**Commonwealth of Pennsylvania**

**Department of Environmental Protection**

######### 

###### Request for Redesignation 

###### As Attainment 

**[Tioga County\
Eight-Hour Ozone Nonattainment Area]{.smallcaps}**

####### September 2006

Bureau of Air Quality

Pennsylvania Department of Environmental Protection

P.O. Box 8468

Harrisburg, PA 17105-8468

717-787-9495

**www.depweb.state.pa.us**

Blank page inserted for copying purposes

TABLE OF CONTENTS

Introduction 1

Section 1 Demonstration of Attainment and Air Quality Trends Analysis

A. Design Value Determination 3

B. Air Quality Trends Analysis 4

C. Climate Trends Analysis 7

D. Additional Trends 11

E. Ozone Transport 13

F. Modeling Analysis 15

Section 2 SIP Approvals and Applicable Requirements

A. Regulatory Requirements 16

B. Nonregulatory Requirements 17

Section 3 Demonstration of Permanent and Enforceable Improvement

A. Base Year (2002) Emission Inventory 19

B. Attainment Year (2004) Emission Inventory 20

C. Control Measures 21

Section 4 Maintenance Plan 24

Acronyms and

Abbreviations 25

TABLES, CHARTS AND FIGURES

TABLE

1-1 Eight-Hour Ozone Statistics 5

1-2 Trajectory Start Points 14

3-1 VOC and NOx Emissions Summary: 2002 and 2004 20

3-2 Highway Vehicles: VMT and Emissions 22

CHARTS

1-1 Eight-Hour Ozone Design Values 5

1-2 Exceedance Day Count 6

1-3 Fourth High Eight-Hour Ozone Values 7

1-4 Relationship between Ozone Exceedances, Solar Insolation and
Temperature 8

1-5 Average Temperatures at the Canton COOP Station 9

1-6 Number of 90 degree days at the Canton COOP Station 10

1-7 Precipitation Totals at the Canton COOP Station 11

1-8 Tioga Population and Labor Force 12

1-9 Pennsylvania Economic Activity Index 13

FIGURE

1-1 HYSPLIT Back Trajectory Analysis 15

INTRODUCTION

Maintaining concentrations of ground-level ozone below the health-based
standard is important because ozone is a serious human health threat,
and also can cause damage to important food crops, forests, and
wildlife.

Repeated exposure to ozone pollution may cause a variety of adverse
health effects for both healthy people and those with existing
conditions including difficulty in breathing, chest pains, coughing,
nausea, throat irritation, and congestion. It can worsen bronchitis,
heart disease, emphysema, and asthma, and reduce lung capacity. Asthma
is a significant and growing threat to children and adults. Ozone can
aggravate asthma, causing more asthma attacks, increased use of
medication, more medical treatment and more frequent visits to hospital
emergency clinics. Because ozone pollution usually forms in hot weather,
anyone who spends time outdoors in the summer may be affected,
particularly children, the elderly, outdoor workers and people
exercising. Children are most at risk from exposure to ozone because
they are active outside, playing and exercising, during the summertime
when ozone levels are highest.

Ozone is one of the most pervasive and detrimental pollutants known to
affect vegetation, causing more injury to trees and crops than any other
air pollutant in the United States. Ozone interferes with
photosynthesis, the process by which plants convert water and sunlight
to food. Ozone makes plants more susceptible to disease, insects, other
pollutants, and harsh weather. It damages the foliage of trees and other
plants, ruining the landscape of cities, parks and forests, and
recreation areas. Research has shown that current ozone concentrations
result in reductions in wood growth in forests of the Northeast of over
10 percent. There is strong scientific evidence showing that current
levels of ozone are reducing crop yields, particularly in sensitive
species - soybean, cotton, and peanuts. Annual crop loss from ozone for
soybeans alone in Illinois, Indiana and Ohio has been calculated to fall
between \$199 million and \$345 million. The U.S. Environmental
Protection Agency (EPA) has estimated national crop yield losses due to
ozone in excess of \$1 billion annually. A key component of ozone,
oxides of nitrogen (NO~x~), contributes to fish kills and algae blooms
in sensitive waterways, such as the Chesapeake Bay.

Ozone is not emitted directly to the atmosphere, but is formed by
photochemical reactions between volatile organic compounds (VOCs) and
NO~x~ in the presence of sunlight. The long, hot, humid days of summer
are particularly conducive to ozone formation, so ozone levels are of
concern primarily during the months of May through September. The
primary sources of man-made VOCs and NO~x~, the ozone precursors, are
the evaporation of fuels and solvents (gasoline and consumer products),
combustion of fuels (motor vehicles, power plants and non-road engines),
and industrial processes.

The EPA has established the maximum limit for ozone pollution allowed in
the ambient air. EPA's National Ambient Air Quality Standard (NAAQS) for
ozone is 0.08 parts per million (ppm) averaged over eight hours.

In 2004, EPA designated Tioga County as nonattainment for the eight-hour
ozone NAAQS based on data from 2001-2003. The subsequent analyses
clearly demonstrate that the ambient air quality in the Tioga County
nonattainment area now meets the eight-hour ozone NAAQS and that the
emission reductions responsible for the air quality improvement are both
permanent and enforceable. This analysis and the maintenance plan
submitted concurrently demonstrates that the Tioga County nonattainment
area has completed all criteria set forth in Section 107(d)(3)(E) of the
Clean Air Act (CAA) and should be officially redesignated as attainment.

Section 107(d)(3)(E) of the CAA states that an area can be redesignated
to attainment if the following conditions are met:

-   The NAAQS has been attained; (Section 1)

-   The applicable implementation plan has been fully approved under
    Section 110(k) of the CAA and the state has met all applicable
    requirements for the area under Section 110 and Part D; (Section 2)

-   The improvement in air quality is due to permanent and enforceable
    reductions in emissions; and (Section 1 and Section 3)

-   A maintenance plan with contingency measures has been fully approved
    under Section 175A. (Section 4)

This redesignation request describes how the Tioga County ozone
nonattainment area satisfies each of the Clean Air Act's Section
107(d)(3)(E) criteria for redesignation to attainment.

Requirements for a public comment process are set forth in Section
110(a)(2) of the CAA and 40 CFR Section 51.102(d). The Department held a
public hearing to receive comments on the proposals on Tuesday,
September 5, 2006, at 1 p.m. at the Wellsboro Borough Building, 28
Crafton Street, Wellsboro, PA. The comment period closed on September
11, 2006. No testimony was presented and no written comments were
received.

**SECTION 1**

**DEMONSTRATION OF ATTAINMENT**

**AND AIR QUALITY TRENDS ANALYSIS**

On April 30, 2004, the EPA promulgated its final nonattainment
designations for the eight-hour ozone NAAQS. (69 *Fed. Reg*. 23858).
Seventeen areas in Pennsylvania were designated as eight-hour ozone
nonattainment areas. These designated nonattainment areas cover 37
counties in Pennsylvania. The eight-hour ozone designations became
effective on June 15, 2004.

Tioga County was classified as a "basic" nonattainment area based on
one-hour and eight-hour ozone concentrations. EPA designations were
based on air-quality monitoring data for 2001, 2002 and 2003. Air
quality in the Tioga County nonattainment area has improved since the
EPA's original designations. Tioga County's 2005 design value (based on
data from 2003, 2004 and 2005) is 81 parts per billion (ppb). Following
EPA criteria a design value below 85 ppb is considered to be attainment.
The Tioga County design value of 81 ppb thus is below the 85 ppb
threshold for nonattainment of the eight-hour ozone standard.
Concentrations are expected to remain below 85 ppb over the next decade.

## **A. DESIGN VALUE DETERMINATION**

Our air-quality analysis is based on ozone data measured at site number
42-117-4000 in Tioga County. The ambient air-quality data analysis for
ozone was completed using the appropriate regulations and guidance
documents. Monitoring procedures were determined in accordance with 40
CFR, Part 58 (40 CFR 1992a). Eight-hour ozone design values were
calculated in accordance with EPA's [Guideline on Data Handling
Conventions for the Eight-Hour Ozone NAAQS]{.underline} (1998).

Tioga County's eight-hour ozone design values have decreased over the
2002 to 2005 time frame. Over the last several years ozone
concentrations at the Tioga County monitor have decreased significantly.

A recent analysis by the EPA (2005) suggests that there have been
substantial ozone reductions due to various emission control programs,
including the NO~x~ SIP Call. EPA's analysis indicates slight reductions
in ozone concentrations prior to the implementation of the NO~x~ SIP
Call (2002 through 2004); an approximately 4% decline between 1997 and
2002, after adjusting for meteorology. More substantial reductions
appear to have occurred after the NOx SIP Call was implemented; an
approximately 10% decline between 2002 and 2004, after adjusting for
meteorology. Ozone concentration reductions in Tioga County appear to be
similar to what the EPA has observed in its analysis. Caution should be
used in this comparison because the department did not adjust Tioga
County's ozone concentrations for meteorological factors.

## **B. AIR QUALITY TRENDS ANALYSIS**

1\. Design Values

The Tioga County ozone monitor began operations during the 1999 ozone
season. It is the only monitor located in the Tioga County nonattainment
area. The monitor has been operated continuously since its installation
date. Trends in ozone design values were analyzed from 2000 through
2005. These were all of the years that the monitor met EPA's
completeness requirements. The year of first operation, 1999, had less
than 90% valid data over the entire ozone season (Apr 1 through Oct 31).

Table 1-1 lists Tioga County's eight-hour ozone design values from
2002 - 2005. These are presented in graphic form in Chart 1-1. Design
values have generally fallen slightly over this time period (3.5%
overall). The Tioga County monitor has exceeded the eight-hour standard
roughly half of the time it has had valid data. The years the monitor
exceeded the standard were due to one year (2002) of unusually high
ozone concentrations.

2\. Exceedances

Exceedance trends were examined over the 2000-2005 time period. An
exceedance is defined as any day the Tioga County monitor recorded a
valid eight-hour ozone concentration greater than 84 ppb. The time
period examined met the 90% valid days requirement outlined in the EPA
guideline. Exceedance days for Tioga County are listed in Table 1-1 and
graphed in Chart 1-2.

Exceedance days have generally declined over the 2000-2005 time period.
The Tioga County monitor averages 3.2 exceedance days per ozone season.
This average was taken for ozone seasons with at least 90% valid data
over the entire season. Half of the monitor exceedances at the Tioga
County monitor occurred during the 2002 ozone season. If data from
2003-2005 this year is removed from consideration, Tioga County's
average exceedance rate drops to 1.6 exceedances per ozone season.

Table 1-1

Tioga County

Eight-Hour Ozone Statistics

+------+-------------+-----------------+-------------+---------------+
| Year | \% Valid    | Design Value    | 4^th^ High  | Exceedance    |
|      | Days        |                 |             | days          |
|      |             | (PPM)           | (ppm)       |               |
+------+-------------+-----------------+-------------+---------------+
| 1999 | 65.9%       |                 | 0.082       | 2             |
+------+-------------+-----------------+-------------+---------------+
| 2000 | 100.0%      |                 | 0.078       | 2             |
+------+-------------+-----------------+-------------+---------------+
| 2001 | 99.1%       |                 | 0.083       | 3             |
+------+-------------+-----------------+-------------+---------------+
| 2002 | 99.5%       | 0.084           | 0.093       | 8             |
+------+-------------+-----------------+-------------+---------------+
| 2003 | 91.6%       | 0.086           | 0.084       | 3             |
+------+-------------+-----------------+-------------+---------------+
| 2004 | 94.9%       | 0.085           | 0.079       | 0             |
+------+-------------+-----------------+-------------+---------------+
| 2005 | 97.2%       | 0.081           | 0.080       | 0             |
+------+-------------+-----------------+-------------+---------------+

Chart 1-1

**Eight-Hour Ozone Design Values**

![](media/image3.wmf){width="6.250694444444444in" height="3.75in"}

**Chart 1-2**

**Exceedance Day Count for the Tioga County Nonattainment Area**

![](media/image4.wmf){width="6.240277777777778in"
height="3.7395833333333335in"}

3\. 4th High Eight-Hour Ozone Trends

Eight-hour ozone design values are based on the 4^th^ highest
concentrations at a particular monitor over a three-year time period. An
analysis of yearly "4^th^ highs" yields an understanding of why design
values change over time. Again, only years containing more than 90%
valid days (2000-05) are included in this analysis. The 4^th^ high
values are listed in Table 1-1. Chart 1-3 shows the unusually high
eight-hour ozone concentrations experienced during the 2002 ozone
season.

Chart 1-3

**4^th^ High Eight-Hour Ozone Values for the Tioga County Nonattainment
Area**

## 

![](media/image5.wmf){width="6.260416666666667in"
height="3.7604166666666665in"}

## **C. CLIMATE TRENDS ANALYSIS**

Daily ozone concentrations are heavily influenced by local
meteorological conditions. Ozone is a secondary pollutant formed from
oxides of nitrogen (NO~x~) and volatile organic compounds (VOCs) in the
presence of sunlight. Since ozone chemistry is driven by solar
insolation, peak ozone concentrations generally occur when solar
insolation values are the strongest (mid summer). Chart 1-4 illustrates
the relationship between solar insolation, ozone exceedances and average
monthly temperatures. Exceedances in the Tioga County nonattainment area
occur most frequently in the months of June, July and August (JJA) when
peak solar insolation values and peak temperatures occur.

Chart 1-4

Relationship between Eight-Hour Ozone Exceedances, Solar Insolation and
Temperature

![](media/image6.wmf)

![](media/image7.wmf)![](media/image8.wmf)

1\. Temperature Trends

Temperature trends were examined over the same time period as the ozone
trends to determine if there were similar trends in temperatures and
ozone concentrations. Average temperatures as well as the number of 90º
days from the Canton, PA National Weather Service Cooperative Observer
Program (COOP) station were examined. Canton provides a consistent
reporting site that had proper instrument siting and QA/QC activities
during the time period in question. Data is publicly available from the
National Climatic Data Center.

Chart 1-5 shows Canton's average temperatures from 2000 through 2005.
Average temperature charts for the entire ozone season (Apr 1 through
Oct 21) and JJA are shown. Long-term averages are also included on the
charts to help define which years were warmer or cooler than normal.

Chart 1-5

### Average Temperatures at Canton COOP Station

![](media/image9.wmf)

![](media/image10.wmf)

Ozone concentrations tend to peak during periods of extreme heat. One
way to gauge this effect is to examine the number of 90º days. The more
90º days that occur during an ozone season the better the chance that
ozone concentrations will be high. Higher ozone concentrations could
lead to more exceedances and influence a monitor's 4^th^ high and
consequently its eight-hour ozone design value.

Chart 1-6 graphically displays the number of 90º days at Canton over the
2000-2005 time period. Two graphs are included; one for the entire ozone
season and one for the JJA time frame. Both graphs show Tioga County
experienced an unusually high number of 90° days during 2002. This may
be partially responsible for the unusually high number of eight-hour
ozone exceedances during 2002.

Chart 1-6

### Number of 90º Degree Days at the Canton COOP Station

![](media/image11.wmf)

![](media/image12.wmf)

**2. Precipitation Trends**

Precipitation trends at Canton were analyzed over the 2000-2005 time
period. Precipitation amounts for the entire ozone season and the JJA
time periods were examined. Chart 1-7 graphically shows precipitation
amounts over the 2000-2005 time period.

Chart 1-7

Precipitation Totals (inches) at the Canton COOP Station

![](media/image13.wmf)

![](media/image14.wmf)

## **D. ADDITIONAL TRENDS**

1\. Population Trends

Tioga County has experienced a very slight increase in population over
the last several decades. Tioga County's population has increased
approximately 1% between the 1980 and 2000 Census. It ranks 35^th^ in
the Commonwealth for percentage increase and 34^th^ overall in terms of
gross population change adding 400 people between the 1980 and 2000
Censuses. According to the Bureau of the Census, Tioga County's 2004
estimated population is 41,849 people, ranking the county 54^th^ (out of
67) in the Commonwealth of Pennsylvania.

2\. Economic Trends

Economic trends could have impacts on emissions and thus ozone
concentrations in Tioga County and Pennsylvania. The two factors
considered here include estimated labor force changes in Tioga County
(provided by the Pennsylvania Labor Department) and overall economic
activity in Pennsylvania (measured by the Economic Activity Index
published by the Philadelphia Reserve Bank).

Tioga County's estimated labor force has grown much faster than its
population over the last 25 years. Chart 1-8 shows Tioga County's
population change and estimated labor force change since 1980. A larger
labor force could lead to more driving and increased infrastructure
demands. This in turn could lead to higher emissions. Increases in the
county's labor force also contribute to overall increases in economic
activity (greater family income/spending).

Chart 1-8

Tioga County Population and Estimated Labor Force

![](media/image15.wmf){width="6.750694444444444in"
height="3.7715277777777776in"}

Chart 1-9

Pennsylvania Economic Activity Index from the Philadelphia Federal
Reserve Bank

![](media/image16.wmf){width="5.8125in" height="3.436111111111111in"}

**E. OZONE TRANSPORT**

Ozone transport has a significant affect in the Tioga County eight-hour
ozone nonattainment area. Ozone transport, however, is highly variable
and gauging the effects on design values, exceedances and peak ozone
concentrations is quite difficult because of the large amount of data
that would have to be analyzed.

Tioga County, like most areas of northcentral Pennsylvania, is affected
by several types of ozone transport working on different distance and
time scales. These include large-scale regional transport, short-term
local transport and transport via low-level jets (thin streams of
fast-moving air). Our analysis will look at regional and short-term
transport. The affects of low-level jets are generally not well
understood, though studies in the Philadelphia region have indicated
low-level jets have the potential to transport ozone over significant
distances and influence local ozone concentrations (NEOPS 2003).

## **1. HYSPLIT Trajectory Analysis**

One way to gauge Tioga County's ozone transport possibilities is to
examine air-parcel trajectories during periods of elevated ozone
concentrations. Trajectories from NOAAS's HYSPLIT Trajectory model were
run for each exceedance day between 1999 and 2005. Twenty-four hour back
trajectories were run for 21Z (4 PM EDT) at 500 meters. Twenty-four hour
trajectories for all of the 500-meter trajectories (17 days) were
plotted on a map of the northeastern states (Figure 1-1). The points are
color coded according to the eight-hour ozone concentration on the day
of the trajectory.

Trajectory results indicate a substantial number of upwind trajectories
originated outside of Pennsylvania and the Ozone Transport Region (OTR)
on days when Tioga County's ozone concentrations exceed the eight-hour
ozone standard (see Table 1-2). The bulk of the upwind trajectories
start points lie to the west and south of Tioga County. A couple of the
trajectories exceed 500 kilometers in length. This indicates the
potential for substantial contributions from areas well upwind from
Tioga County.

### Table 1-2

### Summary of Tioga County Trajectory Start Points

**All Exceedance days 1999 through 2005 (17 days)**

  ------------------------------- ------------------------ ---------------
                                  **500 meter**            **%**

  Outside OTR                     13                       76%

  Outside PA                      17                       100%
  ------------------------------- ------------------------ ---------------

### Figure 1-1

**HYSPLIT Back Trajectory Analysis**

![](media/image17.wmf){width="5.979861111111111in"
height="4.618055555555555in"}

## **F. MODELING ANALYSIS**

Modeling results for the EPA's Clean Air Interstate Rule (CAIR) were
examined to determine if the model results support redesignating Tioga
County to attainment. Model results were outlined by the EPA in its
technical support document for CAIR (TSD for Final CAIR, Air Quality
Modeling, 2005). Results for Tioga County indicate modeled ozone
concentrations will be below the eight-hour ozone standard. According to
appendix E, Tioga County's modeled ozone concentrations are \~72 ppb for
both the 2010 Base and 2010 CAIR runs. This result supports
redesignating Tioga County to attainment for the eight-hour ozone NAAQS.

**SECTION 2**

#### SIP APPROVALS AND APPLICABLE REQUIREMENTS

In order for EPA to approve a redesignation of a nonattainment area to
attainment, the applicable State Implementation Plan (SIP) revision must
be fully approved under Section 110(k) of the CAA. In addition, the
state must have met all requirements applicable to the area under CAA
Section 110 and Part D---Plan Requirements for Nonattainment Areas. The
specific requirements applicable to Tioga County can be found in
sections 110(a)(2), and Part D sections 172(c), 173(a), and 176 of the
CAA.

These requirements have been fulfilled for Tioga County. The dates of
EPA approval for regulatory requirements are indicated in parentheses.

A. REGULATORY REQUIREMENTS

The Commonwealth's regulations for Air Resources can be found in 25 *Pa.
Code* subpart C, Article III. Sections are specified below. EPA's
approval of these regulations is codified in 40 CFR Part 52, Subpart NN,
section 52.2020.

-   Correction of deficiencies in pre-1990 existing rules for several
    VOC sources (surface coating, pneumatic rubber tire manufacturing,
    graphic arts and Synthetic Organic Chemical Manufacturing Industry
    equipment leaks) as part of the Reasonably Available Control
    Technology (RACT) fix-up requirement of Section 182. EPA determined
    that Pennsylvania corrected all deficiencies in a December 22, 1994
    final rule (59 FR 65971).

-   Implementation of RACT for all major sources of VOCs not covered by
    the guideline documents for which EPA has defined RACT. Such sources
    included the manufacture of surface-active agents, organic liquid
    cargo vessel loading and ballasting and others. These sources are
    covered by Standards for Sources, Stationary Sources of NOx and
    VOCs, (25 Pa. Code Sections 129.91-129.95)

-   Implementation of RACT for all major sources of NOx. These sources
    of covered by Standards for Sources, Stationary Sources of NOx and
    VOCs, (25 Pa. Code Sections 129.91-129.95).

-   Stationary air pollution sources are subject to the regulations of
    the Commonwealth of Pennsylvania, Pennsylvania Code in Title 25
    Environmental Resources (25 Pa. Code Chapters 121-145). These
    regulations include:

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```
-   Standards of Performance for New Stationary Sources promulgated by
    EPA under the Clean Air Act;

-   Standards for Contaminants (25 Pa. Code Chapter 123)

-   National Emission Standards for Hazardous Air Pollutants (25 Pa.
    Code Chapter 124);

-   Construction, Modification, Reactivation and Operation of Sources,
    including plan approval, prevention of significant deterioration,
    new source review, operating permit program (25 Pa. Code Chapter
    127);

-   Standards for Sources (25 Pa. Code Chapter 129)

-   Annual Emission Statements and required reporting to the Department,
    (25 Pa. Code Chapter 135)

> These permitting, stationary source monitoring and reporting,
> preconstruction review, offset ratios and enforceable emission
> limitations requirements were adopted to implement the federally
> mandated requirements in Sections 110, 172, 173 and 182(a) of the CAA.
> EPA has approved all of these regulations as SIP revisions as
> indicated.

-   The Reasonable Available Control Technology (RACT) provisions in 25
    Pa. Code sections 129. 91-129.95 (relating to Stationary Sources of
    NOx and VOCs) continues to have "limited approval." The Department
    of Environmental Protection (DEP) has submitted SIP revisions to EPA
    for all subject RACT sources.. On June 16, 2006, EPA proposed to
    convert this "limited approval" to a full approval. (71 FR 34864)

-   The Commonwealth adopted and incorporated EPA's general conformity
    rule (40 CFR Part 93, Subpart B) by reference in its entirety. The
    general conformity regulation describes procedures to determine if
    federally-financed, non-transportation projects in nonattainment
    areas are in conformity with air quality plans (25 Pa. Code Section
    127.802).

##### B. NONREGULATORY REQUIREMENTS

-   EPA and the U.S. Department of Transportation (DOT) have issued
    regulations regarding criteria and procedures for demonstrating and
    assuring conformity of transportation improvement programs (TIP or
    program), long range plans (LRP or plan), and individual
    transportation projects with the requirements of the CAA and the SIP
    for the specific nonattainment area. Affected transportation
    planning organizations are complying with all federal laws,
    regulations and guidance for transportation conformity.

-   PADEP has an ongoing program to monitor and analyze ambient air
    quality. PADEP submits ambient air quality to EPA as required. The
    program is conducted in accordance with regulations in 40 CFR Part
    58.

-   PADEP conducts and submits periodic inventories in accordance with
    EPA's Consolidated Emission Reporting Rule (40 CFR Part 51, Subpart
    A).

-   PADEP has adequate personnel funding and authority to carry out the
    implementation of all applicable requirements and provisions of its
    SIP.

# The Tioga County area thus has no pending SIP requirement or obligations for a requirement applicable in this area. In consideration of the above, the applicable implementation plan will have been fully approved by EPA under Section 110 of the CAA and all applicable requirements are fulfilled. 

SECTION 3

DEMONSTRATION OF PERMANENT AND ENFORCEABLE IMPROVEMENT

This section provides an assessment of the ozone precursor emissions at
the time Tioga County was originally designated as nonattainment for
ozone, and at the time when this area attained the 8-hour ozone NAAQS. A
2002 (base year) inventory of VOC and NO~x~ emissions is used to
represent emissions during the ozone nonattainment designation period. A
2004 inventory of VOC and NO~x~ emissions is used to identify ozone
precursor emissions during the period when Tioga County demonstrated
that it attained the 8-hour ozone NAAQS. Detailed information is
presented in the Maintenance Plan by sector.

The section first describes these ozone precursor emission estimates for
this area. These inventories have been developed in accordance with EPA
emission inventory preparation guidance. Then, it presents information
about the permanent and enforceable control measures that have been
implemented in the Tioga area to produce the VOC and NO~x~ emission
reductions that have occurred between these years.

## **A. BASE YEAR (2002) EMISSION INVENTORY**

An emissions inventory for the base year, 2002, was developed for ozone
precursors in accordance with EPA guidance. This year represents the
emissions present when Tioga County did not meet the ozone standard. The
inventory contains information for these sectors:

-   "Stationary sources" (or "point" sources) refer to those sources for
    which the Department collects individual emissions-related
    information. Generally they represent major stationary sources but
    may be smaller.

-   "Stationary area sources" are industrial/commercial/residential
    sources too small or too numerous to be handled individually, such
    as commercial and residential open burning, architectural and
    industrial maintenance coatings application and clean-up, consumer
    product use, and vehicle refueling at service stations. Where there
    is overlap between stationary point sources and stationary area
    sources, the area source values are adjusted to remove any double
    counting.

-   "Highway vehicles" include passenger cars and light-duty trucks,
    other trucks, buses and motorcycles.

-   "Nonroad" covers a diverse collection of engines including outdoor
    power equipment, recreational vehicles, farm and construction
    machinery, lawn and garden equipment, industrial equipment,
    recreational marine, commercial marine vessels, locomotives, ships,
    aircraft and many other applications.

Table 3.1 summarizes emission information for 2002 in tons per summer
day. The Technical Appendices to the maintenance plan contain more
detailed information for each sector including the emissions for 2002 by
source category and annual emissions.

**B. ATTAINMENT YEAR (2004) EMISSION INVENTORY**

A 2004 inventory of VOC and NO~x~ emissions for Tioga County is used to
identify ozone precursor emissions during the period when attainment of
the 8-hour ozone NAAQS was demonstrated. Stationary area sources were
estimated based on 2002 emissions because factors used to develop
emissions were not yet available for 2004.

Table 3.1 summarizes emissions for 2004. The Maintenance Plan describes
how the 2004 inventory was compiled. The Technical Appendices to the
Maintenance Plan contain more detailed information for each sector.

#### Table 3-1

**VOC and NO~x~ Emissions Summary: 2002 and 2004**

  -------------------------- ----------------------- ---------- -------------------
                             **VOC Emissions (tons              
                             per summer day)**                  

  **Major Source Category**  **2002**                **2004**   

  Point Sources              0.5                     0.4        

  Stationary Area Sources    2.8                     2.7        

  Highway Vehicles           3.4                     3.0        

  Nonroad Engines/Vehicles   1.7                     1.7        

  **TOTAL**                  **8.4**                 **7.7**    

                             **NO~x~ Emissions (tons            
                             per summer day)**                  

  **Major Source Category**  **2002**                           **2004**

  Point Sources              1.3                                1.5

  Stationary Area Sources    0.2                                0.2

  Highway Vehicles           5.4                                4.8

  Nonroad Engines/Vehicles   1.5                                1.5

  **TOTAL**                  **8.5**                            **8.0**
  -------------------------- ----------------------- ---------- -------------------

Differences in totals result from rounding. See Technical Appendices for
more details.

**C. Control Measures**

Along with the analysis of ambient air quality and contributing factors
in Section 1 of the redesignation request, this section describes the
measures to which decreases in emissions and thus ozone concentrations
can be attributed from 2002 to 2004. VOC emissions decreased by about
eight percent from 2002 to 2004. NOx emissions decreased by about five
percent from 2002 to 2004.

**1. Stationary Point Sources**

##### Interstate Pollution Transport Reduction. **In response to the Federal NOx SIP call rule, Pennsylvania and other covered states adopted NOx control regulations for large industrial boilers and internal combustion engines, electric generating units, and cement plants. The regulation covering industrial boilers and electric generators required emission reductions to commence May 1, 2003, while the regulation covering large internal combustion engines and cement plants required emission reductions to commence May 1, 2005. While there are no affected units located in Tioga County, upwind NOx reductions from affected sources in Pennsylvania and other states assisted in bringing the area into attainment.** 

## **2. Stationary Area Source Measures**

Solvent Cleaning. Pennsylvania adopted revisions to the volatile organic
compound (VOC) requirements for solvent cleaning operations in 25 *Pa.
Code* Section 129.63 (relating to degreasing operations) that became
effective beginning on December 22, 2001. For heated solvent cleaning
machines, in most respects the provisions of 25 Pa. Code Section 129.63
reflect the technology and operating requirements in the federal maximum
achievable control technology (MACT) requirements for solvent cleaning
machines. Inasmuch as essentially all of the heated solvent cleaning
machines in the Commonwealth use solvents regulated under the MACT, only
a slight VOC emission reduction was achieved by the requirements for
heated solvent cleaning machines. The more important emission reduction
component of the revised solvent cleaning regulation was the requirement
related to solvent vapor pressure for solvent used in cold cleaning
machines. This component of the revised solvent cleaning requirements
resulted in an estimated 66 percent reduction of the VOC emissions from
this category of sources. The provisions requiring the use of low vapor
pressure solvents in cold cleaning machines became effective on December
22, 2002. The emission reductions resulting from this requirement would
be reflected in the 2004 inventory. The regulation was submitted to EPA
as a SIP revision on February 13, 2002. EPA approved the program on
January 16, 2003 (68 FR 2206).

Portable Fuel Containers. Pennsylvania adopted a portable fuel container
regulation, 25 Pa. Code Chapter 130, Subchapter A, to address VOC loss
resulting from permeation through portable gasoline containers,
evaporative loss through container openings, and from spillage during
the filling of small tanks on machines such as lawn mowers, chain saws,
jet skis and the like. This regulation requires that portable fuel
containers manufactured after January 1, 2003 for sale in Pennsylvania
meet certain requirements. (A "sell-through" provision allowed the sale
during 2003 of containers manufactured before January 1, 2003.) The
Department predicted, as part of one-hour ozone SIP demonstrations for
the Southeast Pennsylvania area, that the portable fuel container
regulation would be fully phased in over a 10-year period, i.e.
approximately 10 percent of the existing containers would be replaced
each year. Emission reduction estimates for the program reflect this
phased-in replacement of the containers. The regulation was submitted to
EPA as a SIP revision on March 26, 2003 and approved on December 8, 2004
(69 FR 70983).

**3. Highway Vehicle Sources**

While vehicle miles traveled (VMT) increased approximately one percent
between 2002 and 2004, highway vehicle emissions decreased. These
decreases can be attributed to the Federal Motor Vehicle Control
Programs (an increased proportion of cleaner (federal Tier 1) light-duty
vehicles in the fleet and an increased proportion of cleaner heavy-duty
highway vehicles (federal 1998+ and 2002/2004 standards)).

**Table 3-2**

**VMT and Emissions**

+-----------------+-----------------+-----------------+-----------------+
| #### YEAR       | **VMT**         | **VOC\          | **NOX\          |
|                 |                 | (tpsd)**        | (tpsd)**        |
+-----------------+-----------------+-----------------+-----------------+
| **2002**        | 1,700,882       | 3.4             | 5.4             |
+-----------------+-----------------+-----------------+-----------------+
| **2004**        | 1,724,036       | 3.0             | 4.8             |
+-----------------+-----------------+-----------------+-----------------+

**Federal Motor Vehicle Control Programs (FMVCP).** The emission
reductions from the programs covering fleet turnover are permanent
reductions. The effects of fleet turnover between 2002 and 2004 (that
is, more vehicles subject to tighter tailpipe standards became part of
Pennsylvania's fleet) produced emission reductions between 2002 and
2004.

Tier 1 tailpipe standards established by the CAA Amendments of 1990
include NOx and VOC limits for light-duty gasoline vehicles and
light-duty gasoline trucks. These standards began to be phased in
starting in 1994. Evaporative VOC emissions are also being reduced in
gasoline-powered cars starting with model year (MY) 1998. In 1999, more
stringent new light-duty vehicle standards became effective in the Ozone
Transport Region in 1999 with the National Low Emission Vehicle (NLEV)
Program. Pennsylvania's New Motor Vehicle Control Program regulations
(25 Pa. Code Chapter 126, Subchapter D (relating to new motor vehicle
emissions control program) were approved by EPA on December 28, 1999 (64
FR 72564). These regulations allowed automobile manufacturers to comply
with NLEV instead of the incorporated California Low Emission Vehicle
(CA LEV) requirements through MY 2005. These regulations affected
vehicles 6,000 pounds and less and were the ones in effect for new motor
vehicles in the baseline year, 2002.

In 1999, EPA promulgated regulations more stringent than NLEV (Tier 2),
which were effective starting with MY 2004. The New Motor Vehicle
Control Program (25 Pa. Code Section 126 Subchapter D) adopted in 1998
includes the Pennsylvania Clean Vehicles Program which incorporated the
California Low Emission Vehicle Program by reference. The regulation
allowed automakers to comply with the NLEV program as an alternative to
this Pennsylvania program until MY 2006. In order to participate in
NLEV, Pennsylvania was required to adopt language that extended its
"commitment" to NLEV until MY 2006. Because automobile manufacturers had
to comply with the more stringent regulations (NLEV vs. Tier 2), the
federal Tier 2 program governs new vehicles sold in Pennsylvania in the
attainment year, 2004.

The same EPA regulation required the reduction of sulfur in gasoline
beginning in 2004. In the first year of the program, sulfur levels are
capped at 300 parts per million (ppm) and annual refinery corporate
averages must be no more than 120 ppm. This analysis uses the default
assumptions provided in MOBILE6 for all gasoline parameters for
conventional fuel.

EPA has promulgated national regulations for heavy-duty engines and
vehicles (over 14,000 pounds) starting with MY 2004. In addition, a
consent decree with the major heavy-duty engine manufacturers required,
among other terms, that diesel engines made by these companies comply
with these 2004 standards two model years early, in MY 2002.
Pennsylvania includes these programs, as provided in the MOBILE model,
for the base year 2002 and for 2004.

**Changes to Vehicle Safety Inspection Program.** In December 2003,
Pennsylvania amended its vehicle safety inspection program to include a
visual inspection of certain pollution control components in the 42
counties for which a separate vehicle emissions inspection program is
not required. These regulations can be found in 67 *Pa. Code* Chapter
175. Pennsylvania submitted that portion of the amended safety
inspection program as a revision to its State Implementation Plan on
December 1, 2003. EPA approved the SIP revision on October 6, 2005 (70
FR 58313).

**4. Nonroad Sources**

EPA has adopted a series of regulations affecting new diesel-powered
("compression ignition") and gasoline-powered ("spark ignition") nonroad
engines of various sizes (horsepower) and applications. Information on
these federal rules, including their implementation dates, can be found
at www.epa.gov/nonroad . PADEP used the federal control measure
assumptions built into the NONROAD model to estimate emissions for all
milestone years. No control programs were anticipated to affect aircraft
and railroad locomotive emissions between 2002 and 2004. These programs
are codified at 40 CFR Parts 89-91.

SECTION 4

MAINTENANCE PLAN

The Maintenance Plan for Tioga County is being submitted to EPA for
approval as a SIP revision concurrently with this request for
redesignation. The Maintenance Plan shows that the NAAQS for eight-hour
ozone will be maintained for at least 10 years after redesignation.
Eight years following redesignation, the Commonwealth will submit a
revised plan that ensures attainment through 2028.

In accordance with EPA guidance, the Maintenance Plan shows that
emission levels over the 10 years following redesignation will remain
below the emissions level in 2004, while allowing for growth in
population and vehicle miles traveled. The following state and federal
programs will ensure the continuing decline of VOC and NOx emissions:

-   Clean Air Interstate Rule (CAIR)

-   Interstate Pollution Transport Reduction

-   Portable Fuel Containers

-   Consumer Products

-   Architectural and Industrial Maintenance coatings

-   Federal Motor Vehicle Control Programs (light-duty and heavy-duty)

-   Inclusion of some pollution control components in vehicle safety
    inspection

-   Cleaner gasoline (federal program)

-   Cleaner highway diesel (federal program)

-   Cleaner nonroad diesel (federal program)

-   Pennsylvania Clean Vehicle Program

##### Pennsylvania Heavy-Duty Diesel Emissions Control Program

-   Federal programs for nonroad engines

PADEP has provided assurances that it will continue to operate the
ambient air quality monitoring network in order to track maintenance of
the standard and to evaluate emissions inventories periodically compared
to the projections provided in the plan. DEP has also provided a list of
potential contingency measures that it would consider to correct any
violation of the eight-hour ozone NAAQS that occurs after redesignation
of the area.

## **ACRONYMS AND ABBREVIATIONS**

CAA Clean Air Act

CAIR Clean Air Interstate Rule

CA LEV California Low Emission Vehicle (program)

DOT Department of Transportation (U.S.)

EPA U.S. Environmental Protection Agency

FMVCP Federal Motor Vehicle Control Program

I/M Inspection and Maintenance

JJA June, July and August

NAAQS National Ambient Air Quality Standard

NLEV National Low Emission Vehicle (program)

NEOPS North East Oxidant and Particle Study

NO~x~ Oxides of Nitrogen

OTR Ozone Transport Region

PADEP Pennsylvania Department of Environmental Protection

ppb parts per billion

ppm parts per million

RACT Reasonably Available Control Technology

SIP State Implementation Plan

TSD Technical Support Document

tpsd tons per summer day

VMT Vehicle Miles Traveled

VOC Volatile Organic Compound