Project Header_Widows Creek
WIDOWS CREEK FOSSIL PLANT MAIN ASH POND & DREDGE CELL FINAL CLOSURE PROJECT
ENVIRONMENTAL

After the retirement of the Widows Creek Fossil Plant that powered northeast Alabama for six decades, Barnard safely stored its CCR into the plant’s coal ash complex.

Located on the Tennessee River near the town of Stevenson, Alabama, this coal-fired fossil plant run by the Tennessee Valley Authority (TVA) operated eight units at its peak and brought power to the region throughout the late twentieth and early twenty-first centuries. A changing regulatory and economic environment prompted TVA to gradually retire the facility in 2011, with the last of its original eight units closing in September 2015. Barnard worked with TVA to cap and cover nearly 400 acres of coal combustion residuals (CCR), so that further risk to the local environment can be reduced or avoided. The cap system consists of Linear Low Density Polyethelene (LLDPE) geomembrane, a geocomposite drainage media, and 18 inches of cover soil and vegetative cover.

OVERVIEW

Location: Stevenson, Alabama

Owner: Tennessee Valley Authority (TVA)

Engineer: Stantec, Inc.

Contract Type: Fixed Lump Sum, Fixed Unit Price

Status: Completed

HIGHLIGHTS

  • Cap system includes LLDPE geomembrane, a geocomposite drainage media
  • Applied 18 in. of cover soil and vegetative cover spanning 440 acres
  • 1.4 million CY of borrow material excavated and placed (cover soil)
  • Extensive dewatering and stormwater management
  • Permanent features included precast concrete box culverts, HDPE storm drain pipe, riprap lined ditches and sumps, and perimeter slope structural fill

1.6 million CY of CCR excavation and placement

400 acres of CCR capped and closed

350 acres of LLDPE liner and geocomposite

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