06-4234. Intent To Prepare an Environmental Impact Statement for the Dam Safety Assurance Evaluation Report, Dover Dam, City of Dover, Tuscarawas County, OH

AGENCY:

Department of the Army, U.S. Army Corps of Engineers, DoD.

ACTION:

Notice of intent.

SUMMARY:

Pursuant to the National Environmental Policy Act (NEPA), the U.S. Army Corps of Engineers (Corps), Huntington District will prepare an Environmental Impact Statement (EIS) to disclose potential impacts to the natural, physical, and human environment resulting from modifications to Dover Dam. This high hazard dam does not conform to current design standards related to stability and sliding during a probable maximum flood. Modifications will be performed so the Dam will meet these standards.

DATES:

A public scoping meeting will be held on May 24, 2006 from 7-8:30 p.m.

ADDRESSES:

Send written comments and suggestions concerning this proposed project to David M. Rieger, PD-R, U.S. Army Corps of Engineers, Huntington District, 502 Eighth Street, Huntington, WV 25701-2070. Telephone: [phone]. Electronic mail: [e-mail]. Requests to be placed on the mailing list should also be sent to this address.

FOR FURTHER INFORMATION CONTACT:

Mr. Rodney Cremeans, U.S. Army Corps of Engineers, Huntington District, 502 Eighth Street, Huntington, WV 25701-2070. Telephone: [phone]. Electronic mail: [e-mail]. mil.

SUPPLEMENTARY INFORMATION:

1. Authority: Investigation and justification of modifications for dam safety assurance to completed Corps of Engineers projects is authorized under Section 1203 of the Water Resources Development Act of 1986 (Pub. L. 99-662).

2. Background: a. Guidance for this study is provided in USACE Engineer Regulation 1110-2-1155 for modifying or developing new facilities, raising the dam and/or improving the stability of the dam to accommodate currently anticipated flood volumes.

b. The Corps evaluates structures such as Dover Dam periodically throughout their life. These evaluations are important for identifying trends in the aging process of the structure as well as offering an opportunity to consider developments in the design and weather forecasting sciences. Concerns for the stability of the dam have grown over the life of Dover Dam. Since the construction of the project in the 1930's, the maximum pool recorded was 907.4 (8.6 feet below the spillway crest) in January 2005. No significant problems have been encountered with the dam, however, inflow is very carefully monitored to ensure the safety of the public downstream of the dam.

c. The Corps will continue to manage stability concerns in the event of extreme flooding. However, recent flood events have highlighted the need to address on-going concerns and renew consideration of potential low-frequency extreme flood events.

d. The National Weather Service has published details of procedures and methods that are used to develop generalized estimates of Probably Maximum Precipitation (PMP), the greatest rainfall rates for specified durations that are theoretically possible for regions throughout the United States. These rainfall estimates are considered extreme, with a very low probability of occurrence. However, the worst-case storms associated with the PMP events, retain some probability of occurrence. These PMP events are used to develop flood scenarios and guide design criteria for strucures such as Dover Dam. The Corps has determined the dam may not safely accommodate flooding during these theoretical probable maximum flood (PMF) events.

e. In the event of a PMF, the pool behind Dover is estimated to reach or exceed elevation 940.5 msl. For context, the project will be completely overtopped at elevations above 931 msl, the current spillway elevation is 916 msl and the project was designed for flood waters reaching only 936.8 msl. The concrete gravity dam is also believed to be unstable against sliding under these conditions due to known faulting and uncertain foundation bedrock quality.

f. The EIS and Evaluation Report will consider the structural integrity of the dam, its ability to accommodate flood waters as well as transportation, noise, terrestrial, aquatic, economic, environmental justice and cultural resource issues associated with the performance of the dam. The EIS and Evaluation Report will recommend any modifications necessary to ensure the long-term safe performance of the structure as originally intended.

g. Modifications to meet current design standards could include raising the dam height, constructing an auxiliary spillway, modifying the existing spillway, constructing a stilling basin downstream of the dam, and anchoring the structure to prevent sliding.

3. Public Participation: a. The Corps of Engineers will conduct a public scoping meeting (see DATES) to gain input from interested agencies, organizations, and the general public concerning the content of the EIS, issues and impacts to be addressed in the EIS, and alternatives that should be analyzed. The meeting will be held at the McDonald/Marlite Conference Center, 143 McDonald Driver Southwest, New Philadelphia, OH. Phone: [phone].

b. The Corps invites full public participation to promote open communication and better decision-making. All persons and organizations that have an interest in the Dover Dam Project or the Muskingum Watershed Conservancy District system of flood damage reduction and the environment are urged to participate in this NEPA evaluation process. Assistance will be provided upon request to anyone having difficulty with learning how to participate.

c. Public comments are welcomed anytime throughout the NEPA process. Formal opportunities for public participation include: (1) Public meetings to be held near the community of Dover; (2) Anytime during the NEPA process via mail, telephone or e-mail; (3) During Review and Comment on the Draft EIS; and (4) Review of the Final EIS. Schedules and locations will be announced in local news media. Interested parties should submit contact information to be included on the mailing list for public distribution of meeting announcements and documents (See ADDRESSES).

4. Schedule: The Draft Environmental Impact Statement is scheduled to be released for public review and comment in September 2006. The Final Report and Final EIS are scheduled to be completed in March 2007.

Brenda S. Bowen,

Army Federal Register Liaison Officer.