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FHWA → Environment → Air Quality → Conformity → Practices → Corridor X

PM_2.5 PROJECT LEVEL CONFORMITY DETERMINATION FOR CORRIDOR X

7. PM_2.5 Hot-Spot Analysis

The Corridor X/ I-65 project meets the criteria set forth in 40 CFR 93. 123(b) (1) for projects of air quality concern primarily because it is a new highway facility and an improvement to an existing facility with a significant level of or significant increase in diesel vehicles. Therefore a qualitative hot-spot analysis is required.

A. Analysis Method

The interagency consultation group recommended developing the qualitative analysis based upon existing air quality studies. The air quality study utilized, "Particulate Matter Sources in Birmingham, Alabama" was completed in 2006. As the analysis proceeded it was determined that the Leeds site and the Hoover site could be used as comparison sites.

B. Data Considerations

To perform the required qualitative analysis the following items have been considered.

1. Road dust emissions or construction dust emissions, and PM_2.5 control measures;
2. Project area traffic and regional trends;
3. Recently completed air quality study concerning the origins of fine particles (PM_2.5) and local meteorology
4. The year or years of peak emissions for the project; and
5. Comparison sites.

C. Other PM_2.5 Considerations

The Conformity Rule requires PM_2.5 hot-spot analyses to include road dust emissions only if such emissions have been found significant by EPA or the state air agency prior to the PM_2.5 SIP or as part of an adequate PM_2.5 SIP motor vehicle emissions budget (40 CFR §93.102(b)(3)). EPA has not approved a PM_2.5 SIP for Birmingham Area PM_2.5 nonattainment area, nor has EPA or the state air agency made any significance findings related to re-entrained road dust for the PM_2.5 nonattainment area. Therefore reentrained road dust is not considered in the analysis, per the Conformity Rule. In addition, as there is not an applicable PM_2.5 SIP for this area, there are no PM2.5 control measures; and the project is in compliance with 40 CFR 93.117. Construction-related emissions for the project are considered to be temporary, as the construction will be less than five years at any one site, meeting the criteria of section 93.123(c)(5). Therefore, construction emissions are not required to be analyzed.

D. Traffic Conditions

As described earlier, this segment is part of a much larger project that completes Corridor X and impacts the regional transportation system. Exhibit 7, Area Traffic Patterns is a display of a select link analysis performed using data from transportation demand model runs for the year 2015. 2015 is the first horizon year in the SIP in which the project is open to traffic in the travel demand model runs which determined conformity of the 2030 Long-Range Transportation Plan and the 2006-2008 Transportation Improvement Program using the interim "no greater than baseline test. This analysis was done to show the travel patterns, areas of highest traffic volumes, changes between build and no build and the effective levels of service under each condition. An additional part of the analysis was to assemble traffic count data from stations along Interstate 65 and within the project area to examine the past ten years (1995 - 2005) of traffic counts to determine an area growth rate and identify the percentage of diesel trucks. Traffic count data collected classifies first a percentage of commercial vehicles (TADT), composed of trucks of all types, expressed as a percent of AADT and then a percentage of heavy duty trucks, trucks with three or more axles expressed as a percentage of TADT.

The following table, Exhibit 6, Station Locations, shows the key location on the map, Exhibit 7, where traffic volumes (AADT) were analyzed for the North Birmingham area.

Location	ID
I -65 Near Finley Blvd.	A
I-65 Near 33/32 Street	B
I-65 Near 41st Ave.	C
I-65 Near Corridor - X	D
I -65 Near US 31	E
US 78Near I-20/59 Junction	F
US 78 Near Daniel Payne Dr.	G
Corridor-X Traffic Assignment	H

Exhibit 6: Station Locations

To get precise results about traffic volumes for the future years a Select Link Analysis was utilized. Select Link Analysis has the following advantage over conventional traffic model analysis.

• Select Link Analysis shows where the traffic is coming from and where it is going to on a selected link (in our case link on I-65 near Finley Blvd. was selected and a link on US 78 near I-20/59 interchange was selected). Select Link Analysis is useful in understanding travel patterns.

• All traffic volume assignments shown on the spreadsheet for the year 2015, Exhibits 8 and 9 (Build and No Build), are from the Select Link Analysis.
  
  

Exhibit 7: Area Traffic Patterns

Traffic volumes for I-65 and US-78 for year 2015 from the traffic model were used to analyze the travel patterns. Build and no build variations of the Birmingham traffic model using Select Link Analysis were run for 2015. Assignments produced by Select Link Analysis were analyzed and tabulated for all the locations including Corridor X (build scenario) shown on the map. Peak hour traffic percentage (K), directional factor (D), percent trucks (TDHV) and medium trucks (MT) and heavy trucks (HT) factors are also shown for the no build scenario for the locations in Exhibit 8, No Build Scenario, including a comparison of the traffic volume to the capacity and a determination of the level of service. Capacity of the roadway was calculated from the highway capacity manual by taking into account all the factors (speed, number of lanes, % trucks, K and D) associated with roadway. Exhibit 9, Build Scenario, displays the same data for the build scenario.

No Build 2015	Locations
Traffic Data	A	B	C	D	E	F	G	H
# of Lanes in Each Direction	3	3	3	NA	3	2	2	NA
Speed (mph)	70	70	70	NA	70	55	55	NA
K	10	10	10	NA	10	10	10	NA
D	60	60	60	NA	60	55	55	NA
TDHV	10	11	12	NA	13	5	7	NA
TADT	13	15	16	NA	17	7	9	NA
MT	25	20	20	NA	20	40	34	NA
HT	75	80	80	NA	80	60	66	NA
Traffic Assignments	139,268	129,324	120,578	NA	108,010	57,009	48,566	NA
Capacity of the Roadway	74,800	74,800	74,800	NA	74,800	35,000	35,000	NA
Volume/Capacity Ratio	1.86	1.73	1.61	NA	1.44	1.63	1.39	NA
Level of Service	F	F	F	NA	F	F	F	NA

Exhibit 8: No Build Scenario

Build 2015	Locations
Traffic Data	A	B	C	D	E	F	G	H
# of Lanes in Each Direction	6	6	6	6	6	2	2	3
Speed (mph)	70	70	70	70	70	55	55	70
K	10	10	10	10	10	10	10	10
D	60	60	60	60	60	55	55	60
TDHV	10	11	12	12	13	5	7	7
TADT	13	15	16	16	17	7	9	9
MT	25	20	20	20	20	40	34	N/A
HT	75	80	80	80	80	60	66	N/A
Traffic Assignments	165,388	162,445	157,728	153,148	120,343	24,289	9,068	47,845
Capacity of the Roadway	180,000	180,000	180,000	180,000	180,000	35,000	35,000	55,000
Volume/Capacity Ratio	0.92	0.90	0.88	0.85	0.67	0.69	0.26	0.87
Level of Service	C	C	C	C	B	B	A	C

Exhibit 9: Build Scenario

The following observations were made based on the results of Select Link Analysis. Traffic volume growth on I-65 and US 78 was same as predicted above (3.5% and 2.5%) with and without Corridor X project.

• Combining traffic volumes of locations A and F for both no build (139,268 +57,009 = 196,277) and build (165,388 + 24,289 = 189,687) scenarios shows nearly same amount of projected traffic volumes for the year 2015.

• Under the build scenario the traffic volumes on US 78 drop considerably, with the traveling public taking the available alternate freeway facility (Corridor X). And, comparing traffic volumes of location H for the build scenario (47,845) and location G for No Build (48,566) scenario demonstrates the traffic shift to Corridor X from US 78.
• A volume over capacity analysis for I-65, US 78 and Corridor X in the build scenario demonstrates a significantly improved traffic flow on all segments. The build scenario shows the V/C ratio for all locations is below 1.0 and level of service is improved to from F to C for I-65 and from F to B for US 78. This represents a marked improvement in LOS throughout the area transportation system.

The traffic numbers shown below in Exhibit 10, Factored Traffic include the expected effects form the opening of Corridor X, that is, the increase in I-65 traffic and the decline in traffic along US 78. In examining the modeling data developed through the selected link analysis it is observed that the traffic coming into the area via US 78 from the west, travels US 78 and accesses I-65 from either 41st Ave. or Finley Blvd. These vehicles currently travel the surface streets. Subsequent to the opening of Corridor X they will now continue on into Birmingham from the west on Corridor X prior to accessing I-65. The locally generated traffic will follow a path of accessing I-65 at 32nd Ave and 41st Ave. to head north on I-65 prior to heading west on Corridor X.

Station	Location	From	To	2012	2014	2015	2030	% Trucks	% Heavy
A	I-65	16th St	Finley Ave	149,171	159,796	165,388	277,083	13%	75%
			# Trucks	19,392	20,775	21,501	36,021
B	I-65	Finley Ave	32nd Ave	146,516	156,951	162,445	272,151	15%	80%
			# Trucks	21,977	23,543	24,367	40,823
C	I-65	32nd Ave	41st Ave	142,261	152,394	157,728	264,249	16%	80%
			# Trucks	22,762	24,383	25,236	42,280
D	I-65	41st Ave	US 31	138,130	147,968	153,147	256,575	17%	80%
			# Trucks	23,482	25,155	26,035	43,618
E	I-65	US 31	Walker Chapel Rd	108,543	116,274	120,344	201,618	18%	80%
			# Trucks	19,538	20,929	21,662	36,291
F	US 78	Finley Ave	159	22,555	23,697	24,290	35,179	7%	60%
			# Trucks	1,579	1,659	1,700	2,463
G	US 78	East of CX	Finley Ave	8,415	8,841	9,062	13,124	7%	60%
			# Trucks	589	619	634	919
H	CX	West of 1 65	I 65	43,154	46,228	47,846	80,159	9%	60%
			# Trucks	3,884	4,161	4,306	7,214

Exhibit 10: Factored Traffic

Initially reviewing this project an observer would expect the highest volumes and truck percentages to occur within the route interchange; however an assessment of current and future traffic patterns supports a determination that the section of Interstate 65 between 41st Ave and US-31 (Station D) and south of the Corridor X/ I-65 route interchange is the location with the highest level of diesel traffic. This segment was chosen as the analysis location because it has the highest level of diesel traffic.

Using the volumes in Exhibit 10, Factored Traffic and the location information displayed in Exhibit 6, Station Locations as a reference, as well as the build/no-build comparison in Exhibits 8 and 9, a qualitative discussion of the traffic patterns and conditions follows.

Station A is located between 16th street Interchange and Finley Boulevard. The 16th street interchange only allows movements from I-65 northbound and to I-65 southbound. It is primarily a local access to and from the adjoining neighborhoods and traffic at this interchange does not contribute to upstream volumes.

Station B is located between Finley Blvd. and 32nd Ave. with the interchange accessing Finley Blvd. to a multimodal facility, truck stop and industrial and commercial activities to the west along US 78. These types of interchanges contribute to the higher percentage of trucks in this segment while registering lower traffic volumes.

Station C is located between 32nd Ave and 41st Ave. This segment was chosen as the hot spot location because it has the highest level of diesel traffic. The mainline traffic volumes are increased by the southbound movements from 41st Ave. The area west of I-65 is the location for multiple truck transfer centers and trucking company regional headquarters. The 32nd Ave northbound ramp provides access from the industrial activities east of I-65 for northbound freight movements

Station D is located between 41st Ave. and US-31 just south of the designed interchange. Historical traffic volumes and computer modeling show lower overall traffic volumes but a higher number of trucks along this segment. Traffic modeling shows movements from Corridor X to I-65 south are three times higher than movements from Corridor X to I-65 north. . A combination of overall traffic volumes and the percentage of truck volumes qualitatively establish this area as the worst case location.

Station E is located between US-31 and Walker Chapel Rd. Traffic modeling and observed traffic counts show lower traffic volumes north of the designed interchange.

Station F is located between Finley Ave and I-59/20. The select link analysis shows markedly lower traffic volumes after the opening of Corridor X.

Station G is located west of Finley Avenue. The select link analysis shows markedly lower traffic volumes after the opening of Corridor X.

Station H is located on Corridor X west of the interchange with Corridor X, using the 3.55 growth rate established through the traffic modeling; this traffic has been estimated through 2030.

In summary, the primary movement within the interchange will be from Corridor X to I-65 south. Traffic numbers attributable to multi axel vehicles (trucks) will be at its greatest number in the segment between 41st Ave and US-31 (Station D). And the numbers do point to an increase in VMT, but as shown below in Exhibit 11, Congested VMT, from the Birmingham Area Long Range Transportation Plan shows congestion levels (percentage of roadway segments with a V/C ratio greater than 1.2) will decrease through the 2030 model year.

Exhibit 11: Congested VMT

E. Air Quality Studies

There are currently 17 monitors throughout the non attainment area, Exhibit 12, Air Quality Monitors, identifies those locations. The project lies within the one mile and two mile buffer range of the North Birmingham monitor. The North Birmingham monitor can be considered as within proximity of this project.

Exhibit 12: Air Quality Monitors

The Jefferson County Department of Health calculated the average PM_2.5 concentrations according to EPA guidance. The Birmingham community monitoring zone (CMZ) is the mean of the North Birmingham and Wylam averages. The Birmingham CMZ average of 16.8 for 2004³ is shown in Exhibit 13, CMZ PM_2.5 Concentration Values. The two sites in Jefferson County, AL are encompassed in a community Monitoring Zone (i.e. utilize spatial averaging); the spatially averaged design value for the CMZ for 2004 was 16.8. This means that between the North Birmingham and Wylam monitors the observed concentration values in micrograms per cubic meter [ug/m³]) at the two sites was averaged and the resulting value was 16.8 in 2004.

Site	1999	2000	2001	2002	2003	2004
NBHM	23.4	22.3	19.1	17.5	17.4	17.7
Wylam	21.3	20.7	17.9	16.6	15.6	15.9
CMZ	22.4	21.5	18.5	17.0	16.5	16.8

Exhibit 13: CMZ PM 2.5 Concentration Values⁴

Exhibit 14: Multiyear PM 2.5 Design Values, shows the average of the design values for multiple three year periods from 2000-02, 2001-03, and 2002-04 (also known as the weighted average design value). A design value is a statistic that describes the air quality status of a given area relative to the level of the National Ambient Air Quality Standards (NAAQS). Design values are calculated and published annually by EPA's Office of Air Quality Planning and Standards and reviewed in conjunction with the EPA Regional Offices. Design values are expressed as a concentration instead of an exceedance count, thereby allowing a direct comparison to the level of the standard.

Exhibit 13 shows actual concentrations of PM _2.5 at the North Birmingham and Wylam sites and Exhibit 14, Multiyear PM _2.5 Design Values show the measurement standard for the entire area as set by the EPA.

Site	1999-2001	2000-2002	2001-2003	2002-2004
NBHM	21.6	19.6	18.0	17.5
Wylam	20.0	18.4	16.7	16.0
CMZ	20.8	19.0	17.3	16.8

Exhibit 14: Multiyear PM 2.5 Design Values⁵

In order to more accurately determine the source of particle emissions contributing to the measured concentration, a study was completed in 2006 for Alabama Department of Environmental Management and the Jefferson County Department of Health. The study used data available through 2004.

The study "Particulate Matter Sources in Birmingham, Alabama" (Blanchard, et al) examined the sources of airborne particles at two Birmingham air quality monitoring sites, located in North Birmingham (NBHM) and Wylam (WYL). These two sites had shown high airborne particle concentrations relative to other sites in urban and non-urban portions of Jefferson County, Alabama.

The annual average concentrations of fine particulate matter (fine PM, or particulate matter less than 2.5 micrometer (µm) aerodynamic diameter, PM_2.5) at NBHM and WYL exceeded the current National Ambient Air Quality Standard (NAAQS) (annual average of 15 micrograms per cubic meter [ug/m³]). A more accurate analysis of the source of the particulate matter would aid in the development of the State Implementation Plan (SIP) for reduction of PM_2.5 concentrations that must be submitted to the U.S. Environmental Protection Agency (EPA) by April 2008. The SIP must identify specific fine particle emission control measures that will be implemented and that will allow NBHM and WYL to attain the fine PM NAAQS by the 2010 attainment target.

The PM chemical composition at WYL and NBHM indicates that the mixture is similar to that found at regional and non-urban sites, except that additional carbon (as organic carbon and elemental carbon) is found at NBHM and WYL, along with certain metal concentrations, at substantially higher concentrations than in other cities. Modeling studies project that the regional and general urban components of PM_2.5 will decline by about 1 ug/m³ over the next several years with reduction in sulfate, nitrate, and carbon concentrations, as a result of controls on emissions of sulfur dioxide (SO2) and oxides of nitrogen (NOx= NO + NO₂) applied to large stationary sources and of controls on transportation emissions of NOx, SO2, and primary PM (cleaner gasoline and diesel vehicles).

The study indicates that the Birmingham area resides in a larger region having high annual-average PM_2.5 concentrations of 12 to 14 ug/m³, which approaches the ambient air quality standard of 15 ug/m³ annual average. Superimposed on the regional levels is a diffuse urban concentration increment of approximately 2 ug/m³. In the case of NBHM and WYL, an additional highly localized increment of 3 to 4 ug/m³ is present. In examining the sources contributing to the latest non spatially averaged measured PM_2.5 concentrations at the NBHM monitor (17.7 ug/m3), between 67% and 79% comes from background concentrations, 11% comes from an urban concentration, and highly localized sources account for between 17% and 22%.⁶

The "Particulate Matter Sources in Birmingham, Alabama" study produced some interesting results. In examining the major species concentrations at Birmingham sites the most striking finding was the concentrations of zinc, whose average concentrations are two orders of magnitude greater at NBHM and WYL than at any other location. Zinc, therefore, is a chemical marker for emissions that are largely unique to Birmingham. Since mobile source emissions are common to all cities, zinc emissions in Birmingham probably derive from specific industrial processes occurring there.

It is possible but not likely that certain mobile-source emissions would be unique to Birmingham. Other species found at higher concentrations at the Birmingham sites are calcium, copper, chromium, iron, manganese, sodium, and lead. All suggest the presence of specific emission sources that influence local PM levels in Birmingham.⁷ The comparison is show below in Exhibit 15, Species Analysis, which shows the relationship between the North Birmingham and Wylam monitors and five other southeastern cites with populations over 500,000.

Species	Site (AQS code)
	N. Birmingham AL 010730023	Birmingham (Wylam) AL 010732003	Augusta GA 132450091	Jackson MS 280490018	Memphis TN 471570047	Nashville TN 470370023	Atlanta GA (Jefferson St.) SEARCH
Fine Mass	17.9	16.5	14.9	13.1	13.7	14.5	15.8
OC*	6.5	5.1	5.3	4.9	4.8	3.9	4.2
EC*	1.4	0.7	0.6	0.7	1.0	0.6	1.4
EC/OC*	0.2	0.14	0.1	0.14	0.2	0.16	0.33
Sulfate	4.7	4.7	4.9	3.6	3.8	4.4	4.4
Nitrate	1.1	1.0	0.8	0.9	1.6	1.3	1.0
Ammonium	1.6	1.4	1.5	1.2	1.5	1.5	2.1
Aluminum	0.04	0.04	0.04	0.03	0.03	0.04	0.11
Bromine	0.005	0.005	0.004	0.003	0.003	0.004	0.004
Calcium	0.14	0.09	0.03	0.04	0.07	0.09	na
Copper	0.01	0.01	0.002	0.002	0.003	0.003	0.003
Chlorine	0.04	0.04	0.01	0.01	0.01	0.01	na
Chromium	0.004	0.04	0.001	0.002	0.001	0.001	na
Iron	0.19	0.29	0.08	0.09	0.01	0.09	0.15
Manganese	0.01	0.12	0.002	0.002	0.002	0.002	0.001
Magnesium	0.03	0.02	0.01	0.01	0.01	0.01	na
Lead	0.02	0.06	0.002	0.004	0.003	0.004	0.004
Sodium	0.07	0.2	0.06	0.07	0.05	0.05	na
Potasium	0.08	0.05	0.04	0.03	0.07	0.03	0.0003
Nickel	0.002	0.002	0	0.001	0.0003	0.0002	na
Silicon	0.22	0.13	0.13	0.12	0.12	0.13	0.44
Titanium	0.01	0.01	0.01	0.01	0.01	0.01	0.01
Zinc	0.11	0.39	0.01	0.01	0.01	0.01	0.01

Exhibit 15: Species Analysis

High time-resolution (5-minute average) measurements made at NBHM show that fine PM mass correlates more with SO2 than with CO, NO, or NOy, providing evidence for a strong influence of an industrial origin of some fine PM there. Principal component analysis (PCA) of 5-minute time resolution measurements at NBHM shows an association among CO, NO, and NOy, and a second association between fine PM mass concentration and SO2. To varying degrees, stationary sources emit CO, NO, and SO2; vehicles also emit CO and NO, but their SO2 emissions are much lower than those associated with coal combustion. This result appears to link PM mass concentrations more closely with local industrial sources than with transportation sources.

Monitoring results indicate that a larger region, including more rural portions of Jefferson County and surrounding portions of the state, has annual-average PM_2.5 concentrations of 12 to 14 ug/m³, approaching the ambient air quality standard of 15 ug/m³ annual average. Superimposed on these high regional levels is a diffuse urban concentration increment of approximately 2 ug/m³. In the case of NBHM, an additional highly localized increment of 3 to 4 ug/m³ is also present. The degree to which transportation sources affect the NBHM monitor is not known quantitatively, and cannot be differentiated from other sources influencing the sites based on inspection of PM composition data.

There is some evidence from carbon speciation studies and from receptor modeling of the NBHM data that on average, the contribution of Organic Carbon to PM_2.5 is about 2 to 11 percent from diesel truck exhaust, and 2 to 22 percent from gasoline exhaust, based on a few measurements made in the fall of 2003 and winter of 2004 (e.g. Zheng et al., 2005; Liu et al. 2004, 2006a). This would include both on-road and off-road sources. The continued expansion of Ultra Low Sulfur Diesel (ULSD) fuel into off road and locomotive applications will further aid in the reduction of the localized sources. It was recognized in the study that on site and off road trucks and diesel locomotives are identified as a component of the mobile sources.

With the prevailing winds in the area from the northeast, the North Birmingham monitor appears to be influenced by a valley effect and industrial emissions from facilities located within the highly industrialized Opossum valley. These localized emissions grouped with an already high background concentration of 12 to 14 ug/m³ have resulted in the exceedances observed in the North Birmingham area. During the study period, the remaining monitors located in the nonattainment area surround this industrialized area and have recorded values below the annual standard, indicating a highly localized influence of primary PM_2.5 emissions.

VISTAS and ASIP modeling indicates that the Clean Air Interstate Rule along with national mobile source controls will result in about a 1 ug/m³ reduction in the background concentration in the Birmingham area by 2010. The Jefferson County Department of Health and ADEM are also developing a State Implementation Plan to bring the area into attainment beginning in 2010, prior to the open to traffic date of 2012.

F. Year or Years of Peak Emissions Requirements

The transportation conformity rule requires that a project not cause a "hot-spot" over the life of the transportation plan. This criterion is satisfied for FHWA/FTA projects in CO, PM10 and PM2.5 nonattainment and maintenance areas if it is demonstrated that during the time frame of the transportation plan (or regional emissions analysis) no new local violations will be created and the severity or number of existing violations will not be increased as a result of the project. This requirement is established in CFR 40, Part 93.116.

The meaning of these terms is established in 40 CFR, Part 93.101, and that section defines when a new or worsened air quality violation is determined to occur: It states that to "Cause or contribute to a new violation" for a project means:

1. To cause or contribute to a new violation of a standard in the area substantially affected by the project or over a region which would otherwise not be in violation of the standard during the future period in question, if the project were not implemented; or
   
2. To contribute to a new violation in a manner that would increase the frequency or severity of a new violation of a standard in such area."
   

40 CFR 93.101 further defines the phase "Increase the frequency of severity" to mean it would cause a location or region to exceed a standard more often or to cause a violation at a greater concentration than previously existed and/or would otherwise exist during the future period in question, if the project were not implemented."

40 CFR 93.101 further defines a hot-spot analysis as an estimation of likely future localized PM_2.5 or PM₁₀ pollutant concentrations and a comparison of those concentrations to the relevant air quality standards. A hot-spot analysis assesses the air quality impacts on a scale smaller than an entire nonattainment or maintenance area, including for example, congested roadway intersections and highways or transit terminals. Such analysis is a means of demonstrating that a transportation project meets Clean Air Act conformity requirements to support state and local air quality goals with respect to potential localized air quality impacts. When a hot-spot analysis is required, it is included within the project-level conformity determination that is made by FHWA or the Federal Transit Administration (FTA).

As clarified in the preamble to the July 1, 2004, revision to the transportation conformity rule (64 FR 40056), the conformity rule requires that project-level analyses consider the year or years of expected peak emissions from the project. Year of peak emissions is the year in which project emissions, in addition to background regional emissions in the project area, are expected to be the highest. As discussed in the July 1, 2004, final conformity rule (69 FR 40056-40058), hot-spot analyses in metropolitan nonattainment and maintenance areas must consider the full time frame of an area's transportation plan at the time the analysis is conducted.

EPA believes that conformity requirements are met if areas demonstrate that no new or worsened violations occur in the year(s) of highest expected emissions. This condition includes the project's emissions in addition to background regional emissions. If such a demonstration occurs, then no adverse impacts would be expected to occur in any other years within the time frame of the transportation plan or regional emissions analysis.⁸

G. Year or Years of Peak Emissions Determination

In a review of the study "Particulate Matter Sources in Birmingham, Alabama," it is noted that there are localized sources contributing to the violations at the NBHM monitor site. The study indicates that the Birmingham area resides in a larger region having high annual-average PM_2.5 concentrations of 12 to 14 ug/m³, which approaches the ambient air quality standard of 15 ug/m³ annual average PM_2.5 concentrations. The study links PM mass concentrations more closely with local industrial sources than with transportation sources. The study also identifies off road vehicles and locomotives as a contributing source to the monitor violations. This information corresponds to the information made available by EPA titled "1999 National Emissions by Source: Fine Particulate Matter (PM_2.5)." Exhibit 16, PM_2.5 Emissions by Source, below shows that nationally, on road mobile sources account for only 10% contribution to PM_2.5 emissions and off road mobile sources contribute 18% to PM_2.5 emissions.

Exhibit 16: PM _2.5 Emissions by Source

In determining the year of peak emissions there were several factors to consider in establishing a year or years of peak emissions.

Since June 1, 2006, 80% of on-road diesel fuel has been required to be "ultra-low-sulfur diesel" (ULSD), that is a fuel with only 15ppm of sulfur compared to the current standard of 500ppm. Retail outlets were required to comply with this rule by October 15, 2006. The purpose of the new regulation is to make diesel fuel compatible with the new 2007 diesel engine requirements that become effective January 1, 2007. When operated with ULSD, the new engines will produce 90% fewer PM emissions than current diesel engines. Even tougher engine standards come into force starting in 2010 when all retail outlets will carry ULSD fuel for on road highway use. All of these actions take place prior to the project's open-to-traffic year of 2012, but because fleet turnover to cleaner vehicles will occur over many years, 2012 was considered as the possible year of peak emissions.

Non-road mobile sources (18% of the equation) will not be fully required to use ULSD until 2015, since they contribute to the background emissions and the ULSD requirements will not be fully implemented until December 1, 2014. That this reduction to a contributing source of the background emissions occurs 2 years after the opening year of 2012 was a reason to consider 2014 as a possible year of peak emissions.

Exhibit 5, Summary, in Section 6, shows the trend in PM _2.5 over the life of the 2030 Long Range Transportation Plan is shown. The level of PM_2.5 drops by 29% through 2009 and drops an additional 13% by 2015 for a total reduction of 42% and stays below the base year 2002 emissions. Section 6, Exhibit 5, Summary; shows an increase in total PM after 2015. The 2015 transportation modeling year is the first conformity analysis year to include this project. The modeling shows an increase in regional VMT, but it also shows that the PM emissions will continue to stay below the base year 2002 emissions. This was a reason to include 2015 as a possible year of peak emissions.

And ultimately because traffic volumes and VMT increase throughout the range of the Long Range Transportation Plan it would be reasonable to consider the final year of the plan, 2030 as a possible year of peak emissions.

Therefore, 2012, 2014, and 2030 are all reasonable years to consider as a peak year of emissions. And, emissions in each of these years were considered qualitatively for this analysis. Each of the years chosen had a distinct characteristic that marked it for consideration. The years selected represented the open to traffic year (2012), a year in which ULSD regulations for contributing non road mobile sources will be fully implemented (2014) and finally the final year of the Long Range Transportation Plan for the area (2030).

H. Monitor Comparisons

Fine PM samplers (daily and hourly) are located at eight sites in Jefferson County: Pinson, North Birmingham, Corner, Providence, Wylam, McAdory, Hoover, and Leeds. Daily data are available from 2000 through 2004, while hourly measurements begin in late 2001 and continue through 2004. The Leeds monitor did not begin reporting hourly data until 2004. Two locations (North Birmingham and Wylam) have both hourly PM_2.5 and hourly PM10 samplers. In making a comparison of the contribution of transportation sources an examination of the location and characteristics these sites is warranted.

The North Birmingham monitor is located at 3009 28th Street N, at the corner of 30th Avenue, on an undeveloped lot in a mixed commercial-residential-industrial area (Hansen et al., 2003). It is ~0.3 and 1.4 km east of US-31 and I-65, respectively, and ~3.6 km north-northeast of the interchange of I-65 and I-59/20. A cast iron pipe facility is located ~400 m east and several large coking ovens are situated ~2 km northeast and 5-10 km southwest. Additional point sources are located to the southeast and rail lines lie 0.2 to 0.5 km east, southeast, and south of the site. The Wylam monitor is located in a residential neighborhood at 1242 Jersey Street. I-59/20 and a major rail line are ~0.9 km to the southeast, each running approximately southwest to northeast. Another rail line lies ~0.3 km to the northwest. A large steel manufacturing facility is located ~1 km to the southwest. Smaller industrial facilities are located along Commerce Avenue, between I-65 and the adjacent railroad line. The sites at McAdory (Route 8), Providence (1801 Bruce Shaw Road), and Pinson (Pinson High School, Box 360, Highway 75 N) are classified by EPA as rural sites. Leeds (201 Ashville Road) and Hoover (3425 Tamassee Lane) are considered suburban locations. Corner (10005 Corner School Road) is classified as urban and center city (Warrior, population 3,038).

Inasmuch as this is a comparison of site characteristics in relation to transportation the comparison will focus on the transportation characteristics. The discussion will include observed traffic volumes from the years 2003 and 2004 the latest years of monitoring data included in the study "Particulate Matter Sources in Birmingham, Alabama".

Exhibit 17, Average annual PM_2.5 Concentrations, displays the values at the permanent monitoring sites throughout the area. Site location information is shown in Exhibit 18: Site Locations, and the distances between sites are shown in Exhibit 19, Distance between Sites in Kilometers.

Site	1999	2000	2001	2002	2003	2004
NBHM	23.4	22.3	19.1	17.5	17.4	17.7
Wylam	21.3	20.7	17.9	16.6	15.6	15.9
CMZ	22.4	21.5	18.5	17.0	16.5	16.8
McAdory	18.4	16.9	15.0	15.0	14.1	14.6
Providence		16.7	13.3	12.3	12.2	12.4
Leeds						14.7
Hoover	18.7	18.5	15.6	14.4	14.1	14.4
Pinson	19.1	16.5	14.3	13.4	13.5	13.5
Corner		16.8	14.7	13.3	13.5	13.7

Exhibit 17: Average Annual PM 2.5 Concentrations⁹

Site	AIRS	Monitor	Address	UTME	UTMN
N Birmingham	010730023	PM2.5	No. B'Ham,Sou R.R., 3009 28th St. No.	517.1756	3712.42
McAdory	010731005	PM2.5	Route 8 McAdory	499.6639	3687.797
Providence	010731009	PM2.5	1801 Bruce Shaw Road	471.6014	3702.098
Leeds	010731010	PM2.5	201 Ashville Road	541.8596	3711.633
Wylam	010732003	PM2.5	1242 Jersey St Wylam	507.0447	3706.494
Hoover	010732006	PM2.5	3425 Tamassee Lane, Hoover	517.0535	3693.941
Pinson	010735002	PM2.5	Pinson, High Sch., Box 360 Hwy 75 North	530.6611	3729.269
Corner	010735003	PM2.5	10005 Corner School Road	505.323	3739.971

Exhibit 18: Site Locations¹⁰

Site	NBHM	McAdory	Providence	Leeds	WYL	Hoover	Pinson	Corner
N Birmingham	0.0	30.2	46.7	24.7	11.7	18.5	21.6	30.0
McAdory	30.2	0.0	31.5	48.5	20.1	18.4	51.8	52.5
Providence	46.7	31.5	0.0	70.9	35.7	46.2	65.0	50.7
Leeds	24.7	48.5	70.9	0.0	35.2	30.5	20.9	46.2
Wylam	11.7	20.1	35.7	35.2	0.0	16.1	32.8	33.5
Hoover	18.5	18.4	46.2	30.5	16.1	0.0	37.9	47.5
Pinson	21.6	51.8	65.0	20.9	32.8	37.9	0.0	27.5
Corner	30.0	52.5	50.7	46.2	33.5	47.5	27.5	0.0

Exhibit 19: Distance between Sites in Kilometers

North Birmingham Site

This NAMS neighborhood scale site (located in North Birmingham) is located in a valley that is heavily industrialized. This site yields the county's highest reported particulate

Exhibit 20: North Birmingham Monitoring Site

levels. JCDH is presently monitoring for PM_2.5, with a daily manual measurement and continuous methods. The Department also measures PM_2.5 speciation, PM10 and ozone at this site. Traffic counts in this area 81,000 to 83,000 AADT ranges with a growth rate of 3% and a truck percentage of 16%. This site had a three year average annual concentration measurement in 2004 that did exceed the standards.

Wylam Site

Exhibit 21: Wylam Monitoring Site

This NAMS neighborhood scale site (located in Wylam) has been in operation for more than ten years. It is also located at the opposite end of the same valley as the North Birmingham Site. This valley has many metal smelting facilities and is heavily industrialized. This site yields the county's second highest reported particulate matter levels. JCDH is presently monitoring for PM2.5, PM2.5 speciation, and PM10. It is also a collocated site. Traffic counts in this are 85,000 AADT range with a growth rate of 1.05% and a truck percentage of 8%. This site had a three year annual design value ending in 2004 that exceeded the NAAQS standards.

Hoover Site

This SLAMS neighborhood scale population-oriented site (located in Hoover down wind of the Birmingham central business district) was established in the spring of 1985 to monitor levels of ozone in this area of the county. Sampling for PM2.5 started on January 1, 1999. It is located in a residential area. As mentioned previously, JCDH is presently monitoring for PM2.5 and ozone at the site. It is a collocated site for manual PM2.5. Traffic counts in this are 92,000 to 103,000 AADT ranges with a growth rate of 4.56% and a truck percentage of 8%. This site had a three year annual design value ending in 2004 that did not exceed the NAAQS standards even under the influence of these high traffic counts.

Exhibit 22: Hoover Monitoring Site

Mc Adory Site

This SLAMS neighborhood scale population-oriented site is in a rural residential setting and is located in the very wide and expansive Jones Valley and also lies downwind of Birmingham. It is near the route interchange of I-459 and I-59/20. Traffic counts in this are 59,000 AADT ranges with a growth rate of 2.91% and a truck percentage of 18%. This site had a three year annual design value ending in 2004 that did not exceed the NAAQS standards even with this high percentage of truck traffic.

Exhibit 23: McAdory Monitoring Site

Leeds Site

This SLAMS neighborhood scale population-oriented site (located in Leeds) lies in the valley also running northeast to southwest at the eastern side of Jefferson County. Traffic counts in this are 38,000 to 41,000 AADT ranges with a growth rate of 2.75% and a truck percentage of 16%. This site had a three year annual design value ending

Exhibit 24: Leeds Monitoring Site

in 2004 that did not exceed the NAAQS standards with this high percentage of truck traffic.

Pinson Site

This site is in an expanding suburban on the northeast section of Jefferson County within the Pinson Valley. There is little industrial activity in the area. Traffic counts and growth factors are low. Although this site was not selected for comparison, it is identified for informational purposes.

Exhibit 25: Pinson Monitoring Site

Providence Site

This urban scale general background site (located in the western-most corner of Jefferson County) was established in the fall of 1999 to monitor background levels of ozone and PM_2.5 in the county, to get a better idea of what concentrations were entering the county, and to give better resolution at that time for the ozone mapping program. Sampling for PM_2.5 started on January 1, 2000 and monitoring for ozone started on March 1 of that year. It is a rural site in that there are not many residences in the area and most of the land use is agricultural. It is located on a rural mountaintop on the edge of a field used for cattle grazing. It is an excellent site for a background monitor. As mentioned previously, JCDH is presently monitoring for PM_2.5, PM_2.5 speciation and ozone at the site. It is a collocated site for manual PM_2.5. There are no available traffic counts in the vicinity of this monitor. Although this site was not selected for comparison, it is identified for informational purposes.

Exhibit 26 Providence Monitoring Site

Corner Site

This site is a rural site with scattered residences in the area and most of the land use is agricultural. It is located in a rural area in the north-northwest corner of the county. There are no available traffic counts in the vicinity of this monitor. Although this site was not selected for comparison, it is identified for informational purposes.

Exhibit 27: Corner Monitoring Site

The traffic count information and the violation status of each monitor are included in Exhibit 28, Site AADTs.

	2003 AADT	2004 AADT	10 year Growth Rate	% Trucks	Violation
North Birmingham	81,780	83,660	3.00%	16%	Yes
Mc Adory	38,780	41,690	2.75%	16%	Yes
Providence	NA	NA	NA	NA	No
Leeds	59,650	59,190	2.19%	18%	No
Wylam	85,380	85,380	1.05%	8%	No
Hoover	92,330	103,190	4.56%	8%	No
Pinson	NA	NA	NA	NA	No
Corner	NA	NA	NA	NA	No

Exhibit 28: Site AADTs

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³ 2004 was used because this year is consistent with the existing air quality study, "Particulate Matter Sources in Birmingham, Alabama".
⁴ Since the time of the study 3 monitors have violated the NAAQS. See Appendix A for 2004 to 2006 Concentration values.
⁵ See Appendix A for 2004 to 2006 Design values.
⁶ Charles Blanchard, et al., Particulate Matter Sources in Birmingham, Alabama, Prepared for Alabama Department of Environmental Management and Jefferson County Department of Health, April 2006
⁷ Charles Blanchard, et al., Particulate Matter Sources in Birmingham, Alabama, Prepared for Alabama Department of Environmental Management and Jefferson County Department of Health, April 2006
⁸ Transportation Conformity Guidance for Qualitative Hot-spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas, EPA420-B-06-902; March 2006.
⁹ More detailed information on the PM2.5 site locations is in Appendix B.
¹⁰ More detailed information on the PM2.5 site locations is in Appendix C.