work underway on a water-discharge structure we designed for poor soil conditions
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ash pond expansion

ash pond expansion
Minnesota Power

ash-disposal pond and liner design enables quick construction and leak-free performance

When the fly-ash and bottom-ash disposal facility at the Laskin Energy Center in Biwabik, Minnesota, was nearly full, Minnesota Power asked Barr for assistance designing and permitting a new facility that would accommodate 10 to 15 years’ worth of coal ash and meet new state requirements for environmental protection.

We worked with Minnesota Power to identify and evaluate concepts for a new 25-acre facility that would meet ash-disposal, water-temperature, and water-quality needs at the power plant. After evaluating options and gathering temperature and turbidity-gradient data for facility sizing, we developed a liner concept that used synthetic materials and could be placed quickly, greatly reducing the time needed for construction. Barr also provided construction assistance services and designed a pumphouse with double-suction line-shaft vertical-turbine pumps to recycle ash-transport water to the plant.

The pond was built in a single construction season and a full-scale post-construction leak test showed that the liner is performing as designed.