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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS
4-1
CH. 4 PHYSICAL ENVIRONMENT
4.1 NOISE
This section summarizes the traffic noise assessment performed for the project. Details are
documented in the project’s Final Traffic Noise Technical Memorandum for the Gaston East-West
Connector (PBS&J, July 2008), incorporated by reference and available on the NCTA Web site
(www.ncturnpike.org/projects/gaston). The analysis was performed in accordance with Title 23 of
the United States Code of Federal Regulation Part 772 – Procedures for Abatement of Highway
Traffic Noise and Construction Noise (23 CFR 772).
4.1.1 CHARACTERISTICS OF NOISE
Noise is defined as unwanted sound. Truck and automobile noise is usually comprised of noises
from engine exhaust, the drive train, and tire/roadway interaction.
The magnitude of noise is usually described by a common unit of reference called the “decibel”
(dB). The A-weighted decibel scale is used almost exclusively when measuring vehicle noise
because it places an emphasis on the frequency range to which the human ear is most sensitive
(1,000–6,000 Hertz). Sound levels that are measured using the A-weighted decibel scale are
written as dBA.
Examples of typical noise levels include 110 dBA for a car horn at 50
feet of distance, 75 dBA for a blender at 3 feet, 55 dBA for a
conversation at 10 feet, and 45 dBA for background noise conditions
in a rural or suburban area.
The criteria that the Federal Highway Administration (FHWA),
NCTA, and North Carolina Department of Transportation (NCDOT)
use to determine noise impacts are based upon hourly average noise levels. In other words, the
fluctuating sound levels of traffic noise are represented in terms of a steady noise level having the
same energy content.
4.1.2 NOISE ABATEMENT CRITERIA
The FHWA has established Noise Abatement Criteria (NAC)
and procedures to be used in the planning and design of
highways.
The FHWA NAC are presented in Table 4-1. As shown in the
table, the NAC are divided into Activity Categories depending
upon different sensitivities to noise. Most land uses in the Project Study Area are in Activity
Noise Abatement Criteria
The FHWA noise abatement
criteria are found in 23 CFR 772,
Procedures for Abatement of
Highway Traffic Noise and
Construction Noise.
Noise Sources
Background noise levels in a
rural or suburban
environment are typically
about 45 dBA. A car horn
produces about 110 dBA at a
50‐foot distance.
Chapter 4 summarizes the project’s impact on the physical environment. Sections within this chapter evaluate the
project’s impacts with respect to noise, air quality, farmlands, utilities and infrastructure, visual quality, hazardous
materials, and floodplains/floodways.
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Categories B and C, and include residences, churches, recreation areas, and businesses. Crowders
Mountain State Park is considered Activity Category A.
TABLE 4-1: Federal Highway Administration Noise Abatement Criteria
Activity
Category Leq (hour) Description of Activity Category
A 57
(exterior)
Lands on which serenity and quiet are of extraordinary significance and serve an
important public need and where the preservation of those qualities is essential if
the area is to continue to serve its intended purpose.
B 67
(exterior)
Picnic areas, recreation areas, playgrounds, active sports areas, parks, residences,
motels, hotels, schools, churches, libraries, and hospitals.
C 72
(exterior) Developed lands, properties, or activities not included in Categories A and B above.
D – Undeveloped lands.
E 52
(interior)
Residences, motels, hotels, public meeting rooms, schools, churches, libraries,
hospitals, and auditoriums.
Source: 23 CFR Part 772
Noise mitigation measures must be considered when future noise levels either approach or exceed the
NAC levels, or if there are substantial increases over existing noise levels. The definitions of
approach and substantial increase are left up to each state. NCDOT defines approach as within
1 decibel of the NAC. NCDOT definitions for “substantial increases” are presented in Table 4-2. The
NCTA follows NCDOT policies, guidance, and procedures regarding noise.
TABLE 4-2: NCDOT Definition of Substantial Increase in
Noise Levels
Existing Average Noise Level
dBA Leq(hour)
Increase (in decibels) from Existing
Noise Levels to Future Noise Levels
Defined as a Substantial Increase
≥55 10 or more
54 11 or more
53 12 or more
52 13 or more
51 14 or more
≤50 15 or more
Source: Traffic Noise Abatement Policy (NCDOT, 2004).
Title 23 CFR Section 772.11(a) states, “In determining and abating traffic noise impacts, primary
consideration is to be given to exterior areas. Abatement will usually be necessary only where
frequent human use occurs and a lowered noise level would be of benefit.”
4.1.3 EXISTING NOISE ENVIRONMENT
Noise levels measurements were conducted within the vicinity of the Detailed Study Alternatives
(DSAs) to determine the typical existing background (i.e., ambient) noise levels and to provide a
basis for assessing the impacts of future traffic noise levels. A sound-level meter was used to
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measure existing traffic and background noise at 22 representative locations on October 16, 17,
29, and 30, 2007.
The measurement locations are shown in Figure 4-1a–b. They include seven measurements
adjacent to area roadways and fifteen locations in areas away from direct traffic noise sources.
Noise measurement sites were selected to represent noise-sensitive land uses in communities
within the vicinity of the DSAs.
At locations where traffic noise did not dominate the noise environment, the existing noise levels
ranged from 39 dBA Leq to 56 dBA Leq. In the seven locations near roadways, noise levels
ranged from 51 dBA Leq to 67 dBA Leq. The existing noise levels measured at each location are
provided in Appendix G (Table G-1).
The majority of receptors adjacent to the DSAs are located in areas away from existing major noise
sources, and were estimated to have existing noise levels of approximately 45 dBA Leq.
4.1.4 NOISE IMPACT ANALYSIS METHODOLOGY
The FHWA Traffic Noise Model® (TNM), Version 2.5, was used to predict future toll-scenario
traffic noise levels for this project. TNM calculates noise levels at modeled locations using inputs
including projected year 2030 peak-hour traffic volumes; vehicle mix (percentages of cars,
medium trucks, and heavy trucks); speed; roadway lengths and gradients; distances between
sources, barriers, and receptors; and shielding provided by intervening terrain, barriers, and
structures.
This analysis used a two-step approach to estimate noise levels. The first step used TNM to develop
noise contours and to identify the sensitive receptors (e.g., houses, schools, churches, parks, etc.)
potentially impacted by traffic noise from the proposed DSAs. The noise contours do not account
for shielding provided by intervening terrain, barriers, or structures. The noise contours are a
conservative estimate of noise levels used for preliminary identification of receptors potentially
impacted by future traffic noise.
In the second step, TNM was used to perform more detailed analyses in areas where
approximately three or more receptors were identified as being potentially impacted based upon
the results of the first step. In these areas, called Neighborhood Study Areas, noise barriers were
evaluated where the detailed model showed impacts receptors (Section 4.1.6.4).
4.1.5 TRAFFIC NOISE IMPACTS
4.1.5.1 Noise Contours
In the first step of the analysis process, TNM was used to develop a conservative estimate of year
2030 noise contours along the mainlines of the DSAs. The 2030 contours provided the basis for a
preliminary identification of potentially affected receptors. Table 4-3 shows the maximum
extent of the 72 dBA Leq and 67 dBA Leq 2030 traffic noise contours for the various segments of
the DSAs. The 67 dBA Leq and 72 dBA Leq contours correspond to the NAC for Activity
Categories B and C, respectively. Distances to these 2030 contour lines are measured from the
Gaston East-West Connector centerline. The noise contours are based upon the highest projected
2030 toll traffic volumes for each segment for each DSA. This information should assist local
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authorities in exercising land use control over the remaining undeveloped lands adjacent to the
roadway within the local jurisdiction.
As shown in Table 4-3, traffic noise increases from west to east, since traffic volumes are highest
at the eastern end of the project and lowest at the western end. Maps are included in
Appendix G showing the highest 2030 noise contours for each Corridor Segment and the receptors
within the contours.
TABLE 4-3: 2030 Noise Contours
Maximum Contour
Distances
(ft. from Centerline) Mainline Segment
72 dBA Leq 67 dBA Leq
Applicable Detailed Study
Alternatives
100 204 4, 5, 9, 22, 23, 27
95 190 58, 64, 68 I‐85 to US 29‐74
100 200 76, 77, 81
135 260 4, 5, 9, 22, 23, 27
95 190 58, 64, 68 US 29‐74 to Linwood Road
125 250 76, 77, 81
115 235 4, 5, 9, 22, 23, 27 Linwood Road to US 321 125 250 76, 77, 81
Linwood Road to Lewis Road 95 190 58, 64, 68
Lewis Road to US 321 130 250 58, 64, 68
135 260 4, 5, 9, 22, 23, 27, 58
130 250 64, 68 US 321 to Robinson Road
140 265 76, 77, 81
175 305 4, 22, 58, 76
170 300 5, 9, 23, 27, 77, 81 Robinson Road to Bud Wilson Road
165 300 64, 68
175 305 4, 22, 58, 76
170 300 5, 9, 23, 27, 77, 81 Bud Wilson Road to NC 274 (Union
Road)
165 300 64, 68
175 305 4, 22, 58, 76 NC 274 to NC 279 (S New Hope Road) 185 315 5, 9, 23, 27, 64, 68, 77, 81
205 335 4, 5, 9, 22, 23, 27, 58, 68, 76, 77, 81 NC 279 to NC 273 (Southpoint Road) 210 340 64
250 375 4, 9, 22, 27, 58, 68, 76, 81
250 380 23, 77, 5 NC 273 to Dixie River Road
250 385 64
250 375 4, 9, 22, 27, 58, 68, 76, 81 Dixie River Road to I‐485 240 365 5, 23, 64, 77
185 315 4, 9, 22, 27, 58, 68, 76, 81
185 320 5, 23, 77 East of I‐485
190 320 64
Source: Traffic Noise Technical Memorandum for the Gaston East‐West Connector (PBS&J, July 2008).
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Table 4-4 lists the numbers of receptors in each Activity Category predicted to be impacted by
noise, based upon the 2030 traffic noise contours. Impacted receptors are receptors expected to
experience traffic noise impacts either by approaching or exceeding the FHWA NAC based upon
the 72 dBA Leq (for Category C) and 67 dBA Leq (for Category B) traffic noise contours, or by a
substantial increase in exterior noise levels. The numbers of impacted receptors range from 196
impacted Category B receptors for DSA 68, to 301 impacted Category B receptors for DSA 76.
Category B receptors in the vicinity of the DSAs include residences and churches. Relatively few
businesses (Category C) would be impacted by noise along the DSAs, with the numbers of impacts
ranging from three businesses for DSA 77 to ten businesses for DSA 22. The impacts to Category B
receptors are primarily substantial increase impacts. The area is rural and suburban, with relatively
few major roadways.
TABLE 4-4: Impacted Receptors by Detailed Study
Alternative Based on 2030 Traffic Noise
Contours
Number of Impacted Receptors Detailed Study
Alternative Category B1 Category C2 Total
4 293 9 302
5 267 4 271
9 237 8 245
22 288 10 298
23 262 5 267
27 232 9 241
58 263 9 272
64 226 5 231
68 196 8 204
76 301 8 309
77 275 3 278
81 269 7 276
Source: Final Traffic Noise Technical Memorandum for the Gaston East‐West
Connector (PBS&J, July 2008).
Notes: 1. Category B receptors include residences and churches.
2. Category C receptors include businesses.
4.1.5.2 Potential Noise Impacts to Churches, Schools, and Other
Special Uses
Churches. Six churches are located within the year 2030 67 dBA Leq traffic noise contours. These
are, from west to east: Broomfield Methodist Church, Pisgah ARP Church, True Vine Church of God,
Open Door Ministries, Gaston Christian Church, and Grace Wesleyan Church. Potential noise
impacts to these churches are discussed below.
Broomfield Methodist Church. This church is located adjacent to Corridor Segment H2A (DSAs 4, 5,
9, 22, 23, and 27) at 909 Shannon Bradley Road. A barrier for this church and adjacent residences
was found to be feasible and reasonable (Barrier 1-1) (Section 4.1.6.4). With the barrier in place,
the church would not be impacted by noise.
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Pisgah ARP Church. This church is located adjacent to Corridor Segment H2B (DSAs 22, 23,
and 27) at 3600 Linwood Road. The 66 dBA Leq noise contour passes through a wooded area on
the church property that is not a frequent outdoor-use area. The area near the church structures
and small yard is projected to average about 62–63 dBA Leq in the peak hour based upon the
noise contour files. This represents a substantial increase above the estimated existing noise
level of 45 dBA Leq, but does not exceed the outdoor use NAC for Category B. It should be noted
that in this area, the Gaston East-West Connector mainline is below grade (i.e., depressed below
surrounding ground) and noise levels likely would be less than those predicted with the noise
contour model. Therefore, a noise impact is not anticipated.
The interior standard of 52 dBA Leq would not be exceeded at the church structures. The
structures are masonry, which can achieve 25–35 dBA of exterior to interior noise reduction
(Highway Traffic Noise Analysis and Abatement: Policy and Guidance, FHWA, June 1995). If
the structures were assumed to achieve 25 dBA of exterior to interior noise reduction, and the
future outside noise level was 63 dBA Leq, then the interior noise levels would be 38 dBA Leq,
which is below the interior NAC.
True Vine Church of God. This church is located adjacent to Corridor Segment H1C (DSAs 58, 64,
and 68) at 5348 Lewis Road. The church structures likely would be within the right-of-way limits of
the proposed project and would need to be relocated if DSA 58, 64, or 68 is selected as the Preferred
Alternative. Based upon aerial photographs, the parcel does not appear to have an area of frequent
outdoor use. If the church structures are relocated to another area of the remaining property farther
from the project, interior noise levels would not exceed the interior NAC of 52 DBA Leq. At least 20
dBA of exterior to interior noise reduction can be achieved by light frame buildings (Highway Traffic
Noise Analysis and Abatement: Policy and Guidance, FHWA, June 1995), and the remainder of
the parcel would experience noise levels of 66 dBA Leq or less.
Open Door Ministries. This church is located south of Corridor Segment J5B (DSAs 4, 22, 58, and 76)
at 783 Union New Hope Road. The 60 dBA Leq noise contour line passes through the northern
portion of the parcel that is wooded and undeveloped and is not an area of frequent outdoor use.
Therefore, there would be no project-generated traffic noise impacts to this church.
Gaston Christian Church. This church is located south of Corridor Segment K2A (DSAs 4, 22, 58,
and 76) at 5339 South New Hope Road (NC 279). The main church building is located on the south
side of the parcel and the structure and its surrounding area would not be impacted by project-
generated noise.
Grace Wesleyan Church. This church is located north of Corridor Segment K1C (DSAs 5, 23, 64, and
77) at 6014 South New Hope Road. The 60 dBA Leq contour line passes through the southern end of
the church property in a wooded, undeveloped area where there is no frequent outdoor use. The
church would not be impacted by project-generated noise.
Schools and Libraries. There are two schools and a library within the vicinity of the DSAs.
Sadler Elementary is located at 3940 West Franklin Boulevard (US 29-74) on the east side of
Corridor Segment H1A (DSAs 58, 64, 68, 76, 77, and 81). Forestview High School is located at
5545 Union Road north of Corridor Segment J5a (DSAs 4, 22, 58, and 76). The Union Road
Branch Library is located across existing Union Road and slightly to the south of Forestview
High School. None of the projected noise contours would be on school or library property and
there would be no noise impacts from any of the DSAs.
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Parks and Recreation Areas. This section discusses potential noise impacts to Crowders
Mountain State Park, Linwood Springs Golf Course (a privately-owned golf course open to the
public), Duke Energy recreational fields (privately-owned by Duke Energy Corporation), and
Berewick District Park (a proposed Mecklenburg County Park). Daniel Stowe Botanical Garden and
the Park at Forestview High School were located too far from the proposed DSAs to be potentially
impacted by traffic noise.
Crowders Mountain State Park. Crowders Mountain State Park is located to the west of the DSAs.
Crowders Mountain State Park is a natural forest park offering activities such as hiking and
climbing. The park is considered a Category A land use. Category A lands are “lands on which
serenity and quiet are of extraordinary significance and serve an important public need and
where the preservation of those qualities is essential if the area is to continue to serve its
intended purpose.” (23 CFR Part 772). Category A lands have a NAC of 57 dBA Leq. As
discussed below, no noise impacts to the park are projected to occur.
For comparison purposes, the existing noise levels in the park were assumed to be about 39–
40 dBA Leq, which are the lowest noise levels measured within the Project Study Area
(Appendix G – Table G-1). NCDOT standard practice is to assume 45 dBA Leq for the natural
environment, so assuming a lower value is conservative.
The noise contours developed for Corridor Segments H1A and H1B (DSAs 58, 64, 68, 76, 77, and
81), which are closest to the park, were used to estimate the maximum future 2030 project-
related traffic noise levels likely to occur at the nearest park boundary and at the nearest point
along the hiking trails inside the park. The nearest park boundary is approximately 1,500 feet
from the centerline of Corridor Segment H1A. The nearest point on the hiking trails is on the
Tower Trail, which is approximately 2,800 feet from the centerline of Corridor Segment H1A.
Based upon the projected 2030 noise contours, maximum 2030 project-generated traffic noise
levels at the park boundary nearest the DSAs (1,500 feet away) would be approximately
46 dBA Leq, well below the Category A NAC of 57 dBA Leq, and below being classified as a
substantial increase. At the nearest point of the Tower Trail (2,800 feet), maximum 2030 project-
generated traffic noise levels would be approximately 42 dBA Leq, also well below the impact
thresholds. Actual project-generated noise levels likely would be less due to reductions in noise
levels from intervening terrain and vegetation that were not taken into account in developing the
noise contours. Therefore, the park is not anticipated to experience traffic noise impacts due to
this project.
Linwood Springs Golf Course. Linwood Springs Golf Course is located on Linwood Road, just west of
Corridor Segment H3 (DSAs 4, 5, and 9). This golf course is privately-owned, but open for public use.
Since this is an active-use park, it is a Category B use. Neither the 60 dBA Leq nor the 66 dBA Leq
noise contour encroach on the areas of the golf course property used for play. Therefore, no project-
generated noise impacts are expected at this golf course.
Duke Energy Recreational Fields. These two private recreational fields, owned by Duke Energy
Corporation are located northwest of Allen Steam Station on Boat Club Road, just south of
Corridor Segment K3B (DSAs 4, 9, 22, 27, 58, 68, 76, and 81). Since these are active uses, they
fall under Category B.
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Future peak-hour noise levels are projected to average approximately 63 dBA Leq at the baseball
field and 58 dBA Leq at the general recreational field. The baseball field would experience a
substantial increase in noise levels (18 decibels), but neither field would experience noise levels
above the NAC of 66 dBA Leq. A noise barrier was modeled for this area and found not to be cost
effective.
Berewick District Park. Berewick District Park is a proposed Mecklenburg County park located at
the eastern terminus of the project, just south of the DSAs and west of I-485. The 66 dBA Leq noise
contour from Corridor Segment K4A (DSAs 5, 23, 64, and 77) is on the northern edge of the park.
No proposed uses are near the northern edge of the park where the project’s 66 dBA Leq noise
contour for Corridor Segment K4A is located. Project-generated noise would be 60 dBA Leq or
less where the proposed park uses are located. Therefore, the park is not anticipated to
experience project-generated traffic noise impacts.
4.1.5.3 Construction Noise
The major construction elements of this project are expected to be earth removal, hauling,
grading, and paving. General construction noise impacts (such as temporary speech interference
for passersby and those individuals living or working near the project) can be expected,
particularly from paving operations and from earth-moving equipment during grading
operations. Overall, construction noise impacts are expected to be minimal and temporary.
Furthermore, the shielding provided by surrounding wooded areas, hills, structures, and other
natural and man-made features are considered sufficient to moderate the effects of intrusive
construction noise.
4.1.6 NOISE ABATEMENT MEASURES
If traffic noise impacts are predicted, examination and evaluation of alternative noise abatement
measures for reducing or eliminating the noise impacts must be considered. Types of abatement
measures include highway alignment selection, traffic management measures, vegetative buffers,
or noise barriers. As described below, due to design constraints, access and space requirements,
and cost considerations, noise barriers were found to be the only feasible method of abatement.
Highway Alignment. For noise abatement, highway alignment selection involves both the
horizontal and vertical orientation of the proposed improvements. Horizontal alignment selection
is primarily a matter of placing the roadway sufficiently far from noise sensitive areas.
Depressing or raising the highway elevations (vertical alignment) can create cut and fill slopes
which may block the line of sight from a receptor to a road and provide shielding from traffic
noise. No major alterations in the proposed horizontal or vertical alignment of this project for
noise purposes are feasible. The proposed preliminary design alignments fall within the design
criteria for the roadway classification and take into account the existing topography of the area,
interchanges, existing roads, residences, businesses, and cultural and natural resources.
Traffic Management. Traffic management measures that limit vehicle type, speed, volume,
and time of operations can be effective noise-abatement measures. For this project, traffic
management measures are not considered appropriate for noise abatement due to their effect on
the capacity and level of service (LOS) of the proposed roadway.
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Vegetative Buffers. The use of vegetative buffers for noise mitigation is not considered
reasonable for this project, due to the substantial amount of right of way necessary to make
vegetative barriers effective. FHWA research has shown that a vegetative buffer should be
approximately 200 feet wide to provide a 10 dBA reduction in noise levels (Highway Traffic Noise
Abatement, FHWA Web site: www.fhwa.dot.gov/environMent/noise/polguide/abatement.htm).
The cost of the additional right of way, vegetation, and relocations would most likely exceed the
maximum cost threshold considered reasonable in the Traffic Noise Abatement Policy (NCDOT,
2004).
Noise Barriers. Solid barriers reduce noise levels by blocking the sound path between the noise
source and noise-sensitive areas. This measure is most often used on high-speed, limited access
facilities where noise levels are high and there is adequate space for continuous barriers.
For a noise barrier to provide sufficient noise reduction it must be high enough and long enough
to shield the receptor (e.g., house, church, park, school, etc.) from substantial sections of the
roadway. The barrier must also be feasible to construct as well as reasonable. Traffic Noise
Abatement Policy provides guidance on determining the feasibility and reasonableness of
providing noise barriers, as discussed below (NCDOT, 2004).
Feasibility of barrier construction considers potential safety and/or drainage problems, whether a
barrier can be built upon the site topography, and whether other noise sources are present within
the area. Noise reductions of 10 decibels or less are usually attainable, and the barrier should
achieve at least 5 decibels of noise reduction for front-row receptors.
Reasonableness factors include the following: barrier cost, support for the barrier from directly
adjacent receptors, the degree of noise impact, and required noise barrier height. A reasonable
barrier must be cost effective and not more than 25 feet high. The NCDOT and NCTA consider a
cost-effective barrier as one that costs no more than $35,000 per effectively protected site (a site
having 5 decibels or more reduction), plus an incremental increase of $500 per average decibel
increase in the predicted exterior noise levels of the impacted receptors within the area. The cost
of the noise barrier used in these calculations is $15.00 per square foot. Also, in general, noise
barriers are not considered feasible for businesses or isolated residences.
Neighborhood Study Areas for Noise Barriers. The noise-sensitive sites predicted to be
impacted directly (i.e., experience noise levels that approach or exceed FHWA NAC or show a
substantial increase over existing levels) that were not considered isolated sites were further
evaluated in terms of the feasibility and reasonableness of providing noise barriers.
Thirty-four Neighborhood Study Areas were modeled in detail in TNM to determine if barriers
would be feasible and reasonable in these locations. Figure 4-1a–b shows the locations of
Neighborhood Study Areas. The detailed analysis of potential noise barriers within these areas
incorporated existing natural terrain and design features such as fill/cut sections.
As the result of the analyses performed for the 34 areas mentioned above, 22 locations were
identified where preliminary noise barriers were determined to be feasible and reasonable.
These preliminary noise barriers are shown on Figure 4-1a–b and listed in Table 4-5.
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The determination of feasibility and reasonableness
is preliminary and subject to change based upon final
design, building permits issued as of the Date of
Public Knowledge, and the public involvement
process. The majority of receptors directly adjacent
to the barrier (the front-row receptors) must support
the construction of the noise abatement measure
(Traffic Noise Abatement Policy, NCDOT, 2004).
The preliminary feasible and reasonable barriers
reduce noise for single-family residential subdivisions
and mobile home communities. Barrier lengths
range between 600 feet and 2,640 feet, while barrier
heights range between 10 feet and 20 feet. The
approximate costs for the preliminary barriers identified in Table 4-5 are between $90,000 and
$625,200; and costs per benefited receptor are between $13,976 and $44,500.
TABLE 4-5: Preliminary Feasible and Reasonable Noise Barriers
Barrier
Prelim.
Barriers1
Segment
DSA Description
Average
dBA
Reduction
for
Benefited
Receptors
Number
of
Benefited
Receptors
Length
(Ft)
Height
(Ft)2
Cost
Cost Per
Receptor
Allowable
Cost per
Receptor
1‐1
H2A
(4, 5, 9,
22, 23,
27)
North of US 29‐74,
westbound side of
alignment. Brookhaven
and Spring Valley
subdivisions.
9 34 2,640 12 $475,200 $13,976
$40,824
H1A
(64, 58,
68)
10 20 1,400 20 $420,000 $21,000
$42,200
3‐1 H1A
(76, 77,
81)
East of Crowders Mtn,
north of Linwood Rd,
eastbound side of
alignment. Brentwood
Mobile Home Park. 10 20 1,400 20 $420,000 $21,000
$44,500
4‐1 H3
(4, 5, 9)
East of Linwood Springs
Golf Course, at Linwood
Rd, on westbound side of
alignment. Lakewood
Forest subdivision.
9 16 1,605 20 $481,500 $30,094
$41,188
6‐1
H2C
(22, 23,
27)
East of Chapel Grove Rd,
eastbound side of
alignment. Fallscrest
subdivision; includes
Donnabrook Rd and
Fallsdale Dr.
8 7 1,250 12/
14 $252,330 $36,047
$42,714
7‐1 H3
(4, 5, 9)
South of Linwood Rd on
the westbound side of
alignment. Stablegate
Farms subdivision.
8 11 1,500 16 $360,000 $32,727
$41,909
Date of Public Knowledge.
The Date of Public Knowledge of the location of
the proposed project is the approval date of
the Record of Decision (ROD). The
Federal/State government is not responsible
for providing noise‐abatement measures for
new development when building permits are
issued within the noise impact area of a
proposed highway project after the Date of
Public Knowledge. For development occurring
after this date, local governing bodies are
responsible for ensuring that noise‐compatible
designs are utilized along the proposed route.
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TABLE 4-5: Preliminary Feasible and Reasonable Noise Barriers
Barrier
Prelim.
Barriers1
Segment
DSA Description
Average
dBA
Reduction
for
Benefited
Receptors
Number
of
Benefited
Receptors
Length
(Ft)
Height
(Ft)2
Cost
Cost Per
Receptor
Allowable
Cost per
Receptor
8‐1
H1C
(58, 64,
68)
South of Old Church Rd,
the westbound side of
alignment. West Palm
Acres subdivision.
7 15 1,575 16 $378,000 $25,200
$36,500
9‐1
HX2
(76, 77,
81)
South of Jake Long Rd,
westbound side of
alignment. Chapel Grove
Rd subdivision.
11 22 2,145 16 $514,800 $23,400
$41,600
11‐1
H2C
(22, 23,
27)
South of Chapel Grove
Rd, on the eastbound
side of alignment. Forest
Estates subdivision.
7 11 1,610 16/
18 $415,200 $37,745
$41,909
12‐1 J4A
(4, 5, 9)
North of Crowders Creek
Rd north of New Haven
Dr, westbound side of
alignment. Falls Estates
subdivision.
5 4 600 10 $90,000 $22,500
$40,000
12‐2 J4A
(4, 5, 9)
North of Crowders Creek
Rd, south of New Haven
Dr, westbound side of
alignment. Falls Estates
subdivision.
8 6 1,395 12 $251,100 $41,850
$44,000
14‐1
H1C
(58, 64,
68)
South of Bethany Rd,
westbound side of
alignment. Jack A. Shell
Mobile Home Park and
Spring Dr subdivision.
8 13 1,485
14/
16/
18
$371,700 $28,592
$42,615
J4A
(4, 5, 9,
22, 23,
27)
7 8 1,092 12/
14 $224,760 $28,095
$38,188
17‐1
J2A
(76, 77,
81)
East of US321,
westbound side of
alignment. Charleston
subdivision. 6 7 1,092 12/
14 $224,760 $32,109
$38,643
J2C
(4, 5, 9,
22, 23,
27)
8 11 1,558
10/
12/
16/
14
$316,860 $28,805
$38,818
17‐2
J2C
(76, 77,
81)
East of US321,
westbound side of
alignment. Forbes Cove
subdivision.
7 11 1,558
10/
12/
16/
14
$316,860 $28,805
$38,818
17‐3
J2C
(4, 5, 9,
22, 23,
27, 76,
77, 81)
East of US321,
westbound side of
alignment. Wesley Acres
subdivision.
7 16 2,306
12/
14/
12/
10
$393,600 $24,600
$42,125
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TABLE 4-5: Preliminary Feasible and Reasonable Noise Barriers
Barrier
Prelim.
Barriers1
Segment
DSA Description
Average
dBA
Reduction
for
Benefited
Receptors
Number
of
Benefited
Receptors
Length
(Ft)
Height
(Ft)2
Cost
Cost Per
Receptor
Allowable
Cost per
Receptor
17‐4
J2C, JX1
(4, 5, 9,
22, 23,
27, 58,
76, 77,
81)
West of Robinson Rd,
eastbound side of
alignment. Pam Dr
subdivision.
7 16 1,949
10/
12/
14/
12
$368,280 $23,018
$42,969
19‐1 J1C
(64, 68)
East of Robinson Rd, on
westbound side of
alignment. Cedar Grove
subdivision.
7 16 1,300
18/
16/
14
$323,100 $20,194
$38,000
25‐1
K2A, J5B
(4, 22,
58, 76)
North of Union‐New
Hope Rd, eastbound side
of alignment. Rowe St
area.
7 17 2,225
16/
14/
10/
8
$488,280 $28,722
$42,824
28‐1
K4A
(5, 23,
64, 77)
East of South Fork
Catawba River,
eastbound side of
alignment. Forest Bay
subdivision.
8 19 2,400 16 $576,000 $30,316
$44,000
28‐3
K4A (5,
23, 64,
77)
Northwest of
NC273/Gaston
interchange westbound
side of alignment.
Southpoint Landing
subdivision.
7 15 2,175 18 $587,250 $39,150
$41,333
KX1
(4, 22,
58, 76)
7 25 1,980 14 $415,800 $16,632
$42,920
29‐1
K3A
(9, 27,
68, 81)
Northwest of
NC273/Gaston
interchange westbound
side of alignment. Brook
Forest subdivision. 6 20 2,605 16 $625,200 $31,260
$40,600
29‐2
K3C
(4, 9, 22,
27, 58,
68, 76,
81)
Northeast of
NC273/Gaston
interchange westbound
side of alignment.
8 9 1,280 20/
18 $354,300 $39,367
$44,500
33‐1
K3D
(4, 9, 22,
27, 58,
68, 76,
81)
East of Dixie River Rd on
eastbound side of
alignment. Garrison Rd
area.
7 17 2,032
12/
16/
14
$460,590 $27,094
$38,176
Source: Final Traffic Noise Technical Memorandum for the Gaston East‐West Connector (PBS&J, July 2008).
1. The determination of feasibility and reasonableness is preliminary and subject to change based on final design, building permits
issued as of the Date of Public Knowledge, and the public involvement process.
2. Barrier height varies as indicated. For example, “18/16/14” means that barrier has an 18‐ft section, 16‐ft section, and 14‐ft section.
A summary of the preliminary feasible and reasonable barriers included in each DSA is
presented in Table 4-6. In general, DSAs closer to the municipal limits (e.g., DSA 4, 5, 9, 22, 27,
and 76), particularly on the west side of the Project Study Area, have more noise impacts, a
greater number of feasible and reasonable noise barriers, and higher noise-abatement costs. In
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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-13
Criteria Pollutants
The USEPA has established
National Ambient Air Quality
Standards (NAAQS) for six
criteria pollutants:
• Carbon monoxide (CO)
• Nitrogen dioxide (NO2)
• Sulfur dioxide (SO2)
• Ozone (O3)
• Particulate matter
• Lead
order, DSAs 4, 9, and 22 have the longest length of barrier and the highest noise-abatement
costs. DSA 64 has the shortest length of barrier and the lowest noise-abatement costs.
A Design Noise Study will be prepared during final design of the Preferred Alternative. The
Design Noise Study will update the noise analysis based upon updated traffic forecasts and the
final design.
TABLE 4-6: Summary of Noise Barriers by Detailed Study Alternative
DSA
Total Number
of Feasible and
Reasonable
Noise Barriers*
Total Length of Noise
Barriers
(ft)
Total Cost of Noise
Barriers
Total Number of
Benefited
Receptors
4 13 22,162 $4,680,270 191
5 11 19,220 $4,124,550 157
9 12 20,562 $4,401,390 169
22 11 19,922 $4,165,200 171
23 9 16,980 $3,609,480 144
27 10 18,322 $3,886,320 149
58 8 13,926 $3,256,950 132
64 6 10,335 $2,656,050 98
68 7 11,677 $2,932,890 110
76 10 17,967 $3,957,270 161
77 8 15,025 $3,401,550 128
81 9 16,367 $3,678,390 139
Source: Final Traffic Noise Technical Memorandum for the Gaston East‐West Connector (PBS&J, July 2008).
*The determination of feasibility and reasonableness is preliminary and subject to change based upon final
design, building permits issued as of the Date of Public Knowledge, and the public involvement process.
4.2 AIR QUALITY
This section summarizes the air quality assessment performed for the project. Air pollutants
evaluated include those with a National Ambient Air Quality Standard (NAAQS), mobile source
air toxics, and potential air quality impacts from construction activities. Details are documented
in the project’s Final Air Quality Technical Memorandum for the Gaston East-West Connector
(PBS&J, September 2008), incorporated by reference and available on the NCTA Web site
(www.ncturnpike.org/projects/gaston). Also included in this section is an assessment of the
potential for bridge icing at the Catawba River due to water-vapor emissions from the Duke
Energy Allen Steam Station air pollution control equipment. Details of this icing assessment are
documented in Analysis of Potential Icing Impacts Due to Allen
Steam Station SO2 Scrubber – Gaston East-West Connector
(MACTEC, September 2008), incorporated by reference.
4.2.1 NATIONAL AMBIENT AIR QUALITY
STANDARDS
The federal Clean Air Act of 1970, as amended (42 USC 7401),
was enacted for the purposes of protecting and enhancing the
quality of the nation’s air resources to benefit public health,
welfare, and productivity. The US Environmental Protection
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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-14
Agency (USEPA) has established primary and secondary NAAQS for six air pollutants: carbon
monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), particulate matter, and
lead. These six pollutants are commonly known as “criteria pollutants.”
Table 4-7 lists the NAAQS. The primary standards are set at a limit intended to “protect the
public health with an adequate margin of safety,” and the secondary standards are set at a limit
intended to “protect the public welfare from known or anticipated adverse effects (effects to
aesthetics, crops, architecture, etc.)” (Federal Clean Air Act 1990: Section 109, 42 USC 7409). The
primary standards are established with a margin of safety, considering long-term exposures for
the most sensitive groups in the general population (i.e., children, senior citizens, and people with
breathing difficulties).
TABLE 4-7: National Ambient Air Quality Standards
Criteria Pollutant Averaging Time Standard(5) Standard Type
8‐hour Average (1) 9 ppm Primary
Carbon Monoxide
1‐hour Average (1) 35 ppm Primary
Nitrogen Dioxide Annual Arithmetic Mean 0.053 ppm Primary and Secondary
1‐hour Average (8) 0.12 ppm Primary and Secondary
8‐hour Average (1997 Standard) (6) 0.08 ppm Primary and Secondary Ozone
8‐hour Average (2008 standard) (7) 0.075 ppm Primary and Secondary
Quarterly Average 1.5 µg/m3 Primary and Secondary
Lead
Rolling 3‐month Average (4) 0.15 µg/m3 (2) Primary and Secondary
Particulate Matter
<10 micrometers (PM10) 24‐hour Average (3) 150 µg/m3 Primary and Secondary
Annual Arithmetic Mean (4) 15 µg/m3 Primary and Secondary Particulate Matter
<2.5 micrometers
(PM2.5) 24‐hour Average (5) 35 µg/m3 Primary and Secondary
Annual Arithmetic Mean 0.03 ppm Primary
24‐hour Average (1) 0.14 ppm Primary Sulfur Dioxide
3‐hour Average (1) 0.50 ppm Secondary
Source: USEPA Web site: www.epa.gov/air/criteria.html
1. The 1‐hour average only applies to areas participating in an Early Action Compact. The Charlotte (NC)–Gastonia (NC)–Rock Hill
(SC) air quality region is not an Early Action Compact area.
2. Not to be exceeded more than once per year.
3. Final rule signed October 15, 2008.
4. Not to be exceeded more than once per year on average over 3 years.
5. To attain this standard, the 3‐year average of the weighted annual mean PM2.5 concentrations from single or multiple
community‐oriented monitors must not exceed 15.0 µg/m3.
6. To attain this standard, the 3‐year average of the 98th percentile of 24‐hour concentrations at each population‐oriented monitor
within an area must not exceed 35 µg/m3 (effective December 17, 2006).
7. To attain this standard, the 3‐year average of the fourth‐highest daily maximum 8‐hour average ozone concentrations measured
at each monitor within an area over each year must not exceed 0.075 ppm. (effective May 27, 2008)
8. (a) To attain this standard, the 3‐year average of the fourth‐highest daily maximum 8‐hour average ozone concentrations
measured at each monitor within an area over each year must not exceed 0.08 ppm. (b) The 1997 standard—and the
implementation rules for that standard—will remain in place for implementation purposes as USEPA undertakes rulemaking to
address the transition from the 1997 ozone standard to the 2008 ozone standard.
Pollutants that have a NAAQS are called criteria pollutants. An area that exceeds the NAAQS
for one or more criteria pollutants is said to be in “non-attainment” of the NAAQS enforced under
the Clean Air Act. The designation of an area is determined on a pollutant-by-pollutant basis.
The USEPA classifies areas as either in attainment or non-attainment. Non-attainment areas
for ozone, carbon monoxide, and some particulate matter are further classified based upon the
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-15
degree of exceedance(s) over the NAAQS (e.g., marginal, moderate, serious, severe, and extreme).
Attainment areas are categorized as either “in attainment” or as a “maintenance area for
attainment”, which means that the urban area has exceeded NAAQS levels for one or more
pollutants in the past. Efforts in these maintenance areas must be made in order to maintain the
status quo and not exceed the NAAQS. (USEPA Web site: www.epa.gov/oar/oaqps/greenbk).
The following paragraphs include brief descriptions of each of the criteria air pollutants, their
standards, and the attainment status of the project region.
Carbon Monoxide. Carbon monoxide is a colorless, odorless gas resulting from incomplete fuel
combustion from both mobile and stationary sources and is the most commonly occurring air
pollutant. Transportation accounts for the majority of carbon monoxide emissions (2000 Ambient
Air Quality Report, North Carolina Department of Environment and Natural Resources
[NCDENR] Division of Air Quality [NCDAQ], 2002).
Except for Mecklenburg County, all other areas within the Charlotte-Gastonia-Rock Hill air
quality region are designated as attainment for carbon monoxide. Mecklenburg County is a
maintenance area for carbon monoxide (USEPA Web site: www.epa.gov/oar/oaqps/greenbk).
Nitrogen Dioxide. Several gaseous oxides of nitrogen are normally found in the atmosphere.
The Charlotte-Gastonia-Rock Hill air quality region is in attainment for the nitrogen dioxide
NAAQS (USEPA Web site: www.epa.gov/oar/oaqps/greenbk).
Ozone. Ozone (O3) is the main component of smog. Since ozone is formed by chemical
interactions with sunlight, ozone concentrations are generally higher during the daytime and in
late spring through early fall (2000 Ambient Air Quality Report, NCDAQ, 2002).
On April 14, 2006, the Charlotte-Gastonia-Rock Hill air quality region was designated as a
moderate non-attainment area for the 1997 8-hour ozone NAAQS (USEPA Web site:
www.epa.gov/oar/oaqps/greenbk). The region includes the following counties in North Carolina:
Mecklenburg, Gaston, Lincoln, Cabarrus, Rowan, Union, and the southern portion of Iredell. The
urbanized area of eastern York County, South Carolina, also is included.
Lead. Lead (Pb) is a metal found naturally in the environment as well as in manufactured
products. The 1990 Clean Air Act Amendments made the sale, supply, or transport of leaded
gasoline or lead additives unlawful after December 31, 1995. As a result, motor vehicle emissions
of lead declined sharply during the 1980s and early 1990s (Latest Findings on National Air
Quality – Status and Trends through 2006, USEPA, January 2008). The Charlotte-Gastonia-
Rock Hill air quality region is in attainment for the lead NAAQS (USEPA Web site:
www.epa.gov/oar/oaqps/greenbk).
Particulate Matter. Particulate matter is divided into two categories: fine particles (PM2.5),
which are 2.5 micrometers in diameter and smaller, and coarse particles (PM10), which are
smaller than 10 micrometers.
The Charlotte-Gastonia-Rock Hill air quality region is in attainment for all currently applicable
particulate matter NAAQS under the old (1997) standards (USEPA Web site:
www.epa.gov/oar/oaqps/greenbk). North Carolina has recommended, and USEPA has agreed,
that the state is in attainment for the new 2006 PM2.5 NAAQS (2006 24-Hour PM2.5 Standards —
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-16
Region 4 Recommendations and EPA Responses, USEPA Web site:
www.epa.gov/pmdesignations/2006standards/rec/letters).
Sulfur Dioxide. Sulfur oxides contribute to the formation of acid rain and the formation of
particles that reduce visibility (2000 Ambient Air Quality Report, NCDAQ, 2002). The Charlotte-
Gastonia-Rock Hill air quality region is in attainment for the sulfur dioxide NAAQS (USEPA
Web site: www.epa.gov/oar/oaqps/greenbk).
4.2.2 TRANSPORTATION CONFORMITY
Background. Section 176(c) of the Clean Air Act Amendments
(42 USC 7506(c)) requires that transportation plans, programs, and
projects conform to the intent of the State Implementation Plan
(SIP). Conformity requirements apply to transportation plans,
programs, and projects funded or approved by the FHWA or the
Federal Transit Administration (FTA) in areas that do not meet, or
previously have not met, NAAQS for ozone, carbon monoxide,
particulate matter, or nitrogen dioxide (Fact Sheets on Highway Provisions, FHWA Web site:
www.fhwa.dot.gov/safetealu/factsheets/conformity.htm).
In North Carolina, the NCDAQ develops the SIP, which is the document that describes how
North Carolina will maintain or achieve compliance with the NAAQS in non-attainment and
maintenance areas.
USEPA has issued regulations implementing the transportation conformity requirements (40
CFR Part 93). The transportation conformity regulations are intended to ensure that a state
does not undertake federally funded or approved transportation plans, programs, or projects that
are inconsistent with the State’s obligation to meet and maintain the NAAQS.
Under the transportation conformity regulations, a transportation conformity determination is
required every time a Metropolitan Planning Organization (MPO) approves an update or
amendment to its long range transportation plan (LRTP) and transportation improvement
program (TIP). Under federal law, an MPO must “update” its LRTP and TIP at least once every
four years. In addition, an MPO may choose to “amend” the LRTP and TIP more frequently.
Typically, there are multiple amendments within each four-year update cycle. A regional
conformity determination is needed for each update and amendment to an LRTP and TIP.
The regional conformity determination is based on a region-wide analysis of projected emissions
from all existing facilities and projects in the LRTP and TIP.
In addition to the regional conformity determination for LRTPs and TIPs, FHWA also must make
a project-level conformity determination. For all pollutants, a project-level conformity
determination can be made only if the project is included in a conforming LRTP and TIP. In
addition, for carbon monoxide (CO) and particulate matter (PM), a project-level conformity
finding requires a localized conformity analysis, known as a “hot-spot” analysis.
Regional Conformity Analysis. To demonstrate conformity at the regional level, an MPO in a
non-attainment or maintenance area must show that expected emissions from their LRTP and
TIP are within the mobile vehicle emission budgets in the applicable SIP. If there is no approved
SIP, the MPO must apply an “interim emissions test” – which requires, in essence, a finding that
Transportation Conformity
The Clean Air Act
Amendments require that
transportation plans,
programs, and projects
conform to the intent of
the state air quality
implementation plan.
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-17
emissions will be no greater with the proposed improvements in the LRTP/TIP than they would
be without those improvements.
Project-Level (“Hot-Spot”) Conformity Analysis. As noted above, all projects in non-
attainment and maintenance areas must come from a conforming LRTP and TIP. In addition, in
CO and PM non-attainment and maintenance areas, localized (or microscale) analysis may be
necessary to determine project-level transportation conformity for federally funded or approved
highway and transit projects. These projects must come from a currently conforming
transportation plan/program. This type of analysis is sometimes referred to as “hot-spot
analysis” (Transportation Conformity, FHWA Web site:
www.fhwa.dot.gov/environment/conformity/con_broc.htm). For this project, the only hot-spot
analysis required is for CO in Mecklenburg County, since Mecklenburg County is a CO
maintenance area.
Conformity Determinations for LRTPs and TIPs in Metrolina Region. The Gaston East-
West Connector project is located in the Charlotte-Gastonia-Rock Hill air quality region
(Metrolina region). The Metrolina region includes four MPOs: the Gaston Urban Area MPO
(GUAMPO), the Mecklenburg-Union MPO (MUMPO), the Cabarrus-Rowan MPO in North
Carolina, and the Rock Hill-Fort Mill MPO in South Carolina. The Gaston East-West Connector
is located within the boundaries of two MPOs: the GUAMPO and the MUMPO. Therefore, this
section focuses primarily on the conformity status of the GUAMPO and MUMPO areas.
Each of the MPOs in the Metrolina region has its own LRTP and TIP, but air quality emissions
analyses are completed for the region as a whole. Therefore, amendments and updates to the
LRTPs and TIPs are often approved simultaneously (or close in time to one another) based on a
single regional emissions analysis.
For the Gaston East-West Connector project, transportation conformity determinations are
required for two pollutants: ozone and carbon monoxide. The conformity requirements apply
to these pollutants because the Metrolina region as a whole is designated as a nonattainment
area for the 1997 8-hour ozone standard and Mecklenburg County is designated as a
maintenance area for carbon monoxide. See Section 4.2.1 above.
Conformity Determinations for LRTPs. Both GUAMPO and MUMPO currently have
approved LRTPs with a horizon year of 2030. The 2030 LRTPs for the GUAMPO and MUMPO
were adopted on May 24, 2005 and April 20, 2005, respectively. A conformity determination for
these LRTP updates was made on June 8, 2005, and FHWA and FTA issued the conformity
finding (approval of the conformity determination) on June 30, 2005.1 Since that time, there have
been two amendments to the 2030 LRTPs for GUAMPO and MUMPO.
• Amendment 1 is dated September 16, 2005, with a FHWA/FTA conformity finding on
October 1, 2005 for both GUAMPO and MUMPO.
• Amendment 2, the latest conformity determination, is dated May 25, 2007, with a
FHWA/FTA conformity finding on June 29, 2007 for both GUAMPO and MUMPO.
1 The June 8, 2005 conformity determination for the Metrolina Region is titled: Conformity Analysis and
Determination Report for the Cabarrus-Rowan MPO, the Gaston Urban Area MPO, and the Mecklenburg-
Union MPO 2030 Long Range Transportation Plans and the FY 2007–2013 State Transportation
Improvement Programs and for Non-MPO Areas of Lincoln County, Iredell County, Gaston County, and
Union County Areas. A copy of this determination is included in the project file.
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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-18
Both GUAMPO and MUMPO are required to complete updates to their LRTPs within four years
after the most recent update. Therefore, the next update for the GUAMPO LRTP must be
approved by June 30, 2009, and the next update for the MUMPO LRTP must be approved by May
3, 2009. Both MPOs are currently conducting travel demand modeling and air quality analyses
to demonstrate conformity. Because the region does not have an approved SIP, the conformity
analyses for the proposed 2035 GUAMPO LRTP and the 2030 MUMPO LRTP are based on the
“interim emissions test” – which, as noted above, requires a demonstration that emissions with
the proposed improvements will be no greater than emissions without those improvements. The
MPOs are currently exploring a range of options for demonstrating conformity for the LRTPs.
These options include adjusting the mix of new projects included in the LRTPs and alternative
modeling methods to demonstrate conformity.
Conformity Determinations for TIPs. Both GUAMPO and MUMPO currently have approved
TIPs covering the years 2009 through 2015. The 2009–2015 TIPs are direct subsets of their
respective conforming 2030 LRTPs. The FHWA and FTA approved a conformity determination
for the GUAMPO and MUMPO 2009-2015 TIPs on July 11, 2008.2 The current TIPs are valid for
four years. Therefore, updates to GUAMPO’s and MUMPO’s 2009-2015 TIPs are required by
2012.
Potential for “Conformity Lapse Grace Period”. As noted above, MPOs are required to
update LRTPs and TIPs at least once every four years. GUAMPO and MUMPO are currently
working to complete their LRTP updates by the applicable deadlines. The updates can be
completed only if conformity findings are made by those deadlines. If the MPOs are not able to
demonstrate conformity by the applicable deadlines, they will enter a status known as a
“conformity lapse grace period” (CLGP). Specifically, MUMPO would enter a CLGP on May 3,
2009, and GUAMPO would enter a CLGP on June 30, 2009, if the required conformity findings
are not made by those dates. During a CLGP, the MPOs would not be allowed to approve any
amendments to their LRTPs or TIPs. However, their existing 2009-2015 TIPs would remain in
effect during the CLGP. Projects in a conforming TIP are allowed to proceed during the CLGP.
Potential for a “Conformity Lapse”. The CLGP would last for one year. If a CLGP occurs
and an update to the LRTP has not been approved by the end of that year, the region would enter
a status known as a “conformity lapse.” During a conformity lapse, no federal approvals may be
granted and the use of federal funds is halted. The only projects that could proceed during this
period are projects that are exempt from transportation conformity (e.g., road resurfacing, safety
projects, bicycle and pedestrian facilities, etc), transportation control measures that are in an
approved SIP, and project phases that were approved prior to the start of the lapse (for example,
ongoing studies).
Implications for Gaston East-West Connector. Federal and state transportation and
environmental agencies are working collaboratively in an effort to avoid a CLGP and a
conformity lapse. If those events occur, they would not necessarily prevent NCTA from
proceeding with ongoing work in the National Environmental Policy Act (NEPA) process, but
they could delay FHWA’s signing of the ROD. FHWA and NCTA will provide an updated
2 Conformity findings also are required for the so-called “donut area” of Gaston County, which is outside the
MPO boundaries but is included within the ozone nonattainment area. Projects in the Gaston County
donut area are included in NCDOT’s 2009–2015 STIP and also have been found to conform. The USDOT
made a Transportation Conformity Determination on the 2009–2015 STIP on July 11, 2008.
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-19
summary of the region’s conformity status in the Final Environmental Impact Statement (Final
EIS).
Status of State Implementation Plan (SIP) for Metrolina Region. The Clean Air Act
required North Carolina to submit a SIP by June 15, 2007, that describes how the state will
attain the ozone standard by June 15, 2010, which is the statutory deadline for achieving
attainment. The NC DAQ submitted a proposed SIP for the ozone standard to USEPA on
June 15, 2007. On November 17, 2008, USEPA sent a letter to NC DAQ stating that the
proposed SIP did not demonstrate that the ozone standard would be achieved by the June 15,
2010 deadline. Therefore, USEPA recommended that North Carolina seek voluntary
reclassification of its portion of the region from “moderate” to “serious” nonattainment status,
which would extend the attainment deadline. USEPA noted that if North Carolina did not take
this action, USEPA would disapprove the SIP (letter included in Appendix A-8).
On December 19, 2008, NCDAQ sent a letter to USEPA requesting that the previously submitted
SIP be withdrawn and explained that NCDAQ intended to submit an updated SIP by November
2009, demonstrating attainment of the ozone standard by the June 15, 2010 deadline (letter
included in Appendix A-8). The USEPA responded to NCDAQ in a letter dated January 9, 2009
stating that USEPA was making a “finding of failure to submit” a SIP (letter included in
Appendix A-8). This action would be effective when published in the Federal Register.
USEPA’s finding of “failure to submit” a SIP does not trigger any immediate consequences for
this project. However, if NCDAQ does not submit a complete SIP within 24 months from
publication of this finding in the Federal Register, then a penalty known as “highway sanctions”
would apply in accordance with 40 CFR 52.31. Under highway sanctions, federal transportation
funds to the region would be cut off until the required SIP submittal is made. While highway
sanctions are possible, it is unlikely that they would occur. NCDAQ has stated that it intends to
submit a revised SIP in November 2009 for USEPA approval. NCDAQ has also stated that, if the
revised SIP is not approved, the State would seek reclassification of the region to “serious”
nonattainment status, which would extend the attainment deadline and avoid the highway
sanctions. So, even if the revised SIP is not approved, there are actions that the State can take to
avoid highway sanctions.
In conclusion, the Metrolina region continues to face challenges in meeting the complex and
stringent requirements of federal air quality laws. These requirements do not prevent ongoing
studies from continuing, but they have the potential to delay federal approval of transportation
projects in the region. To prevent such delays, federal and state air quality and transportation
agencies are continuing to work together to resolve the air quality issues so that planned
transportation projects can move forward.
4.2.3 MOBILE SOURCE AIR TOXICS
In addition to the criteria air pollutants for which there are NAAQS, USEPA also regulates air
toxics. Most air toxics originate from human-made sources, including on-road mobile sources,
non-road mobile sources (e.g., airplanes), area sources (e.g., dry cleaners) and stationary sources
(e.g., factories or refineries).
Mobile Source Air Toxics (MSATs) are a subset of the 188 air toxics defined by the Clean Air Act.
The MSATs are compounds emitted from highway vehicles and non-road equipment. Some toxic
compounds are present in fuel and are emitted to the air when the fuel evaporates or passes
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through the engine unburned. Other toxics are emitted from the incomplete combustion of fuels
or as secondary combustion products. Metal air toxics also result from engine wear or from
impurities in oil or gasoline.
The USEPA is the lead federal agency for administering the Clean Air Act and has certain
responsibilities regarding the health effects of MSATs. The USEPA issued a Final Rule on
Controlling Emissions of Hazardous Air Pollutants from Mobile Sources (66 CFR 17229) (March
29, 2001). This rule was issued under the authority in Section 202 of the Clean Air Act. In its
rule, USEPA examined the impacts of existing and newly promulgated mobile source control
programs, including its reformulated gasoline (RFG) program, national low emission vehicle
standards, Tier 2 motor vehicle emissions standards and gasoline sulfur control requirements,
and its proposed heavy duty engine and vehicle standards and on-highway diesel fuel sulfur
control requirements. Between 2000 and 2020, FHWA projects that even with a 64 percent
increase in Vehicle Miles Traveled (VMT), these programs will reduce on-highway emissions of
benzene, formaldehyde, 1,3-butadiene, and acetaldehyde by 57 percent to 65 percent, and will
reduce on-highway diesel PM emissions by 87 percent, as shown in Exhibit 4-1.
Exhibit 4-1: Vehicle Miles Traveled vs. Mobile Source Air Toxics Emissions, 2000–
2020
Source: FHWA Web site: www.fhwa.gov/environment/airtoxic/vmtmsat2020.htm
Notes: For on‐road mobile sources. Emissions factors were generated using MOBILE 6.2. MTBE proportion of market for
oxygenates is held constant, at 50 percent. Gasoline RVP and oxygenate content are held constant. VMT: Highway Statistics
2000, Table VM‐2 for 2000, analysis assumes annual growth rate of 2.5 percent. "DPM + DEOG" is based on MOBILE 6.2‐
generated factors for elemental carbon, organic carbon, and SO4 from diesel‐powered vehicles, with the particle size cutoff
set at 10.0 microns. 1 short ton = 907,200,000 mg.
On February 9, 2007, and under authority of CAA Section 202(l), USEPA signed a final rule,
Control of Hazardous Air Pollutants from Mobile Sources, which sets standards to control MSATs
from motor vehicles. Under this rule, USEPA is setting standards on fuel composition, vehicle
exhaust emissions, and evaporative losses from portable containers. The new standards are
estimated to reduce total emissions of MSATs by 330,000 tons in 2030, including 61,000 tons of
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benzene. Concurrently, total emissions of volatile organic compounds will be reduced by over
1.1 million tons in 2030 as a result of adopting these standards.
4.2.4 LOCAL ORDINANCES
Mecklenburg County has an Air Pollution Control Ordinance (MCAPCO). Sections of the
ordinance applicable to transportation sources include:
• Article 1 – Permitting Provisions for Air Pollution Sources, Rules, and Operating
Regulations for Acid Rain Sources, Title V, and Toxic Air Pollutants
o Section 1.5600 – Transportation Facility Procedures
• Article 2 – Air Pollution Control Regulations and Procedures
o Section 2.2000 – Transportation Conformity
o Section 2.0800 – Transportation Facilities
Transportation sources subject to permitting as a transportation facility are defined in the
ordinance as airport facilities (excluding military airfield) and parking facilities.
Section 2.2000 of the ordinance, addressing transportation conformity, states in Subsection
2003(a) that “Conformity analyses, determinations, and redeterminations for transportation
plans, transportation improvement programs, FHWA/FTA projects, and State or local regionally
significant projects shall be made according to the requirements of 40 CFR 93.104 and shall
comply with the applicable requirements of 40 CFR 93.119, 93.120, 93.124, 93.125, and 93.126.”
The MCAPCO also has applicable general provisions for nuisance dust (Section 1.5108) and open
burning (Section 1.5106).
4.2.5 AIR QUALITY IMPACTS
4.2.5.1 Criteria Pollutants and Transportation Conformity
Traffic exhaust is the major point of concern when determining the
air quality impacts of a new roadway facility or the improvement of
an existing roadway facility. Transportation is a primary
contributor to four of the six criteria pollutants: ozone (through
emissions of nitrogen oxides and hydrocarbons), carbon monoxide,
particulate matter, and nitrogen dioxide (Air Quality Planning for
Transportation Officials, FHWA Web site:
www.fhwa.dot.gov/environment/aqplan/index.htm). The impacts
resulting from highway construction can range from intensifying
existing air pollution to improving ambient air conditions.
The criteria pollutants of concern in the Project Study Area are ozone and carbon monoxide, since
the Charlotte-Gastonia-Rock Hill air quality region (which includes Gaston County and
Mecklenburg County) is a moderate non-attainment region for ozone, and Mecklenburg County is
a maintenance area for carbon monoxide.
Since ozone takes several hours to form from hydrocarbons and nitrogen oxide, urban areas as a
whole are regarded as sources of ozone precursors, and ozone emissions are not modeled at the
Pollutants of Concern
Ozone and carbon
monoxide are the criteria
pollutants of concern in the
Project Study Area, which is
part of a moderate non‐
attainment region for
ozone and a maintenance
area for carbon monoxide.
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level of individual streets and highways. Therefore, compliance of an individual project with the
ozone NAAQS is demonstrated if the project is included in a conforming regional transportation
plan, which considers the urban area as a whole.
Carbon monoxide is a more stable atmospheric pollutant (meaning it does not react as quickly
with other chemicals) that is emitted directly from tailpipes. Therefore, localized concentrations
of carbon monoxide can occur, and these can be estimated through modeling. As discussed below,
the compliance of a project with the carbon monoxide NAAQS, therefore, is considered at both the
localized (or hot-spot) level, and at the regional transportation plan level.
Localized Carbon Monoxide Hot-Spot Analysis. In accordance with 40 CFR 93.116, an
FHWA project must not cause or contribute to any new localized carbon monoxide violations, or
increase the frequency or severity of any existing carbon monoxide violations in carbon monoxide
non-attainment and maintenance areas. A quantitative hot-spot analysis is required in the
following cases (40 CFR 93.123):
(i) For projects in or affecting locations, areas, or categories of sites which are identified in
the applicable implementation plan as sites of violation or possible violation.
(ii) For projects affecting intersections that are at Level of Service (LOS) D, E, or F, or those
that will change to LOS D, E, or F because of increased traffic volumes related to the
project.
(iii) For any project affecting one or more of the top three intersections in the non-attainment
or maintenance area with highest traffic volumes, as identified in the applicable
implementation plan.
(iv) For any project affecting one or more of the top three intersections in the non-attainment
or maintenance area with the worst LOS, as identified in the applicable implementation
plan.
The portions of the DSAs in Gaston County do not need to be considered for a carbon monoxide
hot-spot analysis since Gaston County is classified as an attainment area for carbon monoxide.
The applicable implementation plan (i.e., SIP) does not contain a list of locations or intersections
as noted in items i, iii, and iv above. However, there is a list of high-congestion locations in
Mecklenburg County available from the Charlotte Department of Transportation (CDOT) (CDOT
Web site: www.charmeck.org/departments/transportation/roads/home.htm). None of these
intersections are located within the DSAs.
Regarding item ii above, all the DSAs have two interchanges in Mecklenburg County; a freeway-
to-freeway interchange with I-485 and a service interchange with Dixie River Road. The
freeway-to-freeway interchange would have no signalized intersections, and item ii would not
apply. The Dixie River Road interchange locations would have ramp terminal intersections with
Dixie River Road. Based upon the preliminary engineering designs and the 2030 traffic
projections for the project as a toll facility, the ramp terminals at Dixie River Road would operate
at LOS C or better in 2030 (Final Toll Traffic Operations Technical Memorandum, PBS&J,
September 2008), incorporated by reference and available on the NCTA Web site
(www.ncturnpike.org/projects/gaston). In preceding years, traffic volumes are projected to be
less, therefore the LOS is expected to be LOS C or better in those years as well.
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Based upon the discussion above, it is concluded that the project would not cause or contribute to
any new localized carbon monoxide violations or increase the frequency or severity of any existing
carbon monoxide violations since none of the DSAs fit the criteria requiring a quantitative carbon
monoxide hot-spot analysis. This conformity determination meets all of the applicable Clean Air
Act Section 176(c) requirements for federally funded or approved transportation projects.
Specifically, the requirements for CO hot-spot analysis are codified at 40 CFR 93.116 and 3.123.
By meeting these regulatory requirements as well as other requirements in the conformity
regulations, this conformity determination demonstrates compliance with the requirements of
CAA Section 176(c)(1).
Transportation Conformity. The proposed project (STIP Project U-3321) is included in both
the 2030 LRTP for the GUAMPO area and the 2030 LRTP for the MUMPO area, both of which
are conforming transportation plans. In addition, in accordance with 40 CFR 93.115(b)(1), for a
project identified in a transportation plan, the project’s design concept and scope must not have
changed significantly from those described in the transportation plan, or in a manner which
would significantly impact use of the facility.
The DSAs for the project are generally consistent with the project description (freeway) and
project length (about 22 miles—20 miles in Gaston County and 2 miles in Mecklenburg County)
included in both LRTPs, but are not consistent with the assumption that the project is a non-toll
project and the assumption concerning the number of lanes (four). The project currently is being
studied only as a toll facility, and the preliminary engineering designs (January 2008) for the
DSAs show a six-lane facility.
However, it should be noted that the decision to design the facility as a six-lane roadway was
based upon year 2030 traffic projections for a non-toll facility using the Metrolina Regional Travel
Demand Model (Gaston East-West Connector Traffic Forecasting and System Level Analysis for
the Detailed Study Alternatives, Martin/Alexiou/Bryson, April 2007, incorporated by reference).
These were the projections available at the time the designs were started. Subsequent traffic
projections generated using the 2030 Metrolina Regional Travel Demand Model for the project as
a toll facility show that traffic volumes would be less than the 2030 projections for a non-toll
facility (Gaston East-West Connector (U-3321) Traffic Forecasts for Toll Alternatives,
Martin/Alexiou/Bryson, August 2008), incorporated by reference and available on the NCTA Web
site (www.ncturnpike.org/projects/gaston).
If one of the DSAs is selected as the Preferred Alternative, traffic projections will be updated
again and the number of lanes for the project will be reevaluated for the Final EIS. If the
updated traffic projections show that only a four-lane facility is warranted, the two lanes in the
center would be removed. The outside construction footprint and right of way would generally be
the same for a four-lane facility and a six-lane facility.
The conformity determination for the region will need to be updated prior to the completion of the
ROD to change the project to a toll facility with the appropriate number of lanes. The MUMPO
and GUAMPO LRTPs are presently being updated to 2035. The updates to the MUMPO and
GUAMPO LRTPs must be locally approved and federally reviewed by May 2009 (MUMPO Web
site: www.mumpo.org/2035_LRTP.htm). The ROD for the project is estimated to be completed in
the fall of 2010. Prior to the ROD, the NCTA will coordinate with GUAMPO and MUMPO to
ensure the air quality conformity determination for the region includes the project’s design
concept and scope consistent with the Preferred Alternative. For further information regarding
the status of the conformity determination, refer to Section 4.2.2.
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The selection of the No-Build Alternative would require the GUAMPO and MUMPO LRTPs to be
updated to remove the proposed Gaston East-West Connector, and would need to seek other
means to meet the region’s emissions budget for achieving conformance with the SIP.
4.2.5.2 Mobile Source Air Toxics Impact Analysis
Recently, concerns for air toxics impacts have been more frequent on transportation
projects during the NEPA process. Transportation agencies are increasingly expected by
the public and other agencies to address MSAT impacts in their environmental
documents as the science emerges.
MSAT analysis is a continuing area of research where, while much work has been done to
assess the overall health risk of air toxics, many questions remain unanswered. In
particular, the tools and techniques for assessing project-specific health impacts from
MSATs are limited. These limitations impede FHWA's ability to evaluate how mobile
source health risks should factor into project-level decision-making under NEPA.
Also, USEPA has not established regulatory concentration targets for the six relevant
MSAT pollutants appropriate for use in the project development process. FHWA has
several research projects underway to more clearly define potential risks from MSAT
emissions associated with transportation projects. While this research is ongoing, FHWA
requires each NEPA document to qualitatively address MSATs and their relationship to
the specific highway project through a tiered approach (Interim Guidance on Air Toxic
Analysis in NEPA Documents (February 3, 2006), FHWA Web site:
www.fhwa.dot.gov/environment/airtoxic/020306guidmem.htm The FHWA will continue
to monitor the developing research in this emerging field. A qualitative analysis of
MSATs for this project appears in its entirety in Appendix H and in the Final Air
Quality Technical Memorandum for the Gaston East-West Connector (PBS&J, September
2008).
4.2.5.3 Construction Air Quality
Provided that local ordinances for open burning and dust are followed, as described below,
significant air quality impacts due to construction of the proposed project are not anticipated.
The proposed project would be constructed in phases, limiting the overall construction activity
occurring at any one location. There would also be emissions related to construction equipment
and vehicles. However, these impacts related to construction would be temporary.
Open Burning. During construction of any of the DSAs, all materials resulting from clearing
and grubbing, demolition, or other operations will be removed from the project site, burned, or
otherwise disposed of by the contractor. Any burning will be accomplished in accordance with
applicable laws, local ordinances, and regulations of the North Carolina SIP for air quality in
compliance with 15A NCAC 02D.1903. For construction in Mecklenburg County, open burning (if
allowed) will require a permit from the Mecklenburg County LUESA Department of Air Quality,
in accordance with the MCAPCO Section 1.5106.
Dust. Also during construction, measures will be taken to reduce dust generated by construction
when the control of dust is necessary for the protection and comfort of motorists and area
residents. These dust-suppression measures may include watering unpaved work areas,
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temporary and permanent seeding and mulching, covering stockpiled materials, and using
covered haul trucks.
4.2.6 ROAD AND BRIDGE ICING POTENTIAL FROM ALLEN STEAM STATION
AIR POLLUTION CONTROL FACILITY
Duke Energy Corporation’s Allen Steam Station, a major coal-fired power plant, is located
between Southpoint Road and the Catawba River on the Belmont peninsula (Figure 2-8a).
The Allen Steam Station is currently installing air pollution control equipment to comply with
the North Carolina Clean Smokestacks Act of 2002. This Act requires companies to reduce their
smog and haze forming emissions by approximately 75 percent over the next decade. The Allen
Steam Station air pollution control equipment is located north of the main power plant, just
south of Corridor Segments K3B/K3C (Figure 2-9cc).
The air pollution control equipment includes scrubbers for sulfur dioxide control that will emit
steam through a tall stack. In correspondence with NCTA, Duke Energy Corporation raised
concerns that the steam emitted from the stack could result in icing on the nearby proposed
roadway and the associated bridge crossing of the Catawba River (Telephone Interview with
Duke Energy Regional Manager, September 14, 2005).
In response to the concerns, a study was conducted to evaluate the likelihood and extent of
potential icing on the proposed roadways and bridge crossings of the Catawba River for Corridor
Segments K3B/K3C (DSAs 4, 9, 22, 27, 58, 68, 76, and 81) and Corridor Segment K4A (DSAs 5,
23, 64, and 77) (Analysis of Potential Icing Impacts Due to Allen Steam Station SO2 Scrubber –
Gaston East-West Connector, MACTEC, September 2008, incorporated by reference). Corridor
Segments K3B/K3C are located approximately 0.4 miles north/northeast of the air pollution
control equipment, and Corridor Segment K4A is approximately 1.5 miles south/southeast.
The Seasonal/Annual Cooling Tower Impact (SACTI) model developed by the Electric Power
Research Institute was used for the analysis. Data related to the air pollution control equipment
used in the analysis was supplied by Duke Energy Corporation. The model predicted a zero
probability of occurrence of icing within one mile of the scrubber stack, which is where Corridor
Segments K3B/K3C (DSAs 4, 9, 22, 27, 58, 68, 76, and 81) are located. The exhaust gases
released from the tall stack (which is 365 feet high) have a high exit velocity, resulting in a large
distance between the plume and the ground. While fogging (and, therefore, a visible plume) may
occur due to the condensation of water vapor under some atmospheric conditions, such a visible
plume is likely to stay aloft within the vicinity of the stack and, consequently, within the vicinity
of Corridor Segments K3B/K3C (Analysis of Potential Icing Impacts Due to Allen Steam Station
SO2 Scrubber – Gaston East-West Connector, MACTEC, September 2008).
Corridor Segment K4A (DSAs 5, 23, 64, and 77) is 1.5 miles to the south/southeast. Based upon
the predominant wind directions in the area (from the southwest), the majority of visible plumes
are likely to occur to the northeast of the Allen Steam Station. The exhaust from the scrubber
stack is expected to be diluted by drier ambient air as it travels over a longer distance, thereby
reducing the potential for condensation. As such, it is not expected that there would be a
likelihood of any icing events occurring along Corridor Segment K4A (Analysis of Potential Icing
Impacts Due to Allen Steam Station SO2 Scrubber – Gaston East-West Connector, MACTEC,
September 2008).
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4.3 FARMLAND
4.3.1 FARMLAND PROTECTION POLICY ACT
The Farmland Protection Policy Act of 1981 (FPPA) (7 USC 4201),
as amended, and its implementing regulations (7 CFR Part 658) are
intended to minimize the impact federal programs have on the
unnecessary and irreversible conversion of farmland to
non-agricultural uses. To the extent possible, it assures federal
programs are administered to be compatible with state government,
local government, and private programs and policies in order to
protect farmland.
Prime Farmland is land that has the best combination of physical and chemical characteristics
for producing food, feed, fiber, forage, oilseed, and other agricultural crops with minimum inputs
of fuel, fertilizer, pesticides, and labor, and is within allowable soil erosion tolerance or excessive
soil erosion, as determined by US Department of Agriculture (USDA), Natural Resources
Conservation Service (NRCS).
Unique Farmland is land other than prime farmland that is used for the production of specific
high-value food and fiber crops, as determined by NRCS.
Local or Statewide Important Farmland is land other than prime or unique farmland that is
determined to be important by the appropriate state, tribal, or unit of local government agency or
agencies, with concurrence by the State Conservationist.
These definitions refer to areas where the soils are conducive to agricultural production, not just
areas currently or historically used as farmland. According to the FPPA, prime farmland does
not include land already in or committed to urban development or water storage.
4.3.2 PRIME AND IMPORTANT FARMLAND SOILS
The NRCS has published soil surveys for Gaston County and Mecklenburg County. Soils within
the DSA corridors considered by the NRCS to be prime farmland or farmland of statewide
importance are listed in Table 4-8 and shown in Figure 4-2. There are no farmland soils
classified as unique or locally important within the vicinity of the DSAs.
TABLE 4-8: Prime and Important Farmland Soils in the Detailed Study Alternatives
Soil Symbol Soil Name Percent Slope County
Prime Farmland Soils
AmB Alamance Variant gravelly loam 2‐8 Gaston
ApB Appling sand loam 2‐8 Mecklenburg
*CH Chewacla loam – frequently flooded – Gaston
CeB2 Cecil sandy clay loam –eroded 2‐8 Gaston & Mecklenburg
*Co Congaree loam – occasionally flooded – Gaston
DaB Davidson sandy clay loam 2‐8 Mecklenburg
EnB Enon fine sandy loam 2‐8 Mecklenburg
GaB2 Gaston sandy clay loam – eroded 2‐8 Gaston
HeB Helena sandy loam 1‐6 Gaston
Prime Farmland
Land that has the best
characteristics for
producing food, feed, fiber,
forage, oilseed, and other
crops with minimum inputs
of fuel, fertilizer, pesticides,
and labor (Farmland
Protection Policy Act).
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TABLE 4-8: Prime and Important Farmland Soils in the Detailed Study Alternatives
Soil Symbol Soil Name Percent Slope County
HeB Helena sandy loam 2‐8 Mecklenburg
MaB2 Madison sandy clay loam – eroded 2‐8 Gaston
*MO Monacan soils – Mecklenburg
TaB Tatum gravelly loam 2‐8 Gaston
VaB Vance sandy loam 2‐8 Gaston & Mecklenburg
WnB Winnsboro loam 2‐8 Gaston
Statewide Important Farmland Soils
AmD Alamance Variant gravelly loam 8‐15 Gaston
DaD Davidson sandy clay loam 8‐15 Mecklenburg
GaD2 Gaston sandy clay loam – eroded 8‐15 Gaston
LgB Lignum silt loam 1‐6 Gaston
LgB Lignum gravelly silt loam 2‐8 Mecklenburg
MeD Mecklenburg fine sandy loam 8‐15 Mecklenburg
TaD Tatum gravelly loam 8‐15 Gaston
WeD Wedowee sandy loam 6‐15 Gaston
WnD Winnsboro loam 8‐15 Gaston
Sources: Soils Survey of Gaston County, North Carolina (NRCS, May 1989); Soil Survey of Mecklenburg County, North
Carolina (NRCS, June 1980); List of North Carolina Important Farmlands, USDA ftp site: ftp://ftp‐
fc.sc.egov.usda.gov/NC/NCweb/Programs/soilsurvey
*Prime if protected from flooding or not frequently flooded during growing season.
4.3.3 EXISTING AGRICULTURE
4.3.3.1 Census Information
A small percentage (approximately 0.1 percent) of Gaston County’s employment is agricultural,
and for Mecklenburg County the percentage is slightly higher at 0.2 percent (Employment and
Wages by Sector, 2nd Quarter 2007, North Carolina Employment Security Commission).
Approximately 18.3 percent of Gaston County’s land consisted of farms in 2002, while in
Mecklenburg County the land in farms comprised approximately 7.5 percent. The amount of land
consisting of farms in Gaston County increased between 1997 and 2002 (from 37,124 acres to
41,827 acres), while the amount of land consisting of farms in Mecklenburg County decreased
(from 32,377 acres to 25,422 acres).
The number of farms in Gaston County increased from 420 to 450 between 1997 and 2002. For
Mecklenburg County, the number of farms decreased from 377 to 300 between 1997 and 2002
(2002 Census of Agriculture, USDA Agricultural Statistics Service, June 2004).
4.3.3.2 Agricultural Uses in the Detailed Study Alternatives
Approximately 8 to 11 percent of the land within the DSAs is estimated to be currently in
agricultural uses and pine plantation, with the exception of DSA 68, which has approximately
16 percent of its land currently within agricultural use and pine plantation (Natural Resources
Technical Report for the Gaston East-West Connector, Earth Tech, February 2008).
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4.3.3.3 Local Farmland Programs
In July 2004, Gaston County adopted a Voluntary Agricultural District (VAD) ordinance under
the authority of the Agricultural Development and Farmland Preservation Enabling Act (NCGS
Chapter 106 Sections 735-743). The Act authorizes counties and cities to undertake a series of
programs to encourage the preservation of qualifying farmland and to foster the growth,
development, and sustainability of family farms. Mecklenburg County does not have a VAD
program.
Gaston County farmers who enroll their farms in the Gaston County VAD program agree to keep
their lands dedicated to agricultural uses for 10 years, and they have the right to public hearings
in their communities if there are ever land-condemnation proceedings against lands within the
districts (Gaston County Voluntary Agricultural District Ordinance, Gaston County Web site:
www.co.gaston.nc.us/ordinances/VADordinance2004-07-22.pdf)
Parcels participating in the VAD program are generally located within the unincorporated areas
of Gaston County both north and south of I-85, including several parcels within the vicinity of the
DSAs. These parcels are shown in Figure 4-3.
4.3.4 FARMLAND IMPACTS
4.3.4.1 Prime and Important Farmland Soils
All proposed DSAs would involve the use of prime and statewide important farmland soils. The
No-Build Alternative would not directly impact prime and important farmland soils. Table 4-9
presents the acreages of prime and important farmland soils within the preliminary engineering
design right of way for each DSA. The acreages were calculated using GIS by overlaying the
preliminary design right of way on the soils GIS layer and subtracting out disturbed land already
in urban development.
TABLE 4-9: Impacts to Prime and Important Farmland Soils
Prime Farmland Soils
(Acres in Right of Way)*
Statewide Important Farmland Soils
(Acres in Right of Way)*
DSA
Total
Acreage
in DSA
Right of
Way
Gaston Mecklenburg Total
Prime Gaston Mecklenburg Total
Important
Total acreage
of Prime and
Important
Farmland Soils
in DSA
4 1,901 562 131 693 59 20 79 772
5 1,837 554 79 633 51 7 58 691
9 1,893 586 131 717 70 20 90 807
22 1,940 580 131 711 50 20 70 781
23 1,872 571 79 650 42 7 49 699
27 1,931 603 131 734 61 20 81 815
58 2,009 597 131 728 147 20 167 895
64 1,991 563 79 642 216 7 222 864
68 2,047 595 131 726 234 20 254 980
76 1,901 590 131 721 112 20 132 853
77 1,837 581 79 661 104 7 111 772
81 1,893 614 131 745 123 20 143 888
* Acreages are calculated for the preliminary engineering design right of way for each DSA. Areas of prime and statewide important
soils already in urban development were not included in the totals.
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Generally, the alternatives that are farthest west and south have the most prime and important
farmland soils, with DSA 68 having the most total acreage (980 acres) and the highest percentage
(48 percent). DSA 5 has the least acreage (691 acres – 38 percent), while DSA 23 has the lowest
percentage (699 acres – 37 percent).
4.3.4.2 Farmland Conversion Impact Ratings
In accordance with the FPPA and Guidelines for Implementing the Final Rule of the Farmland
Protection Policy Act for Highway Projects (FHWA, May 1989), an NRCS form, “Farmland
Conversion Impact Rating for Corridor Type Projects”, was prepared. The NRCS forms are
included in Appendix I.
The ratings on the forms are comprised of two parts. The Land Evaluation Criterion Value
represents the relative value of the farmland to be converted on a scale from 0 to 100 points. The
Corridor Assessment, which is rated on a scale of 0 to 160 points, evaluates farmland soil based
upon its use in relation to the other land uses and resources in the immediate area. The two
ratings are added together for a possible total rating of 260 points. Sites receiving a total score of
160 points or more are given increasingly higher levels of consideration for protection (7 CFR
Part 658.4).
Table 4-10 lists the total points for each DSA. The total point value for each DSA is less than
160 points. According to the FPPA, lands that receive a combined score of less than 160 points
are not covered by the FPPA. Since the soils impacts by the DSAs do not meet the threshold of
protection based on the evaluation under the FPPA, the impact to prime and statewide important
farmland is not considered under the FPPA.
TABLE 4-10: Farmland Impact Ratings by Detailed Study Alternative
Farmland Value Total Points DSA
Gaston Mecklenburg Gaston Mecklenburg
4 62 62 125 122
5 60 56 121 115
9 62 62 124 122
22 61 62 124 122
23 59 56 120 115
27 61 62 123 122
58 63 62 123 120
64 59 56 121 115
68 62 62 122 120
76 62 62 124 122
77 60 56 121 115
81 62 62 124 122
Source: NRCS Farmland Conversion Impact Rating Forms (Appendix I).
4.3.4.3 Local Agricultural Programs and Farm Relocations
Local Agricultural Programs. There are 21 parcels currently participating in the VAD
program that would be directly impacted by various DSAs. These parcels total approximately
1,109 acres and are mainly concentrated in the area surrounding the intersection of Union Road
and Union New Hope Road. There are additional parcels along Robinson Road near York Road
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and north of Lewis Road near Camp Rotary Road. The No-Build Alternative would not directly
impact any VAD properties.
As shown in Table 4-11, the number of impacted VAD program properties range from 8 to 11,
with impacted acreage ranging from 44.7 to 138.4 acres. DSAs 64 and 68 impact the most
number and acreage of VAD properties, as these DSAs are located in more rural areas. DSAs 4
and 22 would impact the least number and acreage of VAD properties.
Although all DSAs would impact agricultural lands in Gaston County, the project is consistent
with the County’s land use plans, which designate southern Gaston County as an area targeted
for more suburban development. Discussion with Gaston County staff and reviews of local
planning documents indicate that the area surrounding the proposed project is slated for
suburban development.
TABLE 4-11: Impacts to Voluntary Agricultural District
Properties
DSA
# of VAD
Parcels
Impacted*
Acreage
Impacted by
Right of
Way*
Total VAD
Parcel
Acreage*
Impacted Acreage
(%) of Total VAD
Parcel Acreage
4 8 44.7 301.9 15
5 10 49.2 449.1 11
9 10 49.2 449.1 11
22 8 44.7 301.9 15
23 10 49.2 449.1 11
27 10 49.2 449.1 11
58 10 68.8 586.3 12
64 14 138.4 924.3 15
68 14 138.4 924.3 15
76 9 64.0 555.4 12
77 11 68.5 702.6 10
81 11 68.5 702.6 10
* Impacts calculated based on preliminary engineering designs and locations of
VAD parcels provided by Gaston County GIS.
Note: VAD = Voluntary Agricultural District
Farm Relocations. The Relocation Reports for the Gaston East-West Connector (Carolina Land
Acquisitions, Inc., April 2008) for the proposed project (Appendix F) note that two farms,
described below, would require relocation, depending upon the DSA. Because much of southern
Gaston County is still rural, it is anticipated that there would be suitable replacement property
available for farm relocation. The No-Build Alternative would not require relocation of farms.
Duck Crossing Farm, located on Robinson Road, is 190.7 acres in size. The proposed right of way
of the mainline and the Robinson Road interchange in Corridor Segment J1c (DSAs 64 and 68)
would pass through this farm.
White Rock Horse Farm includes 34.4 acres located at the end of Victory Trail, east of Rufus
Ratchford Road. The proposed right of way for the project’s mainline in Corridor Segment K1A
(DSAs 5, 9, 23, 27, 64, 68, 77, and 81) passes through the middle of this farm.
As discussed in Section 7.5.1, future growth in southern Gaston County has the potential to
convert farmlands and other agricultural lands. These effects are projected to occur under both
the DSAs and the No-Build Alternative, but likely at a faster rate with the DSAs.
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4.4 UTILITIES AND INFRASTRUCTURE
Information in this section regarding electric power transmission, natural gas, and
telecommunications is summarized from the Utility Impact Report for the Gaston East-West
Connector (TBE Group, Inc., August 2008), incorporated by reference and available on the NCTA
Web site (www.ncturnpike.org/projects/gaston). Sources for that report included a site
investigation, communication with the existing utility owners, North Carolina One-Call, and data
on the DSA’s preliminary engineering designs provided to the TBE Group. Information
regarding water and sewer services is summarized from the Indirect and Cumulative Effects
Assessment for the Gaston East-West Connector (Louis Berger Group, March 2009), incorporated
by reference and available on the NCTA Web site (www.ncturnpike.org/projects/gaston).
4.4.1 EXISTING CONDITIONS
4.4.1.1 Electric Power
Electric power in the Project Study Area is supplied by
Duke Energy Corporation, Rutherford Electric Membership
Cooperative (EMC), and the City of Gastonia (Utility
Impact Report for the Gaston East-West Connector, TBE
Group, Inc., August 2008). Duke Energy Corporation
provides service in both Gaston and Mecklenburg Counties
and has transmission and distribution lines in the Project
Study Area. Rutherford EMC services western and
southern Gaston County and has local transmission and
distribution lines in the Project Study Area. The City of
Gastonia provides services in their municipal limits and
only has distribution lines.
In addition to Duke Energy Corporation’s Allen Steam Station (Section 2.3.2.2 and Figure 2-
8a), there are major electric power transmission easements in four general locations within and
near the DSAs:
• Western end of the DSAs, north of Linwood Road
• Near US 321
• Near Robinson Road
• At the eastern end of the project, radiating out from Duke Energy’s Allen Steam Station
Six electric power transmission easements within and near the eastern end of the DSAs originate
from the Allen Steam Station. Several of these easements enter and exit the area multiple times.
Each easement may contain one to three power transmission lines.
The electric power transmission lines and easements located within and near the DSAs are
owned by either Duke Energy Corporation or Rutherford EMC. The locations of these easements
are shown on Figure 4-4, and in detail on Figure 2-9a-d, n-r, and y-hh. Electric power
distribution lines also are located throughout the Project Study Area, and are owned by the City
of Gastonia, in addition to the above-mentioned electric power transmission line owners.
Transmission Lines vs Distribution
Lines
Electric power transmission lines
transmit power between a power plant
and a substation near a populated
area. Electric power distribution lines
deliver the power from the substation
to the consumer. This same concept
also applies to other utilities, such as
natural gas and water.
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4.4.1.2 Natural Gas
Natural gas distribution lines are located throughout the Project Study Area and are owned by
either PSNC Energy (Gaston County) or Piedmont Natural Gas (Mecklenburg County).
There are three natural gas transmission line easements that cross the DSAs. These are owned
by Transcontinental Gas Pipeline Corporation, Plantation Pipeline Company, and Colonial
Pipeline Company.
The Transcontinental Gas Pipeline Corporation transmission line easement is located near the
western termini of the DSAs. This easement runs southwest-northeast, and crosses I-85 west of
the existing Edgewood Road interchange. There are three natural gas transmission pipelines
(one 30-inch pipeline and two 36-inch pipelines) in this easement. The Transcontinental Gas
Pipeline Corporation gas transmission line is an interstate gas pipeline regulated by the Federal
Energy Regulatory Commission (FERC) (FERC Web site: www.ferc.gov/industries/gas/gen-
info/reg-ent.asp).
The Plantation Pipeline Company natural gas transmission easement and the Colonial Pipeline
Company easement are parallel to each other. They run southwest-northeast, crossing US 321
near its intersection with Crowders Creek Road. The Plantation Pipeline Company easement
contains two pipelines (size unknown). The Colonial Pipeline Company easement contains two
natural gas transmission pipelines; a 40-inch pipeline and a 36-inch pipeline.
4.4.1.3 Telecommunications
A privately owned communication tower is located just west of US 321 between Superior
Stainless Road to the north and Old Depot Road to the south, and a cell tower is located at the
intersection of Union New Hope Road and NC 274 (Union Road). Various AT&T (formerly
BellSouth) and Time Warner Cable telecommunication lines cross the Project Study Area.
4.4.1.4 Water and Sewer Facilities
The City of Gastonia, City of Bessemer City, City of Belmont, and the Charlotte-Mecklenburg
Utilities Division have existing and planned water and sewer facilities within and near the DSAs.
Figure 4-4 displays the existing and planned water and sewer service areas in relation to the
DSAs. As shown in the figure, water and sewer services are provided in the DSA areas from I-85
south to Linwood Road, around US 321, and in Mecklenburg County. Most of the planned
expansions are located in southern Gaston County. Areas not provided public water and sewer
use private or community wells and septic systems.
The City of Gastonia provides public water and sewer service for a large area and regularly
extends lines to meet the needs of new developments, particularly in the southern part of the city.
The City’s water comes from Mountain Island Lake on the Catawba River (City of Gastonia Web
site: www.cityofgastonia.com/city_serv/pwu/utilities/treatment/treatment.cfm).
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The City of Bessemer City provides public water and sewer services within its municipal
boundaries. The City’s water comes from Long Creek, and is stored in Arrowood Lake (Telephone
interview with City of Bessemer City Water Treatment Plant staff, October 15, 2008).
The City of Belmont offers water and sewer services within its municipal boundaries. The City’s
water comes from Lake Wylie on the Catawba River (City of Belmont Web site:
www.cityofbelmont.org/department-watertreatment.aspx). The City has extended its water
facilities south along NC 273 (Southpoint Road) to the end of the peninsula in order to serve new
subdivisions. Areas along NC 273 (Southpoint Road) not currently served by city utilities can tap
into the new line if annexed into the City.
Charlotte-Mecklenburg Utilities provides water and sewer throughout Mecklenburg County.
Charlotte-Mecklenburg Utilities withdraws water from Lake Norman and Mountain Island Lake
on the Catawba River (Charlotte-Mecklenburg Utilities Web site:
www.charmeck.org/Departments/Utilities/Divisions/supplyandtreat.htm). Within Mecklenburg
County, part of the Project Study Area is serviced by both water and sewer, and a portion
(nearest the Catawba River) is served only by sewer.
4.4.1.5 Railroads
There are three railroad lines within the vicinity of the DSAs. The most active rail line is the
Norfolk Southern line shown on Figure 2-9c paralleling the east side of NC 274 (Bessemer City
Road) as it crosses over I-85. This is the Washington, D.C., to Atlanta, Georgia, mainline. This
mainline handles up to 40 freight trains and two passenger trains per day, with maximum train
speeds of 79 miles per hour (mph). This track also has been designated as part of the future
Southeast High Speed Rail Corridor from Washington, D.C., to Atlanta, Georgia (NCDOT Rail
Division Scoping Letter, May 12, 2003, included in Appendix A-3).
There is a Norfolk Southern branch line running north-south parallel to the east side of US 321.
This line is shown in Figure 2-9n-p. This is a lightly used branch line with maximum train
speeds of 10 mph (NCDOT Rail Division Scoping Letter, May 12, 2003, included in Appendix A-
3).
The third line is a spur line that serves Duke Energy Corporation’s Allen Steam Station. This
line runs along the west side of the Catawba River from the Norfolk Southern mainline south
through Belmont to the Allen Steam Station. This spur line can be seen on Figure 2-9cc.
4.4.2 IMPACTS TO UTILITIES
Table 4-12 summarizes the major utility impacts estimated for the DSAs, based upon the
preliminary engineering designs. Major utility impacts were defined as utility conflicts estimated
to cost $250,000 or more to relocate or modify (Utility Impact Report for the Gaston East-West
Connector, TBE Group, Inc., August 2008). The No-Build Alternative would not create utility
impacts.
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TABLE 4-12: Major Utility Impacts
Detailed Study Alternative Utility
4 5 9 22 23 27 58 64 68 76 77 81
Electric Power Transmission
Lines – # of Crossings1 14 13 14 14 13 14 18 17 17 17 15 17
Natural Gas Transmission
Pipelines – # of Crossings2 4 4 4 4 4 4 4 4 4 4 4 4
Telecommunications Towers –
# of Impacted Towers 0 0 0 0 0 0 0 0 0 0 0 0
Railroads – #of Crossings 2 1 2 2 1 2 2 1 2 2 1 2
Source: Utility Impact Report for the Gaston East‐West Connector (TBE Group, Inc., August, 2008).
1. There may be one to three individual lines in a power transmission easement. This table reports the numbers of individual
transmission line crossings.
2. The four gas transmission pipeline crossings are located in the two easements (two pipelines in each easement) that cross US 321
near Crowders Creek Road and are owned by Plantation Pipeline Company and Colonial Pipeline Company.
Electrical Power Generation and Transmission. None of the DSAs would directly impact
the Duke Power Corporation’s Allen Steam Station. The number of crossings of electrical power
transmission lines varies from a minimum of 13 (DSA 5 and DSA 23) to a maximum of 18
(DSA 58). The DSAs also cross numerous smaller distribution lines.
The preliminary engineering designs for the DSAs minimized impacts to electric power
transmission lines to the extent feasible, based upon data available at the time. During final
design of the Preferred Alternative, additional opportunities to minimize conflicts with electric
power facilities will be investigated.
Any modifications to the high-voltage electric power transmission lines necessary to
accommodate the proposed project are not expected to adversely impact the transmission lines or
consumer electrical service in the area. Any impacts and relocations of power transmission lines
or towers would be coordinated with Duke Energy Corporation and the Rutherford EMC during
final design of the Preferred Alternative. Impacts to distribution lines would be coordinated with
Duke Energy Corporation, Rutherford EMC, and the City of Gastonia prior to construction.
Natural Gas. All DSAs would cross the natural gas transmission easements owned by
Plantation Pipeline Company and Colonial Pipeline Company described in Section 4.4.1.2. Each
easement contains two natural gas transmission pipelines. The preliminary engineering designs
in the DSAs do not encroach on the easement owned by the Transcontinental Gas Pipeline
Corporation. The DSAs also cross numerous natural gas distribution lines.
Although both natural gas transmission and distribution lines would be crossed by the DSAs, the
project is not expected to impact consumer gas service. To avoid disruptions in service and
delivery, the NCTA would coordinate any required relocation or modification of transmission
lines with Plantation Pipeline Company and Colonial Pipeline Company and any required
relocation or modification of distribution lines with area providers, including PSNC Energy and
Piedmont Natural Gas.
Telecommunications. Neither the communication tower nor the cell tower near the DSAs is
anticipated to be impacted by any of the DSAs. During final design of the Preferred Alternative,
all telecommunication utility providers will be consulted to ensure that the proposed design and
construction of the project would not substantially disrupt service.
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Water Service. Most of the land in Gaston and Mecklenburg County crossed by the DSAs does
not have public water service. Those areas that do have service are located between I-85 and
Linwood Road and an area east of US 321. A small area in Belmont crossed by Corridor
Segments KX1 and K3A (DSAs 4, 9, 22, 27, 58, 68, 76, and 81) also is served by public water
(Figure 4-4). The remaining areas crossed by the DSAs are served by private or community
wells. Also, all DSAs would cross the public water line installed along Southpoint Road that
extends to the end of the peninsula.
In the areas served by public water, the DSAs would cross water lines, but water service is not
expected to be disrupted. Prior to project construction, the NCTA will coordinate any water line
relocation or reconfiguration with the appropriate municipality or county.
Wells within the Preferred Alternative’s right of way would be surveyed prior to project
construction. NCTA would purchase these wells and cap and abandon them in accordance with
State standards (15A NCAC 2C). Any subsurface contamination would be reported to the
regional office of the NCDENR.
Sewer Service. Most of the areas crossed by the DSAs do not have public sewer service. Those
areas that do are located in the western end of the project, around US 321, and in Mecklenburg
County (Figure 4-4). The DSAs that use Corridor Segment H3 (DSAs 4, 5, and 9) would cross
the most area served by public sewer. The remainder of the Project Study Area is served by
private septic tanks or community treatment systems.
None of the DSAs would impact sewage treatment facilities or public sewer service within the
Project Study Area. Any sewer line relocation or reconfiguration required for construction of the
Preferred Alternative will be coordinated with the affected municipalities or counties, and is not
expected to disrupt service.
Railroads. The Norfolk Southern mainline that runs east-west through Gaston County would
be impacted by DSAs that use Corridor Segment H2A (DSAs 4, 5, 9, 22, 23, and 27). As shown in
Figure 2-9c, the track is close to, and parallels, the east side of NC 274 (Bessemer City Road).
Because the proposed Gaston East-West Connector/I-85 interchange in Corridor Segment H2A is
close to the I-85/NC 274 (Bessemer City Road) interchange, the I-85/NC 274 (Bessemer City
Road) interchange ramps and the mainline of I-85 need to be modified to accommodate the new
interchange to the west. Modifications will require the replacement of the existing railroad
bridge over I-85. It is expected that the replacement bridge can be built in the existing bridge
location, with a temporary detour bridge constructed immediately to the east during the bridge
construction. Substantial disruptions in rail service are not anticipated.
All DSAs cross the Norfolk Southern branch line that runs north-south parallel to the east side of
US 321. The interchange design at US 321 for all DSAs has the ramps located on the west side of
US 321 to avoid the rail line.
The DSAs that use Corridor Segment K3B (DSAs 4, 9, 22, 27, 58, 68, 76, and 81) would cross the
rail spur that serves Duke Energy’s Allen Steam Station.
If DSA 4, 5, 9, 22, 23, or 27 is selected as the Preferred Alternative, additional coordination would
be conducted regarding the Norfolk Southern mainline near I-85. Final design of the Preferred
Alternative will be coordinated with the NCDOT Rail Division and Norfolk Southern to ensure
that the grade-separated crossing of the branch rail line near US 321 and the rail spur
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incorporates the appropriate horizontal and vertical clearances, in accordance with current
standards.
4.5 VISUAL RESOURCES
4.5.1 INTRODUCTION
The area within the vicinity of the DSAs is characterized by gently rolling to steep hills. Land
uses surrounding and within the DSAs are mixed, ranging from agricultural and pasture land to
residential, recreational, industrial, and commercial developments. Commercial and retail
development is limited primarily to the areas located near I-85, US 29-74, and US 321. The
Project Study Area is experiencing growth, including the development of several new housing
developments, with much of the area slowly shifting toward a more suburban environment.
People with views from the project and those with views of the project are addressed in this
section, as both types of viewers have the potential to experience impacts. The views from the
DSAs are comprised of areas that would be visible to travelers on the roadway, including views of
the roadway right of way and beyond. Views of the DSAs were considered for residential areas
and travelers on surrounding roadways, boaters and residents along the South Fork Catawba
River and Catawba River, and visitors to Crowders Mountain State Park and Daniel Stowe
Botanical Garden.
4.5.2 LOCAL ZONING DISTRICTS AND OVERLAY DISTRICTS
The Gaston County Planning Board adopted its Unified Development Ordinance (UDO) in April
2008. The UDO became effective July 1, 2008. The purpose of the UDO is to “raise the standards
for development in the County by working with local municipalities to promote quality,
uniformity, and consistency in development standards throughout the County.” (UDO Purpose
and Acknowledgement section, Gaston County Web site:
www.co.gaston.nc.us/planning/UDO/adoptedUDO/adoptedUDO.htm).
There is one general zoning district and two overlay districts defined in the UDO relevant to the
Gaston East-West Connector and visual impacts. These are the Garden Parkway Interchange
District, Garden Parkway Overlay District, and Scenic View Overlay District. These regulations
supplement those that are found in the underlying general zoning district.” (UDO Section 6.1C).
Garden Parkway Interchange (GPX) District, a general zoning district, is intended to
accommodate an array of aesthetically pleasing and well-designed mixed-use developments that
are located in proximity to the Gaston East-West Connector interchanges (UDO Section G). This
district is “not intended to accommodate nor promote typical strip commercial development.”
(UDO Section G).
Garden Parkway (GP) Overlay District is intended to “maintain an aesthetic viewshed for
motorists and landowners along the length of the Garden Parkway. Any GP Overlay District
initially established shall….consist of all lots fronting along the Garden Parkway for a depth of
five hundred (500) feet on each side of the Garden Parkway as measured from the centerline.”
(UDO Section 6.3.12).
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The GP Overlay District includes several development restrictions. Special landscaping is
required for properties (excluding residential and agricultural uses) that lie adjacent to or are
otherwise visible from the Garden Parkway. Building articulation, materials, and colors are
restricted for building facades that face the Garden Parkway. In addition, rooftop equipment
must not be visible by motorists (UDO Section 7.6.7).
Scenic View (SV) Overlay District was established to protect the scenic views from within the
Daniel Stowe Botanical Garden. Building heights in this overlay district are limited to 35 feet
(excluding single-family and two-family structures), and telecommunication towers and facilities
are not permitted.
The Scenic View Overlay District is delineated on the Gaston County Official Zoning Map
adopted May 2008 (Gaston County Web site:
www.co.gaston.nc.us/planning/UDO/adoptedUDO/adoptedUDO.htm). The Scenic View Overlay
District in relation to the DSAs is shown on Figure 4-5. Several Corridor Segments are located
within the Scenic View Overlay District. These are Corridors Segment K3A (DSAs 9, 27, 68, and
81) and Corridors Segments K1B-K1C-K4A (DSAs 5, 23, 64, and 77). Corridor Segment K2A
(DSAs 4, 22, 58, and 76) encroaches slightly on the northernmost boundary of the overlay district
west of NC 279 (South New Hope Road).
4.5.3 VISUAL IMPACTS
Travelers Using the Gaston East-West Connector. Each of the DSAs has the potential to
offer users of the proposed project visually pleasing views of the project and its surroundings,
such as valleys, hills, wooded areas, farmlands, streams, and cultural features. During the final
design of the Preferred Alternative, NCTA will incorporate a landscaping plan into the project
that will enhance views within the right of way. Gaston County has demonstrated its intention
to maintain aesthetic and visually pleasing development immediately surrounding the proposed
project through the establishment of the GPX District and the GP Overlay District in the UDO.
Users of Surrounding Roadways and Residential Areas. For people in the residential
areas and on roadways surrounding the DSAs, the DSAs’ fill slopes and structures have the
potential to detract from existing views. However, due to natural changes in elevation, the
project’s cut slopes in areas outside of floodplains, and tall trees within the area, much of the
roadway would not be visible from areas outside the project’s immediate vicinity.
Overall, visual changes would be intermittent, with some residents subjected to a view of the
roadway, and other views shielded by the cut/fill areas, forested areas, and project landscaping.
DSAs that have a higher number of neighborhoods exposed to the roadway (i.e., impact a greater
number of neighborhoods with residential relocations) (Section 3.2.4) were estimated to have a
greater degree of visual impacts. Based on these assumptions, it was estimated DSAs 4 and 5
would have the most visual impacts and DSAs 27 and 81 would have the least.
Some areas affected by the DSAs are generally not rural or scenic, so the degree of visual impact
would be less in these locations. These areas include more urban development that occurs
around I-85 near Bessemer City, and along the major roads that would be served by interchanges
(i.e., US 29-74 and US 321). All DSAs pass through these areas.
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The project’s landscaping plan and the zoning requirements of the Garden Parkway Interchange
District and Garden Parkway Overlay District also will enhance and maintain aesthetics for
these viewer groups, as well as those using the Gaston East-West Connector.
Boaters and Residents along the South Fork Catawba River and Catawba River. All
the DSAs would construct bridges over the South Fork Catawba River and Catawba River.
Boaters on these rivers, as well as some riverfront and nearby residents would experience a
substantial change in those views found within the vicinity of the bridges. During final design for
the Preferred Alternative, NCTA will investigate the feasibility and reasonableness of
incorporating cost-effective treatments for the bridge sides, piers, and railings in order to
enhance aesthetics.
Visitors to the Daniel Stowe Botanical Garden. The Daniel Stowe Botanical Garden
(DSBG) is located off NC 279 (South New Hope Road) and south of Corridor Segment K1C (DSAs
5, 23, 64, and 77). None of the DSAs are anticipated to adversely impact the Botanical Garden, or
be close enough to be visible from the areas of the DSBG open to the public. The general zoning
and overlay districts established in the UDO (Scenic View Overlay District, GP Overlay District,
and GPX District) will help preserve and enhance views and aesthetics along the routes to the
DSBG. No visual impacts to the DSBG are anticipated with any of the DSAs.
Visitors in Crowders Mountain State Park. None of the DSAs would directly impact
Crowders Mountain State Park—a natural, forested park that offers hiking and other nature-
related activities. The nearest corridor is Corridor Segment H1A (DSAs 58, 64, 68, 76, 77, and
81), which is located roughly one straight-line mile from the top of Crowders Mountain. The
nearest park boundary is approximately 1,500 feet from the centerline of Corridor Segment H1A.
The nearest point on the hiking trails is on the Tower Trail, which is approximately 2,800 feet
from the centerline of Corridor Segment H1A.
The park’s appeal includes views of the surrounding region, and there are areas of the park that
would experience a change in existing viewsheds. The northeast overlook, Summit Tower, Rock
Top Trail, and Tower Trail each have the potential to offer full or limited views of the proposed
project from locations along the trails and/or summit where views to the east are possible. The
most visible DSAs would likely be those nearest the park. However, the existing viewshed in this
direction includes both rural and developed suburban landscapes. Although viewers may notice
an immediate change with construction of any of the DSAs, it is anticipated that over time, the
proposed project would blend with the suburbanizing landscape that is expected to develop with
the DSAs or without (No-Build Alternative).
4.6 HAZARDOUS MATERIALS
4.6.1 EXISTING CONDITIONS
An assessment of the Project Study Area was performed to identify the presence of potentially
contaminated sites. The NCDOT Geotechnical Engineering Unit prepared a GeoEnvironmental
Impact Study Hazardous Material Evaluation in March 2004, to assist in preliminary corridor
development. The NCDOT Geotechnical Engineering Unit updated the study and evaluated
potential impacts in a memo titled: GeoEnvironmental Impact Evaluation – EDR Study Area
Combined GIE (January 2008). These two memoranda are incorporated by reference.
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The State’s geographic information system (GIS) database was used to identify known hazardous
materials/waste sites within the vicinity of the proposed project. In addition, a search was
conducted by Environmental Data Resources Inc. (EDR), of state and federal databases in
December 2007. The results of these GIS and database searches were compared with existing
and new development and the Gaston County GIS database to determine the current validity of
known contaminated sites. Small, single-incident spills associated with residential heating tanks
were not included in this summary.
Forty-six sites were identified within the immediate vicinity of
the DSAs. Figure 4-6 shows the approximate locations of the
sites. Appendix J (Table J-1) provides general information on
each of the sites. The 46 sites include 25 Underground Storage
Tanks (UST), twelve manufacturing facilities, three junkyards,
two hazardous waste sites, one apparent landfill, and three
other contaminated sites.
Additional details on the two hazardous waste sites (Sites 33 and 34 on Figure 4-6) are provided
below. An additional three sites listed in Appendix J are located within the vicinity of Corridor
Segment K1D, which was eliminated from detailed study (Section 2.3.4.2). These sites were
included in the appendix and figure to avoid confusion that may occur due to discontinuous site
numbering if they were deleted from the list. The site numbers correspond to those in
GeoEnvironmental Impact Evaluation – EDR Study Area Combined GIE (NCDOT Geotechnical
Engineering Unit, January 2008)
Woody’s Tire Fire site is located on the west side of US 321 between James Street and Southside
Church Road on the south edge of Corridor Segments J2a/J3/J4a. According to the
Comprehensive Environmental Response, Compensation and Liability Information System
(CERCLIS) (USEPA Web site: http://cfpub.epa.gov/supercpad/cursites/srchsites.cfm), the site was
archived in August 2004, and is currently listed as an inactive hazardous waste site. The Archive
designation indicates that, based upon available information, the site has no further interest
under the Federal Superfund Program.
This former 1.5-acre site of Woody’s Tire & Used Cars was being used to store roughly 50,000–
100,000 tires at the time of the fire. The fire was discovered on September 12, 1988.
Approximately 1 million gallons of water were used in efforts to extinguish the fire, but
ultimately 2 to 3 feet of soil cover was needed to extinguish the fire. Drainage ditches excavated
to contain the water showed substantial amounts of volatiles and polynuclear aromatics, but no
contamination was found in the nearby unnamed creek. Contamination still exists at the site
and excavation of the soil cover and burnt-tire residue would require special handling if the site
was disturbed during construction of the project.
The AB Carter, Inc. site is located on the east side of US 321, south of the Woody’s Tire Fire site.
This site is on the south side of DSA Corridor Segments J2A/J3/J4A. AB Carter, Inc. generated,
treated, and land-disposed wastewater and sludge from a chroming and nickel plating operation
for textile machinery. Soil, groundwater, and surface water contamination may be expected from
unlined sludge basins. The site is currently an inactive Superfund site.
The locations for Sites 30, 31, and 36 could not be verified. Site 30 is located on Crowders Creek
Road, but no specific address was available in the databases. Bruce’s County Landfill (Site 31) is
likely located east of US 321 (Figure 4-6) within or near DSA Corridor Segments J2b/J3/J4b.
Leaking USTs
Old USTs at service stations
can deteriorate and leak fuels,
and are a common source of
soil and/or groundwater
contamination.
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-40
Site 36 is likely east of US 321 and south of Forbes Road. Since the boundaries and exact
locations of the landfill and Site 30 are not known at this time, the locations would need to be
verified if DSA 4, 5, 9, 22, 23, or 27 is selected as the Preferred Alternative. If DSA 58, 64, or 68
is selected as the Preferred Alternative, the location of Site 36 would need to be verified.
4.6.2 IMPACTS FROM HAZARDOUS MATERIALS/WASTE SITES
The NCDOT Geotechnical Engineering Unit evaluated the sites listed in Appendix J to
determine the magnitude of anticipated impact if the project would directly affect the site.
Table 4-13 summarizes the impacts of the potentially contaminated sites for each DSA. Those
sites listed in Appendix J with an anticipated type of impact of “none” were not included in the
table. Because there is some uncertainty as to the exact locations of the sites, if the site was
mapped as within the DSA corridors, it was assumed to be an impact. The DSAs’ preliminary
engineering designs were prepared to avoid known hazardous materials/waste sites to the extent
possible. The No-Build Alternative would not impact any sites.
Table 4-13 includes the potential anticipated impact level and the type of contamination
expected to be encountered at each site. Anticipated impacts were rated low, medium, or high, as
defined below:
• Low – Little to no impacts to cost or schedule anticipated.
• Medium – Additional costs and time may be incurred due to the handling of contaminated
materials, and a need for special construction techniques or products.
• High – Costs and scheduling could overwhelm smaller projects and cause serious delays
in larger projects. Liability may fall upon the NCTA to clean up contamination, which
could require decades. These sites should be avoided to the extent possible. There were
no sites within the DSAs that received a “high” impact rating.
TABLE 4-13: Impact on Potentially Contaminated Sites by Detailed Study Alternative
Detailed Study Alternative Site
Number
Anticipated
Type of
Impact
Anticipated
Impact
Severity 4 5 9 22 23 27 58 64 68 76 77 81
Site 1: UST
Petroleum
Contaminated
Soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X X X X
Site 2: UST
Petroleum
Contaminated
Soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X X X X
Site 3:
GWI/
Manuf.
Contaminated
groundwater Medium X X X X X X X X X X X X
Site 6: UST
Petroleum
Contaminated
Soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 7: UST
Petroleum
Contaminated
Soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 9: UST
Petroleum
Contaminated
Soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-41
TABLE 4-13: Impact on Potentially Contaminated Sites by Detailed Study Alternative
Detailed Study Alternative Site
Number
Anticipated
Type of
Impact
Anticipated
Impact
Severity 4 5 9 22 23 27 58 64 68 76 77 81
Site 10: UST
Petroleum
Contaminated
Soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 11: UST
Petroleum
contaminated
soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 12: UST
Petroleum
contaminated
soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 14:
UST/Manuf.
Petroleum
contaminated
soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 16:
Manuf. Chemicals Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 17: UST
Petroleum
contaminated
soils
Low X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 18:
Junkyard
Petroleum
contaminated
soils
Low to
Medium X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 19:
Junkyard/
UST
Petroleum
contaminated
soils
Low to
Medium X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 20:
Junkyard
Petroleum
contaminated
soils
Low to
Medium X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 21: UST
Petroleum
contaminated
soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X X X X
Site 22: UST
Petroleum
contaminated
soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X X X X
Site 23:
Manuf.
Contaminated
groundwater Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X X X X
Site 26: UST
Petroleum
contaminated
soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X ‐‐ ‐‐ ‐‐
Site 27:
UST/Manuf.
Petroleum
contaminated
soils
Low X X X -- -- -- ‐‐ ‐‐ ‐‐ -- -- -
Site 28:
UST/Manuf.
Petroleum
contaminated
soils and
chemicals
Low to
Medium X X X X X X ‐‐ ‐‐ ‐‐ X X X
Site 29: GWI Contaminated
groundwater Low X X X X X X ‐‐ ‐‐ ‐‐ X X X
Site 30: UST
and Manuf.
Petroleum
contaminated
soils
Low X X X -- -- -- ‐‐ ‐‐ ‐‐ -- -- --
Site 31:
Land Fill
Landfill
material Low X X X X X X ‐‐ ‐‐ ‐‐ X X X
Site 33:
Haz Waste
Facility
Contaminated
soils
Low to
Medium X X X X X X ‐‐ ‐‐ ‐‐ X X X
PHYSICAL ENVIRONMENT Chapter 4
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TABLE 4-13: Impact on Potentially Contaminated Sites by Detailed Study Alternative
Detailed Study Alternative Site
Number
Anticipated
Type of
Impact
Anticipated
Impact
Severity 4 5 9 22 23 27 58 64 68 76 77 81
Site 34:
Haz Waste
Facility
Soil and
groundwater
contaminatio
n
Medium X X X X X X ‐‐ ‐‐ ‐‐ X X X
Site 35:
UST/Manuf.
Petroleum
contaminated
soils and
groundwater
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X ‐‐ ‐‐ ‐‐
Site 36: GWI Contaminated
groundwater Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X ‐‐ ‐‐ ‐‐
Site 37: UST
Petroleum
contaminated
soils
Low ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ X X X ‐‐ ‐‐ ‐‐
Site 38: UST
Petroleum
contaminated
soils
Low X X X X X X X ‐‐ ‐‐ ‐‐ ‐‐ ‐‐
Site 41: UST
Petroleum
contaminated
soils
Low X ‐‐ X X ‐‐ X X ‐‐ X X ‐‐ X
Site 47: UST
Petroleum
contaminated
soils
Low X X X X X X X X X X X X
Site 48: UST
Petroleum
contaminated
soils and
groundwater
Low X X X X X X X X X X X X
Sites Within DSA Corridor 24 23 24 22 21 22 14 12 13 14 13 14
Sites with Low Impact Severity 17 16 17 15 14 15 13 11 12 10 9 10
Sites with Low ‐Medium Impact Severity 5 5 5 5 5 5 0 0 0 2 2 2
Sites with Medium Impact Severity 2 2 2 2 2 2 1 1 1 2 2 2
Source: NCDOT Geotechnical Engineering Unit, 2008.
The potentially contaminated sites within the DSA corridors are defined as having a low, low-to-
medium, or medium anticipated impact severity, and no sites have an anticipated impact severity
of high. Regardless of the DSA, the potentially impacted sites are generally concentrated around
I-85, US 29-74, and US 321, and scattered sites in other locations.
Based upon the assessment described above, the DSAs are listed below from the smallest to
largest numbers of potentially contaminated sites. Generally, the DSAs closest to the west side
of Gastonia had the highest numbers of potentially contaminated sites.
• DSA 64 (12 sites)
• DSAs 68 and 77 (13 sites)
• DSAs 58, 76 and 81 (14 sites)
• DSA 23 (21 sites)
• DSAs 22 and 27 (22 sites)
• DSA 5 (23 sites)
• DSAs 4 and 9 (24 sites)
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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-43
4.6.3 MITIGATION FOR HAZARDOUS MATERIALS/WASTE SITES
Once a Preferred Alternative is selected, a more detailed field reconnaissance will be conducted to
include unregulated sites with potential contamination in the assessment. Additional sites not
recorded by regulatory agencies and not reasonably discernable during project reconnaissance
may occur. Soil and groundwater assessments will be conducted on each of the potentially
contaminated properties within the Preferred Alternative before right-of-way acquisition in order
that the degree and extent of contamination can be assessed.
4.7 FLOODPLAINS AND FLOODWAYS
4.7.1 BACKGROUND INFORMATION
Riverine floodplains are low-lying areas adjacent to
stream channels that are prone to periodic flooding during
heavy or prolonged rains. The 100-year floodplain is the
area that has a one percent chance of flooding during any
given year.
The floodway is the channel area that needs to be kept
free of encroachment so the 100-year flood can be carried
without increasing the level and extent of flood
elevations. Streams for which detailed hydrological
studies have not been conducted do not have defined
floodways, so only the 100-year floodplain boundaries are estimated and mapped.
A floodplain evaluation was conducted for the project in accordance with Executive Order 11988 –
Floodplain Management, and 23 CFR Part 650, Subpart A – Location and Hydraulic Design of
Encroachments on Floodplains. Both Gaston and Mecklenburg Counties are participants in the
National Flood Insurance Program (NFIP) administered by the Federal Emergency Management
Administration (FEMA). As part of the NFIP, FEMA determines floodway boundaries as a tool
for floodplain management.
FEMA, in cooperation with federal, state and local governments, developed floodplain and
floodway boundaries and Flood Insurance Rate Maps (FIRM) for Gaston County in September
2007 (Gaston County Web site: www.co.gaston.nc.us/planning/maps/firms/firm.htm), and
Mecklenburg County in February 2004 (Charlotte-Mecklenburg Web site:
www.charmeck.org/departments/stormwater/flood+zone/what+are+floodplain+maps+used+for%3
f.htm).
4.7.2 FLOODPLAINS AND FLOODWAYS IN THE PROJECT STUDY AREA
Figure 4-7 shows the floodplains and floodways in southern Gaston County and western
Mecklenburg County. Named streams with floodplains and floodways include, from west to east:
Abernethy Creek, Oates Branch, Bessemer Branch, Crowders Creek, Blackwood Creek, Ferguson
Branch (floodplain only), McGill Branch (floodplain only), South Crowders Creek (floodplain
only), Catawba Creek, South Fork Catawba River, Catawba River, Beaverdam Creek, and Legion
100‐Year Floodplains and Floodways
The 100‐year floodplain is the area that
has a 1 percent chance of flooding
during any given year.
The floodway is the channel area that
needs to be kept free of encroachment
so the 100‐year flood can be carried
without increasing the level and extent
of flood elevations.
PHYSICAL ENVIRONMENT Chapter 4
APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-44
Lake Stream. Several unnamed tributaries of Crowders Creek and Catawba Creek also have
defined floodplains.
Defined floodways generally are located within or near municipal limits. For example, Crowders
Creek has a defined floodway from its confluence with Abernethy Creek near US 29-74
downstream to the confluence with Blackwood Creek. South of this point, a detailed study has
not been prepared to define the floodway.
4.7.3 FLOODWAY/FLOODPLAIN IMPACTS AND MAJOR DRAINAGE
STRUCTURES
A preliminary hydraulics analysis was performed to identify the preliminary sizes and locations
of major drainage structures along the DSAs that would be needed to adequately carry
floodwaters. Major drainage structures are bridges, box culverts, or pipe culverts greater than 72
inches in diameter. The preliminary hydraulic analysis is presented in the Final Preliminary
Hydraulic Technical Memorandum for the Gaston County East-West Connector (PBS&J,
December 2007), incorporated by reference and available on the NCTA Web site
(www.ncturnpike.org/projects/gaston).
For all DSAs together, the preliminary hydraulics analysis identified 122 crossings of streams
and drainages for which bridges, box culverts, or pipe culverts greater than 72 inches in diameter
would be required from a hydraulics standpoint.
The major drainage structures and crossings were reviewed by the environmental regulatory and
resource agencies at Turnpike Environmental Agency Coordination Meetings on February 5,
March 4, and April 8, 2008 (Section 9.2.3.3). As a result of these meetings, the NCTA agreed to
include several bridges in the preliminary engineering designs beyond those required to convey
floodwaters. At the following locations, culverts were upgraded to bridges in the preliminary
engineering designs for the DSAs to avoid or minimize stream and wetland impacts.
• Corridor Segment H2A (DSAs 4, 5, 9, 22, 23, and 27) – bridge the service road over
Bessemer Branch (Stream S25).
• Corridor Segment H2C (DSAs 22, 23, and 27) – lengthen the mainline bridges over
Chapel Grove Road to span Stream S70.
• Corridor Segment HX2 (DSAs 76, 77, and 81) – lengthen the mainline bridges over Camp
Rotary Road to span Stream S79.
• Corridor Segment H3 (DSAs 4, 5, and 9) – bridge Blackwood Creek (Stream S135).
• Corridor Segments J3 and J2a (DSAs 22, 23, 27, 76, 77, and 81) – lengthen the bridge
over Crowders Creek (Stream S14) to span Wetland 103.
• Corridor Segment J1c (DSAs 64 and 68) – bridge Stream S178 (unnamed tributary to
Crowders Creek).
• Corridor Segment K3A (DSAs 9, 27, 68, and 81) – lengthen the mainline bridge over
Catawba Creek (Stream S259) to span the main body of Wetland W248. This extension
also avoids impacts to Catawba River buffer areas on the east side of the creek.
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APRIL 2009 GASTON EAST-WEST CONNECTOR DEIS 4-45
• Corridor Segment K1B (DSAs 5, 23, 64, and 77) – lengthen the mainline bridge over
Catawba Creek (Stream S259) to span the main body of Wetland W248. This extension
also avoids impacts to Catawba River buffer areas on the east side of the creek.
Figure 4-8 shows the locations of the major drainage structures along the DSAs. Table 4-14
summarizes the numbers of major drainage structures associated with each DSA. Details about
the major drainage structures, such as structure size, stream crossed, drainage area, and flow
rate, are included as a table in Appendix K. The locations labeled in Figure 4-8 correspond to
the labels in the table in Appendix K.
TABLE 4-14: Summary of Major Drainage Structures and Floodway and Floodplain
Crossings
DSA
Number of
Bridge Crossings
Over Streams1
Number of Major
Culverts or Pipes
(> 72 inches in
diameter)2
Number of
Floodway
Crossings
Number of
Floodplain
Crossings3
Number of Longitudinal
Floodplain Encroachments
and Total Encroachment
Area4
4 7 47 10 12 1 (5 acres)
5 7 43 10 13 1 (5 acres)
9 7 45 10 13 1 (5 acres)
22 8 45 9 12 0
23 8 41 9 13 0
27 8 43 9 13 0
58 6 47 7 11 0
64 7 42 7 12 0
68 7 44 7 12 0
76 7 42 7 10 0
77 7 39 7 11 0
81 7 40 7 11 0
Sources: Final Preliminary Hydraulic Technical Memorandum for the Gaston County East‐West Connector (PBS&J,
December 2007) and the meeting minutes from the Turnpike Environmental Agency Coordination Meeting held April 8,
2008.
1. For DSAs 4, 5, 9, 22, 23, and 27, bridge crossings include the service road bridge over Bessemer Branch. For DSAs 4, 5,
and 9, bridge crossings include a bridge for the realignment of Linwood Road over Crowders Creek.
2. The numbers for major culverts and pipes include all of the multiple culverts/pipes required at interchanges.
3. The preliminary engineering designs for all the DSAs would involve floodplain encroachments at all floodplain
crossings except those of the South Fork Catawba River and the Catawba River.
4. The longitudinal floodplain encroachment is along Crowders Creek north of New Haven Drive. The preliminary
engineering designs construction limits encroach on an area approximately 1,400 feet long and 5 acres in size.
As shown in Table 4-14, DSAs 22, 23, and 27 would have the most numbers of bridges
(8 bridges), and DSA 58 would have the least (6 bridges). DSAs 4 and 58 would have the greatest
number of major culverts and pipes (47 culverts and pipes), while DSA 77 would have the fewest
(39 culverts and pipes).
The preliminary engineering designs for all the DSAs would involve floodplain encroachments at
all floodplain crossings except those of the South Fork Catawba River and the Catawba River. At
these locations, the proposed bridges would span both the floodway and the floodplain.
Floodway limits in Gaston County have only been defined for areas within and near municipal
limits within the county. DSAs closer to the municipal limits of Gastonia and Belmont (DSAs 4,
5, and 9) would cross the most numbers of floodways. The preliminary engineering designs for all
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the DSAs propose bridges at all new floodway crossings. These bridges would span the
floodways.
DSAs that are closer to Crowders Creek (DSAs 4, 5, 9, 22, 23, and 27) have the most total
combined floodway and floodplain crossings (21-23 crossings).
The preliminary engineering designs for DSAs that use Corridor Segment J4a (DSAs 4, 5, and 9)
would involve a longitudinal encroachment on the Crowders Creek floodplain just north of New
Haven Drive. This longitudinal encroachment would be approximately 1,400 feet in length and
include an area of approximately 5 acres.
The DSAs for the project have been located in floodplains and/or floodways only in locations
where existing residential and business development and other human and natural environment
constraints have left no reasonable alternatives to the use of floodplains and/or floodways.
Once a Preferred Alternative is selected, a detailed hydrologic and hydraulic analysis will be
performed for each crossing location to determine the actual size and configuration of each
structure. Also, for all new location crossings on FEMA-regulated streams (streams where a
floodway and/or floodplain has been identified), a Conditional Letter of Map Revision (CLOMR)
and Letter of Map Revision (LOMR) will be submitted to the NC Flood Mapping Program for
streams in Gaston County and to Charlotte-Mecklenburg Storm Water Services for streams in
Mecklenburg County.
In NFIP flood hazard areas, the final hydraulic designs for the Preferred Alternative will ensure
that the floodway will carry the 100-year flood without adversely affecting floodplain elevations.
The effect of all the DSAs can be mitigated effectively through proper sizing and design of
hydraulic structures (culverts, bridges, and channel stabilization).
A LOMR is FEMA's modification to an effective FIRM, or Flood Boundary and Floodway Map
(FBFM), or both. LOMRs are generally based upon the implementation of physical measures
affecting the hydrologic or hydraulic characteristics of a flooding source, and thus result in the
modification of the existing regulatory floodway, the effective Base Flood Elevations (BFEs), or
the Special Flood Hazard Area (SFHA). The LOMR officially revises the FIRM or Flood
Boundary and FBFM, and sometimes the Flood Insurance Study (FIS) report, and when
appropriate, includes a description of the modifications (FEMA Web site:
www.fema.gov/plan/prevent/floodplain/nfipkeywords/lomr.shtm).