Supplemental Air Quality Analysis
TRANSPORTATION
CONFORMITY ANALYSIS
Cabell and Wayne Counties
Prepared By:
KYOVA Interstate Planning Commission
400 Third Avenue Avenue
Huntington, West Virginia
Introduction............................................................................................ 1
Interagency Consultation....................................................................... 2
Methodology........................................................................................... 2
Results.................................................................................................... 3
Introduction
EPA has approved a redesignation request and a State Implementation Plan (SIP) revision for the Huntington portion of the Huntington-Ashland, WV-KY from nonattainment to attainment of the 8-hour ozone National Ambient Air Quality Standard (NAAQS). The West Virginia Department of Environment Protection (WVDEP) requested that the Cabell and Wayne Counties, West Virginia (Huntington) portion of the Huntington-Ashland area be redesignated as attainment for the 8-hour ozone NAAQS. The Huntington-Ashland 8-hour ozone nonattainment area is comprised of three counties (Cabell and Wayne Counties, West Virginia and Boyd County, Kentucky). EPA proposed the approval of the ozone redesignation request for the Huntington portion of the Huntington-Ashland area.
In conjunction with its redesignation request, the WVDEP submitted a SIP revision consisting of a maintenance plan for Huntington that provides for continued attainment of the 8-hour ozone NAAQS for the next 12 years. EPA is made a determination that Huntington has attained the 8-hour ozone NAAQS based upon three years of complete, quality-assured ambient air quality ozone monitoring data for 2003-2005.
As a result, KYOVA Interstate Planning Commission (KYOVA) has developed a supplemental Air Quality Conformity Analysis, in accordance with federal requirements, for the 2030 Long Range Transportation Plan (LRTP) and the Transportation Improvement Program (TIP) for the Huntington-Ironton Metropolitan Area. KYOVA has completed this work pursuant to the Clean Air Act of 1990 and the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU), and in cooperation with the West Virginia Department of Transportation, Ohio Department of Transportation, Federal Highway Administration (FHWA), Federal Transit Administration (FTA) and The Transit Authority (TTA).
The TIP and LRTP for the Huntington-Ironton Metropolitan Statistical Area (all of Cabell and Wayne Counties in West Virginia and the urbanized area of Lawrence County, Ohio) includes priority projects and programs for which implementation is anticipated in the next four fiscal years (FY 2008, FY 2009, FY 2010 and FY 2011). More specifically, the TIP describes all highway and transit (both capital and operating) maintenance and new capacity; and bicycle and other transportation projects for which federal funding is anticipated and provides a financial plan for implementation. The TIP also includes estimates of available Federal Transit Administration (FTA) funds for vans to serve the elderly and handicapped. Furthermore, the TIP will satisfy the Program of Projects (POP) requirements of the Federal Transit Administration.
Historically, On June 15, 2004, a new eight-hour ozone National Ambient Air Quality Standard (NAAQS) became effective.
The maintenance plan has established mobile source emission budgets (tons per summer day) for volatile organic compounds (VOC) and nitrogen oxides (NOx) for future years. NOx and VOC emissions are ozone precursors - they are the necessary ingredients for the formation of ozone.
The 8-hour mobile source SIP emissions maintenance budgets were printed on July, 2006 in the Federal Register (50 FR 3918) for the Huntington metropolitan area (Cabell and Wayne Counties), the motor vehicle emissions budgets for year 2009 are 4.6 tons/day of volatile organic compounds (VOC's) and 8.7 tons/day of nitrogen oxides (NOx). For year 2018 the motor vehicle emissions budgets are 3.0 tons/day of volatile organic compounds (VOC's) and 4.1 tons/day of nitrogen oxides (NOx).
The planning horizon years included in this analysis are 2009 (the attainment year for the eight-hour standard), 2015, 2018, 2025 (interim years) and 2030 (the last year of the transportation plan), as required by 40 CFR 93.118.
Interagency Consultation
The models, methodology and procedures for this conformity analysis were determined through an interagency consultation process that involved representatives from the KYOVA Interstate Planning Commission, the West Virginia Department of Transportation (WVDOT), the West Virginia Division of Air Quality (DAQ), the Federal Highway Administration (FHWA), the United States Environmental Protection Agency (USEPA) and the Ohio Department of Transportation (ODOT).
Methodology
In general, the methodology for analyzing the NOx and VOC emissions for the Huntington area involved the following steps:
(1) The KYOVA travel demand model that has a base year of 2000 and reflects the KYOVA 2030 Long Range Transportation Plan, was used to determine vehicle-miles of travel (VMT) in Cabell and Wayne Counties. VMT was calculated for twelve facility types, including interstates, freeways and expressways, other principal arterials, minor arterials, collectors, and local roads in urban areas, and interstates, principal arterials, minor arterials, major collectors, minor collectors, and local roads in rural areas, for the following horizon years: 2009, 2015, 2018, 2025, and 2030. 2018 VMT by functional class interpolated between 2015 and 2020
(2) The VMT data from the base year of the model (2000) were compared to Highway Performance Monitoring System (HPMS) VMT data for the same year provided by the West Virginia DOT. This was done to determine if the model data needed to be adjusted to account for under-representation of certain functional classifications in the model network. For example, many local roads are not explicitly included in the model network, but emissions from vehicles on these facilities still need to be included in the analysis. Adjustment factors were calculated based on the model base year, which were then applied to all future year model projections to determine final VMT estimates to be used for emissions calculations. Factors supplied by WVDOT were used to adjust the model data for a typical summer day VMT.
(3) The MOBILE6.2 mobile source emissions model was used to determine VOC and NOx emissions factors for each roadway class and horizon year. MOBILE6.2 inputs for external conditions, gasoline Reid vapor pressure, and inspection/maintenance and anti-tampering programs were the same as those used in the MOBILE6.2 input files provided by the West Virginia Division of Air Quality (DAQ), which were used to determine the SIP budgets.
To determine the VMT mix percentages for use in the MOBILE6.2 model, the split between heavy-duty vehicles and light-duty vehicles in the Huntington area was calculated for each facility type based on HPMS data from the West Virginia DOT. This split was applied to the MOBILE 6.2 default VMT mix so that the VMT mix used to determine emissions factors would be more closely aligned with local characteristics. HPMS data cannot be used directly in the MOBILE6.2 model, because the vehicle classification schemes are not the same. This is the procedure recommended in the EPA Technical Guidance on the Use of MOBILE6 for Emission Inventory Preparation.
(4) Using the projected VMT totals and the MOBILE6.2 emissions factors, area-wide NOx and VOC emission totals were calculated and compared to the SIP emissions budgets.
Results
The results of the analysis, shown in Table indicate that the future area-wide mobile source emissions of NOx and VOC will be less than the emissions budgeted in the maintenance plan. The emissions listed in Table are in tons per summer day.
Table 1
Projected VOC and NOx Emissions
Year |
VOC (tons per day) |
NOx (tons per day) |
||
Budget |
Modeled |
Budget |
Modeled |
|
2005 |
13.4 |
5.3 |
13.9 |
10.6 |
2009 |
4.6 |
4.0 |
8.7 |
7.6 |
2015 |
13.4 |
2.8 |
13.9 |
4.1 |
2018 |
3.0 |
2.62 |
4.1 |
3.59 |
2025 |
13.4 |
2.2 |
13.9 |
2.4 |
2030 |
13.4 |
2.3 |
13.9 |
2.2 |
As demonstrated in the preceding analysis, the projected mobile source emissions will be less than the allotted budget through the year 2030. Therefore, the Transportation Plan conforms to the new 8-hour ozone NAAQS. The Huntington- Ironton Area Transportation Study 2008 - 2010 Transportation Improvement Program (TIP), which consists of a subset of projects from the Long Range Transportation Plan, also conforms to the 8-hour ozone NAAQS.
AIR QUALITY
CONSIDERATION
The West Virginia portion of the area, Cabell and Wayne counties
are currently designated as an ozone attainment areas. The U.S. EPA
published the redesignation of the area to attainment status in the
December 21, 1994 edition of the Federal Register. This rule became
effective on December 27, 1994.
Even though the redesignation has been granted the emission will
continue to be monitored. From the transportation system perspective,
this redesignation lessens the burden of emission analysis. The area
will continue to be subject to emission budgets established in the
Maintenance Plan which is part of the redesignation package.
BACKGROUND
In 1991, Cabell and Wayne Counties, West Virginia, were designated
as moderate non-attainment areas for ozone. This designation was made
as result of monitored exceedances of the National Ambient Air quality
Standards (NAAQS) identified by the West Virginia Office of Air Quality
and US Environmental Protection Agency. Lawrence County is designated
as attainment, therefore the CAAA requirements do not impact transportation
planning in that portion of the study area.
Each state has an agency responsible for overseeing compliance
with Clean Air regulations. In West Virginia, it is the Division of
Environmental Protection, Office of Air Quality (WVOAQ). They prepare,
and from time to time amend, the State Implementation Plan (SIP). The
SIP is an air quality management plan that provides measures for controlling
all sources of air pollution. As the result of an amendment to the
SIP, the US EPA issued a final rule redesignating Cabell and Wayne
Counties, West Virginia as attainment for ozone on December 21, 1994.
Concurrently, the US EPA approved a maintenance plan for the Huntington
area as an amendment to the State Implementation Plan (SIP) including
contingency measures which provide for continued attainment of the
ozone NAAQS.
Ozone is not directly emitted into the air. Rather it is formed
when Volatile Organic Chemicals (VOC) and Nitrous Oxides (NOX) react
in sunlight. Emissions of VOC and NOX are considered precursors of
ozone and, therefore, are regulated. Sources of VOC and NOX are broken
down into three categories: mobile, stationary and area sources. Mobile
sources include emissions from all vehicles on the road. Large measured
sources, such as industrial plants, are considered stationary sources.
Area sources include small unmeasured sources, off-road vehicles, lawn
mowers, refueling, bio-genic sources, etc.
The maintenance plan referenced above establishes a "budget" of
emissions that can come from each of these sources while still meeting
National Ambient Air Quality Standards. For the transportation plan,
we are concerned with mobile emissions.
AIR QUALITY ANALYSIS
TRANSPORTATION
CONFORMITY ANALYSIS
CABELL AND WAYNE COUNTIES
Introduction
The Huntington, West Virginia metropolitan area (including Cabell and
Wayne Counties) was redesignated from a moderate ozone nonattainment area
to an attainment area in December 1994. In accordance with the Clean
Air Act Amendments of 1990, proposed transportation projects in the Huntington-Ironton
Area Transportation Plan should help maintain the attainment status for
all future years.
As a recently redesignated attainment area, Cabell and Wayne Counties
are subject to an emissions budget contained in the State Implementation
Plan (SIP) maintenance plan. The maintenance plan has established mobile
source emission budgets (tons per summer day) for carbon monoxide (CO),
volatile organic compounds (VOC), and nitrogen oxides (NOx) for future years.
NOx and VOC emissions are ozone precursors – they are the necessary ingredients
for the formation of ozone. In November 2001, the West Virginia
Department of Environmental Protection, Division of Air Quality (DAQ)
revised the SIP budgets for NOx and VOC. This budget revision has
been submitted to the United States Environmental Protection Agency (EPA)
and has been determined to be administratively and technically complete.
This conformity analysis compares the future NOx and VOC mobile source
emissions to the revised SIP maintenance plan budget. The analysis
methodology is based on a protocol memorandum that was disseminated to
KYOVA, DAQ, EPA, the West Virginia Department of Transportation, Division
of Highways (WVDOH), and the Federal Highway Administration (FHWA).
The analysis protocol was reviewed by the stakeholders, and modifications
were made based on comments received. A copy of the final protocol
memorandum, which received concurrence from all stakeholders, is included
in the Appendix. The analysis was conducted with ongoing coordination
among KYOVA, DAQ, EPA, WVDOH, and FHWA.
Methodology
In general, the methodology for analyzing the NOx and VOC emissions
involved the following three steps:
(1) The projected vehicle-miles of travel (VMT) in
Cabell and Wayne Counties was determined for the horizon years: 2002,
2005, 2015, and 2025. To determine VMT for each of the road classifications,
the following procedure was used:
§ Historic (1980 to 1998) VMT data by roadway
type for Cabell and Wayne Counties was provided by the West Virginia Department
of Transportation (WVDOT). VMT was observed to increase linearly
between 1980 and 1998. This growth trend was extrapolated to obtain projected
2002, 2005, 2015, and 2025 no-build traffic volumes.
§ Future build and no-build volumes for each
of the roadways affected by projects in the Long-Range Transportation Plan
were forecasted by KYOVA for two future years (see Appendix). In these
future VMT calculations, KYOVA also took into account the Chesapeake Bypass
in Lawrence County, the bicycle path from Kenova to Huntington, and the
Huntington Intermodal Facility.
§ Build and no-build volumes for the roadways
affected by projects in the Long-Range Transportation Plan were interpolated
for the remaining analysis years.
§ The projected VMT for each horizon year was
adjusted to account for the implementation of projects (including transit
projects) in the Long-Range Transportation Plan.
(2) The MOBILE5a mobile source emissions model was
used to determine VOC and NOx emission factors for each roadway class
and horizon year. In keeping with the latest planning assumptions,
registration data developed for use with MOBILE6 was used to determine
the age distribution of the vehicle fleet. MOBILE5a defaults were
used for mileage accumulation by vehicle age. The MOBILE5a emission
factors include adjustments for the National Low Emission Vehicle (NLEV)
standards for light-duty gasoline-fueled vehicles, as described in EPA
MOBILE5 Information Sheet #6.
Off-model adjustments were made to the emission factors calculated
by MOBILE5a to estimate the benefits of the Tier 2 Motor Vehicle Emissions
Standards and Gasoline Sulfur Control Requirements. These adjustments
were made in accordance with the procedure described in EPA MOBILE5 Information
Sheet #8.
(3) Using the projected VMT totals and the MOBILE5a
emission factors, area-wide NOx and VOC emission totals were calculated
and compared to the maintenance plan emissions budgets. Since MOBILE5a
only calculates emission factors through 2020, emission totals for 2025
were calculated using 2020 emission factors and 2025 VMT projections.
MOBILE5a is a mobile source emission factor model developed by the
EPA. The model estimates VOC and NOx emissions as a function of
speed, temperature, maintenance programs, altitude, and several other
factors. NOx and VOC emissions are closely related to speed.
In general, NOx emissions decrease as vehicle speeds approach 21 miles
per hour. Between 21 and 45 miles per hour, NOx emissions stay constant.
Above 45 miles per hour, NOx emissions increase. VOC emissions tend
to decrease as speed increases.
Conformity
As demonstrated in the preceding analysis, the projected mobile source
emissions will be less than the revised SIP maintenance budget through
the year 2025.
APPENDIX
§ Analysis Protocol Memorandum
§ Long-Range Transportation Plan
Build/No Build Traffic Volumes
§ Emission Spreadsheets
§ MOBILE5a Input/Output Files
For more information Contact
Saleem A. Salameh, P.E.