Keechelus Dam Safety of Dams Modification, Yakima Project, Washington

AGENCY:

Bureau of Reclamation, Interior.

ACTION:

Notice of intent to prepare an environmental impact statement.

SUMMARY:

Pursuant to section 102(2)(C) of the National Environmental Policy Act (NEPA) of 1969, as amended, the Bureau of Reclamation (Reclamation) proposes to prepare an environmental impact statement (EIS) on structural and nonstructural alternatives to correct safety deficiencies at Keechelus Dam in the State of Washington. In June 1998, Reclamation's Safety of Dams (SOD) Program identified safety deficiencies from void sites and dam embankment deterioration which could lead to embankment failure. The SOD Program indicated that there is a need to correct dam safety deficiencies at Keechelus Dam to protect property and the lives of people living downstream of the dam.

DATES:

Scoping meetings will be held on the following dates and times:

• North Bend, Washington: April 18, 2000, Open House 6 to 7 p.m.; Meeting 7 to 9 p.m.
• Ellensburg, Washington: April 19, Open House 12 noon to 1 p.m.; Meeting 1 to 3 p.m. and Open House 6 to 7 p.m.; Meeting 7 to 9 p.m.

Written comments will be accepted through April 24, 2000, for inclusion in the scoping summary document. Requests for sign language interpretation for the hearing impaired should be submitted to Dave Kaumheimer, as indicated below by April 11, 2000.

ADDRESSES:

Comments and requests to be added to the mailing list may be submitted to Bureau of Reclamation, Upper Columbia Area Office, Attention: Dave Kaumheimer, Environmental Programs Manager, PO Box 1749, Yakima, Washington 98907-1749.

The scoping meetings will be held at the following locations:

• North Bend—North Bend (U.S. Forest Service) Ranger Station, 42404 SE North Bend Way, North Bend, Washington.
• Ellensburg—Ellensburg Inn, 1700 Canyon Road, Ellensburg, Washington.

Our practice is to make comments, including names and home addresses of respondents, available for public review. Individual respondents may request that we withhold their home address from public disclosure, which we will honor to the extent allowable by law. There also may be circumstances in which we would withhold a respondent's identity from public disclosure, as allowed by law. If you wish us to withhold your name and/or address, you must state this prominently at the beginning of your comment. We will make all submissions from organizations or businesses, and from individuals identifying themselves as representatives or officials of organizations or businesses, available for public disclosure in their entirety.

FOR FURTHER INFORMATION CONTACT:

Dave Kaumheimer, Environmental Programs Manager, Bureau of Reclamation, telephone: (509) 575-5848 x232; fax: (509) 454-5650.

The meeting facilities are physically accessible to people with disabilities. Please direct requests for sign language interpretation for the hearing impaired, or other auxiliary aids, to Dave Kaumheimer at (509) 575-5848 x232 via toll free TTY relay (800) 833-6388 by April 11, 2000.

SUPPLEMENTARY INFORMATION:

Background

Keechelus Dam was constructed at the lower end of a natural lake on the Yakima River about 10 miles northwest of Easton, Washington, in Kittitas County. This earthfill structure was constructed between 1913 and 1917 and is approximately 6,550 feet long with a maximum height of 128 feet. It creates a reservoir with an active storage capacity of 158,000 acre-feet.

In June 1998, during the excavation of a trench for a telephone line conduit, a void was found in the crest of Keechelus Dam. This discovery led to further geotechnical investigations, including ground penetrating radar and geologic exploration activities, to determine the condition of the overall dam. Subsequent investigations identified more than 40 potential void sites and significant evidence of dam embankment deterioration from seepage which could lead to embankment failure. As an interim safety measure, Keechelus Reservoir has been operated at a restricted full pool elevation 7 feet below the normal full pool elevation since November 1998, with increased technical monitoring and surveillance at the dam.

The scope of this document will focus on correcting the dam safety deficiencies at Keechelus Dam to protect property and the lives of people living downstream from the dam, and evaluating the potential impacts associated with the proposed alternatives. Correcting the SOD deficiencies in no way restricts potential future modifications to the structure.

Public Involvement

Reclamation plans to conduct public scoping meetings to solicit input on the alternatives developed to correct safety deficiencies at Keechelus Dam and to identify potential issues and impacts associated with those alternatives. Reclamation will summarize comments received during the scoping meetings and from letters of comment received during the scoping period, identified under DATES, into a scoping summary document which will be made available to the public.