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AmerenUE Proposes to Implement Safety Stabilization Plan at its Taum Sauk Plant
As required by the Federal Energy Regulatory Commission, AmerenUE has developed a work plan for safely stabilizing the upper reservoir at its Taum Sauk Plant near Lesterville, MO.

The FERC has instructed AmerenUE to proceed with its Safety Stabilization Plan. In response, AmerenUE filed a request with the Missouri Department of Natural Resources for a permit to implement the plan.

The plan specifies the work necessary to safely stabilize the Taum Sauk Plants upper reservoir, following the Dec. 14, 2005, breach in the northwest corner. On Dec. 14, a 700-foot rupture in the upper reservoir of the 40-year-old hydroelectric plant caused more than one billion gallons of water to flood the Johnsons Shut-Ins State Park near Lesterville.

Slated for completion by summer 2006, the safety initiative also includes phased-in projects for:

Establishing safe slopes in the breached area and establishing a safe working area along the top of the dike.

Removing concrete parapet wall panels at the top of the dike to allow access there by equipment used to stabilize the slopes.

Rebuilding existing access roads and constructing a new road and ramp to provide access for heavy equipment into the upper reservoir.

Removing all silt and the remaining liner material inside the upper reservoir, in addition to concrete debris and exposed rebar in the breached area.

Designing, building and installing a cover and hatch for the vertical shaft that carries water back and forth between the lower and upper reservoirs. Ameren officials indicated that no decision about rebuilding the plant will be made until after the results of the investigations being conducted by the FERC and other agencies are completed.

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On Dec. 14 the AmerenUE Taum Sauk Plant's upper reservoir experienced a rupture in the northwest corner, causing 1.5 billions gallons of water to flow downward. The company implemented its emergency plan and assembled a multi- disciplinary team of experts, company officials and consultants to analyze the event and determine next steps.

Built in 1963, AmerenUE's Taum Sauk is a "pumped-storage" hydroelectric plant with a generating capacity of 450 megawatts. It stored water from the Black River in the upper reservoir, built atop 1,590-foot-high Proffit Mountain, and released the water to generate electricity when power is needed. The plant employs 12. The water flowed down a mile-long tunnel inside the mountain, turning turbine-generators to produce electricity. When power demand was low, the same turbines ran in reverse to pump water back to the upper reservoir.

AmerenUE is a subsidiary of St. Louis-based Ameren Corporation. Ameren companies serve 2.4 million electric customers and nearly one million natural gas customers in a 64,000-square-mile area of Missouri and Illinois.