United States Section; Notice of Availability of a Final Environmental Assessment and Final Finding of No Significant Impact for Flood Control Improvements to the Arroyo Colorado Floodway, Hidalgo and Cameron Counties, TX, 28952-28954 [E9-14314]
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Federal Register / Vol. 74, No. 116 / Thursday, June 18, 2009 / Notices
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Authority: The authority for this action is
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Dated: June 9, 2009.
Marvin Moriarty,
Acting Director, Fish and Wildlife Service.
[FR Doc. E9–14346 Filed 6–17–09; 8:45 am]
BILLING CODE 4310–55–P
INTERNATIONAL BOUNDARY AND
WATER COMMISSION
United States Section; Notice of
Availability of a Final Environmental
Assessment and Final Finding of No
Significant Impact for Flood Control
Improvements to the Arroyo Colorado
Floodway, Hidalgo and Cameron
Counties, TX
AGENCY: United States Section,
International Boundary and Water
Commission, United States and Mexico.
ACTION: Notice of Availability of Final
Environmental Assessment (EA) and
Final Finding of No Significant Impact
(FONSI).
SUMMARY: Pursuant to Section 102(2)(c)
of the National Environmental Policy
Act (NEPA) of 1969 (42 U.S.C. 4321 et
seq.), the Council on Environmental
Quality Final Regulations (40 CFR Parts
1500 through 1508), and the United
States Section, International Boundary
and Water Commission’s (USIBWC)
Operational Procedures for
Implementing Section 102 of NEPA,
published in the Federal Register
September 2, 1981 (46 FR 44083); the
USIBWC hereby gives notice of
availability of the Final Environmental
Assessment and FONSI for Flood
Control Improvements to the Arroyo
Colorado Floodway, a component of the
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Federal Register / Vol. 74, No. 116 / Thursday, June 18, 2009 / Notices
interior floodways system of the Lower
Rio Grande Flood Control Project.
FOR FURTHER INFORMATION CONTACT: Rita
Crites, Environmental Protection
Specialist, Environmental Management
Division, United States Section,
International Boundary and Water
Commission; 4171 N. Mesa, C–100; El
Paso, Texas 79902. Telephone: (915)
832–4781; e-mail: ritacrites@ibwc.gov.
DATES: The Final EA and FONSI will be
available June 11, 2009.
SUPPLEMENTARY INFORMATION:
Background
The Arroyo Colorado is an ancient
distributary of the Rio Grande, and it
serves as drainage for crop irrigation,
municipal wastewater returns, and as a
floodway during periods of heavy
precipitation in the Lower Rio Grande
Valley. The project area includes two
segments of the flood control levee
system with a combined length of 11
miles.
The USIBWC prepared this EA for the
proposed action to increase flood
control of the Arroyo Colorado Levee
System by raising the elevation of these
two levee segments for improved flood
protection.
The beginning of this project is a 2.1
mile Divisor Dike near the juncture
point of the Arroyo Colorado and the
North Floodway in Hidalgo County,
extending a total of 6.9 miles to the
Willacy Canal. The remaining segment
is 4.0 miles from the Willacy Canal
ending at White Ranch Road in
Cameron County, Texas.
Proposed Action
The proposed levee rehabilitation
improvements consist of: (1) Raising the
top-of-levee elevation, (2) conducting
geotechnical investigations and testing
to determine the type and extent of any
required remediation improvements due
to slope stability, seepage, levee
settlement, and any other geotechnical
issues that may cause levee failure; and
(3) modifying, if necessary, hardware or
structures located along the levee
reaches. Any modifications will be in
compliance with the Texas Historical
Commission recommendations. The top
elevation of the levee-raising
improvements will be to provide
containment of flood flows with a
minimum freeboard of 3 feet for water
surface elevations as calculated in the
USIBWC 2003 Hydraulic Model for the
LRGFCP. A centered levee expansion is
assumed for most areas of the Arroyo
Colorado Levee system, except south of
La Feria reservoir, where levee
expansion will be offset to the riverside
of the existing levee.
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The proposed action will increase the
height of the levee up to 2 feet for
approximately 8.6 percent of the 11mile segment. Approximately 4 percent
of the levee segment will be increased
from 2 to 4 feet, and approximately 2.4
percent will be increased from 4 to 6
feet. The existing levee is a raised
trapezoidal compacted-earth structure
with a crown width of 16 feet, a typical
height ranging from 10 to 15 feet, and
approximately 3:1 side slope ratio
(horizontal run: vertical rise). For a
typical levee cross-section at the ACF
that requires additional fill material to
the crown the levee footprint would be
expanded at a 1:6 ratio (crown height:
footprint length). The footprint
expansion would be equally divided
between the riverside and landside
(centered expansion) or entirely on one
side (offset expansion). Moderately
higher increases will be needed in a
small segment that accounts for less
than 1.2 percent of the total length. In
areas where existing topography is too
steep to allow levee expansion,
construction solutions, including
armored banks (riprap) or retaining
walls, will be used. Excavation outside
the existing right-of-way is not
anticipated.
The EA assesses potential
environmental impacts of the proposed
action and the no action alternative.
Potential impacts on natural, cultural,
and other resources were evaluated, and
mitigation measures were incorporated
into the proposed action. A Finding of
No Significant Impact was issued for the
proposed action based on a review of
the facts and analyses contained in the
EA.
28953
alternative will retain the current
configuration of the ACF levee system,
with no impacts to biological and
cultural resources, water resources, land
use, soil, community resources, or
environmental health issues. In terms of
flood protection, however, current
containment capacity under the no
action alternative may be insufficient to
fully control Rio Grande flooding under
severe storm events, including
associated risks to personal safety and
property. The levee system will not
meet FEMA requirements for levee
system certification.
Proposed Action
Biological Resources
Levee System Evaluation
Biological resources in the vicinity of
the levee systems are dominated by
agricultural fields, rangelands, and nonnative grasslands. There are some
woody species along the margins of the
Arroyo Colorado, drainage ditches from
irrigation fields, and adjacent to borrow
pits. The 160-foot wide biological
survey corridor, centered on the existing
levee, includes approximately 221 acres,
primarily composed of non-native
grasslands dominated by buffelgrass and
king ranch bluestem.
The proposed action will raise the
levee using a centered expansion,
except in areas south of La Feria
reservoir, where an offset expansion
will be utilized. The proposed levee
expansion will remove non-native
grasslands on the levee slopes and
adjacent areas. Native grasses will be
planted immediately after the
completion of the project, and the levee
expansion will not occur in wooded
areas. Less than one-half acre of nonjurisdictional wetlands will be affected,
but no jurisdictional wetlands will be
affected by the levee expansion. No
habitats used by federally or state-listed
threatened or endangered species will
be impacted by the levee expansion.
In areas adjacent to sensitive areas
such as water bodies, levee expansion
may be altered to an offset expansion
toward the riverside of the levee to
avoid impacting sensitive resources. In
areas where the existing topography is
too steep to allow levee expansion,
construction solutions, including
armored banks, will prevent erosion of
the levee slopes. The construction
solutions will not affect sensitive
habitats, including wooded areas,
habitats for threatened and endangered
species, or jurisdictional wetlands.
No Action Alternative
Cultural Resources
The no action alternative was
evaluated as the single alternative action
to the proposed action. The no action
Improvements to the ACF levee
system may adversely affect prehistoric
and historic archaeological resources.
Summary of Findings
Pursuant to the National
Environmental Policy Act (NEPA)
guidance (40 CFR 1500–1508), The
President’s Council on Environmental
Quality issued regulations for
implementing NEPA, which included
provisions for both the content and
procedural aspects of the required EA.
The USIBWC completed an EA of the
potential environmental consequences
of raising the Arroyo Colorado
Floodway (ACF) levee system to meet
current requirements for flood control.
The EA, which supports this Finding of
No Significant Impact, evaluated the
proposed action and no action
alternative.
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28954
Federal Register / Vol. 74, No. 116 / Thursday, June 18, 2009 / Notices
Some areas adjacent to the toe of the
levee contain intact archaeological
resources. Adverse effects to
archaeological resources may occur
from the use of heavy equipment during
levee construction that could disturb
surface or shallowly buried deposits.
Adverse effects may also occur to
archaeological deposits that will be
buried by the addition of the fill
material on the surface above them.
Alternatively, levee footprint expansion
may protect archaeological resources by
capping with fill material, preserving
those resources in place.
Architectural resources may be
adversely affected by levee height
increases or by expansion of the levee
footprint. Potential effects include
vibration and ground disturbance from
the use of heavy equipment during
construction. Design for levee
improvements is primarily considering
avoidance of the structures as much as
possible. However, if structures have to
be removed or modified, USIBWC will
consult with the Texas Historical
Commission (THC) to determine the
appropriate level of documentation
prior to any modification. In addition to
documentation, mitigation of impacts to
cultural resources may include their
replacement with ‘‘in-kind’’ structures
that will look and operate the same.
Native American resources may be
affected by the levee improvements;
consultation with the Native American
tribes is ongoing to identify resources or
concerns regarding the project.
Under NEPA, there will be no
significant impacts (i.e., ‘‘unresolvable’’
adverse effects under National Historic
Preservation Act [NHPA]) to cultural
resources because all cultural resources
will be identified and evaluated for
National Register of Historic Places
(NRHP) eligibility. Any impacts to
National Register of Historic Placeseligible resources will be mitigated prior
to implementation of levee height
increases or footprint expansion, in
consultation with the Texas Historical
Commission and Native American
Tribes.
Water Resources
Flood control improvements to the
ACF will increase flood containment
capacity to control the design flood
event with a negligible increase in water
surface elevation. Levee footprint
expansion will not affect water bodies.
Land Use
Footprint levee expansion, where
required, will take place completely
within the existing ROW. No urban or
agricultural lands will be affected.
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Soil
Improvement activity contributing to
soil disturbance will include
geotechnical investigations and adding
soil to the top and sides of the levee.
Levee fill material will come from local
commercial sources and not from
borrow areas in the floodplain. The
disturbance of soil will occur within
areas where soil has been disturbed and
modified by prior levee construction
and maintenance activities. Therefore,
alteration of soil previously
unassociated with the existing levee
will not occur.
Community Resources
In terms of socioeconomic resources,
the influx of federal funds into Hidalgo
and Cameron Counties from the flood
control improvement area will have a
positive but minor local economic
impact. The impact will be limited to
the construction period, and represent
less than 1 percent of the annual county
employment, income, and sales values.
No adverse impacts to
disproportionately high minority and
low-income populations were identified
for construction activities. Moderate
utilization of public roads will be
required during construction; a
temporary increase in access road use
will be required for equipment
mobilization to staging areas.
Environmental Health Issues
Estimated air emissions of five criteria
pollutants during construction will be
discontinuous and represent less than
0.13 percent of the annual emissions
inventory within the air quality control
region of Hidalgo, Cameron, and
Willacy Counties. There will be a
moderate increase in ambient noise
levels due to construction activities. No
long-term and regular exposure is
expected above noise threshold values.
A database search indicated that no
waste storage and disposal sites were
within the proposed ACF levee
improvement area, and none will affect,
or be affected by, the levee improvement
project.
Best Management Practices
When warranted due to engineering
considerations, or for protection of
biological or cultural resources, the
need for levee footprint expansion will
be eliminated by levee slope adjustment
or use of retaining walls or armored
banks. Best management practices
during construction will include
development of a storm water pollution
prevention plan to avoid impacts to
receiving waters, and use of sediment
barriers and soil wetting to minimize
erosion.
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To protect vegetation cover, the
embankment improvement areas will be
re-vegetated with native herbaceous
species. To protect wildlife,
construction activities will be scheduled
to occur, to the extent possible, outside
the March to August bird migratory
season.
Availability
Single hard copies of the Final
Environmental Assessment and Finding
of No Significant Impact may be
obtained by request at the above contact
information. Electronic copies may also
be obtained from the USIBWC Home
Page at https://www.ibwc.gov/
Organization/Environmental/
reports_studies.html.
Dated: June 12, 2009.
Robert McCarthy,
General Counsel.
[FR Doc. E9–14314 Filed 6–17–09; 8:45 am]
BILLING CODE 7010–01–P
DEPARTMENT OF JUSTICE
Notice of Lodging of Consent Decree
Under the Comprehensive
Environmental Response,
Compensation, and Liability Act
Notice is hereby given that on June 3,
2009, a proposed Consent Decree in
United States v. General Electric Co.,
Civil Action No. 1:09–cv–00545, was
lodged with the United States District
Court for the District of New Mexico.
The Consent Decree resolves the
United States’ claims against General
Electric Company (‘‘GE’’) at the South
Valley Superfund Site located in
Albuquerque, New Mexico. Those
claims were brought under Section 107
of the Comprehensive Environmental
Response, Compensation and Liability
Act, 42 U.S.C. 107. The Site consists of
several industrial facilities, including an
aircraft manufacturing plant currently
owned and/or operated by GE and
formerly owned and/or operated by the
United States Air Force (‘‘USAF’’), the
United States Department of Energy
(‘‘DOE’’), and others.
The Consent Decree requires that GE
pay a lump sum of $257,670.00 to
reimburse the United States for past
response costs, a lump sum of $71,715
toward the United States’ future
response costs, and interest accrued on
these two sums during the period from
November 1, 2002 to the date of entry
of the Consent Decree. The Consent
Decree also memorializes the obligation
of the USAF and DOE to pay a lump
sum of $2,605,330.00 in reimbursement
for past response costs and a lump sum
E:\FR\FM\18JNN1.SGM
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]]>Agencies
[Federal Register Volume 74, Number 116 (Thursday, June 18, 2009)]
[Notices]
[Pages 28952-28954]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-14314]
=======================================================================
-----------------------------------------------------------------------
INTERNATIONAL BOUNDARY AND WATER COMMISSION
United States Section; Notice of Availability of a Final
Environmental Assessment and Final Finding of No Significant Impact for
Flood Control Improvements to the Arroyo Colorado Floodway, Hidalgo and
Cameron Counties, TX
AGENCY: United States Section, International Boundary and Water
Commission, United States and Mexico.
ACTION: Notice of Availability of Final Environmental Assessment (EA)
and Final Finding of No Significant Impact (FONSI).
-----------------------------------------------------------------------
SUMMARY: Pursuant to Section 102(2)(c) of the National Environmental
Policy Act (NEPA) of 1969 (42 U.S.C. 4321 et seq.), the Council on
Environmental Quality Final Regulations (40 CFR Parts 1500 through
1508), and the United States Section, International Boundary and Water
Commission's (USIBWC) Operational Procedures for Implementing Section
102 of NEPA, published in the Federal Register September 2, 1981 (46 FR
44083); the USIBWC hereby gives notice of availability of the Final
Environmental Assessment and FONSI for Flood Control Improvements to
the Arroyo Colorado Floodway, a component of the
[[Page 28953]]
interior floodways system of the Lower Rio Grande Flood Control
Project.
FOR FURTHER INFORMATION CONTACT: Rita Crites, Environmental Protection
Specialist, Environmental Management Division, United States Section,
International Boundary and Water Commission; 4171 N. Mesa, C-100; El
Paso, Texas 79902. Telephone: (915) 832-4781; e-mail:
ritacrites@ibwc.gov.
DATES: The Final EA and FONSI will be available June 11, 2009.
SUPPLEMENTARY INFORMATION:
Background
The Arroyo Colorado is an ancient distributary of the Rio Grande,
and it serves as drainage for crop irrigation, municipal wastewater
returns, and as a floodway during periods of heavy precipitation in the
Lower Rio Grande Valley. The project area includes two segments of the
flood control levee system with a combined length of 11 miles.
The USIBWC prepared this EA for the proposed action to increase
flood control of the Arroyo Colorado Levee System by raising the
elevation of these two levee segments for improved flood protection.
The beginning of this project is a 2.1 mile Divisor Dike near the
juncture point of the Arroyo Colorado and the North Floodway in Hidalgo
County, extending a total of 6.9 miles to the Willacy Canal. The
remaining segment is 4.0 miles from the Willacy Canal ending at White
Ranch Road in Cameron County, Texas.
Proposed Action
The proposed levee rehabilitation improvements consist of: (1)
Raising the top-of-levee elevation, (2) conducting geotechnical
investigations and testing to determine the type and extent of any
required remediation improvements due to slope stability, seepage,
levee settlement, and any other geotechnical issues that may cause
levee failure; and (3) modifying, if necessary, hardware or structures
located along the levee reaches. Any modifications will be in
compliance with the Texas Historical Commission recommendations. The
top elevation of the levee-raising improvements will be to provide
containment of flood flows with a minimum freeboard of 3 feet for water
surface elevations as calculated in the USIBWC 2003 Hydraulic Model for
the LRGFCP. A centered levee expansion is assumed for most areas of the
Arroyo Colorado Levee system, except south of La Feria reservoir, where
levee expansion will be offset to the riverside of the existing levee.
The proposed action will increase the height of the levee up to 2
feet for approximately 8.6 percent of the 11-mile segment.
Approximately 4 percent of the levee segment will be increased from 2
to 4 feet, and approximately 2.4 percent will be increased from 4 to 6
feet. The existing levee is a raised trapezoidal compacted-earth
structure with a crown width of 16 feet, a typical height ranging from
10 to 15 feet, and approximately 3:1 side slope ratio (horizontal run:
vertical rise). For a typical levee cross-section at the ACF that
requires additional fill material to the crown the levee footprint
would be expanded at a 1:6 ratio (crown height: footprint length). The
footprint expansion would be equally divided between the riverside and
landside (centered expansion) or entirely on one side (offset
expansion). Moderately higher increases will be needed in a small
segment that accounts for less than 1.2 percent of the total length. In
areas where existing topography is too steep to allow levee expansion,
construction solutions, including armored banks (riprap) or retaining
walls, will be used. Excavation outside the existing right-of-way is
not anticipated.
The EA assesses potential environmental impacts of the proposed
action and the no action alternative. Potential impacts on natural,
cultural, and other resources were evaluated, and mitigation measures
were incorporated into the proposed action. A Finding of No Significant
Impact was issued for the proposed action based on a review of the
facts and analyses contained in the EA.
Summary of Findings
Pursuant to the National Environmental Policy Act (NEPA) guidance
(40 CFR 1500-1508), The President's Council on Environmental Quality
issued regulations for implementing NEPA, which included provisions for
both the content and procedural aspects of the required EA. The USIBWC
completed an EA of the potential environmental consequences of raising
the Arroyo Colorado Floodway (ACF) levee system to meet current
requirements for flood control. The EA, which supports this Finding of
No Significant Impact, evaluated the proposed action and no action
alternative.
Levee System Evaluation
No Action Alternative
The no action alternative was evaluated as the single alternative
action to the proposed action. The no action alternative will retain
the current configuration of the ACF levee system, with no impacts to
biological and cultural resources, water resources, land use, soil,
community resources, or environmental health issues. In terms of flood
protection, however, current containment capacity under the no action
alternative may be insufficient to fully control Rio Grande flooding
under severe storm events, including associated risks to personal
safety and property. The levee system will not meet FEMA requirements
for levee system certification.
Proposed Action
Biological Resources
Biological resources in the vicinity of the levee systems are
dominated by agricultural fields, rangelands, and non-native
grasslands. There are some woody species along the margins of the
Arroyo Colorado, drainage ditches from irrigation fields, and adjacent
to borrow pits. The 160-foot wide biological survey corridor, centered
on the existing levee, includes approximately 221 acres, primarily
composed of non-native grasslands dominated by buffelgrass and king
ranch bluestem.
The proposed action will raise the levee using a centered
expansion, except in areas south of La Feria reservoir, where an offset
expansion will be utilized. The proposed levee expansion will remove
non-native grasslands on the levee slopes and adjacent areas. Native
grasses will be planted immediately after the completion of the
project, and the levee expansion will not occur in wooded areas. Less
than one-half acre of non-jurisdictional wetlands will be affected, but
no jurisdictional wetlands will be affected by the levee expansion. No
habitats used by federally or state-listed threatened or endangered
species will be impacted by the levee expansion.
In areas adjacent to sensitive areas such as water bodies, levee
expansion may be altered to an offset expansion toward the riverside of
the levee to avoid impacting sensitive resources. In areas where the
existing topography is too steep to allow levee expansion, construction
solutions, including armored banks, will prevent erosion of the levee
slopes. The construction solutions will not affect sensitive habitats,
including wooded areas, habitats for threatened and endangered species,
or jurisdictional wetlands.
Cultural Resources
Improvements to the ACF levee system may adversely affect
prehistoric and historic archaeological resources.
[[Page 28954]]
Some areas adjacent to the toe of the levee contain intact
archaeological resources. Adverse effects to archaeological resources
may occur from the use of heavy equipment during levee construction
that could disturb surface or shallowly buried deposits. Adverse
effects may also occur to archaeological deposits that will be buried
by the addition of the fill material on the surface above them.
Alternatively, levee footprint expansion may protect archaeological
resources by capping with fill material, preserving those resources in
place.
Architectural resources may be adversely affected by levee height
increases or by expansion of the levee footprint. Potential effects
include vibration and ground disturbance from the use of heavy
equipment during construction. Design for levee improvements is
primarily considering avoidance of the structures as much as possible.
However, if structures have to be removed or modified, USIBWC will
consult with the Texas Historical Commission (THC) to determine the
appropriate level of documentation prior to any modification. In
addition to documentation, mitigation of impacts to cultural resources
may include their replacement with ``in-kind'' structures that will
look and operate the same.
Native American resources may be affected by the levee
improvements; consultation with the Native American tribes is ongoing
to identify resources or concerns regarding the project.
Under NEPA, there will be no significant impacts (i.e.,
``unresolvable'' adverse effects under National Historic Preservation
Act [NHPA]) to cultural resources because all cultural resources will
be identified and evaluated for National Register of Historic Places
(NRHP) eligibility. Any impacts to National Register of Historic
Places-eligible resources will be mitigated prior to implementation of
levee height increases or footprint expansion, in consultation with the
Texas Historical Commission and Native American Tribes.
Water Resources
Flood control improvements to the ACF will increase flood
containment capacity to control the design flood event with a
negligible increase in water surface elevation. Levee footprint
expansion will not affect water bodies.
Land Use
Footprint levee expansion, where required, will take place
completely within the existing ROW. No urban or agricultural lands will
be affected.
Soil
Improvement activity contributing to soil disturbance will include
geotechnical investigations and adding soil to the top and sides of the
levee. Levee fill material will come from local commercial sources and
not from borrow areas in the floodplain. The disturbance of soil will
occur within areas where soil has been disturbed and modified by prior
levee construction and maintenance activities. Therefore, alteration of
soil previously unassociated with the existing levee will not occur.
Community Resources
In terms of socioeconomic resources, the influx of federal funds
into Hidalgo and Cameron Counties from the flood control improvement
area will have a positive but minor local economic impact. The impact
will be limited to the construction period, and represent less than 1
percent of the annual county employment, income, and sales values. No
adverse impacts to disproportionately high minority and low-income
populations were identified for construction activities. Moderate
utilization of public roads will be required during construction; a
temporary increase in access road use will be required for equipment
mobilization to staging areas.
Environmental Health Issues
Estimated air emissions of five criteria pollutants during
construction will be discontinuous and represent less than 0.13 percent
of the annual emissions inventory within the air quality control region
of Hidalgo, Cameron, and Willacy Counties. There will be a moderate
increase in ambient noise levels due to construction activities. No
long-term and regular exposure is expected above noise threshold
values. A database search indicated that no waste storage and disposal
sites were within the proposed ACF levee improvement area, and none
will affect, or be affected by, the levee improvement project.
Best Management Practices
When warranted due to engineering considerations, or for protection
of biological or cultural resources, the need for levee footprint
expansion will be eliminated by levee slope adjustment or use of
retaining walls or armored banks. Best management practices during
construction will include development of a storm water pollution
prevention plan to avoid impacts to receiving waters, and use of
sediment barriers and soil wetting to minimize erosion.
To protect vegetation cover, the embankment improvement areas will
be re-vegetated with native herbaceous species. To protect wildlife,
construction activities will be scheduled to occur, to the extent
possible, outside the March to August bird migratory season.
Availability
Single hard copies of the Final Environmental Assessment and
Finding of No Significant Impact may be obtained by request at the
above contact information. Electronic copies may also be obtained from
the USIBWC Home Page at https://www.ibwc.gov/Organization/Environmental/reports_studies.html.
Dated: June 12, 2009.
Robert McCarthy,
General Counsel.
[FR Doc. E9-14314 Filed 6-17-09; 8:45 am]
BILLING CODE 7010-01-P
