Grants Pass Carbon Monoxide 

Limited Maintenance Plan

Submitted to: U.S. Environmental Protection Agency

By: State of Oregon Department of Environmental Quality

April 2015

 

 

DEQ Environmental 

Solutions

Air Quality Program

811 SW 6th Avenue

Portland, OR 97204

Phone: (503) 229-5696

(800) 452-4011

Fax: (503) 229-6762

Contact: Brian Finneran

www.oregon.gov/DEQ

DEQ is a leader in 

restoring, maintaining and 

enhancing the quality of 

Oregon’s air, land and 

water.
 

State Implementation Plan Revision

Grants Pass Carbon Monoxide Limited Maintenance Plan

A Limited Maintenance Plan

for Carbon Monoxide

The Grants Pass Urban Growth 

Boundary

State of Oregon Clean Air Act 

Implementation Plan

Adopted by the Environmental Quality Commission on

April 16, 2015

State of Oregon

Department of Environmental Quality

811 SW Sixth Avenue

Portland, OR 97204-1390
Table of Contents

Acknowledgments............................................................................................................................ i

Executive Summary........................................................................................................................ ii

Plan Structure................................................................................................................................. iii

1. Introduction.................................................................................................................................1

2. Geographic Area .........................................................................................................................1

3. History of CO Problem in Grants Pass.......................................................................................2

4. Limited Maintenance Plan Option..............................................................................................4

5. Emission Inventory .....................................................................................................................4

6. Continuing Control Measures.....................................................................................................6

7. Contingency Plan........................................................................................................................8

8. Verification of Continued Attainment ........................................................................................9

Table of Figures

Figure 1. Grants Pass UGB and location of the CO Monitoring Station....................................... 2

Figure 2. Grants Pass Carbon Monoxide Trend 2nd highest 8-hour average, 1980-2005.............. 4

Figure 3. 2005 Grants Pass Annual CO Emissions........................................................................ 6

Figure 4. 2005 Grants Pass Season CO Emissions........................................................................ 6

Table of Tables

Table 1. Grants Pass Carbon Monoxide Concentrations 1980-2005............................................. 3

Table 2. 2005 Grants Pass UGB CO Annual and Seasonal Emission Inventory .......................... 5

Appendices

Appendix A: EPA 1995 Paisie Memo

Appendix B: Grants Pass 2005 Emission Inventory

Appendix C: EPA 2006 Approval Letter for removal of the CO monitor

Appendix D: Inventory Preparation and Quality Assurance Plan

Grants Pass Carbon MonoxidePM10 Limited Maintenance Plan
Acknowledgments

Principal Author: Brian Finneran, DEQ Air Quality Planning 

Principal Contributors:

Oregon Department of Environmental Quality

David Collier Air Quality Planning Manager

Aida Biberic Air Quality Planning

Anthony Barnack Air Quality Planning

Wes Risher Air Quality Technical Services

Chris Swab Air Quality Technical Services

Environmental Protection Agency

Lucy Edmondson EPA Region X

Claudia Vaupel EPA Region X

Bob Kotchenruther EPA Region X

Grants Pass

Dan Moore Rogue Valley Council of Governments

Jonathan David Rogue Valley Council of Governments

Other support:

Tom Carlson Sierra Research, Inc

Grants Pass Carbon Monoxide Limited Maintenance Plan Page i
Executive Summary

The City of Grants Pass and surrounding area currently meets the federal standard for Carbon 

Monoxide (CO). This State Implementation Plan (SIP) revision explains how this area will 

continue to meet this standard through 2025. EPA set the national ambient air quality standard 

for carbon monoxide at 35 parts per million (ppm) for a 1-hour average and 9 ppm for an 8-hour 

average. Like most areas of the country that failed to meet the carbon monoxide standard, 

Grants Pass did not meet the 8-hour portion of the standard. 

Grants Pass was designated a nonattainment area for carbon monoxide on December 15, 1985 

and classified as moderate upon enactment of the Clean Air Act Amendments in 1990. The 

downtown central business district represented the nonattainment area. The highest 8-hour CO

concentration recorded in Grants Pass occurred in 1982 at level of 14.4 ppm. In that same year, 

Grants Pass exceeded the federal 8-hour standard of 9 ppm on 28 days. The 1-hour standard has 

never been exceeded in Grants Pass. By the late 1980’s, maximum levels were closer to the level

of the standard, and the last exceedance was in 1990. 

The area was reclassified to attainment for the 8-hour CO standard in August 2000 when EPA 

approved the first maintenance plan designed to maintain compliance with the 8-hour CO

standard through the year 2015 (see 65 FR 52932). While the central business district

represented the maintenance area, EPA considered the Urban Growth Boundary to be a more 

representative area of influence for carbon monoxide emissions, and the 1993 emission inventory 

was prepared for UGB. The carbon monoxide monitor was located at 215 SE Sixth Street, 

known as the Wing Building. Measured CO levels were so low that the monitor was removed 

(with EPA approval) in 20061

. A second maintenance plan is now required, and once approved 

by EPA, will apply until 2025, and fulfill the final maintenance planning requirements under the 

Clean Air Act. 

Grants Pass qualifies for a Limited Maintenance Plan (LMP), which is an option EPA provides 

for areas at low risk of exceeding the CO standard (see EPA 1995 Paisie Memo in Appendix A). 

The current 8-hour CO design value for the Grants Pass area is 4.0 ppm based on the two most 

recent years of data (2004-2005), which is well below the standard. According to the LMP 

guidance, EPA will consider the maintenance demonstration satisfied if the monitoring data 

show the design value is at or below 7.65 ppm, or 85 percent of the level of the 8-hour CO 

standard. 

To qualify for the LMP approach, the control and contingency measures from the first Grants 

Pass CO maintenance plan must remain in place. The primary control measure has been the 

emission standards for new motor vehicles under the Federal Motor Vehicle Control Program. 

Another measure has been the New Source Review Program with Best Available Control 

Technology (BACT).

1 See Appendix C: EPA approval letter dated October 19, 2006, to Anthony Barnack, DEQ Air Monitoring Program, 

on discontinuing the Grants Pass CO monitor. 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page ii

 
To quantify carbon monoxide emission sources in Grants Pass, DEQ used the EPA 2005 

National Emission Inventory (NEI) for this plan. Since that the Grants Pass CO monitor was 

removed in 2006, to verify continued attainment with the CO standard, DEQ will track CO 

emissions every three years as part of the Statewide Emission Inventory, which is submitted to 

EPA for inclusion in the NEI. DEQ will review the NEI estimates to identify any increases, 

focusing on on-road mobile sources, which represent about 70% of the CO emissions in Grants 

Pass. Any emissions increase will be evaluated by DEQ to verify it is not due to a change in 

emission calculation methodology or other factors not representative of an actual emissions 

increase. For the purposes of triggering the Contingency Plan, an increase of 5 percent in either 

the total annual or season emissions, or the on-road mobile source category, will be considered 

as “significant” for triggering the contingency measures. These include resuming ambient CO 

monitoring in Grants Pass, and if needed, forming an advisory committee to develop new 

strategies to prevent or correct any violation of the CO standard, and replacing BACT with 

LAER control technology for industrial sources.

Plan Structure

This SIP revision includes the compliance history for Grants Pass and describes how the

area met and will continue to meet the standard.

This document is organized as follows:

Section 1 – Introduction. Describes the purpose of this second maintenance plan, and summary 

on the CO standard. 

Section 2 – Geographic Area. Describes the geographic area covered by the maintenance plan,

Section 3 – History of the Carbon Monoxide Problem. Summarizes Grants Pass CO compliance 

history and past CO monitoring data and trends.

Section 4 – Limited Maintenance Plan Option. Describes the criteria an area must meet to

qualify for this option and how Grants Pass qualifies.

Section 5 – Emission Inventory. Includes historical information on the most significant CO 

emission categories from the original maintenance plan and an updated inventory on these

categories.

Section 6 – Continuing Control Measures. Lists the measures that were in the original CO 

maintenance plan, and how these measures will be continued under this LMP. 

Section 7 – Contingency Plan. Describes the contingency measures that apply should a violation 

occur in the future.

Section 8 – Verification of Continued Attainment. Describes how compliance will be tracked 

and confirmed.

Appendices – Supporting documentation for this LMP. 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page iii
1. Introduction

This State Implementation Plan revision explains how the Grants Pass carbon monoxide (CO)

maintenance area, as defined in OAR 340-204-0010 (the Grants Pass UGB) will continue to 

meet the National Ambient Air Quality Standard (NAAQS) for CO through 2025. This plan 

represents a “limited” maintenance plan, developed in accordance with the federal Clean Air Act 

and the policies of the U.S. Environmental Protection Agency (EPA) (see Appendix A 1995 

Paisie Memo). 

The Clean Air Act requires EPA to set air quality standards to protect public health for six 

common air pollutants, including carbon monoxide. In 1971 EPA set the national ambient air 

quality standard for carbon monoxide. Carbon monoxide is a colorless, odorless gas that 

decreases the oxygen carrying capacity of the blood. High concentrations can severely impair 

the function of oxygen-dependent tissues, including the brain, heart, and muscle. Prolonged 

exposure to even low levels can aggravate existing conditions in people with heart disease or 

circulatory disorders. Motor vehicles are the primary source of CO in Oregon.

EPA established the national ambient air quality standard for CO at 35 parts per million (ppm) 

for a 1-hour average and 9 ppm for an 8-hour average. Two exceedances within one calendar 

year constitute a violation. Like most areas of the country that failed to meet the CO standard, 

Grants Pass did not meet the 8-hour portion of the standard2

. 

2. Geographic Area

The City of Grants Pass is located in southwestern Oregon, on the western side of the Cascade 

Mountains, in the Rogue Valley, northwest of Medford and along the Rogue River. The city is 

approximately 11 sq. miles in area, and the US Census 2013 population was 35,076. The 

surrounding hills can trap air pollution under stable meteorological conditions (inversions). 

These conditions exist most frequently during the winter and are associated with the majority of 

carbon monoxide violations. 

Figure 1 shows the Grants Pass central business district, which is the maintenance area, and the 

Grants Pass UGB, which is the geographic area subject to this limited maintenance plan. Inside 

the central business district is the location of the monitoring station, at 215 SE Sixth Street. This 

district is defined by “B street” to the north, 8th street to the east, “M” street to the south, and 5th

street to the west.

2 40CFR part 50.8 states that standards defined in parts per million should be compared “in terms of integers with 

fractional parts of 0.5 or greater rounding”. This led to an interpretation by EPA that any 8-hour CO concentration 

of less than 9.5 ppm would be equivalent to attainment. Therefore, concentrations at or above 9.5 ppm represent an 

exceedance of the standard. Two exceedances in one calendar year constitute a violation.

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 1

 
Figure 1. Grants Pass UGB and location of the CO Monitoring Station

3. History of CO Problem in Grants Pass

DEQ began monitoring carbon monoxide in Grants Pass in 1980. The monitor was located at 

215 SE 6th Street, known as the Wing Building, and has remained at that location until it was 

removed in 2006.

3

 A saturation survey conducted during the winter of 1993-1994 confirmed this 

location to be the best location for monitoring “worst case” CO concentrations. 

A violation of the carbon monoxide standard occurs when there are two exceedances within one 

calendar year. The highest 8-hour CO concentration recorded in Grants Pass occurred in 1982 at 

level of 14.4 ppm. In that same year, Grants Pass exceeded the federal 8-hour standard of 9 ppm 

on 28 days. The 1-hour standard has never been exceeded in Grants Pass. 

In 1985, the Grants Pass Central Business District was designated by EPA as a nonattainment 

area for carbon monoxide. By the late 1980’s, maximum levels were closer to the standard level, 

and the last exceedance was in 1990. 

3 See Appendix C: EPA approval letter dated October 19, 2006, to Anthony Barnack, DEQ Air Monitoring Program, 

on discontinuing the Grants Pass CO monitor in 2006. 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 2

 
DEQ submitted a CO maintenance plan in November 1999, which EPA approved on August 

2000 (65 FR 52932), and resulted in Grants Pass being reclassified to attainment with the carbon 

monoxide standard. The maintenance plan was to maintain compliance with the 8-hour carbon 

monoxide standard through the year 2015. While the central business district represented the 

maintenance area, EPA considered the Urban Growth Boundary to be a more representative of 

the area of influence for carbon monoxide emissions, and the 1993 emission inventory was 

prepared for UGB. 

The trend in carbon monoxide levels, as recorded at the Wing Building monitor in downtown 

Grants Pass, is shown below in Table 1 and Figure 2. Since a violation is triggered by two 

exceedances in a calendar year, Figure 2 shows only the second highest concentration trend. 

Measured CO levels were so low that the monitor was removed with EPA approval in 2006 (the 

last full year of data is 2005). 

Table 1. Grants Pass Carbon Monoxide Concentrations 1980-2005

8-hour CO Averages

Year Maximum 2nd Highest

1980 13.3 12.7

1981 11.6 11.5

1982 14.4 13

1983 12.3 11.3

1984 12.9 11.2

1995 11.7 11.4

1996 10.4 10.2

1987 10.1 9.7

1988 10.8 10.4

1989 9.6 9.2

1990 9.9 8.5

1991 9.2 9.1

1992 8.3 7.4

1993 7.7 7.1

1994 6.6 6

1995 7.2 6.3

1996 6.4 6

1997 5.3 5

1998 4.7 4.7

1999 5 4.6

2000 4.5 4.3

2001 5.5 4.7

2002 4.6 4.5

2003 3.9 3.9

2004 4 3.5

2005 3.9 3.6

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 3
Figure 2. Grants Pass Carbon Monoxide Trend 2nd highest 8-hour average, 1980-2005

0

2

4

6

8

10

12

14

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

PPM

Year

8-Hour Standard

Second Highest Value 

4. Limited Maintenance Plan Option

EPA developed the Limited Maintenance Plan (LMP) option for areas with little risk of reviolating the carbon monoxide standard (see 1995 Paisie Memo, Appendix A). EPA allows 

states to use this policy to prepare the required second 10-year maintenance plans, if the 

monitoring data show the design value is at or below 85 percent of the 8-hour CO standard, or 

7.65 ppm. Determining the design value in this case is based on the higher of the two annual 

second highs in a two year calendar period. The Grants Pass 8-hour design value is 4.0 ppm,

based on the two most recent years of data (2004-2005). This is well below both the 8-hour 

standard and the 85 percent level, so the area is eligible for the LMP option.

The LMP approach does not require future year emission projections or a maintenance 

demonstration. A LMP must include an attainment inventory, provisions for verification of 

continued attainment, a contingency plan and a statement regarding conformity determinations. 

Due to the low measured CO values in Grants Pass over the past 20 years, DEQ does not 

anticipate that CO levels will approach levels that would violate or exceed the 8-hour CO 

standard, and as noted above, has never exceeded the 1-hour CO standard.

5. Emission Inventory

This section presents the emissions inventory for the second 10-year maintenance plan and 

briefly describes its development. The LMP Guidance requires that the maintenance plan include 

an inventory with emission levels consistent with attainment of the CO standard. An inventory 

preparation and quality assurance plan (IPP) for the Grants Pass UGB was submitted to EPA in 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 4
March 2014, and is provided in Appendix D. EPA reviewed the plan and agreed that the 

inventory be developed using EPA’s 2005 National Emission Inventory (NEI) data for Josephine 

County. In accordance with requirements for the LMP option, no emission projections were 

calculated. 

Historically, exceedences of the CO 8-hour standard in Grants Pass have occurred during the 

winter months, when cooler temperatures contribute to incomplete combustion, and when CO 

emissions are trapped near the ground by atmospheric inversions. As noted in Section 3, the

UGB was used for the initial 1993 emission inventory since it was more representative of the 

area of influence for carbon monoxide emissions, and used again for the 2005 emission 

inventory in this LMP. Sources of carbon monoxide in Grants Pass include industry, motor 

vehicles, non-road mobile sources, (e.g., construction equipment, recreational vehicles, lawn and 

garden equipment, and area sources (e.g., outdoor burning, woodstoves, fireplaces, and 

wildfires). The CO season is defined as three consecutive months - December 1 through the end 

of February. As such, season day emissions in addition to annual emissions are included in the 

inventory. The unit of measure for annual emissions is in tons per year (tpy), while the unit of 

measure for season emissions is in pounds per day (lb/day). In addition, the county-wide EI data 

is spatially allocated to the Grants Pass UGB, and to buffers around the UGB, depending on 

emissions category. 

The 2005 carbon monoxide emission inventory for Grants Pass is summarized in Table 2 and 

Figures 3 and 4 below. The largest category of CO emissions is onroad mobile sources

(primarily passenger cars and trucks). Considerably less are area sources (mostly residential 

wood combustion) and non-road engine sources (highest of these being commercial, industrial, 

and construction equipment, and lawn and garden equipment). The most significant difference 

between annual and seasonal emissions is that area sources during the winter season are higher 

(due to increased residential woodstove use), yet still much less than onroad mobile sources. 

While vehicle emission rates have declined steadily over preceding decades, the fact that cars 

and trucks tend to be operated close together and can create areas of traffic congestion, makes 

this source category the most likely to produce the highest CO concentrations. 

A detailed breakdown of the 2005 CO emission inventory is provided in Appendix B. 

Table 2. 2005 Grants Pass UGB CO Annual and Seasonal Emission Inventory

Source Category

CO Emissions

Annual 

Tons / Year

Annual 

percent

Season 

Lbs / Day

Season 

percent

Stationary Point Sources 207 1% 1,202 1%

Stationary Area Sources 2,461.3 16% 22,244 25%

Non-Road Engine Sources 1,718.2 11% 6,289 7%

On-Road Mobile Sources 10,603.3 71% 58,120 66%

Total 14,989.7 100% 4,826 100%

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 5
Figure 3. 2005 Grants Pass Annual CO Emissions

 

Figure 4. 2005 Grants Pass Season CO Emissions

6. Continuing Control Measures

To qualify for the LMP option, the control measures from the first CO maintenance plan must 

remain in place and unchanged. The primary control measure has been the emission standards 

for new motor vehicles under the Federal Motor Vehicle Control Program. Other control 

measures have been the New Source Review Program, and several residential woodsmoke 

emission reduction efforts.

0

2,000

4,000

6,000

8,000

10,000

12,000

Stationary

Point Sources

Stationary

Area Sources

Non-Road

Mobile

Sources

On-Road

Mobile

Sources

tons/year

0

10,000

20,000

30,000

40,000

50,000

60,000

Stationary

Point Sources

Stationary

Area Sources

Non-Road

Mobile

Sources

On-Road

Mobile

Sources

lbs/day

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 6
Federal Motor Vehicle Emission Control Program

This limited maintenance plan continues to rely on federal emission standards for new motor 

vehicles. These requirements include the federal Tier II emission standards for new light and 

medium duty cars and trucks as well as standards for heavy duty on-road and non-road vehicles. 

As noted in Table 2 above, on-road mobile sources are responsible for the highest CO 

concentrations in Grants Pass. That is because cars and trucks moving through an area can 

assemble in significant numbers at areas of heavy traffic. High CO concentrations typically 

occur over a small area close to a congested intersection; CO dissipates quickly over distance 

from a source. 

Emission reductions mandated by the Federal Motor Vehicle Emission Control Program have 

been primarily responsible for the large decrease in ambient CO concentrations in the past. 

Before CO emissions were regulated, a typical car of the 1950s emitted approximately 87 grams 

of CO per mile. Since then, federal rules have lowered CO emissions to the point where today’s 

federal Tier II requirements limit cars to no more than 3.4 grams CO per mile - a 95% reduction 

of CO. This program will continue to be an effective control for on-road mobile source 

emissions in the future. 

Major New Source Review

Under this limited maintenance plan, the emission control requirement for new or expanding 

major industry in Grants Pass area will continue to require Best Available Control Technology 

(BACT). BACT technology provides a high level of control while allowing some flexibility and 

consideration of the cost effectiveness of different control options.

It should be noted that very few new or expanding industrial sources are expected in the Grants 

Pass area, and as shown in Table 2, stationary point sources are only about 1 percent of the CO 

emissions. 

Woodsmoke Curtailment

As noted in the previous section, residential wood combustion emissions make up most of the 

stationary area source emissions, and as shown in Table 2, represent 16 percent of the total 

annual and 25 percent of season CO emissions in Grants Pass. The woodsmoke emission control 

efforts have significantly reduced particulate emissions through emission certification standards 

for new stoves, change-out programs to encourage removal of non-certified stoves, and a local 

voluntary curtailment program to reduce wood burning during stagnant weather periods. These 

efforts will be continued under this limited maintenance plan, and are expected to provide 

modest reductions in CO emissions in Grants Pass. 

Conformity requirements

Federal transportation conformity rules (40 CFR parts 51 and 93) and general conformity rules

(58 FR 63214) continue to apply under a limited maintenance plan. However, as noted in the 

Paisie Memo, these requirements are greatly simplified. An area under a LMP can demonstrate 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 7
conformity without submitting an emissions budget, and as a result emissions do not need be 

capped nor a regional emissions analysis (including modeling) conducted.

4

7. Contingency Plan

Section 175(A) of the Clean Air Act requires a maintenance plan include contingency measures 

necessary to ensure prompt correction of any violation of the standard that may occur. The first 

Grants Pass maintenance plan contained contingency measures that would be implemented based 

on monitoring data – if CO concentrations exceeded 90 percent of the 8-hour standard (8.1 ppm) 

or if a violation of the standard were to occur. Since the Grants Pass CO monitor was removed 

in 2006, these contingency measures are no longer are applicable, other contingency measures

are needed, which reflect an area like Grants Pass that is eligible for the LMP option and at low 

risk of re-violating the CO standard. 

Contingency measures typically have several steps for action depending on the severity of air 

quality conditions. The following apply to this limited maintenance plan:

1. If DEQ’s three-year periodic review of CO emissions shows a significant increase in 

emissions, as described in Section 8 of this plan, DEQ will then reestablish ambient CO 

monitoring in Grants Pass. 

2. If the highest measured 8-hour CO concentration in a given year in Grants Pass exceeds the 

LMP eligibility level of 7.65 ppm (85 percent of the 8-hr standard), DEQ will evaluate the cause 

of the CO increase, and consider forming an advisory committee to recommend strategies.

Within 6 months of the validated 7.65 ppm CO concentration, DEQ will determine a schedule of 

selected strategies to either prevent or correct any violation of the 8-hour CO standard. This will 

allow as choice to be made before or after an actual violation has occurred. 

The contingency strategies that will be considered include, but are not limited to:

• Improvements to parking and traffic circulation

• Aggressive signal retiming program

• Funding for transit

• Implementation of bicycle and pedestrian networks 

DEQ (and the advisory group if needed) may also choose to conduct further evaluation, to 

determine if other strategies are necessary, or to take no further action if the problem was caused 

by an exceptional event. 

3. If a violation of the CO standard occurs, and is validated by DEQ, in addition to step 2 above, 

DEQ will replace the BACT requirement for new and expanding industries listed in Section 6, 

with the Lowest Achievable Emission Rate (LAER) technology, and reinstate the requirement to 

offset any new CO emissions. Additional CO emission reduction measures will be considered as 

4 See Paise Memo in Appendix A for additional information on conformity requirements. 

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 8

 
may be identified in the evaluation in step 2. Committing to further study in this way gives DEQ 

flexibility in choosing an appropriate approach should the need arise.

8. Verification of Continued Attainment

As described in this plan, CO levels in the Grants Pass UGB have steadily declined over the last 

15 years, and are not expected to increase or threaten compliance with the CO standard. Given 

that the Grants Pass CO monitor was removed in 2006, another method of verifying continued 

attainment with the CO standard is needed.

DEQ will calculate CO emissions every three years as part of the Statewide Emission Inventory, 

which is submitted to EPA for inclusion in the NEI. DEQ will review the NEI estimates to 

identify any increases over the 2005 emission levels and source categories shown in Table 2 of 

this plan, and report on them in the annual network plan for the applicable year. Since on-road 

motor vehicles are the predominant source of carbon monoxide in Grants Pass (about 70%), this 

source category will be the primary focus of this review. Any increase in CO emissions will be 

evaluated by DEQ to verify it is not due to a change in emission calculation methodology, an 

exceptional event, or other factor not representative of an actual emissions increase. 

Recognizing there could be a minor, insignificant emissions increase, for the purposes of 

triggering the Contingency Plan described in Section 7, DEQ will consider an increase of 5 

percent in either the total annual or season emissions, or in the on-road mobile source category, 

as representing a “significant” emission increase.

Grants Pass Carbon Monoxide Limited Maintenance Plan Page 9
Appendix A

EPA 1995 Paisie Memo

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix A, Page 1
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix A, Page 2
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix A, Page 3
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix A, Page 4
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix A, Page 5
Appendix B

Grants Pass 2005 Carbon Monoxide Emission Inventory

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 1
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 2
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 3
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 4
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 5
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix B, Page 6
Appendix C

EPA October 16, 2006 Approval Letter for removing the carbon monoxide FRM monitor

Grants Pass

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix C, Page 1
Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix C, Page 2
Appendix D

Inventory Preparation and Quality Assurance Plan

for the

Grants Pass Urban Growth Boundary Limited CO Maintenance Plan

Inventory Preparation and

Quality Assurance Plan

for the

Grants Pass Urban Growth Boundary

Limited Carbon Monoxide Maintenance Plan

March 2014

 Oregon Department of the Environmental Quality

Environmental Solutions Division, Technical Services Section

811 SW Sixth Avenue

Portland, Oregon 97204

Phone 503.229.5359 • Fax 503.229.5675

OREGON DEPARTMENT OF ENVIRONMENTAL 

QUALITY

 

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 1
TABLE OF CONTENTS

TABLE OF CONTENTS......................................................................................... Error! Bookmark not defined.

TABLE OF FIGURES ...........................................................................................................................................3

TABLE OF TABLES .............................................................................................................................................3

1 INTRODUCTION........................................................................................................................................4

1.1 Geographic Area ..............................................................................................................................4

1.2 Temporal Resolution........................................................................................................................5

2 INVENTORY DEVELOPMENT.....................................................................................................................5

2.1 Data Categories................................................................................................................................6

2.2 Emission Sectors ..............................................................................................................................6

3 SPATIAL ALLOCATION METHODS.............................................................................................................7

4 TEMPORAL ALLOCATION METHODS........................................................................................................9

4.1 Permitted Point................................................................................................................................9

4.2 Aircraft and Locomotives.................................................................................................................9

4.3 Nonpoint (area) and Nonroad Vehicles & Equipment.....................................................................9

4.3.1 Open Burning ...............................................................................................................................9

4.3.2 Small Stationary Fossil Fuel Combustion.....................................................................................9

4.3.3 Residential Wood Combustion ....................................................................................................9

4.3.4 Wildfires and Prescribed Burning ................................................................................................9

4.3.5 Structure Fires..............................................................................................................................9

4.3.6 Nonroad Vehicles & Equipment Excluding Aircraft and Locomotives.......................................10

4.4 On-Road Mobile: Vehicle Exhaust .................................................................................................10

5 QUALITY ASSURANCE AND QUALITY CONTROL.....................................................................................10

6 EXTERNAL AUDITS..................................................................................................................................10

7 PERSONNEL ............................................................................................................................................10

8 SCHEDULE ..............................................................................................................................................11

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 2
TABLE OF FIGURES

Figure 1-1. Grants Pass UGB and CO Maintenance Area................................................................................5

TABLE OF TABLES

Table 2.1. 1993 CO Season Day Emissions by Category .................................................................................6

Table 2.2. 1993 CO Season Day Emissions by Source Category .....................................................................7

Table 3.1. Data Sources, Spatial Surrogates and Boundaries.........................................................................8

Table 8.1. Draft Project Schedule: Grants Pass Limited Maintenance Plans for CO ....................................12

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 3
1. INTRODUCTION

Grants Pass was designated a nonattainment area for carbon monoxide (CO) on December 15, 

1985 and classified as moderate upon enactment of the Clean Air Act Amendments in 1990. The 

highest 8-hour carbon monoxide concentration recorded in Grants Pass occurred in 1982 at level 

of 14.4 ppm. In that same year, Grants Pass exceeded the federal 8-hour standard of 9 ppm on 

28 days. The 1-hour standard has never been exceeded in Grants Pass. By the late 1980’s, 

maximum levels were closer to the standard level, and the last exceedances of the standard was 

in 1990. 

The area was reclassified to attainment for the 8-hour CO standard in August 2000 when EPA 

approved the first maintenance plan designed to maintain compliance with the 8-hour CO 

standard through the year 2015. The second maintenance plan is due in 2015. Once approved by 

EPA, the second maintenance plan will fulfill the final maintenance planning requirements of the 

Clean Air Act. This Inventory Preparation Plan is in support of the development of the required 

second CO maintenance plan. 

The maintenance area is the Central Business District in downtown Grants Pass (Figure 1.1).

However, EPA considered the Urban Growth Boundary to be a more representative are of 

influence for CO emissions and the 1993 emission inventory was prepared for UGB. Similar 

approach is recommended for the second maintenance plan. CO monitor was located at 215 SE 

Sixth Street, known as the Wing Building. Measured CO levels were so low that the monitor was 

removed with EPA approval at the end of 2005. Because on-road mobile vehicle emissions are 

the primary source of CO in Grants Pass (over 70%), Oregon DEQ will track any increase in 

emissions as reported every three years through the Statewide Emission Inventory which is 

submitted to EPA for inclusion in the National Emission Inventory (NEI). Significant increase in 

emissions inventory that is not due to a change of emissions factor or computer models will 

prompt DEQ to resume monitoring for CO in Grants Pass. 

The Grants Pass second maintenance plan qualifies for the Limited Maintenance Plan (LMP) 

approach because it satisfies all the requirements outlined in the Limited Maintenance Plant 

Option for Nonclassifiable CO Nonattainment Areas (Paisie memo, 1995). For the 8-hour CO, in 

the most recent two years of data, the maximum value of 4.0 ppm was recorded on November 3, 

2004 and the second maximum value of 3.9 was recorded on March 22, 2005. The risk to the 

community of exceeding the CO standard is low. 

Oregon DEQ proposes using existing information from the EPA 2005 National Emission Inventory 

(NEl) to create the emissions inventory for CO sources in Grants Pass. The exception will be onroad emission estimates, which will be obtained from Sierra Research Inc., working under 

contract for the Rogue Valley Council of Governments (RVCOG). This document describes the 

planned approach to the LMP EI and the basis for selecting that approach.

1.1. Geographic Area

The city of Grants Pass is located in the Rogue Valley, northwest of Medford and along the Rogue 

River. The city is approximately 11 sq. miles in area, and the US Census 2011 population was 

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 4
34,533. The elevation of the city is approximately 277 meters (801 ft). Figure 1-1 shows the 

geographic area of the Grants Pass UGB.

Figure 0-1. Grants Pass UGB and CO Maintenance Area

1.2 Temporal Resolution

The CO season is defined as three consecutive months, December 1st through the end of 

February. As such, season day emissions in addition to annual emissions will be included in the 

inventory. The unit of measure for annual emissions will be tons per year (tpy), and the unit of 

measure for season day emissions will be pounds per day (lb/day).

2. INVENTORY DEVELOPMENT

The DEQ will develop an emission inventory using EPA 2005 National Emissions Inventory (NEI) 

data for Josephine County. We will temporally allocate the EI data to CO season, and spatially 

allocate the county-wide NEI data to the Grants Pass UGB, or to buffers around the UGB, 

depending on emissions category. All data sources and allocation methods will be documented. 

The emission inventory will be consistent with the 1993 inventory.

The exception will be on-road mobile sources; for the 2005 on-road mobile emission inventory, 

emissions will be estimated by Sierra Research as contracted by the Rogue Valley Council of 

Governments (RVCOG) and in coordination with the Oregon Department of Transportation 

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 5
(ODOT). Sierra Research will generate emissions estimates through activity in the form of 2005 

VMT data provided by ODOT in conjunction with emission factors generated by the EPA 

MOVES2010b model. DEQ staff will review the MOVES model inputs for appropriateness. 

2.1 Data Categories

From the base year (1993) emission inventory for the maintenance plan, the most significant 

categories of CO emissions in the Grants Pass UGB are on-road mobile vehicle exhaust, 

residential wood combustion, permitted point sources, and nonroad vehicles and equipment. 

Table 2.1 shows the breakdown by category for worst-case day CO emissions in 1993.

Table 0.1. 1993 CO Season Day Emissions by Category

Emission Inventory Category Emissions per Day 

(lb/day)

Percent of Daily 

Emissions

On-Road Mobile Vehicle Exhaust 48,104 76%

Residential Wood Combustion 10,094 16%

Permitted Point Sources 2,386 4%

Nonroad Vehicles & Equipment 1,684 3%

All other sources 1,285 2%

------- -------

Total 63,553 100%

2.2 Emission Sectors

We propose 14 emission inventory sources be included in this LMP for the Grants Pass 

maintenance area. The sectors are based on a review of emission sectors listed in the 1993 

maintenance plan, and an analysis of 2005 NEI data. Table 2.2 shows the breakdown by source 

category of average daily CO emissions in 1993 inventory; DEQ will use the same source 

categories as in the 1993 inventory.

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 6
Table 0.2. 1993 CO Season Day Emissions by Source Category

Emission Source Category Emissions per Day 

(lb/day)

Percent of WorstCase Day Emissions

Permitted Point Sources 2,386 3.75%

Open Burning 825 1.30%

Small Stationary Fossil Fuel Combustion(a) 258 0.41%

Residential Wood Combustion 10,094 15.88%

Wildfires & Prescribed Burning 64 0.10%

Structure Fires 138 0.22%

Aircraft & Airport Related 0(b) 0%

Locomotives 9 0.01%

Recreational Marine 34 0.05%

Nonroad Vehicles & Equipment 1,641 2.58%

Onroad Mobile: Exhaust 48,104 75.69%

------- --------

Total 63,553 100%

(a) Non-permitted stationary residential, industrial, commercial, and institutional fuel use

(b) Grants Pass Airport located outside the Grants Pass UGB, so emissions are not included. However, DEQ 

staff will verify that no additional airports/heliports are located within the UGB for the 2011 EI.

3. SPATIAL ALLOCATION METHODS

For emissions sources with specific coordinates, emissions will be mapped to either the UGB or 

other boundary, depending on emissions source category. For sources without specific coordinates, 

spatial surrogates will be used to approximate both the location and magnitude of emissions. 

Spatial surrogates are typically used to approximate emissions inside smaller boundaries from larger 

boundaries. For sources without specific coordinates, county-wide emissions will be spatially 

allocated to UGB using the formula:

EUGB = ECOUNTY * SurrogateUGB / SurrogateCOUNTY

Where EUGB = emissions in UGB, 

ECOUNTY = county-wide emissions

SurrogateUGB = surrogate activity in UGB

SurrogateCOUNTY = surrogate activity in county

Data sources, spatial surrogates or boundaries used for each category of emissions are detailed 

in Table 3-1.

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 7
Table 0.3. Data Sources, Spatial Surrogates and Boundaries

Sector and Category EI Data Source Spatial Surrogate Surrogate Data Source Comment

Permitted Point 2005 NEI within 25-mi buffer of the UGB 

(consistent with 1993 EI)

DEQ GIS data Source coordinates used

Nonpoint (Area)

Open Burning 2005 NEI 

and/or DEQ 

records

zoning and burn ban boundary DEQ and Josephine County residential (BBB) and other (zoning)

Small Stationary Fossil Fuel Combustion 2005 NEI zoning Josephine County zoning non-permitted source fuel use

Residential Wood Combustion 2005 NEI Census block group US Census Census data used for allocation

Wildfires and Prescribed Burning 2008 & 2011 

NEI

Average of two year's worth of 

data: fires within a 9.5 km 

buffer around the UGB(a)

2008 & 2011 NEI Fire coordinates used: Average of two year's worth of data 

from the NEI

Structure Fires 2005 NEI population US Census 2005 Census data

Nonroad

Aircraft & Airport related 2005 NEI Grants Pass airport located 

outside UGB

2011 NEI (airport location) DEQ staff will verify via GIS mapping whether or not any 

additional airports/heliports are located within the UGB

Locomotives

Line-Haul (Road) 2005 NEI track miles DEQ GIS Active track miles only

Switching (Yard) 2005 NEI yard location (polygon) DEQ GIS

Marine (recreational) 2005 NEI boat use days by waterbody Oregon State Marine Board 2005 Recreational boat use days from OSMB

2005 NEI zoning Josephine County zoning EPA Nonroad Model categories

Onroad Mobile

Exhaust RVCOG road miles MOVES runs specific to UGB MOVES runs w/ODOT TDM VMT (RVCOG/Sierra Research)

(a) Fire spatial and temporal data has become increasingly sophisticated since the 1993 EI. The date, emissions, and coordinates of specific fires

are now available in the 2008 and 2011 NEIs. As such, a 9.5-km buffer around the UGB was chosen, approximating the fire boundary in the 2008 

Klamath Falls PM2.5 Attainment Plan.

Nonroad Vehicles & Equipment

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 8
4. TEMPORAL ALLOCATION METHODS

Annual emissions will be adjusted from tons per year to lbs per season day for each source 

category. Methods for each category are described below, and all methods are consistent with 

the 1993 EI. 

4.1 Permitted Point

Typical day emissions estimates will be calculated from annual emissions utilizing facility 

operating schedules taken from source permits. Seasonal adjustment may also be estimated 

from source annual reports, and DEQ point source emissions estimation reports.

4.2 Aircraft and Locomotives

Aircraft and locomotive activity will be considered uniform throughout the year. Annual 

emissions will be divided by 365 days to estimate season day emissions.

4.3 Nonpoint (area) and Nonroad Vehicles & Equipment

For nonpoint (area) and nonroad vehicles and equipment (excluding aircraft and locomotive), 

temporal allocation to season will follow the formula:

Annual to Typical Season Day = (Annual Emissions * SAF) / (weekly activity * 52 weeks/yr)

Where SAF = Seasonal Adjustment Factor =

 = (Season Activity * 12 months) / (Annual Activity * Season Months)

(Reference: EPA-450/4-91-016, p. 5-22)

4.3.1 Open Burning

Open burning will be temporally allocated using SAF values and activity in days per week; using 

2005 permit and complaint data, DEQ may either verify the SAF values used in the 1993 EI or 

develop new SAF values based on the 2005 data. Regardless, the method will be consistent with 

the 1993 EI.

4.3.2 Small Stationary Fossil Fuel Combustion

Annual emissions from small stationary fossil fuel combustion will be temporally allocated using 

SAF values and activity in days per week taken from the 1993 EI. SAF values for these sources in 

the 1993 EI were taken directly from EPA-450/4-91-016, Table 5.8-1, p. 5-18.

4.3.3 Residential Wood Combustion

Annual emissions from residential wood combustion will be temporally allocated using SAF 

values and activity in days per week taken from the 1993 EI. SAF values for these sources in the 

1993 EI were taken directly from EPA-450/4-91-016, Table 5.8-1, p. 5-18.

4.3.4 Wildfires and Prescribed Burning

As wildfires and prescribed burning are date-specific events, DEQ will temporally allocate 

emissions from these sources using fire date data, available from the EPA National Emission 

Inventory (NEI). SAF values will be calculated using annual and seasonal fire dates.

4.3.5 Structure Fires

As structure fires are date-specific events, DEQ will temporally allocate emissions from these 

sources using fire date data. Fire data used by DEQ to estimate structure fire emissions for the 

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 9
NEI is supplied by the state fire marshal. A seasonal adjustment factor (SAF) will be estimated 

using annual and seasonal fire dates.

4.3.6 Nonroad Vehicles & Equipment Excluding Aircraft and Locomotives

Sources of emissions covered by the Nonroad model include the following categories:

• Recreational marine • Railway maintenance

• Agricultural • Lawn & garden

• Construction • Industrial

• Light commercial • Logging

• Airport Ground Support Equipment (GSE)

Emissions from these categories will be temporally allocated to season using SAFs and weekly 

activity taken from the 1993 emission inventory.

4.4 On-Road Mobile: Vehicle Exhaust

ODOT will develop on-road temporal allocation profiles (monthly and hourly) from available traffic 

count station volumes within UGB/Josephine County. The ultimate source of the profiles may be seasonal 

adjustment calculations performed by DEQ staff for the 1993 EI; however ODOT has the discretion of 

making changes or revisions to the factors.

5. QUALITY ASSURANCE AND QUALITY CONTROL

DEQ will be using existing data that has already been quality checked. DEQ staff will perform 

quality assurance for accuracy, completeness, and representativeness on the spatial and 

temporal allocation of emissions from the existing inventory. DEQ staff will review MOVES (onroad EF model) inputs for appropriateness.

6. EXTERNAL AUDITS

DEQ is willing to be audited by the EPA, and make changes to this inventory preparation and 

quality assurance plan if warranted.

7. PERSONNEL

DEQ personnel responsible for the Grants Pass CO Limited Maintenance Plan inventory include:

Wendy Wiles, DEQ Environmental Solutions Division Administrator

Jeffrey Stocum, Air Quality Technical Services Section Manager

Emission Inventory and Air Quality Information Systems

Christopher Swab, Senior Emission Inventory Analyst

Brandy Albertson, Emission Inventory Analyst

Wesley Risher, Emission Inventory Analyst

Miyoung Park, Emission Inventory Specialist

Quality Assurance

Anthony Barnack, Air Monitoring Coordinator

David Collier, Air Quality Planning & Development Manager

Aida Biberic, Air Quality Planner

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 10
8. SCHEDULE

Table 8.1 shows the draft schedule for document submittal to EPA Region 10 and other tasks to 

be completed. DEQ will submit a draft inventory to EPA upon their request, and will submit a 

final inventory to EPA according to this Inventory Preparation and Quality Assurance Plan.

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 11
Table 0.4. Draft Project Schedule: Grants Pass Limited Maintenance Plans for CO

Define Scope

SIP Development Plan

SIP Development Phase

Rulemaking Phase

EQC Adoption

Submit the final SIP to EPA

30-Dec-1313-Jan-1427-Jan-1410-Feb-1424-Feb-1410-Mar-1424-Mar-147-Apr-1421-Apr-145-May-1419-May-142-Jun-1416-Jun-1430-Jun-1414-Jul-1428-Jul-1411-Aug-1425-Aug-148-Sep-1422-Sep-146-Oct-1420-Oct-143-Nov-1417-Nov-141-Dec-1415-Dec-1429-Dec-1412-Jan-1526-Jan-159-Feb-15

Define Scope

SIP Development Plan

Approve work on this SIP

Fast Track Checklist

SIP Developmnet Plan

IPP

Timeline

Submitt SIP Dev. Plant to EPA and GP MPO

SIP Development Phase

Emissions Inventory Development

Drafting the Plan

Review Draft SIP

Rulemaking Phase

Draft the SIP, Fact Sheet, Notice

Review Final SIP, Fact Sheet, Notice

Draft plan submitted to EPA, DOJ, Andrea

Rulemaking documents due to DA for approval

Public Involvement

Finalize the SIP

Review the SIP

Finalized staff report due to directors office

EQC adoption

Submit the final SIP to EPA

Draft Project Schedule: Grants Pass Limited Maitenance Plans for CO

Grants Pass Carbon Monoxide Limited Maintenance Plan Appendix D, Page 12