Modification and Construction of Transmission Lines for the U.S. 93 Hoover Dam Bypass Project (DOE/EIS-0352)

DEPARTMENT OF ENERGY

Western Area Power Administration

Modification and Construction of Transmission Lines for the U.S.

93 Hoover Dam Bypass Project (DOE/EIS-0352)

AGENCY: Western Area Power Administration, DOE.

ACTION: Record of Decision.

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SUMMARY: The Federal Highway Administration (FHWA) prepared an

Environmental Impact Statement (EIS) for construction of a new segment

of U.S. Highway 93 for the purpose of improving congestion and

hazardous vehicle/pedestrian conflicts where the highway crosses the

Colorado River over Hoover Dam. As a cooperating agency for the EIS,

Western Area Power Administration (Western) proposed modifications to

its transmission system and facilities to accommodate the construction

of the new highway and bridge spanning the Colorado River. With this

Record of Decision (ROD), Western is adopting the FHWA EIS and

announcing its decision to modify its transmission system to

accommodate the new highway segment. Western's decision for its action

considered the environmental ramifications of the U.S. 93 Hoover Dam

Bypass Project (Project). Western will ensure that its responsibilities

under the National Historic Preservation Act (NHPA) and the Endangered

Species Act (ESA) are met before the modifications are implemented.

FOR FURTHER INFORMATION CONTACT: Mr. John Holt, Environment Manager,

Desert Southwest Customer Service Region, Western Area Power

Administration, P.O. Box 6457, Phoenix, AZ 85005, telephone (602) 352-

2592, e-mail [email protected]. Copies of the EIS and the FHWA ROD are

available from Dave Zanetell, Project Manager, Federal Highway

Administration, 555 Zang Street, HFL-16, Lakewood, CO 80228, telephone

(303) 716-2157. For information about the Department of Energy (DOE)

National Environmental Policy Act (NEPA) process, contact Ms. Carol M.

Borgstrom, Director, NEPA Policy and Compliance, EH-42, U.S. Department

of Energy, 1000 Independence Avenue SW., Washington, DC 20585,

telephone (202) 586-4600 or (800) 472-2756.

SUPPLEMENTARY INFORMATION: FHWA was the lead agency for the Project EIS

(FHWA-AZNV-EIS-98-03-01; Final dated January 2001). Western was

designated a cooperating agency for the Project EIS by the FHWA on

November 27, 1998. After an independent review of the Final FHWA EIS,

Western concluded that its comments and suggestions have been satisfied

and with this notice, is adopting the FHWA EIS for its participation in

the Project. Western's EIS number is DOE/EIS-0352.

The FHWA released its ROD on the Project in March 2001 and selected

the Sugarloaf Mountain route as its preferred alternative. The

Sugarloaf Mountain Alternative consists of construction of a new bridge

and highway access across the Colorado River in the vicinity of Hoover

Dam. The new bridge and highway will eliminate truck traffic and other

through-traffic over Hoover Dam. The Project is located in Clark

County, Nevada, and Mohave County, Arizona, and lies entirely on

Federal lands, including the Lake Mead National Recreation Area

(administered by the

[[Page 61620]]

National Park Service) and the Hoover Dam Reservation Area

(administered by the U.S. Bureau of Reclamation). The Sugarloaf

Mountain Alternative crosses the Colorado River about 1,500 feet

downstream from Hoover Dam and requires construction of approximately

2.2 miles of highway approach in Nevada, a 1,700-foot-long bridge, and

a 1.1-mile highway approach in Arizona. The EIS addresses the effects

of the Project, including modification of Western's transmission

system.

Western has decided to modify the current transmission system

configuration including substation terminal work, and remove the

Arizona and Nevada (A&N) Switchyard to accommodate the new highway

segment and bridge. Modifications to Western's transmission system will

occur in two phases. The modifications for the first phase include: (a)

Rebuilding approximately 2.6 (total) miles of the Hoover-Mead No. 6

(single circuit) and No. 7 (double circuit) 230-kilovolt (kV)

Transmission Lines (removing electrical equipment, conductors, overhead

ground wires; replacing lattice steel structures with steel poles; and

installing conductors, overhead ground wire, insulators, and

miscellaneous transmission line hardware); (b) Removing conductors and

overhead ground wires and insulator assemblies for approximately 1.2

(total) miles of the existing Arizona-Nevada Circuits 11 and 12 230-kV

Transmission Lines between the Hoover Dam to the A&N Switchyard; (c)

Constructing approximately 0.3 miles of single circuit 230-kV

transmission line connecting Southern California Edison Circuit No. 10

to the A&N Switchyard and to the Hoover Dam Power Plant; and (d)

Modifying transmission line connections at the Hoover Dam Power Plant

yard and A&N Switchyard to accommodate the new configurations. Terminal

work will include replacing surge arresters and associated steel

supports. Other first phase modifications may be required based on

final design. Phase one would be complete by spring 2003.

Modifications for the second phase include the removal of the A&N

Switchyard and the upgrade of the Hoover-Mead transmission line. The

impacts of the removal of the A&N Switchyard were evaluated as part of

the EIS. The removal of the A&N Switchyard will dictate upgrades to

existing transmission lines that connect at the switchyard and run to

the Mead substation (Hoover-Mead Transmission Line Upgrade). The need

for this transmission line upgrade was part of the transmission

reconfiguration options evaluated in the Final EIS, but since the final

configuration was dependent upon the FHWA's decision, this upgrade was

not fully evaluated in the EIS. Phase two is scheduled for completion

in spring 2004.

The FHWA determined that the Sugarloaf Mountain Alternative is the

environmentally preferable alternative and evaluated the social,

economic, and environmental impacts to the affected area in the EIS.

Where the impact from Western's action was addressed as a subset of the

overall Project impacts, the EIS serves as Western's environmental

review. For the Hoover-Mead Transmission Line Upgrade, where the

impacts from Western's action were not addressed pending final Project

design, Western will prepare a separate Environmental Assessment (EA).

Western will complete the EA, including cultural and endangered species

consultations, prior to its implementation.

The EIS impact analysis concluded that, with mitigation measures,

most impacts from the Project would not be significant. There would be

significant unavoidable visual impacts to several historic properties

and Traditional Cultural Properties (TCPs), including the Hoover Dam

National Historic Landmark and the Gold Strike Canyon and Sugarloaf

Mountain TCPs. Other historic sites or features would be affected or

potentially affected by the Project, including some elements of the

transmission system not owned by Western (the Nevada State Switchyard,

the Metropolitan Water District Switchyard, and the Southern California

Edison Switchyard), as well as the transmission towers and lines in

Arizona and Nevada and the A&N Switchyard that would be affected by

Western's action. The FHWA has consulted with the State Historic

Preservation Office, the Advisory Council on Historic Preservation and

Native American tribes. A Programmatic Agreement (PA) and treatment

plan was developed for avoidance, minimization, and mitigation of

adverse effects to historical and cultural properties. Western is a

signatory to the PA. The FHWA is required to complete historic

documentation of facilities affected by the Project as described in the

PA. Western will ensure that its responsibilities under the NHPA are

met before its action is implemented.

There will be no air, noise, land use, or socioeconomic impacts

stemming from phase one of Western's action. For the Project as a

whole, there will be no long-term impacts to air quality. Noise levels

would be elevated during construction due to construction traffic and

blasting. Some recreational activities would be restricted during

construction for safety purposes, but there are no long-term impacts to

the general uses of the area. Since the Project area is located in a

currently unpopulated area, no minority or low-income groups live in

the area; therefore, no disproportionately high and adverse human

health or environmental effects on minority and low-income groups is

anticipated.

The U.S. Fish and Wildlife Service issued a Biological Opinion for

the Project, which determined that the Project is not likely to

adversely affect the bald eagle (Haliaeetus leucocephalus), razorback

sucker (Xyrauchen texanus), southwestern willow flycatcher (Empodonax

traillii extimus), bonytail chub (Gila elegans), or Devil's Hole

pupfish (Cyprinodon diabolis), which are federally listed endangered

species. The Sugarloaf Mountain Alternative may affect the desert

tortoise, a Federally-listed threatened species. The Biological Opinion

provides mitigation to avoid harm to the desert tortoise. Western will

ensure that its responsibilities under the ESA are met before the

transmission line modifications are implemented.

Other species of concern affected by the Project include the desert

bighorn sheep (Ovis canidensis nelsoni), banded Gila monster (Heloderma

suspectum cinctum), Yuma puma (mountain lion) (Felis concolor growni),

and bicolored penstemon (Penstemon bicolor ssp. roseus). Western is

adopting the mitigation measures in the Final EIS and the terms and

conditions identified in the FHWA Biological Opinion for reducing

impacts to these species.

While the Colorado River itself is in an area subject to flooding,

the Project area is considered to be in an area of minimal or moderate

risk of flooding. There are no wetlands in the Project area.

Construction impacts to water quality will primarily be from runoff

from new cut and fill slopes and construction roads. Western

construction activities may impact water quality; therefore, it is

adopting mitigation measures specified in the EIS to minimize these

impacts.

The A&N Switchyard will be removed as part of Western's phase two

action. The site may contain soil contaminated with polychlorinated

biphenyls (PCBs). Prior to any construction activities, contaminated

soil will be identified, removed, and properly disposed of in

accordance with the Resource Conservation and Recovery Act, and other

applicable or relevant and appropriate requirements.

[[Page 61621]]

Description of Alternatives

Construction of the FHWA preferred alternative will require removal

and modification of Western's transmission system. Western evaluated

seven preliminary electrical transmission reconfiguration options as

part of the EIS. All options require removal of existing spans and

towers and construction of new spans. Three of the options would

require removal of the existing A&N Switchyard and replacing a single-

phase circuit with a double-phase circuit to the Mead Substation (phase

two). Additionally, the Sugarloaf Mountain Alternative requires a

realignment of two of the Hoover-Mead transmission lines to accommodate

the new highway alignment.

Western determined the best engineering approach for the phase one

and two modifications discussed above based on an evaluation of the

electrical conditions on the transmission lines and switchyards and

current transmission line construction and electrical standards.

The No Action Alternative was evaluated in the EIS and found to not

meet the Project purpose and need.

Mitigation Measures

The Final EIS identified mitigation measures needed to reduce the

impacts of the Project. The specific measures are discussed in the FHWA

ROD on pages 22 to 35 and in Chapter 3 of the EIS. Western is adopting

those measures that are applicable to its action and will issue a

Mitigation Action Plan (MAP) prior to any construction activities that

will address the adopted and standard mitigation measures. Some of the

measures include restricting vehicular traffic to existing access roads

or public roads, recontouring and reseeding disturbed areas,

environmental awareness training for all construction and supervisory

personnel, and mitigation of radio and television interference

generated by transmission lines. Long-term operations of the

transmission line will follow Western's standard operating procedures

and will not be affected by this action. The mitigation that applies to

the construction of the new lines and the upgrading of the existing

lines includes the following provisions:

1. Protection of the desert tortoise and banded Gila monster

through compliance with the FHWA Biological Opinion.

2. Protection of Cultural and Historical resources as signators to

the Programmatic Agreement.

3. Adoption of mitigation measures as specified in the FWHA EIS.

4. Monitor actions for compliance with Western's standard

mitigation measures.

This ROD has been prepared in accordance with Council on

Environmental Quality regulations for implementing NEPA (40 CFR parts

1500-1508) and DOE Procedures for Implementing NEPA (10 CFR part 1021).

Upon approval, the MAP will be made available.

Dated: September 20, 2002.

Michael S. Hacskaylo,

Administrator.

[FR Doc. 02-24862 Filed 9-30-02; 8:45 am]

BILLING CODE 6450-01-P