## State of California

Staff Report



# Yuba City

- Marysville PM2.5 Maintenance

Plan and Redesignation Request

Release Date:

Schedule d for Consideration: April 25 , 2013 California Environmental Protection Agency 

# AIR R ESOURCES BOARDThis document has been reviewed by the staff of the Californ ia Air Resources Board

and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Air Resources Board, nor does the mention of trade names or commercial products constitute endorsement or re commendation for use.TABLE OF CONTENTS

I. BACKGROUND

................................ ................................ ................................ ...... 1

II. REDESIGNATION REQUIREMENTS

................................ ................................ .... 2

III. EVALUATION OF THE REDESIGNATION REQUEST/MAINTENANCE PLAN

... 2

A. Monitoring Shows Compliance with PM2.5 Standard

................................ ........ 3

B. Applicable Act Requirements are Satisfied

................................ ....................... 4

C. Attainment Results from Permanent and Enforceable Emission Reductions

.... 4

D. Maintenance Plan Provides for Continuing Attainment

................................ ..... 4

1. Attainment Year Emission Inventory

................................ ............................ 4

2. Maintenance Demonstra tion

................................ ................................ ........ 6

3. Motor Vehicle Emission Budgets

................................ ................................ . 8

4. PM2.5 Monitoring Network

................................ ................................ .......... 8

5. Verification of Continued Attainment

................................ ........................... 8

6. Contingency Plan

................................ ................................ ........................ 8

IV. STAFF RECOMMENDATION

................................ ................................ ................ 91

I. BACKG R OUND

The Yuba City

- Marysville a rea in the Feather River Air Quality Management District (District) was designated as nonattainment for the 2006 24

- h ou r fine particulate (PM2.5) National Ambient Air Quality Standard ( standard ) on December 1 4

, 2009

. The

nonattainment area includes Sutter County and a portion of Yuba County and was designated nonattainment based on 2005 to 2007 Federal Reference Monitor (FRM)

data. Figure 1 outlines the nonattainment area and shows the location of the monito ring

site. The Yuba City

- Marysville nonattainment area has a single PM2.5 FRM monitor,

which in 2007 had a design value of 40 ug/m3. Beginning in 2008, the 24

- hour design

value has been below the standard.

Figure 1. Map of the Yuba City

- Marysville PM2. 5 Nonattainment Area2

II. REDESIGNATION REQUIREMENTS

On June 8, 2010 , ARB submitted a request to the U.S. E nvironmental Protection Agency (U.S. EPA) to find the Yuba City

- Marysville nonattainment area in attainment of

the 35 ug/m3 24

- hour PM2.5 standar d. The U.S. EPA took final action on January 10, 2013 determining that the area attained the standard. This clean data finding

, under the U.S. EPA Clean Data Policy for the Fine Particulate National Ambient Air Quality Standards (Clean Data Policy), sus pends the majority of the planning

elements under the Clean Air Act ( Act )

.

Air Resources Board ( ARB ) staff review ed the District’s Yuba City

- Marysville PM2.5 Nonattainment Area Redesignation Request and Maintenance Plan (Redesignation Request/Maintenanc e Plan) within the context of the Act , which identifies the following requirements an area must meet t o be redesignated to attainment:

A. The area has attained the standard ; B. The applicable implementation plan is fully approved under Act section 110 (k)

, and the area has met all applicable requirements of Act section 110 and part D ; C. T he PM2.5 air quality improvements are due to permanent and enforceable

emission reductions ; and

D. The area has a fully approved maintenance plan satisfying section 175A of the

Act

.

The Act also sets the general framework for maintenance plans 1 . Each PM 2.5

m aintena nce p lan must provide for continued maintenance of the PM 2.5 standard for

ten years after redesignation and include the following components :

1. Attainment emission invento ry;
2. Maintenance demonstration ; 3. Commitment to continue the monitoring network operation;

4. Commitment for verification of continued attainment; and

5. Contingency plan to promptly correct any violation of the P M 2.5 standard that

occurs after the area has been r edesignated.

III. EVALUATION OF THE REDESIGNATION REQUEST/MAINTENANCE PLAN

Based on review of the District Redesignation Request/Maintenance Plan and

su pporting technical analysis

, ARB staff concurs that the Redesignation Request/Maintenance Plan meets the Act ’s requirements

. The following sections describe the major elements of the Redesignation Request/Maintenance Plan

.

1 Calcagni, John, Memo randum, Procedures for Processing Requests to Redesignate Areas to Attainment, Office of Air Quality Planning and Standards , Research Triangle Park, North Carolina, September 4, 1992. http://www.epa.gov/ttn/oarpg/t5/memoranda/redesignmem090492.pdf3

A. Monitoring Shows Compliance with PM2.5 Standard

As shown in Figure 2 , PM2.5 air quality has improved significantly over the last few

years in the Yuba City

- Marysville nonattainment a rea. PM 2.5 is measured at a single monitoring station, Yuba City

- Almond Street (Figure 1 ) , where an FRM sampler collects

24

- hour average samples daily

. The area first reached compliance with the 24

- hour

standar d in 2008, with a design value of 33 ug/m3. The design value represents the

3

- year average of the 98 th percentile of 24

- hour PM2.5 concentrations. Although wildfires that occurred in the summer of 2008 resulted in a number of

exceedances of the 24

- hour standard, U.S. EPA’s exceptional events rule allows for

exclusion of exceedances due to natural events. Since then, the area has continued to measure compliance with the 24

- hour standard

. Figure 2 shows the design values at

the Yuba City site between 200 1 and 20 1 2 , demonstrating attainment

.

Between 2001 and 201 2 , annual average and 24

- hour PM2.5 design values in the Yuba City

- Marysville nonattainment area decreased by nearly 50 percent due to ongoing

emission reductions. The downward trend was not a r esult of “unusually favorable meteorology”. Between 2008 and 2012, the area experienced a variety of meteorological conditions, including 2011 which was extremely conducive to high PM2.5 pollution including stagnation that persisted over 20 days . Despite this, 2011 and 2012 design values are significantly below the 24

- hour standard.

Figure 2 . 24

- hour Design Values at Yuba City*

* 2008 wildfire impacts excluded from the design value calculation4

B. Applicable Act Requirements are Satisfied

ARB and th e District have met all of the Act requirements applicable for a PM 2.5 nonattainment area to be considered for redesignation. On June 8, 2010, ARB requested a “clean data” finding for the 24

- hour PM2.5 standard for this area

. On January 10, 2013 , U.S. EP A signed a final rule determining that the Yuba City

- Marysville nonattainment area has attained the 24

- hour PM2.5 standard based on

2009

- 2011 data

. This clean data finding suspended the obligation to submit State Implementation Plan ( SIP ) elements that pr ovide for attainment of the standard

, implementation of all reasonably available control measures, reasonable further

progress (RFP) , and implementation of contingency measures for failure to meet

deadlines for RFP and attainment. The only SIP element rem aining is an emission inventory. To address the remaining SIP requirement, the District Redesignation Request/Maintenance Plan includes a 2011 winter emission inventory

.

C. Attainment Results from Permanent and Enforceable Emission Reductions

Numerous Dis trict and State emission control programs have been adopted and implemented over the last several years, providing permanent and enforceable reductions in direct PM2.5 and PM2.5 precursor emissions. Many of these programs will provide additional emission reductions during the maintenance period, ensuring continued compliance with the standard. The Redesignation Request/Maintenance

Plan lists post

- 2006 control measures that are responsible for the significant improvements in PM2.5 air quality , including re strictions on open burning and residential fuel combustion, and on

- road and off

- road motor vehicle and equipment control

programs.

D. Maintenance Plan Provides for Continuing Attainment

S ection 175 A of the Act establishes the required elements of a mainte nance plan for areas seeking redesignation from nonattainment to attainment. Using an attainment year inventory and future inventory projections, p lans must demonstrate continued attainment through the first 10

- year maintenance period. Comprehensive inve ntories were developed for the representative attainment year (2011), an interim year (2017), and the end of the maintenance period (2024) for directly emitted PM2.5 and PM2.5

precursors

.

1. Attainment Year Emission Inventory

An emission inventory is a cri tical tool used to support evaluation , contro l, and mitigation of air pollution which is comprised of a systematic listing of the sources of air pollutants along with the amount of pollutants emitted from each source or category over a given period of time . Emission inventories are estimates of the air pollutant emissions

released into the environment

– they are not direct ambient concentration5

measurements. As part of the maintenance plan, the District submitted an attainment year inventory characterizin g emissions in the maintenance area. U.S. EPA recommends that the attainment year inventory be from one of the three years used to demonstrate attainment. In case of the Yuba City

- Marysville

nonattainment area , 2011 was selected as an attainment year in ventory coinciding with the last year in the U.S. EPA clean data finding

. The attainment year inventory includes emissions of PM2.5, volatile organic compounds (VOCs), oxides of nitrogen (NOx), oxides of sulfur (SOx), and ammonia (NH3).

An e mission inv entory should be consistent with the nature of the air quality problem.

Since the 2006 24

- hour PM2.5 standard was designated to protect against peak exposures, the inventory should reflect the season when most exceedances occur. As

demonstrated in the Re designation Request/Maintenance Plan and also shown in Figure 3 , all of the highest PM2.5 concentrations in the Yuba City

- Marysville

nonattainment a rea over the course of the year occur during the winter. Therefore, the winter inventory developed for the attainment year and future years is the most appropriate for SIP planning purposes. Table 1 lists 2011 winter emission inventories split by source category

.

Figure 3. Total Count of Exceedance Days per Month Based on 11 Years of Data

* Excluding data affected by exceptional events.

Table 1 . Attainment Year Winter Emission Inventory (tons/day)

Category VOC NOX SOX PM2.5 NH3

STATIONARY 4.0 4.4 0.1 0.9 0.4

AREAWIDE 5.5 1.1 0.1 3.8 4.5

ON

- ROAD MOTOR VEHICLES 2.8 8.4 0.0 0.3 0.2

OTHER MOBILE SOURCES 2.3 5.4 0.1 0.3 0.0

TOTAL 14.6 19.3 0.4 5.3 5.06 2. Maintenance Demonstration

In order to demonstrate maintenance of the PM2.5 24

- h ou r standard through the year 2024, the District compiled a n emission inventory for an attainment year (2011) and

formulate d projections for the intermediate year (2017) and for the final year of the maintenance period (2024). The attainment year and projected inventories represent winter emissions which reflect the nature of the PM2.5 problem in the area. If each of the pro jected emission levels is less than the emissions for the attainment year, maintenance of the standard is demonstrated. This approach assumes that ambient concentrations will remain below the standard as long as future emissions are kept

below the attainm ent year emissions. The interim and future year inventories include banked Emission Reduction Credits (ERCs) to demonstrate that the addition of ERC’s will not compromise attainment.

The maintenance demonstration includes emissions of direct PM2.5, SOx , and NOx. The U.S. EPA PM2.5 implementation rule specifies that a precursor is considered “significant” for control strategy development purposes when a significant reduction in the emission of that precursor pollutant leads to a significant decrease in PM2.5 concentration. Such pollutants are known as “PM2.5 attainment plan precursors” (72 FR 20586). The PM2.5 implementation rule also established a presumption that PM2.5, NOx, and SOx are attainment plan precursors, while VOCs and ammonia are

no t unless they are needed for attainment demonstration or are significant for maintaining the NAAQS

.

Although speciation data is not routinely collected, limited data provided by the

U.S. EPA as part of the designation process indicates that carbonaceous aerosols and nitrate are main contributors to high PM2.5 values. Carbonaceous aerosols are the largest component, contributing about 54 percent of the mass, followed by nitrate, which is responsible for about 38 percent of the mass. Although these data are based on

2004

- 2006 samples, the data collected at other northern and central California sites

indicate that while the number of high days has decreased, the high day composition

remains similar from year to year due to the nature of th e PM2.5 problem

.

H igh PM2.5 values occur exclusively under stagnant winter conditions leading to accumulation of primary pollutants and formation of secondar y components . While carbonaceous aerosols are primarily directly emitted into the air, nitrates are secondary

po llutants formed in the atmosphere from gaseous NOx emissions and ammonia. ARB’s programs aimed at reducing NOx emissions have played an important role in reducing the nitrate fraction of PM2.5. Long term nitrate and NOx data collected throughout the Stat e demonstrate that reductions in ambient NOx concentrations have

resulted in commensurate reductions in PM2.5 nitrate concentrations. Past modeling and monitoring studies in northern and central California highlight that reductions in VOCs are not importa nt for reducing either carbonaceous aerosols or nitrate; therefore

, they would not provide any benefit in reducing PM2.5 concentrations. Based on the nature of the PM2.5 problem and an understanding of precursor effectiveness, as well7

as the fact that the area has already attained the standard, VOCs and ammonia are

therefore not significant PM2.5 precursors.

The consolidated emission projections for the Yuba City

- Marysville nonattainment area are presented in Table 2

. Between 2011 and 2024, e missions o f NOx are projected to

decline 37 perce nt while emissions of SOx and direct PM2.5 are projected to increase by a small amount

. The plan demonstrates maintenance of the 24

- h ou r PM2.5 standard because the potential increase in directly emitted PM2.5 and SOx emissions will be fully offset by a greater decrease in nitrate concentrations, as illustrated in Figure 5. Additionally, the level of 2011 emissions corresponds to a design value of

27 ug/m3, which is 24 percent below the standard . This provides additi onal assurance that 2017 and 2024 design values will remain below the standard

.

Table 2 . Projected Changes in Emissions between 2011 and 2024 (tons/day)

Year 2011 2017 2024 2024

- 2011

PM2.5 5.3 5.5 5.4 0.2

NOx 19.3 15.3 11.6

- 7.7

SOx 0.4 0.6 0.6 0.2

ERC's included in the Above Future Year Inventories

PM2.5 1.3 1.3

NOx 0.9 0.9

SOx 0.2 0.2

Figure 5. Comparison of Measured 2011 and Projected 2024 Design Value8 3. Motor Vehicle Emission Budgets

The Redesignation Request/Maintenance Pla n establishes PM2.5 and NOx transportation conformity budgets for 2017 and 2024 to ensure that future emissions

from on

- road mobile sources provide for continuing attainment of the PM2.5 24

- h our standard (Table 3 )

. The District determined that mobile sour ce emissions of VOCs, ammonia, SOx, re

- entrained road dust

, and highway and transit construction dust are not significant for maintaining the standard and do not need motor vehicle emission budgets.

Table 3 . Motor Vehicle Emission Budgets (tons/day)

Year NOx PM2.5

Adjusted
Budgets Safety

Margin Total

Budgets Total

Budgets

2017 4.6 0.7 5.3 0.2

2024 2.6 0.5 3.1 0.2

4. PM 2.5 Monitoring Network

The existing PM 2.5 monitoring network in the Yuba City

- Marysville nonattainment area

includes a PM2.5 FRM monit or located at 773 Almond Street in Yuba City operating on a daily schedule

, and a non

- Federal Equivalence Method ( non

- FEM) Beta Attenuation Monitor (BAM) running in parallel to the FRM

. Together, these two monitors provide the necessary data to demonstrat e continuous compliance with the standard as well as
support Air Quality Index reporting, forecasting air quality episodes, and making burn

decisions in the agricultural burning program

.

5. Verification of Continued Attainment

The ARB is responsible for monitoring PM2.5 air quality within the Yuba City

- Marysville nonattainment area. The ARB also oversees the quality assurance of PM2.5 data and submits annual monitoring network plans to U.S. EPA on behalf of the District. The ARB commits to maintaining a n appropriate PM2.5 monitoring network through the maintenance period, with any potential changes to be developed in collaboration with

U .S. EPA and subject to stakeholder review. To verify continued attainment of the

PM 2.5 standard, the ARB will continue to conduct PM2.5 monitoring and expeditiously

review data as it becomes availabl e to evaluate any risk of impending violations. This will be used as potential trigger for early action in the contingency plan.

6. Contingency Plan

The Act requires the maint enance plan to include contingency provisions for prompt correction of any PM 2.5 standard violation that might occur after the area has be en redesignated to attainment. The maintenance plan is not required to contain fully adopted contingency measures tha t will go into effect without further state action as is9

required in attainment SIPs. Instead, for maintenance plans, the area must have a plan to ensure that contingency measures are adopted once they are triggered.

The District will use the 24

- hour de sign value as the contingency plan trigger . In the

event that the 24

- hour design value exceeds the standard, within 60 days the District will commence analysis, including meteorological evaluation of high PM2.5 days and emission inventory assessment. The District will also analyze the PM2.5 and meteorological data to rule out exceptional event s or instrument malfunction. If a design value triggers the contingency plan, the District will complete sufficient analyses

, by November 1 of the following year

, t o begin adoption of necessary rules for ensuring

attainment and maintenance of the 24

- hour standard

. If new rules are necessary, they would be adopted by August 31 of the year following the completed analysis

. ARB staff believes the contingency requireme nts in the Redesignation Request/Maintenance Plan are adequate to protect air quality in the area.

I V. STAFF RECOMMENDATION

ARB st aff has reviewed the Redesignation Request / Maintenance Plan for the Yuba City

- Marysville nonattainment area and consulted w ith District staff during this review.

ARB s taff finds that the Redesignation Request/Maintenance Plan meet s all applicable

Act requirements

. The monitoring data shows that the area has attained the 24

- hour PM2.5 standard, and the maintenance demonstrati on shows that the standard will be maintained for ten years.

Therefore, staff recommend s that the Board adopt the Yuba City

- Marysville PM2.5 Nonattainment Area Redesignation Request and Maintenance Plan as a revision to the

Calif ornia SIP for submittal to U.S. EPA. In addition, ARB staff recommends that the

Board approve th e District’s request that the Yuba City

- Marysville nonattainment area

be redesi g n ated from nonattainment to attainment for the federal 24

- hour PM 2.5

standard.