) approved emissions modeling methods, including EPA's MOVES2010a model and local VMT data for on-road mobile source emissions, EPA's non-road model, local demographic information for area and off-road sources, and reported actual emissions for point sources. Estimates for future emissions are based on the above-mentioned tools and population estimates from the State Demographer. The inventory represents average daily winter emissions. The MOVES2010a and non-road model inputs represent these average daily winter conditions. Heating and wood burning emissions were apportioned from annual emission estimates by heating degree day data from the Western Regional Climate Center. Other source categories were apportioned from annual to daily by dividing by 365.

Highway mobile source emissions are from the EPA model MOVES2010a, an emission factor model for predicting gram per mile emissions of Hydrocarbons (HC), Carbon Monoxide (CO), Nitrogen Oxides (NOx), Carbon Dioxide (CO2), Particulate Matter (PM), and toxics from cars, trucks, and motorcycles under various conditions. Non-road source emissions are from the EPA Non-Road Model. This model includes the impact of future controls on non-road engines, which is used in equipment such as lawn and garden equipment and construction equipment. Area source emissions (including heating, construction, commercial cooking, etc.) are from the 2008 EPA National Emissions Inventory (NEI), grown to 2024 by population growth from data from the State. For more documentation for these categories, refer to the NEI documentation (EPA, 2010). Wood burning and road dust emissions were calculated using local data and EPA AP-42 emission factors. It should be noted that the previous emissions inventory was based on data from 1997. Emission factors and activity data have evolved since that time. The largest share of total emissions, both in 1997 and 2008 and beyond, is dust from paved roads. These emissions are a function of VMT, silt loading and empirically derived constants. The VMT's are nearly the same, a silt loading of about 10 grams per square meter was used in the 1997 inventory, while a silt loading of only 0.5 grams per square meter was used in this inventory. This results in an emission factor which is more than 20 times higher for paved road dust in 1997 than in the current inventory. The lower silt loading number used in the current inventory is more in line with current practices of using less sand for snow events, and quicker cleanup after the events. The MOVES2010A and Non-Road Models and the NEI report emissions for Pitkin County as a whole. Emissions were apportioned to the Attainment Area using geographical information system (GIS) techniques, using population, VMT and land area.

1 Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011

### Colorado Department of Public Health and Environment / Air Pollution Control Division

Under Air Quality Control Commission Regulation No. 3, the APCD requires any source that emits two tons per year or greater to submit an Air Pollutant Emission Notice (APEN) (APCD, 2008). This means that sources that emit less than two tons per year are not necessarily accounted for in an emissions inventory. The point source emissions for Steamboat Springs were obtained from this tracking system. The emission estimates are made using a variety of methodologies. Data from source-specific emission tests, or continuous emission monitors are preferable, but not always available. The EPA has developed a variety of emission factors to estimate emissions as well. Emission factors are frequently the best or only method available for estimating emissions.

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011

## Steamboat Springs PM-10 Attainment Area

Legend

- 

### 1 - ColoradoAlrports08nei 

# • Point Sources CITY



# * PM10 Monitor 4F--I- RAIL_UN ES Major Roads HIGHWAYS Local Roads City of Steamboat Springs 

### NA ME Steamboat Springs Attainment Area

0 1.25 2 5 5 Miles I I I I I I Colorado Department of Public Health and Environment / Air Pollution Control Division

Revised PM1 0 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011

### Colorado Department of Public Health and Environment / Air Pollution Control Division


## 2. 2008 and 2024 Emission Inventory Summaries This section presents the 2008 and 2024 emission inventories for the maintenance plan.

Table 1. PM10 Emission Inventories Based on 2008 NEI and Projected by Population (except as noted)

Steamboat Springs Attainment Area 2008 2024 Category PM10 t/d PM10 Pounds/d PM10 t/d PM10 Pounds/d Commercial Cooking 0.008 16.6 0.012 24.4 Construction 1.755 3,509.7 2.572 5,143.1 Fuel Combustion 0.004 8.6 0.006 12.6 Highway Vehicles* 0.070 140.5 0.105 209.6 Non-Road** 0.045 89.6 0.024 47.5 Railroad 0.002 3.6 0.003 5.3 Road_Dust*** 0.332 663.4 0.447 893.6 Structure Fires 0.000 0.7 0.001 1.0 Woodburning  0.239 478.0 0.350 700.5 Point Sources** *** 0.093 185.1 0.136 271.3 TOTAL 2.548 5,095.9 3.654 7,308.8

* Based on MOVES, CDOT VMT ** Based on NonRoad Model *** Based on Latest AP-42, CDOT VMT   Based on AP-42, Projected by Population as of 4/25/2011 data from State Demographer ** *** Based on APENS, Projected by Population as of 4/25/2011 data from State Demographer

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011 4

### Colorado Department of Public Health and Environment / Air Pollution Control Division



## 3. References
APCD, 2008. Air Quality Control Commission Regulation Number 3. Stationary Source Permitting and Air Pollutant Emission Notice Requirements. 5 CCR 1001-5. < 

### http://www.cdphe.state.co.us/regulations/airregs/1 001 03 stationarysourcepermitting.pdf > U.S. EPA, 2010. "2008 National Emissions Inventory Data & Documentation." < 

### http://www.epa.govittn/chief/net/2008inventory.html >

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Draft Technical Support Document - Emission Inventory August 30, 2011

# Meeting Agenda where Public Hearing Occurred and Notice published in the Legal Ads of the Denver Post 

# 40 CFR Part 51 Appendix V 2.10

# STATE OF COLORADO

John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH, Executive Director and Chief Medical Officer COLORADO AIR QUALITY CONTROL COMMISSION littp://www.cdphe.state.co.us
4300 Cherry Creek Drive South OED-OLRA-A5 Denver, Colorado 80246-1530 Phone (303) 692-3100 Fax (303) 691-7702 TDD (303) 691-7700 Colorado Department of Public Health and Environment 

# Notice of Meeting and Agenda Air Quality Control Commission
December 15, 2011 Colorado Department of Public Health & Environment 4300 Cherry Creek Drive South, Sabin Room Denver, Colorado



## 9:00 a.m.

Call to Order: Determination of a Quorum
Approval of Minutes: Review/Approval of the October 20, 2011 meeting minutes of the Air Quality Control Commission.

Public Comment:

RAQC Review: The public is invited to comment on any air pollution issue not on the agenda. The Commission will not take action on issues discussed under this item today; however, items may be scheduled for further discussion or action. Ken Lloyd of the Regional Air Quality Council will brief the Commission on updates from the RAQC and items that may be scheduled for further discussion.

CONSENT AGENDA 

### The Commission will vote on Item Numbers 1 through 4 as part of a Consent Agenda. Adoption of a Consent Agenda allows the Commission to consolidate voting on agenda items that do not need to be discussed individually and for which presentation of additional information is not required.REQUEST FOR PUBLIC HEARING 

### 1. Pikes Peak Area Council of Governments (PPACG) The Pikes Peak Area Council of Governments requests February 2012 hearing (or consent agenda ruling) regarding Conformity of its 2035 

### Moving Forward Regional Transportation Plan and 2012-2017 Transportation Improvement Program. The PPACG has made an affirmative conformity determination for its Plan and TIP, and seeks AQCC concurrence with the findings.

RULEMAKING HEARINGS 

### 2. Regulation Number 9: Smoke Management Distribution of Cost Update The Commission will consider revisions to Regulation Number 9 regarding a periodic update in each permittees recent emissions and permitting activity data. This data is used to determine the distribution of the cost of the smoke management program to each permittee.

3. PM2.5 Interstate Transport SIP The Commission will consider a proposed revision to the Interstate Transport State Implementation Plan (SIP) for the 2006 PM2.5 standard. This revision is a supplement to previously-approved chapters of the Interstate Transport SIP that the Commission approved in January 2010 and December 2008, which focused on the 1997 ozone and PM2.5 standards.

4. Steamboat Springs PM10 Maintenance Plan The Commission will consider a proposed SIP revision to the PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Approval of the associated documents by both the City of Steamboat Springs and Routt County is anticipated by December 2011. Additionally, a change to the "Air Quality Standards — Air Quality Standards, Designations and Emission Budgets" regulation is proposed to update the PM10 emission budget for the Steamboat Springs area.
TRADITIONAL AGENDA RULEMAKING HEARINGS 

### 5. Regulation Number 10 and Procedural Rules: Criteria for Conformity (20 minutes presentation, 20 minutes discussion) The Commission will consider streamlining the transportation conformity process by allowing the Colorado Air Pollution Control Division to provide concurrence with routine transportation conformity determinations without the need for a public hearing before the Colorado Air Quality Control Commission. This change to the conformity process is allowed for under federal law and will reduce the burden on the AQCC, the Division and transportation planning organizations, while ensuring that air quality requirements are met. The Commission will consider proposed revisions to the SIP, AQCC's Regulation Number 10 and the Procedural Rules.BRIEFINGS, DISCUSSIONS AND REPORTS 

### 6. Rocky Mountain National Park (20 minutes presentation, 20 minutes discussion) The Air Pollution Control Division, National Park Service, and Environmental Protection Agency are working together on the RMNP Initiative, a collaborative effort to reduce nitrogen deposition in Rocky Mountain National Park. The agencies will brief the AQCC on the progress of the tasks outlined in the Nitrogen Deposition Reduction Plan endorsed by the Commission in 2007 and the Contingency Plan adopted in 2010.

7. Monitoring Briefing (30 minutes presentation, 20 minutes discussion) The Division will brief the Commission on monitoring sites operated by the Division and others. The briefing will address EPA monitoring and siting requirements, why sites are located in certain places and not in others, what pollutants are monitored, and possibilities for additional monitoring. New monitoring requirements from EPA will also be addressed and the Division's current plans to meet those requirements.

8. HB09-1199: Colorado Healthy Forests and Vibrant Communities Act (40 minutes presentation, 20 minutes discussion) As a follow-up to the Commission's request from the March 2011 briefing, the Division will provide the Commission a status update regarding implementation of the recommendations from the HB09-1199 study. Additionally, the US Forest Service will be presenting a status update to the Commission on collaborative efforts with the Colorado Air Pollution Control Division regarding changes to the Colorado Smoke Management Program since the March 17, 2011 Commission hearing. Deputy Regional Forester Brian Ferebee will be the lead presenter and will be assisted by several agency technical specialists.

9. Commissioner Informational Items Commissioners will discuss among themselves activities that they have participated in over the past month that they believe other Commissioners and/or members of the public may be interested in hearing about.
10. Division Director's Report — Will Allison Monthly activities report
11. Attorney General's Report — Andrea Gelfuso-Goetz Update of any recent court actions on air quality issues
12. Administrator's Report — Mike Silverstein

• Review February agenda items

• Review of Action Items from today's Commission meeting Adjourn

3

## The Denver Newspaper Agency

PUBLISHER'S AFFIDAVIT City and County of Denver State of Colorado

The undersigned Jean Birch being first duly sworn under oath, states and affirms as follows: 1. He/she is the legal Advertising Reviewer of the Denver Newspaper Agency, publisher of The Denver Post and Your Hub. 2. The Denver Post and Your Hub are newspapers of general circulation that have been published continuously and without interruption for at least fifty-two weeks in Denver County and meet the legal requisites for a legal newspaper under Colo. Rev. Stat. 24-70-103. 3. The notice that is attached hereto is a true copy, published in The Denver Post on the following date(s):

Signa re

Subscribed and sworn to before me this 31 day of _ October , 2011.

Notary Public My commission expires September 14, 2013

(SEAL) Notice of Public end Rulemaking Hearings and Public Comment Hearings
PUBLISH 10/29/11
T i h n e gi C4r i a l igi , Air Quality Control Commission will hold the following rulernakDATE' December 15,2011 TIME 9:00 AM PLACE: Colorado Department of Public Health and Environment 4300 Cherry Creek Drive South - Sabin Conference Room Denver, CO 80246Notice of Rulemaking Hearing before the Colorado Air Quality Control Commission regarding Regulation Number 9 Smoke Management Distribution of Cost Update The Air Quality Control Commission wilt hold a rulemaking nearing to consider revisions to Regulation Number 9 regarding a periodic update in each Per

- mittees recent emissions and permitting activity data. This data is used to determine the distribution of the cost of the smoke management program to each eermittee.Notice of Rulemaking Hearing before the Colorado Air Quality Control Commission regarding Regulatfon Number 10 and the Procedural Rules Regulation The Air Quality Control Commission will hold a rulemaking hearing to consider streamlining the transportation conformity process by allowing the ColoradoAir Pollution Control Division to provide concurrence with routine transportation conformity determinations without She need for a public bearing before the Colorado Air Quality Control Commission. This change to the conformity process is allowed for under federal law and will reduce the burden on the AQCC, the Division and transportation planning organizationS, while ensuring that air Quality requirements are met. The Commission will consider Proposed revisions to the AQCC's Regulation Number 10 and she Procedural Rules, governing conformity determinations in Colota00. Notice of Rulemaking Hearing before the Colorado Air Quality Control Com-mission regarding Colorado State implementation Plan regarding the Interstate Transport Plan The Air Quality Control Commission will hold a rulemaking hearing to consider a proposed revision to the Interstate Transport State Implementation Plan(SIP) for the 2006 PM2.5 standard. This revision is a suoolernent to previously-approved chapters of the Interstate Transport SIP that the Commis- sion approved in January 2010 and December 2008, which focused on the 1997 ozone and PM2.5 standards.Notice of Rulemaking Hearing before the Colorado Air Quality Control Commission regarding Steamboat Springs PM10 Maintenance Plan and the Air Qualify Standards, Designation9 end Emission audgets Regulation The Air Quality Control Commission will hold,' rulemaking hearing to considera proposed revised PPM° Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Approval of the associated documents by both the City of Steamboat Springs and ROdIt County is anticipated by December 2011. Additionally, a change to the" Air Quality Standards - Air Quality Stan- dards, Designations and Emission Budgets" regulation is proposed to up- date the P M10 emission budget for the Steamboat Springs area.

# Procedural Documents of the Commission

- Agenda Item Control Sheet

- Memorandum of Notice

- Economic Impact Analysis (initial and final)

### COLORADO AIR QUALITY CONTROL COMMISSION AGENDA ITEM CONTROL SHEET

Item Title Proposed Revision to the PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Meeting date December 15, 2011

TYPES OF ACTION
NON-HEARING ACTIONS REQUEST FOR HEARING HEARING — Administrative X Public Rulemaking — Public Rulemaking Briefing Informational _ Informational _ Policy Area Designations

RECOMMENDED ACTION — Adoption X Approval _ Denial

MOTION X Required _ Attached _ Not applicable

STATUTORY AUTHORITY
General 25-7-105 Specific 25-7-106, -107, -109 -302

EPA SUBMITTAL
Is this issue considered a SIP revision? Yes X No

Which SIP? Steamboat Springs PM10 Date of EPA submission deadline: November 24, 2012

Agenda Item Control Sheet for the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 1ISSUE STATEMENT: The Air Pollution Control Division is requesting that the Colorado Air Quality Control Commission approve a proposed Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Both the City of Steamboat Springs and Routt County concur with the findings within the plan. The documentation shows that the Steamboat Springs area will continue to attain the PM10 National Ambient Air Quality Standard (NAAQS) through 2024, and has not violated the PM10 NAAQS during the past 10 years. No additional control measures are required for the Steamboat Springs area to maintain the standard. A change to the "Air Quality Standards — Air Quality Standards, Designations and Emission Budgets" regulation is needed, however, to update the PM10 emission budget for the Steamboat Springs area. By accounting for anticipated growth, it is projected that the Steamboat Springs area will demonstrate maintenance of the PM10 NAAQS through the year 2024 with a concentration of approximately 142 micrograms per cubic meter (the NAAQS is 150 ug/m 3 ). This revision will satisfy the federal requirement for showing attainment for the second ten-year period after redesignation to attainment/maintenance. No additional revisions of the Steamboat Springs maintenance plan are anticipated. If future changes in mobile source models or other unforeseen considerations raise potential issues with maintaining the PM10 standard, the State will address the need to revise the maintenance plan at that time.

Agenda Item Control Sheet for the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 2Program Manager

Division Director Date



### &iry 

### ci I Date ATTACHMENTS:

1 Revision to Air Quality Standards

2. Final Economic Impact Analysis

3. Final Statement of Basis and Purpose

4. Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

Technical Support Document/Emission Inventory for the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

SIGNATURES:

Preparer Date

-

Agenda Item Control Sheet for the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 3

### MEMORANDUM OF NOTICE

Date: August 30, 2011
To: Interested Parties Subject: Revision to the Colorado Air Quality Control Commission's "Air Quality Standards — Air Quality Standards, Designations and Emission Budgets" Regulation in Support of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

GENERAL DESCRIPTION The Air Pollution Control Division (Division) proposes this rulemaking package with the intent of revising the Colorado "Air Quality Standards — Air Quality Standards, Designations and Emission Budgets" regulation, specifically to revise the PMIO emission budget for the Steamboat Springs Attainment/Maintenance Area. Nothing in this rule change exceeds the minimum requirements of the federal act.
RULEMAKING PACKAGE Attachments to this memorandum provide details on the proposal as follows:

• Attachment A: The actual language of the proposed revision to the "Air Quality Standards" regulation;

• Attachment B: A statement describing the initial economic impact analysis of the proposed revision to the "Air Quality Standards" regulation;

• Attachment C: Draft Statement of Basis and Purpose

• Attachment D: The Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area; and

• Attachment E: Draft Technical Support Document — Emission Inventory
EXPLANATION OF THE PROPOSED RULES Adoption of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area and the above-mentioned Air Quality Standards regulation revision would establish a revised PM10 emission budget for the Steamboat Springs area. The Division requests approval and adoption of the revised maintenance plan and the proposed regulation revision as part of the State Implementation Plan (SIP).
MATERIALS TO BE INCORPORATED BY REFERENCE IN THE PROPOSED RULES There are no materials to be incorporated by reference in the proposed rule revision.

Memorandum of Notice for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment Maintenance Area August 30, 2011 Page 1

### PUBLIC MEETINGS You are invited to review these materials and present written or oral comments to the Division in accordance with the following: Date: (3rd week after publication of proposed rule in the Colorado Register) Time: 8:00 a.m. - 5:00 p.m. Place: 4300 Cherry Creek Drive South, Denver, CO 80246 Deadline for Submittal of Written Comments: November 1, 2011 Christopher Dann is lead Division staff for the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Following the close of the public comment period, Mr. Dann will prepare a Division Response to Public Comments that summarizes all public comments received, that discusses options for addressing the concerns, and makes recommendations from the Division for each issue. The Air Quality Control Commission (AQCC) will receive a copy of the Division Response to Public Comment and all written comments submitted to the Division. The AQCC will hold a public hearing on December 15, 2011. Interested parties may request meetings with Division staff three (3) weeks prior to the AQCC public hearing regarding this matter. To schedule a meeting, please contact Christopher Dann, who will make arrangements for a meeting regarding this proposed rulemaking. If you wish to be kept advised of these proceedings and/or receive a copy of the Division Response to Public Comments, you may request that your name be placed on the mailing list for this rulemaking proposal by contacting Christopher Dann at the following address: Christopher Dann Air Pollution Control Division 4300 Cherry Creek Drive South Denver, CO 80246-1530 Phone: (303) 692-3281 Fax: (303) 782-5493 E-mail: christopher.dann@state.co.us
BACKGROUND ON DEVELOPMENT OF THE PROPOSED RULES 

### What are the problems? The Air Pollution Control Division is submitting a 2011 Revised PM10 Maintenance Plan for the 

### Steamboat Springs Attainment/Maintenance Area as required by the U.S. EPA to assure attainment for a second 10-year period beyond the initial maintenance period. The initial 10- year maintenance period extended from the November 2004 date when EPA approved the initial redesignation request and the associated attainment/maintenance plan. The second 10-year period extends through 2024. As part of the 2011 revision, a new PM10 emission budget has been established for transportation conformity.

Memorandum of Notice for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment Maintenance Area August 30, 2011 Page 2

### How do the proposed rules help solve the problems? The proposed changes to the Air Quality Standards regulation assign an updated emission budget for transportation conformity using the latest emissions inventory data. This updated emission budget also is reflected in the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Nothing in these rule changes exceeds the minimum requirements of the federal act. RULES' EFFECTS ON PUBLIC, REGULATED COMMUNITY, AND OTHER AGENCIES The proposed emission budget reflects the latest estimate of emissions. The establishment of a budget will impact the planning of federally funded/approved highway plans and projects and could require the implementation of mitigation efforts in order to comply with the emissions budget cap. No direct costs to the public are anticipated by establishing the emission budget.
RELATIONSHIP TO FEDERAL AND ADJACENT STATE REQUIREMENTS 

### Federal Requirements: The revision to the emission budget conforms to federal regulation. 

### Adjacent State Requirements: The revision to the Air Quality Standards regulation is in conformance with the same federal requirements affecting attainment/maintenance areas in adjacent states.
IMPLEMENTATION OF THE RULES The revised emission budget will be implemented through conformity determinations made under the transportation conformity regulations. The SIP Specific Regulation contingency measures will cease upon AQCC adoption and EPA approval of this rule change. No additional contingency measures are necessary unless the area records a violation of the PM10 NAAQS in the future.
TIME CONSTRAINTS The proposed rule changes are to be completed in 2011 in order for the state to submit a Steamboat Springs SIP revision to the EPA in a timely manner to show attainment for the second ten-year term. In accordance with CAA 176A(b), it is required that a maintenance plan revision be submitted to the EPA within eight years after the original redesignation (which was on November 24, 2004) to address maintenance of the standard for a second ten-year period beyond redesignation. The purpose of this maintenance plan revision is to provide for maintenance of the PM10 standard for at least the additional ten years (through 2024) following the first ten-year period. There are no known specific time constraints except that this regulatory revision is directly associated with, and is a companion to, the maintenance plan update.

Memorandum of Notice for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment Maintenance Area August 30, 2011 Page 3

### RANGE OF REGULATORY ALTERNATIVES AND THE NO ANALYSIS No competing or alternative control measures were rejected when compiling this proposed 

### revision as no new controls are being proposed. By taking no action, there would not be a second ten-year maintenance plan for this area as 

### required by federal law. JUSTIFICATION FOR DIFFERING FROM FEDERAL REQUIREMENTS The proposed rules meet all requirements applicable to the area as required by federal regulation and the Clean Air Act. The proposed rules do not differ from or exceed the federal requirements.

Memorandum of Notice for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment Maintenance Area August 30, 2011 Page 4INITIAL ECONOMIC IMPACT ANALYSIS Per C.R.S. 25-7-110.5 Revision to the "Air Quality Standards" Regulation
September 15, 2011

The Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area revises the PM10 emission budget in the Air Quality Standards regulation. The rule change should not result in an increase in costs to industry, the public or the Air Pollution Control Division. The updated emission budget does not impose direct costs on any party, but may affect the manner in which transportation funds are allocated and expended. The emission budget applies to transportation agencies such as the city of Steamboat Springs and the Colorado Department of Transportation, but does not impose any direct costs on these agencies. Rather than increasing costs, the emission budget may change the mix of projects eligible for transportation dollars.

Initial Economic Impact Analysis for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area August 30, 2011 Page 1FINAL ECONOMIC IMPACT ANALYSIS Per C.R.S. 25-7-110.5 Revision to the "Air Quality Standards" Regulation
December 15, 2011

The Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area revises the PM10 emission budget in the Air Quality Standards regulation. The rule change should not result in an increase in costs to industry, the public or the Air Pollution Control Division. The updated emission budget does not impose direct costs on any party, but may affect the manner in which transportation funds are allocated and expended. The emission budget applies to transportation agencies such as the city of Steamboat Springs and the Colorado Department of Transportation, but does not impose any direct costs on these agencies. Rather than increasing costs, the emission budget may change the mix of projects eligible for transportation dollars.

Final Economic Impact Analysis for Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 1

# Parties Hearing Documents

# EPA Comments 40 CFR Part 51 Appendix V 2. 1 (h)

— None Submitted

# Public Comments 

# 40 CFR Part 51 Appendix V 2.1(h)

— Letter from Routt County

— Letter from City of Steamboat Springs

### Sincerely, 

# ROUTE COUNTY BOARD OF COUNTY COMMISSIONERS Box 773598 • Steamboat Springs, Colorado 80477 • 970-879-0108 Fax: 970-879-3992

November 15, 2011

Nancy J. Stahoviak District 1 Doug Monger District 2

Diane MItsch Bush District 3

Tom Sullivan County Manager 

### Barbara Roberts Commission Chair Colorado Air Quality Control Commission 4300 Cherry Creek Drive 

### South Denver, CO 80246

RE: Revised PM 10 Maintenance 

### Plan for the Steamboat Springs Attainment/Maintenance Area
Dear Ms. Roberts, Thank you for the opportunity to review the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. The Routt County Commissioners have reviewed the document and unanimously concur with and endorse the findings of the "Plan". The Commissioners are pleased that the plan demonstrates compliance with the National Ambient Air Quality Standard (NAAQS) for PM10 through 2024. Routt County appreciates the valuable assistance that the Colorado Air Pollution Commission and Air Pollution Control Division have provided in this regard.

Diane Mits' Bush, Chair Routt County Board of County Commissioners


## RECEIVED

NOV 2 3 2011
AIR QUALITY CONTROL COMMISSION

# St clt dir'n f

boat Springs=k--*

December 15, 2011

Barbara Roberts Commission Chair Colorado Air Quality Control Commission 4300 Cherry Creek Drive South Denver, CO 80246 RE: Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area
Dear Ms. Roberts, Thank you for the opportunity to review the revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. The City of Steamboat Springs has reviewed the document and endorses the findings of the "Plan". The City of Steamboat Springs appreciates the valuable assistance that the Colorado Air Pollution Commission and Air Pollution Control Division have provided in this regard. Sincerely,

Philo S. Shelton III, 

### P.E. Public Works Director

137 10th Street, P.O. Box 775088, Steamboat Springs, Colorado 80477-5088 (970) 879-2060 • Fax (970) 879-8851 • www.steamboatsprings.net
Printed on 30% Post Consumer Fiber 

### ® OSA

# Adopted Statement of Basis, Specific Statutory Authority and PurposeVIII.BB. Steamboat Springs Adopted: December 15, 2011
Basis and Purpose The purpose of this amendment is to update the PM10 emission budget for the Steamboat Springs area in connection with the adoption of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area.
Specific Statutory Authority The Commission promulgates this regulatory change pursuant to its authority under Section 25-7- 105(1)(a)(1), C.R.S. to adopt a comprehensive state implementation plan that meets the requirements of the federal Clean Air Act.
Findings Pursuant to Section 25-7-110.8 The mobile source emission budgets are based on EPA-approved methods for calculating PM10 emissions as required by federal regulations. All methodologies and information made available by interested parties have been considered. The emission budgets reduce the potential for air pollution bycapping emissions from mobile sources. In adopting this rule, the Commission chose the most costeffective alternative.

# Adopted Language by the Commission (in redline & footer noting adoption date and page numbers)PM10: 2015 through 2021: 54 tons/day; 2022 and beyond: 55 tons/day. Nitrogen Oxides: 2015 through 2021: 70 tons/day; 2022 and beyond: 56 tons/day Trading provisions: Trading of PM10 for NOx, or NOx for PM10 to adjust emission budgets for purposes of demonstrating transportation conformity shall be allowed using the emission trading formula as follows: For trades necessary to increase a primary PM10 budget, 15.0 tons/day of NOx will be taken from the NOx budget to increase the primary PM10 budget by 1.0 tons/day, a ration of 15 to 1. For trades necessary to increase a NOx budget, 1.0 tons/day of primary PM10 will be taken from the primary PM10 budget to increase the NOx budget by 12.0 tons/day, a ratio of 1 to 12. Implementation of trading provisions: In the event the MPO cannot demonstrate consistency with the specific PM10 and NOx mobile source emission budgets, the trading provisions may be utilized only after the MPO has considered all reasonably available local control measures to meet the budgets. The MPO must demonstrate the need for trading through the usual consultation procedures for state implementation plan development delineated in Section IV (F) of AQCC Regulation Number 10, Criteria for Analysis of Conformity. If trading is utilized, the MPO shall include the following information in the transportation conformity determination: ( 1 ) The budget for primary PM10 and NOx for each required year of the conformity Denver Attainment/Maintenance Area (Modeling Domain) 

### DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT Air Quality Control Commission AIR QUALITY STANDARDS, DESIGNATIONS AND EMISSION BUDGETS
5 CCR 1001-14

V.A. Budgets V.A.1 The following Motor Vehicle Emission Budgets shall be utilized to assess the conformity of Transportation Plans, TIPs, and where appropriate, Projects, for the applicable periods and geographic areas indicated:

Air Quality Standards, Designations and Emission Budgets Regulation Adopted: December 15, 2011 Page 1determination, before trading is employed; (2) The portion of the original budget to be used to supplement a wanting budget, for each required year for the conformity determination; (3) The increased budget that results from trading, along with relevant calculations, and (4) the resulting primary PM10 and NOx budgets for each required year of the conformity demonstration. The MPO shall then compare projected emissions to the adjusted PM10 and NOx motor vehicle emission budgets to demonstrate conformity.

Denver Attainment Ozone Precursors (attainment/maintenance Maintenance Area area boundary) NOx 2002 and beyond 134 tpsd VOC 2002 and beyond 119 tpsd (tpsd = tons per summer day) Carbon Monoxide (attainment/maintenance area boundary) 2013 through 2020: 1625 tons/day; 2021 and beyond: 1600 tons/day.

Denver Metro Regional Emissions Budgets Area/North Front Range NOx: 122.9 tons/day 8-Hour Ozone VOCs: 109.2 tons/day Nonattainment Area Southern Sub-Regional Emissions Budgets NOx: 102.4 tons/day VOCs: 89.7 tons/day Northern Sub-Regional Emissions Budgets NOx: 20.5 tons/day VOCs: 19.5 tons/day

Aspen PM10 2023 and Beyond: 1,146 lbs./day Attainment/Maintenance Area Carlon City PM102020 and Beyond: 1,613 lbs./day Lamar (Modeling Area) PM102015 and Beyond: 7,534 lbs./day Pagosa Springs PM10 2021 and Beyond: 946 lbs./day (Modeling Area) Steamboat Springs

(Modeling Area) PM102015 and-Beyandthrough 2023: 21,773 lbs./day PM10 2024 and Beyond: 1,103.2 lbs./day Telluride (Modeling PM10 2021 and Beyond: 1,008 lbs./day

Air Quality Standards, Designations and Emission Budgets Regulation Adopted: December 15, 2011 Page 2Area)
Longmont Attainment/Maintenance Area Carbon Monoxide 2010 through 2014: 43 tons/day 2015-2019: 43 tons/day 2020 and Beyond: 43 tons/day Colorado Springs Attainment/Maintenance Area Carbon Monoxide 2010 and Beyond: 531 tons/day

Ft. Collins Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 99 tons/day2010 through 2014: 98 tons/day2015 and Beyond: 94 tons/day Greeley Area Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 63 tons/day2010 through 2014: 62 tons/day2015 and Beyond: 60 tons/day

VIII. Statements of Basis, Specific Statutory Authority and Purpose VIII.BB. Steamboat Springs Adopted: December 15, 2011 Basis and Purpose The purpose of this amendment is to update the PM10 emission budget for the Steamboat Springs area in connection with the adoption of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Specific Statutory Authority The Commission promulgates this regulatory change pursuant to its authority under Section 25-7- 105(1)(a)(I), C.R.S. to adopt a comprehensive state implementation plan that meets the requirements of the federal Clean Air Act. Findings Pursuant to Section 25-7-110.8 The mobile source emission budgets are based on EPA-approved methods for calculating PM10 emissions as required by federal regulations. All methodologies and information made available by interested parties have been considered. The emission budgets reduce the potential for air pollution bycapping emissions from mobile sources. In adopting this rule, the Commission chose the most costeffective alternative.

Air Quality Standards, Designations and Emission Budgets Regulation Adopted: December 15, 2011 Page 3

# State Implementation Plan Elements Adopted by the Commission (in redline & footer noting adoption date and page numbers)

# Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

Colorado Department of Public Health and Environment

10-year Revision: December 15, 2011
Original Redesignation Request and Maintenance Plan adopted by:

• The U.S. Environmental Protection Agency, October 25, 2004 (effective November 24, 2004)

• Colorado Air Quality Control Commission, November 15, 2001

Revision Prepared By: Air Pollution Control Division Colorado Department of Public Health and Environment 4300 Cherry Creek Drive South Denver, Colorado 80246

Adopted by the Air Quality Control Commission December 15, 2011

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 1

### [Blank Page]

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 2

### TABLE OF CONTENTS

TABLE OF CONTENTS 3

SECTION 1: INTRODUCTION 4
A. BACKGROUND 5 1. PM10 National Ambient Air Quality Standard (NAAQS) 5 2. Health and Welfare Effects of PM10 5 3. Steamboat Springs Nonattainment Area Classification History 6 4. Steamboat Springs Attainment/Maintenance Area Boundary 6 Figure 1: Map of the Steamboat Springs Attainment/Maintenance Area 7 B. ORGANIZATIONS INVOLVED IN PREPARING/APPROVING PLAN 8
SECTION 2: PM10 ATTAINMENT HISTORY 9

A. MONITORING HISTORY 9 Table 1: Steamboat Springs PM10 Monitoring Record 9 B. DESIGN VALUE DETERMINATION 9
SECTION 3: STATE IMPLEMENTATION PLAN APPROVAL 11
A. 1995 SIP ELEMENT 11 B. 1996 SIP ELEMENT 11 C. PM10 MAINTENANCE PLAN 11 SECTION 4: PERMANENT AND ENFORCEABLE IMPROVEMENT IN AIR QUALITY 12
A. OVERVIEW 12 B. CONTROL MEASURES 12 1. Woodburning Emission Controls 13 2. Street Sanding Controls 13 3. Street Sweeping Requirements 13 4. Control of Emissions from Stationary Sources 13 5. Federal Motor Vehicle Emission Control Program 14
SECTION 5: MAINTENANCE PLAN 15
A. REQUIREMENTS 15 B. EMISSION INVENTORIES 16 1. 2008 Base Year Emission Inventory 16 Table 2: 2008 PM10 Base Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 17 2. 2016 Interim Year Emission Inventory 17 Table 3: 2016 PM10 Interim Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 17 3. 2024 Maintenance Year Emission Inventory 18 Table 4: 2024 PM10 Maintenance Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 18 C. MAINTENANCE DEMONSTRATION 19 D. PM10 EMISSION BUDGET 20 E. MONITORING NETWORK/VERIFICATION OF CONTINUED ATTAINMENT 20 F. CONTINGENCY PLAN 20 1. Tracking 20 2. Trigger and Response 21 3. Potential Contingency Measures 22 G. SUBSEQUENT MAINTENANCE PLAN REVISIONS 22

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 3

## SECTION 1: INTRODUCTION This document is the second PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. The U.S. Environmental Protection Agency (EPA) first approved a PM10 redesignation request and maintenance plan for the Steamboat Springs area on October 25, 2004 (69 FR 62210), which became effective on November 24, 2004. The redesignation request and maintenance plan was adopted by the Colorado Air Quality Control Commission on November 15, 2001. This second maintenance plan was prepared to meet the provisions of section 175A(b) of the Clean Air Act and contains the same emission control strategies as the first maintenance plan that was adopted by the commission in 2001. The 2011 plan includes updated emission inventories and projections using the latest EPA-approved tools. This plan establishes a new PM10 motor vehicle emission budget (MVEB) of 1,103 pounds per day in 2024. The City of Steamboat Springs, Routt County, and the state of Colorado request continuation of "attainment/maintenance" status for the Steamboat Springs PM10 Attainment/Maintenance Area. The Steamboat Springs area originally was designated as nonattainment for the National Ambient Air Quality Standard (NAAQS) for particulate matter with an aerodynamic diameter of ten microns or less (PM10) in 1993 (effective January 20, 1994). The area presently is demonstrating attainment with the PM10 NAAQS. The Maintenance Plan section of this document has been updated and will demonstrate that the area will be able to maintain compliance with the NAAQS through the year 2024. The benefits of maintaining attainment/maintenance status include: 1. Areas that maintain attainment/maintenance status no longer carry the stigma associated with nonattainment of the NAAQS. 2. Attainment areas will not become "serious" nonattainment areas even if a violation of the NAAQS occurs in the future. This means that specific control measures can be applied to address a violation without going through a rigorous federal process, where serious areas must implement mandatory control measures and be subject to numerous administrative activities. 3. Prevention of Significant Deterioration (PSD) permitting requirements continue to replace New Source Review (NSR) permitting requirements for new and modified major stationary sources. These permitting requirements are important for large industrial facilities that currently are not located, nor likely to locate, in the Steamboat Springs area. This plan is designed to document and ensure continuing attainment and maintenance of the NAAQS for PM10 in the Steamboat Springs area. This document is intended to comply with requirements of the federal Clean Air Act (CAA), and with relevant procedures and policies of the U.S. Environmental Protection Agency (EPA).

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 4

### A. BACKGROUND

1. PM10 National Ambient Air Quality Standard (NAAQS) In 1971, the EPA set NAAQS for several air pollutants, including total suspended particulates (TSP), defined as particles with an aerodynamic diameter of less than 40 microns. In 1987, the EPA changed the TSP standards by setting NAAQS for PM10, defined as particles with an aerodynamic diameter of ten microns or less (PM10). The current PM10 NAAQS allow for a maximum 24-hour average concentration of 150 ug/m3. The 24-hour PM10 NAAQS may not be exceeded more than once per year on average over any three-year period. There are both primary and secondary air quality standards. The primary standards are set to protect human health with a margin of safety to protect the more sensitive persons in the population like the very young, elderly and the ill. Secondary standards are set to protect property, materials, aesthetic values and general welfare. For PM10, the national primary and secondary standards are the same. The numerical levels of the standards are subject to change, based on new scientific evidence summarized in air quality criteria documents. In 2006, the EPA revoked the annual PM10 standard but retained the 24-hour average of 150 ug/m3 (71 FR 61144) for both the primary and secondary NAAQS. In general, demonstrating attainment requires collecting representative air monitoring data and using approved measuring instruments and procedures, with adequate quality assurance and quality control. Air quality measurements in the Steamboat Springs area satisfy this requirement, as shown in Section 2 (Table 1 — Steamboat Springs PM10 Monitoring Record).



### 2. Health and Welfare Effects of PM10 Particulate matter is the term given to tiny particles of solid or semi-solid material suspended in the atmosphere. PM10 refers to a subset of particulate matter 10 micrometers in diameter and smaller. PM10 is inhalable. In the Steamboat Springs area, PM10 is created primarily from re-entrained road dust, carbon black (from automobile and diesel engines) and soot (from fireplaces and woodstoves). PM10 from these combustion sources contains a large percentage of elemental and organic carbon, which contributes to atmospheric haze and to health problems. Additional PM10 sources, to a lesser degree, include restaurant grills and aircraft. Epidemiological studies and laboratory studies of humans and animals indicate that particulate matter can be inhaled deeply into the respiratory system, resulting in aggravation of existing respiratory and heart diseases, damage to lung tissue, impairment of breathing and respiratory functions, alterations to the body's physical and immune system defenses, and even premature death. Many particles also are composed of compounds that are known or suspected human carcinogens. People

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 5

### most sensitive to particulate matter are the elderly, children, and those with chronic lung disease, cardiovascular disease, influenza, and asthma.

The welfare effects of particulate air pollution are widespread. Chemical and photochemical reactions involving the particles may occur in the air, or once they have been deposited on environmental media or structures. Such soiling and acid deposition cause visibility degradation, climate changes, and damage to crops, natural vegetation, water bodies, and aquatic life. In addition, sculpture and architecture may be damaged or destroyed by particulate soiling and acid deposition. 

## 3. Steamboat Springs Nonattainment Area Classification History Because of observed problems with air particles, monitoring for PM10 began in 1985. Based upon numerous exceedances of the 24-hour PM10 NAAQS, the Steamboat Springs area was designated by the EPA as a "moderate" nonattainment area in 1993 pursuant to section 107(d)(3)(B) of the Clean Air Act.


## 4. Steamboat Springs Attainment/Maintenance Area Boundary The boundary for the Steamboat Springs PM10 Attainment/Maintenance Area is defined as follows: On the East: 

### The Routt National Forest

On the South: 

### The southern border of sections 19, 20, 21, T4N, R84W of the 6th P.M. and the southern border of sections 23, 24, 

## T4N, R85W of the 6 th P.M. Beginning at the southwestern corner of section 23, 

## T4N, R85W of the 6 th P.M., north along the western border of sections 23, 14, 11, T4N, R85W. Thence, along the ridge which bisects sections 35, 36, 25, 24, 13, 14, 11, 12, 1, T5N, R85W, and sections 36, 25, 24, T6N, R85W. Thence, heading northwest along the ridge which bisects sections 23, 15, 10, 9, 4, T6N, R85W of 6 th P.M. Thence heading northeast along the ridge which bisects sections 33, 34, 35, 36, 25 T7N, R85W and sections 30 and 19 of T7N, R84W. Thence, north along the N 1 /2 of the western edge of section 19, to the NW corner of section 18, T7N, R84W. On the West:

On the North: 

### The northern boundary of sections 16, 17, 18 T7N, R84W of the 6 th P.M. A map illustrating the area boundary is shown in Figure 1.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 6

### Steamboat Springs PM-10 Attainment Area

Legend

4 + Steamboat Springs Airport



# • Point Sources CITY



# *
PM10 Monitor RAIL_LIN ES Major Roads HIGHWAYS LocalRoads City of Steamboat Springs NAM E Steamboat Springs Attainment Area

0 1 25 25 5 Miles 

### Figure 1: Map of the Steamboat Springs Attainment/Maintenance Area

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 7

### B. ORGANIZATIONS INVOLVED IN PREPARING/APPROVING PLAN Preparation of this revised maintenance plan was a cooperative effort of the City of Steamboat Springs, Routt County, and the Air Pollution Control Division (APCD) of the Colorado Department of Public Health and Environment. The EPA, through its regional office in Denver, provided policy advice and technical assistance, and is responsible for final approval of this revised maintenance plan.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 8

## SECTION 2: PM10 ATTAINMENT HISTORY

A. MONITORING HISTORY Monitoring for PM10 in Steamboat Springs began in 1985. Numerous exceedances of the 24-hour PM10 NAAQS were the basis for the Steamboat Springs area being designated as a "moderate" nonattainment area in 1993 (effective January 20, 1994). Table 1 lists the yearly maximum, yearly estimated exceedances and the 3-year average estimated exceedances for the Steamboat Springs monitoring site(s) for the 10-year period from 2001 through 2010. The state of Colorado maintains a PM10 monitor at 136 6 th 

### Street in Steamboat Springs.



### Table 1: Steamboat Springs PM10 Monitoring Record

Year Maximum Concentration (ug/m 3 ) Yearly Estimated Exceedances 3-yr Average Estimated Exceedances 2001 100 0 0 2002 119 0 0 2003 149 0 0 2004 94 0 0 2005 86 0 0 2006 87 0 0 2007 99 0 0 2008 124 0 0 2009 83 0 0 2010 99 0 0


### B. DESIGN VALUE DETERMINATION The "design value" is the critical air quality value upon which the maintenance plan is based. The design value, and the conditions that occurred on the day which it was measured, are utilized to develop emission inventories and serve as a baseline for modeling ambient concentrations into the future. The selection of the design value used in this revised maintenance plan utilized the EPA's table look-up method from the EPA's "PM10 SIP Development Guideline" document.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 9

### Based on the number of samples collected during the 2008 - 2010 period (999), the third highest concentration is the design value, according to this guidance. The three highest concentrations measured during the period 2008 -2010 are as follows:

** 124 ug/m3 — February 18, 2008 ** 111 ug/m3 — February 20, 2008 ** 99 ug/m3 — February 3, 2010 Consequently, the design value used for this revised maintenance plan is 99 ug/m3.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 10

## SECTION 3: STATE IMPLEMENTATION PLAN APPROVAL The following presents a brief summary of the development and the approval of the Steamboat Springs PM10 Nonattainment State Implementation Plan (SIP) Element.



### A. 1995 SIP ELEMENT The first Steamboat Springs SIP Element was adopted by the Colorado Air Quality Control Commission (AQCC) in September 1995. The control measures included: 1) local restrictions on woodburning devices, 2) specifications for street sanding materials (no more than 1% fines allowed), and 3) street sweeping requirements on Lincoln Avenue (once after each sanding event). The plan also included monitoring data, emission inventories, and dispersion modeling which demonstrated attainment of the PM10 NAAQS by December 1999 and continuing through December 2002. The EPA did not approve this SIP Element at the request of the state due to revisions to control measures and modeling that occurred before EPA could take action on the plan.



### B. 1996 SIP ELEMENT A new Steamboat Springs PM10 SIP Element was adopted by the AQCC in October 1996. The control measures were revised to include: 1) local restrictions on woodburning devices, 2) specifications for street sanding materials (no more than 2% fines allowed), 3) street sweeping requirements on Lincoln Avenue (four times after each sanding event), and 4) street sand reductions of 10% on state highways. The plan also included revised monitoring data, emission inventories, and dispersion modeling which demonstrated attainment of the PM10 NAAQS by December 1999 and continuing through December 2002. In addition, contingency measures (additional street sweeping if the area violated the NAAQS and an emergency episode plan (suspension of open burning, voluntary wood and coal burning curtailment, and voluntary driving reductions if a NAAQS exceedance was expected) were adopted. This SIP Element was approved by the EPA on December 31, 1997 (62 

### FR 68188).



### C. PM10 MAINTENANCE PLAN The Colorado Air Quality Control Commission approved the Steamboat Springs PM10 Maintenance Plan on November 15, 2001. The EPA subsequently approved the plan on October 25, 2004, which became effective on November 24, 2004.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 11

## SECTION 4: PERMANENT AND ENFORCEABLE IMPROVEMENT IN AIR QUALITY

The state of Colorado must demonstrate, based on Section 107(d)(3)(E) of the Clean Air Act, that the improvement in air quality leading to attainment and continued compliance with the NAAQS is based on permanent and enforceable measures, and that the reductions are not the result of temporary reductions in emissions or unusually favorable meteorology.



### A. OVERVIEW It is reasonable to attribute the continued attainment of the PM10 NAAQS in the Steamboat Springs Attainment/Maintenance Area to emission reductions that are permanent and enforceable. These emission reductions are the result of local, state, and federal actions, not economic factors or unusual meteorology. Economic conditions are not responsible for improved ambient levels in the Steamboat Springs Attainment/Maintenance Area. It is assumed that growth in population and tax revenue are indicators of increased activities that cause increased 

### PM10 emissions and the potential for elevated PM10 concentrations. Information obtained for the City of Steamboat Springs shows that, during the period 2000 through 2007, general sales and use revenues increased by 71.21 percent, while Routt County population increased by 16.85 percent over the same period. During this period, attainment of the PM10 NAAQS was demonstrated with no exceedances recorded. Favorable meteorology also is an unlikely reason. Although winter and spring meteorological conditions are highly variable in mountain settings, there is no evidence to suggest that meteorological conditions experienced in the 2000s have not been "typical" (though it is difficult to make concrete conclusions based on short-term meteorological records). Because there has not been a violation of the PM10 NAAQS in Steamboat Springs since 1996, the Air Pollution Control Division concludes that the good air quality in the Steamboat Springs area is the result of the implementation of emission reduction measures, not meteorological fluctuations.



### B. CONTROL MEASURES The following control measures resulted in the area's attainment of the PM10 NAAQS, and these measures should ensure continued maintenance of the PM10 NAAQS through the year 2024, which is the duration of the maintenance period.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 12

## 1. Woodburning Emission Controls The City of Steamboat Springs and Routt County have adopted local ordinances and resolutions that limit the number and types of woodburning devices in new construction in the Steamboat Springs area. Installation of new solid fuel burning devices is limited to one approved device for any building. These requirements were adopted locally in the late 1980s and early 1990s and included in state regulation in 1995 {Section VIII.E.of the "State Implementation Plan-Specific Regulations for NonattainmentAttainment/Maintenance Areas (Local Elements)}. The rule was approved by the U.S. EPA in 1997. The requirements will remain part of state regulation and the federal State Implementation Plan (SIP). 

## 2. Street Sanding Controls There is a requirement that any user that applies street sanding materials in the Steamboat Springs Attainment/Maintenance Area must use materials containing less than two percent fines, except on U.S. Highway 40 from the junction of U.S. Highway 131 toward Rabbit Ears Pass. This requirement was adopted in 1996 and approved by the U.S. EPA in 1997, and is defined in detail in Section VIII.B. of the {State Implementation Plan-Specific Regulations for Nonattainment-Attainment/Maintenance Areas (Local Elements)}. The requirement will remain part of state regulation and the federal SIP. 

## 3. Street Sweeping Requirements There are street sweeping requirements for a defined section of Lincoln Avenue (Highway 40 in Steamboat Springs). Beginning with the effective date of the U.S. EPA's approval of the initial maintenance plan (November 24, 2004), street cleaning using vacuum sweepers or any other sweepers with equal efficiency must occur two times within the four-day period of the roadways becoming free and clear of snow and ice following each sanding deployment use. These requirements are defined in detail in Section VIII.D. of the {State Implementation Plan-Specific Regulations for Nonattainment-Attainment/Maintenance Areas (Local Elements)}. The requirements will remain part of state regulation and the federal SIP. 

## 4. Control of Emissions from Stationary Sources The state's comprehensive permit rules limit emissions from any new source that may, in the future, locate in the Steamboat Springs area. These rules include: 1) CAQCC Regulation No. 3, "Air Pollution Emission Notices, Construction Permits and Fees, Operating Permits, and Including the Prevention of Significant Deterioration," 2) the "Common Provisions" regulation, and 3) CAQCC Regulation No. 6, "standards for Performance for New Stationary Sources." The Common Provisions, and Parts A and B of CAQCC Regulation No. 3, already are included in the SIP. CAQCC Regulation No. 6 implements the federal standards of performance for new stationary sources. As was the case with the initial maintenance

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 13plan, this revised maintenance plan makes no changes to these regulations. This reference to CAQCC Regulation No. 6 shall not be construed to mean that this regulation is included in the SIP. Emissions of PM10 from new or modified major stationary sources are controlled under CAQCC Regulation No. 3's nonattainment area New Source Review (NSR) permitting requirements. The NSR provisions require all new and modified major stationary sources to apply emission control equipment that achieves the "lowest achievable emission rate" (LAER) and to obtain emission offsets from other stationary sources of PM10. The PSD requirements are a relaxation from the NSR requirements, as LAER becomes the less stringent "Best Available Control Technology" (BACT), and offsets are not required. The application of these provisions is possible, but not foreseen, in the Steamboat Springs area. It should be noted that significant additional controls at both the Tri-State Generation and Transmission Association's Craig Generating Station and the Xcel Energy Hayden Generating Station that are part of the Colorado Visibility and Regional Haze State Implementation Plan will be installed during the effective period of this revised plan.


### 5. Federal Motor Vehicle Emission Control Program The Federal Motor Vehicle Emission Control Program has reduced PM10 emissions through a continuing process of requiring diesel engine manufacturers to produce new vehicles that meet tighter and tighter emission standards. As older, higher-emitting diesel vehicles are replaced with newer vehicles, PM10 emissions in the Steamboat Springs area will be reduced.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 14

## SECTION 5: MAINTENANCE PLAN
A. REQUIREMENTS Section 107(d)(3)(E) of the Clean Air Act (CAA) provides that, for an area to be redesignated to an attainment classification, the U.S. EPA must fully approve a maintenance plan which meets the requirements of CAA Section 175A. The maintenance plan will constitute a SIP revision and must provide for maintenance of the relevant NAAQS in the area for at least ten years after redesignation. The EPA first approved a PM10 redesignation request and maintenance plan for the Steamboat Springs area on October 25, 2004 (69 FR 62210), which became effective on November 24, 2004. An additional requirement (Section 175A(b)) is the submittal of a SIP revision eight years after the original redesignation request/maintenance plan is approved that provides for maintenance of the NAAQS for an additional ten years following the first ten-year period. The state of Colorado has satisfied this commitment by submitting this revised maintenance plan as required by the CAA and EPA requirements. Section 175A further states that the plan shall contain such additional control measures as necessary to ensure maintenance. All current nonattainment area control measures shall remain in place, except for the most stringent NSR stationary source permitting requirements (see Section 4.B.4.). This maintenance plan revision shall contain a contingency plan to ensure the prompt correction of any unforeseen violation of the PM10 NAAQS. Failure to maintain the NAAQS and triggering of the contingency plan will not necessitate a revision of the SIP Element, unless required by the EPA Administrator, as stated in CAA Section 175A(d). The provisions that are addressed in this maintenance plan revision include emission inventories (for a base year, an interim year and a maintenance year), a maintenance demonstration, an emission budget, an approved monitoring network, verification of continued attainment, and a contingency plan.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 15

### B. EMISSION INVENTORIES The emission inventories below include the 2008 base year, the 2016 interim year and the 2024 maintenance year. These inventories reflect the base and projected conditions in the Steamboat Springs Attainment/Maintenance Area, and account for the emission control measures that were adopted as part of the original redesignation request and the previous 10-year maintenance plan. Unlike the previous Steamboat Springs plan where the emission inventories were based on a grid system of the attainment/maintenance area, the updated emission inventories for 2008, 2016 and 2024 are based on a number of EPA-approved emission modeling methods that are detailed in the Technical Support Document. Consequently, there are significant differences between the emission inventories in the previous plan and this revised and updated PM10 maintenance plan.



### 1. 2008 Base Year Emission Inventory The 2008 Base Year Emission Inventory for the Steamboat Springs Attainment/Maintenance Area is presented below. This updated emission inventory incorporates the most current estimates for the following 10 source categories:

• Commercial Cooking

• Construction

• Fuel Combustion

• Highway Vehicles

• Non-Road

• Paved/Unpaved Road Dust

• Point Sources

• Railroad

• Structure Fires

• Woodburning
The mobile source inventory (paved/unpaved road dust and highway vehicles) has been updated to reflect the following:

• Latest traffic (VMT) estimates from the Colorado Department of Transportation

• Revised emission factors and methods for determining paved road emissions

• Road paving of unpaved roads that has occurred in the area

• Vehicle exhaust emissions based on most up-to-date fleet mix

All emission estimates were prepared by using EPA-approved methods and assigned to the area comprising the Steamboat Springs Attainment/Maintenance Area.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 16

### Table 2 presents the 2008 PM10 Base Year emission estimates for each source category in tons per year and pounds per average day.

Table 2: 2008 PM10 Base Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2008 PM10 [tons/year] 2008 PM10 [lbs/day] Commercial Cooking 2.92 16.6 Construction 640.58 3509.7 Fuel Combustion 1.46 8.6 Highway Vehicles 25.55 140.5 Non-Road 16.43 89.6 Point Sources 33.95 185.1 Railroad 0.73 3.6 Road Dust 121.18 663.4 Structure Fires 0.00 0.7 Woodburning 87.24 478.0 Totals: 930.02 5095.9

2. 2016 Interim Year Emission Inventory 

### Table 3 presents the 2016 PM10 Interim Year emission estimates for each source category in tons per year and pounds per average day.

Table 3: 2016 PM10 Interim Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2016 PM10 [tons/year] 2016 PM10 [lbs/day] Commercial Cooking 3.65 20.5 Construction 789.68 4326.4 Fuel Combustion 1.83 10.6 Highway Vehicles 31.94 175.1 Non-Road 12.60 68.6 Point Sources 41.80 228.2 Railroad 0.92 4.5 Road Dust 142.17 778.5 Structure Fires 0.19 0.85 Woodburning 107.50 589.3 Totals: 1131.87 6202.4

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 17

### 3. 2024 Maintenance Year Emission Inventory Table 4 presents the 2024 PM10 Maintenance Year emission estimates for each source category in tons per year and pounds per average day.

Table 4: 2024 PM10 Maintenance Year Emission Inventory (Steamboat Springs Attainment/Maintenance Area) 

### Source Category 2024 PM10 [tons/year] 2024 PM10 [lbs/day] Commercial Cooking 4.38 24.4 Construction 938.78 5143.1 Fuel Combustion 2.19 12.6 

### Highway Vehicles 38.33 209.6 Non-Road 8.76 47.5 Point Sources 49.64 271.3 Railroad 1.10 5.3 Road Dust 163.16 893.6 Structure Fires 0.37 1.0 Woodburning 127.75 700.5 

### Totals: 1333.71 7308.8

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 18

### C. MAINTENANCE DEMONSTRATION This maintenance plan revision provides for continued maintenance of the 24-hour PM10 NAAQS through the year 2024, the 20-year period after the original redesignation request and maintenance plan was approved by the U.S. EPA in 2004. Because there have never been any exceedances of the annual PM10 NAAQS in Steamboat Springs, an analysis for maintenance of the annual standard was not prepared for the original redesignation request and maintenance plan. The EPA subsequently revoked the annual standard in 2006. A design day concentration of 99 ug/m3 has been selected as a conservative value that represents the third-highest 24-hour maximum PM10 value recorded in Steamboat Springs during 2008-2010. This 99 ug/m3 concentration occurred on February 3, 2010. No reduction for background values has been taken into account for the design day value, making the 99 ug/m3 a conservative estimate of PM10 ambient air concentrations in Steamboat Springs. The design value likely overstates the actual amount of PM10. The emission inventory data presented in this document is used to determine the growth in PM10 emissions from the 2008 base year to the 2024 maintenance year. The emission inventory shows an increase in PM10 from 5,095.9 pounds per day in 2008 to 7,308.8 pounds per day in 2024. This represents an increase of 43.4 percent in emissions: 7308.8/5095.9 = 1.434, or 43.4 percent. The design day concentration of 99 ug/m3 of PM10 is then increased 43.4 percent to "roll forward" to the 2024 attainment year. This roll-forward modeling results in a 2024 concentration of approximately 142 ug/m3: 99 ug/m3 x 1.434 = 142 ug/m3 Since 142 ug/m3 is below the 150 ug/m3 standard, maintenance is demonstrated through 2024.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 19

### D. PM10 EMISSION BUDGET Federal "transportation conformity" regulations provide for the use of mobile source emission budgets in making conformity determinations in the area. The emission budget serves as a ceiling on mobile source emissions that federally funded or approved transportation projects must comply or conform. This maintenance plan revision establishes a new PM10 motor vehicle emission budget (MVEB) for the Steamboat Springs Attainment/Maintenance Area of 1,103 lbs/day for 2024. This budget is the total of the 2024 mobile source PM10 emissions (see Section 5.B.3. above), which includes PM10 emissions from highways and paved/unpaved road dust. This budget has been adopted in the AQCC's "Air Quality Standards - Air Quality Standards, Designations and Emissions Budgets" regulation.



### E. MONITORING NETWORK/VERIFICATION OF CONTINUED ATTAINMENT The Air Pollution Control Division has monitored ambient PM10 concentrations in the Steamboat Springs area since 1985. The division has operated, and will continue to operate, the Steamboat Springs PM10 monitoring network in full accordance with the federal provisions of 40 CFR Part 58 and the EPA-approved Colorado Monitoring SIP Element. The division also will analyze the monitoring data to verify continued attainment of the PM10 NAAQS. This information will provide the necessary information to determine whether the Steamboat Springs area continues to attain the PM10 NAAQS. Detailed information regarding the state's monitoring efforts and historical monitoring data can be found in Section 2 of this document.



### F. CONTINGENCY PLAN Section 175(A)(d) of the Clean Air Act requires that the maintenance plan contain contingency provisions to assure that the state will promptly correct any violation of the PM10 NAAQS that may occur after the redesignation of the area to attainment. The EPA's redesignation guidance notes that the state is not required to have fully adopted contingency measures that will take effect without further action by the state. However, the contingency plan should ensure that contingency measures are adopted expediently once the need is triggered. The primary elements of the contingency plan involve the tracking and triggering mechanisms to determine when contingency measures would be needed, and a process for implementing appropriate control measures.



### 1. Tracking The tracking plan for the Steamboat Springs area will consist of monitoring and analyzing PM10 concentrations. In accordance with 40 CFR Part 58, Colorado will continue to operate and maintain the Steamboat Springs PM10 monitoring network.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 20

### 2. Trigger and Response Triggering of the contingency plan does not automatically require a revision of the SIP nor is the area necessarily redesignated once again to nonattainment. Instead, the state normally will have an appropriate timeframe to correct the violation with implementation of one or more adopted contingency measures. In the event that violations continue to occur, additional contingency measures will be adopted until the violations are corrected. Upon notification of a PM10 NAAQS exceedance, the Air Pollution Control Division and local government staff in the Steamboat Springs area will develop appropriate contingency measure(s) intended to prevent or correct a violation of the PM10 standard. Information about historical exceedances of the standard, the meteorological conditions related to the recent exceedance(s), and the most recent estimates of growth and emissions will be reviewed. The possibility that an exceptional event occurred also will be evaluated (notification to the EPA and to the local governments in the Steamboat Springs area of any exceedance generally will occur within 30 days, but no later than 45 days). This process will be completed within six months of the exceedance notification. If a violation of the PM10 NAAQS has occurred, a public hearing process at the state and local level will begin. If the AQCC agrees that the implementation of local measures will prevent further exceedances or violations, the AQCC may endorse or approve of the local measures without adopting state requirements. 

### If, however, the AQCC finds locally-adopted contingency measures to be inadequate, the AQCC will adopt state-enforceable measures as deemed necessary to prevent additional exceedances or violations. Contingency measures will be adopted and fully implemented within one year of a PM10 NAAQS violation. Any state-enforceable measures will become part of another revised maintenance plan, submitted to the Colorado Legislature and the EPA for approval.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 21

### 3. Potential Contingency Measures The APCD and local government staff may choose one or more of the following contingency measures to recommend to local officials and the AQCC for consideration. Contingency measures will be selected that quickly bring the area back into compliance with the PM10 NAAQS and that specifically meet the needs of the Steamboat Springs area. It is likely that no federal or state monies will be available to fund the implementation of the selected contingency measure(s). Most, if not all, of the costs will be borne by local citizens and governments, local businesses, and state government agencies.

• Increased street sweeping requirements

• Road paving requirements

• More stringent street sand specifications

• Voluntary or mandatory woodburning curtailment

• Bans on all woodburning

• Expanded, mandatory use of alternative de-icers

• Re-establishing new source review permitting requirements for stationary sources

• Transportation control measures designed to reduce vehicle miles traveled

• Other emission control measures appropriate for the area based on the consideration of cost-effectiveness, PM10 emission reduction potential, economic and social considerations, or other factors that the state deems appropriate 

### G. SUBSEQUENT MAINTENANCE PLAN REVISIONS This revised maintenance plan provides for continued maintenance of the PM10 NAAQS for an additional ten years beyond the original ten-year period. Consequently, no further maintenance plan updates are anticipated.

PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area December 1, 2011 Page 22Colorado Department of Public Health and Environment / Air Pollution Control Division



# Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area

Technical Support Document Emission Inventory

December 15, 2011 Colorado Department of Public Health and Environment 

### Air Pollution Control Division 4300 Cherry Creek Drive South Denver, Colorado 80246

Adopted by the Air Quality Control Commission December 15, 2011

Revised PM1 0 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory December 1, 2011Colorado Department of Public Health and Environment / Air Pollution Control Division



# Table of Contents

1. EMISSION INVENTORY METHODOLOGY 2. 2008 AND 2024 EMISSION INVENTORY SUMMARIES 3 3. REFERENCES 4

ii Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory December 1, 2011

### Colorado Department of Public Health and Environment / Air Pollution Control Division



## 1. Emission Inventory Methodology The Air Pollution Control Division (APCD) developed the 2008 and 2024 emission inventories in the "PM10 Maintenance Plan for Steamboat Springs" using U.S. Environmental Protection Agency (EPA) approved emissions modeling methods, including EPA's MOVES2010a model and local VMT data for on-road mobile source emissions, EPA's non-road model, local demographic information for area and off-road sources, and reported actual emissions for point sources. Estimates for future emissions are based on the above-mentioned tools and population estimates from the State Demographer. The inventory represents average daily winter emissions. The MOVES2010a and non-road model inputs represent these average daily winter conditions. Heating and wood burning emissions were apportioned from annual emission estimates by heating degree day data from the Western Regional Climate Center. Other source categories were apportioned from annual to daily by dividing by 365.

Highway mobile source emissions are from the EPA model MOVES2010a, an emission factor model for predicting gram per mile emissions of Hydrocarbons (HC), Carbon Monoxide (CO), Nitrogen Oxides (NOx), Carbon Dioxide (CO2), Particulate Matter (PM), and toxics from cars, trucks, and motorcycles under various conditions. Non-road source emissions are from the EPA Non-Road Model. This model includes the impact of future controls on non-road engines, which is used in equipment such as lawn and garden equipment and construction equipment. Area source emissions (including heating, construction, commercial cooking, etc.) are from the 2008 EPA National Emissions Inventory (NEI), grown to 2024 by population growth from data from the State. For more documentation for these categories, refer to the NEI documentation (EPA, 2010). Wood burning and road dust emissions were calculated using local data and EPA AP-42 emission factors.

The MOVES2010A and Non-Road Models and the NEI report emissions for Routt County as a whole. Emissions were apportioned to the Attainment Area using geographical information system (GIS) techniques, using population, VMT and land area. Under Air Quality Control Commission Regulation No. 3, the APCD requires any source that emits two tons per year or greater to submit an Air Pollutant Emission Notice (APEN) (APCD, 2008). This means that sources that emit less than two tons per year are not necessarily accounted for in an emissions inventory. The point source emissions for Steamboat Springs were obtained from this tracking system. The emission estimates are made using a variety of methodologies. Data from source-specific emission tests, or continuous emission monitors are preferable, but not always available. The EPA has developed a variety of emission factors to estimate emissions as well. Emission factors are frequently the best or only method available for estimating emissions.

1 Revised PMIO Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory 

### December 1, 2011

## Steamboat Springs PM-10 Attainment Area

Legend
Steamboat Springs Airport 

# • Point Sources CITY PM10 Monitor 41---1- RAIL_LIN ES Major Roads HIGHWAYS LocalRoads City of Steamboat Springs NAM E Steamboat Springs Attainment Area

0 126 25 5 Miles Colorado Department of Public Health and Environment / Air Pollution Control Division

Revised PMIO Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory December 1, 2011Colorado Department of Public Health and Environment / Air Pollution Control Division


## 2. 2008 and 2024 Emission Inventory Summaries This section presents the 2008 and 2024 emission inventories for the maintenance plan.

Table 1. PM10 Emission Inventories Based on 2008 NEI and Projected by Population (except as noted)

Steamboat Springs Attainment Area 2008 2024 Category PM10 t/d PM10 Pounds/d PM10 t/d PM10 Pounds/d Commercial Cooking 0.008 16.6 0.012 24.4 Construction 1.755 3,509.7 2.572 5,143.1 Fuel Combustion 0.004 8.6 0.006 12.6 Highway Vehicles* 0.070 140.5 0.105 209.6 Non-Road** 0.045 89.6 0.024 47.5 Railroad 0.002 3.6 0.003 5.3 Road Dust*** 0.332 663.4 0.447 893.6 Structure Fires 0.000 0.7 0.001 1.0 Woodburning  0.239 478.0 0.350 700.5 Point Sources** *** 0.093 185.1 0.136 271.3 TOTAL 2.548 5,095.9 3.654 7,308.8

* Based on MOVES, CDOT VMT ** Based on NonRoad Model *** Based on Latest AP-42, CDOT VMT   Based on AP-42, Projected by Population as of 4/25/2011 data from State Demographer ** *** Based on APENS, Projected by Population as of 4/25/2011 data from State Demographer

Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory December 1, 2011 3

### Colorado Department of Public Health and Environment / Air Pollution Control Division



## 3. References APCD, 2008. Air Quality Control Commission Regulation Number 3. Stationary Source Permitting and Air Pollutant Emission Notice Requirements. 5 CCR 1001-5. < http : //www. cdphe

.

### state .co .us/regulations/airreg s/100 103 st ationarysourcepermitting.pdf 

### > U.S. EPA, 2010. "2008 National Emissions Inventory Data & Documentation." < http://www.epa.govittn/chief/net/2008inventory.html 

### >

Revised PMIO Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area Technical Support Document - Emission Inventory December 1, 2011

# Colorado Air Quality Control Commission Meeting Minutes 

# 40 CFR Part 51 Appendix V 2.1(g)Phone (303) 692-3100 Fax (303) 691-7702 TDD (303) 691-7700 Colorado Department of Public Health and Environment 

# STATE OF COLORADO

John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH, Executive Director and Chief Medical Officer COLORADO AIR QUALITY CONTROL COMMISSION hup://www.cdphe.state.co.us 4300 Cherry Creek Drive South OED-OLRA-A5 Denver, Colorado 80246-1530 

# Colorado Air Quality Control Commission December 15, 2011 MEETING MINUTES

Location: 

### Colorado Department of Public Health & Environment 4300 Cherry Creek Drive South, Sabin Room Denver, CO 80246

Members Present: 

### Ashley Campsie Teresa Coons John Loewy Barbara Roberts Jon Slutsky Jim Wilson

Members Absent: 

### Robert Arnott Saeed Barhaghi Dawn Meyers
Commission Staff: 

### Mike Silverstein Theresa Martin
Division Staff: 

### Will Allison Lisa Silva Lisa Clarke Pat McLaughlin Gordon Pierce 

### Attorney General's Office: Andrea Gelfuso-Goetz

CALL TO ORDER AND DETERMINATION OF A QUORUM 

### Chair Roberts called the meeting to order at 9:05 AM and determined that a quorum of 

### Commissioners was now present with six Commissioners.

APPROVAL OF MEETING MINUTES FOR OCTOBER 

### 20, 2011 Chair Roberts asked the Commission if there were any modifications to the minutes. Roberts had one edit changing Traditional Agenda to Regular Agenda.

Motion: To approve the October 20, 2011 Meeting Minutes Moved: Commissioner Campsie Second: Commissioner Coons Discussion: none Carried: 6-0

### PUBLIC COMMENT Chair Roberts asked if there were any members of the public who wished to make a comment on any air pollution issue not on the agenda. There were no public comments.
CONSENT AGENDA REQUEST FOR PUBLIC HEARING



### • Pikes Peak Area Council of Governments (PPACG) Conformity Determination

RULEMAKING HEARINGS



### • Regulation Number 9: Smoke Management Distribution of Costs as prepared by the Division

• PM2.5 Interstate Transport State Implementation Plan as prepared by the Division

• Steamboat Springs PM 10 Maintenance Plan as prepared by the Division

Motion: Moved: Second: Discussion: Carried: To adopt the Consent Agenda items Commissioner Wilson Commissioner Slutsky
none 6-0
REGULAR AGENDA RULEMAKING HEARING 

### Regulation Number 10: Criteria for Conformity The Commission considered streamlining the transportation conformity process by allowing the Colorado Air Pollution Control Division to provide concurrence with routine transportation conformity determinations without the need for a public hearing before the Colorado Air Quality Control Commission. This change to the conformity process is allowed for under federal law and will reduce the burden on the Commission, the Division and transportation planning organizations while ensuring that air quality requirements are met. The Commission also considered proposed revisions to the SIP, AQCC's Regulation Number 10 and the Procedural Rules. The Commission discussed how public concerns would be addressed or brought forward to the Commission. Allison noted that this could be discussed during the Director's Report as occurrences happened.

Motion:

Moved: Second: Discussion: Carried: To adopt the revisions to Regulation Number 10 and the Commission's Procedural Rules regarding conformity, as presented by the Division with the amended Statement of Basis, Specific Statutory Authority and Purpose for Regulation Number 10, and to correct the typographical error identified by the Division. In addition, the Commission directs that the Lead Planning Agency definition in Regulation Number 10 be revised to eliminate confusing language and errors. Commissioner Slutsky Commissioner Wilson
none 6-0

2BRIEFINGS, DISCUSSIONS AND REPORTS 

### Rocky Mountain National Park (RMNP) The Division, National Park Service, and Environmental Protection Agency have been working together on the RMNP Initiative, a collaborative effort to reduce nitrogen deposition in Rocky Mountain National Park. Lisa Clarke of the Division introduced Susan Johnson-Policy Analyst of the Air Resources Division NPS, Carol McCoy-Chief of the Air Resources Division NPS, Jim Cheatham-Biologist for the RMNP, and John Mack-Chief of Natural Resources for the RMNP. Clarke and Mack briefed the Commission on the progress of the tasks outlined in the Nitrogen Deposition Reduction Plan endorsed by the Commission in 2007 and the Contingency Plan adopted in 2010, as well as recent activities of the MOU agencies. Clarke provided a handout to the Commission and noted that the attachments helped illustrate the activities of the RMNP Agriculture subcommittee. The Commission received public comment from Robert Collier representing the Environmental Defense Fund. HB09-1199: Colorado Healthy Forests and Vibrant Communities Act As a follow-up to the Commission's request from the March 2011 briefing, Pat McLaughlin of the Division provided the Commission a status update regarding implementation of the recommendations from the HB09-1199 study. McLaughlin described the Division's prescribed fire efforts, the innovations and program improvements implemented this past year, and the steps going forward. Deputy Regional Forester Brian Ferebee of the Rocky Mountain Region US Forest Service lead the USFS's presentation and was assisted by Glenn Casamassa- Forest Supervisor for the Arapaho-Roosevelt National Forest and the Pawnee National Grassland, Paul Langowski- regional Branch Chief for Fuels and Fire Ecology, Jeff Sorkin- Air Program Manager for this region and the Intermountain Region of the US Forest Service and Cheri Ford who serves as a liaison between the Forest Service and Colorado. Casamassa presented a status update to the Commission on collaborative efforts with the Division regarding changes to the Colorado Smoke Management Program since the March 17, 2011 Commission hearing. Casamassa noted that to be successful there was a need to move forward on a more objective and transparent permitting process that allows for an appropriate increase in prescribed fire and to develop an approach to smoke management that considers both protection of public health and the needs of Coloradans for reduced hazardous fuels in our forests. Ferebee noted that they would like to provide the Commission with semi-annual updates and some field tours if they're interested. The Commission conducted business during the lunch hour with a discussion about their strategic planning process with LEAN consultant Barbara Shecter and Roz Bedell Operations Director for CDPHE.

REGIONAL AIR QUALITY COUNCIL (RAQC) REVIEW 

### Ken Lloyd briefed the Commission regarding the strategy tables that were discussed and approved at the RAQC's November meeting. Lloyd noted that even though additional mandatory measures as part of a federally-enforceable SIP were not required at this time in the Denver/North Front Range nonattainment area, the region still faced a challenge to achieve the 2008 standard by 2015 and additional short-term actions would be prudent to ensure attainment.

3

### Lloyd noted that additional measures would likely be needed beyond the 2015-2020 timeframe in order to maintain attainment with the current standard and address a possible more stringentstandard in the future and in light of the need to continue ozone reduction measures in the shortterm, the RAQC asked its various strategy subcommittees to reconvene, review the listed strategies already developed, and identify recommended short-term activities and actions. Monitoring Briefing The Division briefed the Commission on monitoring sites operated by the Division and others. The briefing addressed EPA monitoring and siting requirements, why sites are located in certain places and not in others, what pollutants are monitored, and possibilities for additional monitoring. New monitoring requirements from EPA were also addressed and the Division's current plans to meet those requirements. Jannette Whitcomb, Environmental Manager with the City of Aspen monitored the briefing via conference call.
Commissioner Informational Items Coons discussed EPA Advisory Committee meeting issues: nutrient standards guidance process — Colorado is on the forefront; wildfire and prescribed burns in terms of exceptional events; mercury legislation and how it will impact Colorado; formal resolution and concerns about ozone setback — what does that do to credibility; interagency collaboration; formal resolution/approval agency-wide effort to incorporate environmental impacts; and water subcommittee getting briefing regarding fracking. Slutsky toured the JBS Five Rivers Cattle Feeding to see how their gasifier turns manure into energy. Basically, the system burns feedlot manure to produce heat that is in turn used to produce steam energy Division Director's Report

— 

### Will Allison

• Received letter from EPA for nonattainment area and approval of exact boundaries proposed

• EPA moving forward with proposal for oil and gas NSPS — green completions being the most important

• OGCC released fracking rules and must disclose chemicals/chemical families

• EPA is coming out with new guidance on how to handle SO2

• Rocky Mountain Steel Mill permit finalized

• WildEarth Guardians seeking EPA nonattainment designations for PM exceptional events

• EPA to finalize its utility MACT 

### Attorney General's Report

— 

### Andrea Gelfuso-Goetz

• CMA CORA — courts have decided that emails are confidential

• CMA vs. Urbina — brief scheduled for March

• Climate Change case was won — no public trust in air Administrator's Report

— 

### Mike Silverstein

• Review February and March agenda items

• Review of Action Items from today's Commission meeting

• Informed Commission that review of the Procedural Rules would begin in March

• Update on the Commission website redevelopment would occur at the February meeting Adjourn at 3:35 PM
4

# Legal Opinion of the Colorado State Attorney General 40 CFR Part 51 Appendix V 2.1(c) and (e)JOHN W. SUTHERS Attorney General CYNTHIA H. COFFMAN Chief Deputy Attorney General DANIEL D. DOMENICO Solicitor General 

### STATE OF COLORADO DEPARTMENT OF LAW
OFFICE OF THE ATTORNEY GENERAL STATE SERVICES BUILDING 1525 Sherman Street - 7th Floor Denver, Colorado 80203 Phone (303) 866-4500 Fax (303) 866-5691

Tracking Number: 2011

- 00670

OPINION OF THE ATTORNEY GENERAL RENDERED IN

CONNECTION WITH THE RULES ADOPTED BY THE Air Quality Control Commission ON 12/15/2011

5 CCR 1001-14 AIR QUALITY STANDARDS, DESIGNATIONS AND EMISSION BUDGETS
The above-referenced rules were submitted to this office on 12/16/2011 as required by section 24-4-103, C.R.S. This office has reviewed them and finds no apparent constitutional or legal deficiency in their form or substance.

December 22, 2011 14:47:07 MST

JOHN W. SUTHERS Attorney General by DANIEL D. DOMENICO Solicitor General

# Regulation or Regulation Revisions as Published in the Colorado Code of Regulations (this is the version that is published by Lexis Nexis) 

# 40 CFR Part 51 Appendix V 2.1(b)

# DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT

AIR QUALITY CONTROL COMMISSION


## AIR QUALITY STANDARDS, DESIGNATIONS AND EMISSION BUDGETS

5 

### CCR 1001-14
EDITOR'S NOTES*
Authority Cited: 24-4-103; 25-7-108, -110, -110.5, -110.8, -201, -209, C.R.S. History and Amendments: Amended 09/11/77, 1 CR 1. Added 05/25/78, 1 CR 6. Amended 12/14/78, 2 CR 1. Amended 04/12/79, 2 CR 5. Redesignated 08/23/79, 2 CR 9. Adopted 12/20/79, effective 1/30/80, 3 CR 1. Amended 03/27/80, effective per approval by the General Assembly, 3 CR 5. Adopted 03/10/83, effective 4/30/83, 6 CR 4. Adopted 10/17/83, effective 11/30/83, 6 CR 11. Repealed 07/20/89, effective 08/30/89, 12 CR 8. Adopted 12/21/89, effective 01/01/93, 13 CR 2. Adopted as emergency regulation 02/21/91, effective 02/21/91, 14 CR 4. Adopted as emergency regulation 05/16/91, effective 05/16/91, 14 CR 6. Adopted 06/20/91, effective 07/30/91, 14 CR 7. Adopted 06/16/92, effective 07/30/92; Visibility Standard adopted 08/20/91, effective 01/01/93, 15 CR 7. Visibility Standard effective date postponed on an emergency basis 12/17/92, postponement effective 12/17/92; Visibility Standard effective 01/01/95, 16 CR 1. Adopted 03/18/93, effective 01/01/95, 16 CR 4. Adopted 06/24/93, effective 08/30/93, 16 CR 8. Adopted 09/22/94, effective 11/30/94, 17 CR 11. Adopted 02/16/95, effective 04/30/95, 18 CR 4. Adopted 06/15/95, effective 08/30/85, 18 CR 8. Adopted 03/21/96, EFFECTIVE 05/30/96, 19 CR 5. Adopted 09/19/96, EFFECTIVE 11/30/96, 19 CR 11. Adopted 10/17/96, EFFECTIVE 12/30/98, 19 CR 12. Adopted 12/18/98, EFFECTIVE 03/02/98, 21 CR 2. Adopted 01/15/98, EFFECTIVE 03/30/98, 21 CR 3. Adopted 09/17/98, EFFECTIVE 11/30/98, 21 CR 11. Adopted 01/10/00, EFFECTIVE 03/01/00, 23 CR 2. Adopted 02/17/00, EFFECTIVE 04/30/00, 23 CR 4. Adopted 03/16/00, EFFECTIVE 05/30/00, 23 CR 5. Adopted 01/11/01, EFFECTIVE 03/02/01, 24 CR 2. Adopted 04/19/01, EFFECTIVE 06/30/01, 24 CR 6. Adopted 11/15/01, EFFECTIVE 12/30/01, 24 CR 12. Adopted 07/18/02, EFFECTIVE 09/30/02, 25 CR 9. Adopted 12/19/02, EFFECTIVE 03/02/03, 26 CR 2. Sections V through VII Adopted 06/19/03, EFFECTIVE 08/31/03, 26 CR 8. Parts V through VII Adopted 12/18/03, EFFECTIVE 03/01/04, 27 CR 2. Parts III.F, III.M , VIII.S adopted 03/12/04, EFFECTIVE 05/31/04, 27 CR 5.

A.G. Opinions: I AG 241; 2 AG 15; 2 AG 113; 2 AG 225; 3 AG 19; 3 AG 122; 6 AG 110-111; 8 AG 328; 13 AG 53; 14 AG 118; 14 AG 193; 14 AG 225; 15 AG 256; 16 AG 23; 16 AG 114; 16 AG 278; 17 AG 423; 18 AG 148; 18 AG 286; 19 AG 130; 19 AG 338; 19 AG 389; 21 AG 48; 21 AG 86; 21 AG 353; 23 AG 44; 23 AG 99; 23 AG 116; 24 AG 60-60A; 24 AG 168; 24 AG 364; 25 AG 314; 26 AG 73; 26 AG 332; 27 AG 81; 27 AG 174;

Annotations: Rule 16(c)(3)(b) and 16(c)(3)(c) was not extended by Senate Bill 92-132 and therefore expired June 1, 1992.
*This Title Page does not constitute an official part of any regulation. Information contained on the Title Page is provided by the Publisher from sources deemed reliable and is solely for informational and historical purposes. See cautionary note in Introductory Materials, How to Use the CCR.
C 2012 State of Colorado All Rights Reserved. (800) 833-9844EDITOR'S NOTES (continued) History and Amendments: Parts III.E, III.M, VIII.T adopted 12/16/04, EFFECTIVE 03/02/05, 28 CR 2. Pp. 20-21, 59-60 adopted 12/15/05, EFFECTIVE 03/02/06, 29 CR 2. Rule replaced in its entirety, adopted 11/20/08, EFFECTIVE 12/30/08, 31 CR 12. Rule replaced in its entirety, adopted 12/12/08, EFFECTIVE 01/30/09, 32 CR 1. Rules V.A, VIII.X, VIII.Y, adopted 11/19/09, EFFECTIVE 12/30/09, 32 CR 12. Rule replaced in its entirety, adopted 03/18/10, EFFECTIVE 05/15/10, 33 CR 9. Rule V.A.1 [TN 2010-00855] adopted 12/16/10, EFFECTIVE 03/01/11, 34 CR 2. Rule V.A.1, VIII.BB [TN 2011-00670] adopted 12/15/11, EFFECTIVE 01/30/12, 35 AG 1.

A.G. Opinions: 28 AG 46;29 AG 80; 31 AG Dec 1001-14; 32 AG Jan 1001-14; 32 AG Dec 1001-14 — 1001-14a; 33 AG Apr 1001-14; 34 AG Feb 1001-14; 35 AG Jan 1001-14

Annotations:

5 CCR 1001-14 Page 2© 2012 State of Colorado 35 CR 1 and 2, 01-12 Page 21 All Rights Reserved

V. Emission Budgets for Attainment/Maintenance Areas in the State of Colorado
V.A. Budgets V.A.1. The following Motor Vehicle Emission Budgets shall be utilized to assess the conformity of Transportation Plans, TIPs, and where appropriate, Projects, for the applicable periods and geographic areas indicated:

Denver Attainment/Maintenance PM10: 2015 through 2021: 54 tons/day; 2022 and beyond: 55 Area (Modeling Domain) tons/day. Nitrogen Oxides: 2015 through 2021: 70 tons/day; 2022 and beyond: 56 tons/day Trading provisions: Trading of PM10 for NOx, or NOx for PM10to adjust emission budgets for purposes of demonstrating transportation conformity shall be allowed using the emission trading formula as follows: For trades necessary to increase a primary PM10 budget, 15.0 tons/day of NOx will be taken from the NOx budget to increase the primary PM10 budget by 1.0 tons/day, a ration of 15 to 1. For trades necessary to increase a NOx budget, 1.0 tons/day of primary PM10 will be taken from the primary PM10 budget to increase the NOx budget by 12.0 tons/day, a ratio of 1 to 12. Implementation of trading provisions: In the event the MPO cannot demonstrate consistency with the specific PM10 and NOx mobile source emission budgets, the trading provisionsmay be utilized only after the MPO has considered all reasonably available local control measures to meet the budgets. The MPO must demonstrate the need for trading through the usualconsultation procedures for state implementation plan development delineated in Section IV (F) of AQCC Regulation Number 10, Criteria for Analysis of Conformity.If trading is utilized, the MPO shall include the following information in the transportation conformity determination: (1) The budget for primary PM 10 and NOx for each required year of the conformity determination, before trading is employed; (2) The portion of the original budget to be used to supplement a wanting budget, for each required year for the conformity determination; (3) The increased budget that resultsfrom trading, along with relevant calculations, and (4) the resulting primary PM10 and NOx budgets for each required year of the conformity demonstration.The MPO shall then compare projected emissions to the adjusted PM10 and NOx motor vehicle emission budgets to demonstrate conformity.

CODE OF COLORADO REGULATIONS 5 CCR 1001-14Page 22

Denver Attainment Maintenance Ozone Precursors (attainment/maintenance area boundary) Area NOx 2002 and beyond 134 tpsd VOC 2002 and beyond 119tpsd (tpsd = tons per summer day) Carbon Monoxide (attainment/maintenance area boundary) 2013 through 2020: 1625 tons/day; 2021 and beyond: 1600 tons/day.
Denver Metro Area/North Front Regional Emissions Budgets

Range 8-Hour Ozone NonatNOx: 122.9 tons/day tainment Area VOCs: 109.2 tons/day Southern Sub-Regional Emissions Budgets NOx: 102.4 tons/day VOCs: 89.7 tons/day Northern Sub-Regional Emissions Budgets NOx: 20.5 tons/day VOCs: 19.5 tons/day

Aspen Attainment/Maintenance PM10 2023 and Beyond: 1,146 lbs./day Area Carlon City PM10 2020 and Beyond: 1,613 lbs./day Lamar (Modeling Area) PM10 2015 and Beyond: 7,534 lbs./day Pagosa Springs (Modeling Area) PM10 2021 and Beyond: 946 lbs./day

Steamboat Springs (Modeling Area) PM10 2015 through 2023: 21,773 lbs./day PM10 2024 and Beyond: 1,103.2 lbs./day Telluride (Modeling Area) PM10 2021 and Beyond: 1,008 lbs./dayLongmont Attainment/Maintenance Area Carbon Monoxide 2010 through 2014: 43 tons/day 2015-2019: 43 tons/day 2020 and Beyond: 43 tons/dayColorado Springs Attainment/Maintenance Area Carbon Monoxide 2010 and Beyond: 531 tons/day

Ft. Collins Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 99 tons/day2010 through 2014: 98 tons/day2015 and Beyond: 94 tons/dayGreeley Area Attainment/Maintenance Area Carbon Monoxide 2005 through 2009: 63 tons/day2010 through 2014: 62 tons/day2015 and Beyond: 60 tons/day

5 CCR 1001-14 CODE OF COLORADO REGULATIONS© 2012 State of Colorado 35 CR 1 and 2, 01-12 Page 57 All Rights Reserved In the absence of clearly defined geographic "Category" areas in rule, the Colorado "Category I, II andIII" incremental standards that remain in the Ambient Air Quality Standards Regulation cannot be applied in practice. While this proposal removes the state-only SO2 incremental standards, this changedoes not undermine existing protection for Colorado Federal Class I and II areas, or for those additional Colorado national monuments and forest service primitive areas currently granted Class I protection in Regulation Number 3. For these reasons, these state-only SO2 PSD increments should be removed from regulation. Reorganize, Clarify and Make Typographical, Grammatical, and Formatting CorrectionsThe remaining proposed revisions to reorganize and rename the regulation, identify existing standards as state-only, identify missing CO and PM10 attainment/maintenance effective dates in tables,revise the 1-Hour Ozone Attainment/Maintenance Map title to clarify association with the 1-hour standard only, and make typographical, grammatical and formatting corrections, as necessary, are purely administrative in nature, and not believed to have any economic impact. Findings pursuant to C.R.S. §§ 110.5(5)(a) and 110.8 These revisions eliminate PSD SO2 increments that would be more stringent than federal increments if they had been fully implemented. Because there are no currently designated areas to which the more stringent standards would apply, these standards cannot be implemented. Therefore, these revisions do not exceed or differ from the federal act or rules. These revisions align the increments in question with federal increments. The federal increments arebased on reasonably available, validated, reviewed and sound scientific methodologies. These revisions are not intended to reduce air pollution and do not result in a demonstrable reduction in air pollution. Public health and the environment are sufficiently protected by the national increments. These revisions benefit the government, regulated community and the public by eliminating confusion caused by differences between state and federal requirements. VIII.AA Aspen PM10 Adopted: December 16, 2010 The amendments to the "Ambient Air Quality Standards for the State of Colorado" Regulation adopted by the Commission establish mobile source emissions budgets for the Aspen area. Federal Requirements Nothing in this rule change exceeds the minimum requirements of the federal act. Statutory Authority The authority to establish emissions budgets and to establish criteria for transportation conformity determinations is included in the general authority to adopt a State Implementation Plan set out in Section 25-7-105(1), C.R.S. (2001). Findings pursuant to Section 25-7-110.8The mobile source emissions budgets are based on EPA's MOVES2010 emissions model and EPAapproved methods for calculating fugitive dust emissions as required by federal regulations. All methodologies and information made available by interested parties have been considered. The emissions budgets reduce the potential for air pollution by capping emissions from mobile sources. In adopting this rule, the Commission chose the most cost-effective alternative.

CODE OF COLORADO REGULATIONS 5 CCR 1001-14Page 58

VIII.BB.Steamboat Springs
Adopted: December 15, 2011 Basis and Purpose The purpose of this amendment is to update the PM10 emission budget for the Steamboat Springs area in connection with the adoption of the Revised PM10 Maintenance Plan for the Steamboat Springs Attainment/Maintenance Area. Specific Statutory Authority The Commission promulgates this regulatory change pursuant to its authority under Section 25-7- 105(1)(a)(1), C.R.S. to adopt a comprehensive state implementation plan that meets the requirements of the federal Clean Air Act. Findings Pursuant to Section 25-7-110.8 The mobile source emission budgets are based on EPA-approved methods for calculating PM10 emissions as required by federal regulations. All methodologies and information made available by interested parties have been considered. The emission budgets reduce the potential for air pollution by capping emissions from mobile sources. In adopting this rule, the Commission chose the most cost-effective alternative.

5 CCR 1001-14 CODE OF COLORADO REGULATIONS