[Federal Register Volume 75, Number 24 (Friday, February 5, 2010)]
[Notices]
[Pages 6004-6005]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-2510]


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DEPARTMENT OF DEFENSE

Department of the Army; U.S. Army Corps of Engineers


Notice of Intent To Prepare a Draft Environmental Impact 
Statement and Dam Safety Assurance Program Modification Report for the 
Isabella Dam Project, Kern County, CA

AGENCY: Department of the Army, U.S. Army Corps of Engineers; DOD.

ACTION: Notice of intent.

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SUMMARY: Pursuant to the National Environmental Policy Act of 1969, as 
amended, the U.S. Army Corps of Engineers, Sacramento District (Corps), 
in cooperation with the U.S. Forest Service, Sequoia National Forest, 
intends to prepare a draft Environmental Impact Statement (EIS) for the 
Federal action to remediate seismic, seepage, and hydrologic dam safety 
concerns at the Isabella Lake main and auxiliary dams. Isabella Lake is 
located on the Kern River approximately 45 miles northeast of 
Bakersfield, Kern County, California. The proposed action is being 
conducted through the Corps' Dam Safety Assurance Program (DSAP) for 
the evaluation of existing dams.

ADDRESSES: Current and archival information regarding the Isabella Lake 
DSAP Project can be obtained from the following Web site address: 
http://www.spk.usace.army.mil/projects/civil/Lake_Isabella_Dam/Index.html. Questions or comments regarding the Isabella Lake DSAP 
Project may be submitted through this Web site, or written questions or 
comments can be submitted by mail to Mr. Mitch Stewart, U.S. Army Corps 
of Engineers, Sacramento District, Attn: Planning Division (CESPK-PD-
R), 1325 J Street, Sacramento, CA 95814. Requests to be placed on a 
mailing list may also be submitted through the Web site or to the 
address provided above.

FOR FURTHER INFORMATION CONTACT: Mr. Mitch Stewart at (916) 557-6734, 
e-mail [email protected], or by mail to (see ADDRESSES).

SUPPLEMENTARY INFORMATION: 
    1. Background Information. Based on current engineering knowledge, 
the Corps has determined that the Isabella Lake main and auxiliary dams 
have a high risk of failure due to significant seismic, seepage, and 
hydrologic issues that exist. An external peer review panel, 
commissioned by the Corps, has recently confirmed that the Corps' Class 
I designation ``Urgent and Compelling'' is appropriate for the Isabella 
Lake dams for several reasons:
    a. A possibility of piping along the outlet conduit of its 
auxiliary dam (piping may be defined as fissures or openings through 
which water can travel inside the dam);
    b. Evidence that the auxiliary dam's drain blanket is not 
performing as intended;
    c. Studies find that the Kern Canyon Fault, under the auxiliary 
dam's right abutment, is active;
    d. Evidence that the upper 20 feet of the auxiliary dam's 
foundation is loose

[[Page 6005]]

and might be subject to loss of shear strength during seismic loading;
    e. Hydrologic studies indicate that the spillway is inadequate; and
    f. Extremely high consequences of failure.
    The panel recommended short-term risk reduction measures such as 
maintaining the current reservoir pool restriction elevation of 2,585.5 
feet, 20 feet below normal pool. The panel also recommended long-term 
risk reduction measures including completion of on-going studies of 
major rehabilitation of the auxiliary dam and evaluation of the main 
dam's overall earthquake performance.
    2. Remediation Alternatives. The draft EIS will address an array of 
remediation alternatives that are necessary to prevent loss of life, 
extensive downstream damage, functional loss of the project, and the 
loss of all project benefits. The exact nature and extent of the 
remediation alternatives will be determined based on the results of on-
going geotechnical and engineering studies, public and agency input 
during the scoping period, and preparation of the draft EIS.
    3. Issues To Be Addressed. The draft EIS will address environmental 
issues concerning the remediation alternatives proposed. Issues will be 
identified based on public input during the scoping process and during 
the preparation of the draft EIS. Issues initially identified as 
potentially significant include, but are not limited to: Soils and 
seismicity, hydrology and water quality, noise and vibration, air 
quality, socioeconomics, water supply, land use, recreation, visual and 
aesthetic resources, traffic and transportation, historical and 
cultural resources, vegetation and wildlife, special status species, 
and fisheries.
    4. Public Involvement. Public scoping meetings will be held in May 
2010 at specific locations to be announced within the local Isabella 
Lake DSAP Project area and in Bakersfield, California. The purpose of 
the public scoping meetings will be to present information to the 
public regarding the array of remediation alternatives proposed that 
may be addressed in the draft EIS, receive public comments, and solicit 
input regarding environmental issues of concern to the public. These 
meetings are intended to initiate the process to involve concerned 
individuals, and local, State, and Federal agencies. The public scoping 
meeting place, date, and time will be advertised in advance in local 
newspapers, and meeting announcement letters will be sent to interested 
parties. Written comments may also be submitted via Web site or mail to 
(see ADDRESSES).
    5. Availability of the Draft EIS. The Corps intends to issue the 
draft EIS in May 2011. The Corps will announce availability of the 
draft EIS in the Federal Register and other media, and will provide the 
public, organizations, and agencies with an opportunity to submit 
comments to be addressed in the final EIS.

    Dated: January 26, 2010.
Thomas Chapman,
Commander, Sacramento District, U.S. Army Corps of Engineers.
[FR Doc. 2010-2510 Filed 2-4-10; 8:45 am]
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