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AmerenUE Begins Adding Alums to Remove Suspended Clay From Black River
AmerenUE today began using flocculates\-alums and a buffering agent that cause suspended particles to settle out of water---to remove suspended clay from the Taum Sauk lower reservoir. This is a major step toward clearing the muddy appearance of the lower reservoir and water releases into the East Fork of the Black River.

Today's activities are part of an implementation plan the Missouri Department of Natural Resources approved Jan. 20, after analyzing the materials and approach and determining that they pose no threat to humans, wildlife or aquatic life. Alums are commonly used to treat drinking water.

The initiative is part of a multi-pronged company and state effort to restore the river and the Johnson's Shut-Ins State Park, following the Dec. 14 failure of AmerenUE's Taum Sauk Hydroelectric Plant upper reservoir that caused massive flooding.

The company expects to complete the application over the next three days and to proceed with each only during daylight and reasonable weather conditions. This morning, a crew on a specially designed boat fitted with surface application spray bars began applying alums evenly over a 60-foot-wide path. Dual, 65-horsepower hydraulic motors power the 24-foot boat, and the depth and speed of the vessel are computer-monitored to maintain uniform dose; however, the vessel is also is equipped with redundant, manually operated systems.

Operators navigate with a specially modified differential satellite global positioning system. During each application, a visual plot shows on a computer screen the areas where the flocculates have been applied. The accuracy of this system is within three feet of the desired path.

Computer-based readings help operators calculate the rate of flocculate delivery at any moment during the application. For each trip, the computer records the average water depth, the path length, the amount of material distributed and the area treated so the project can be continuously monitored. Scientists will be testing water in the reservoir and all released water immediately downstream of the reservoir for dissolved oxygen, alkalinity, turbidity, the condition of all aquatic life and other characteristics.

"We expect to see the water clear up within approximately 12 to 18 hours after application," says Michael L. Menne, AmerenUE vice president for Environmental, Safety and Health. "We appreciate the support of the Department of Natural Resources throughout this process. Clearly our shared goal is to prevent more sediment from entering the Black River and any bodies of water feeding into the Black River---both to protect aquatic life and to return the Black River to its former clarity."

After the water treatment, AmerenUE will begin lowering the water level of the reservoir in an attempt to further remove sediment deposited in the Black River.


On Dec. 14 the AmerenUE Taum Sauk Plant experienced a breach in the upper reservoir that caused flooding in the Johnson Shut-ins and resulted in the closing of one road. The plant's 1.5-billion-gallon upper reservoir experienced a rupture in the northwest corner causing 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. It stores water from the Black River in the upper reservoir, built atop 1,590- foot-high Proffit Mountain, and releases the water to generate electricity when power is needed. The plant employs 12. The water flows down a mile-long tunnel inside the mountain, turning turbine-generators to produce electricity. When power demand is low, the same turbines run in reverse to pump water back to the upper reservoir.

AmerenUE is a subsidiary of St. Louis-based Ameren Corporation. Ameren companies serve 2.3 million electric customers and 900,000 natural gas customers in a 64,000-square-mile area of Missouri and Illinois.

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