Newton Power Plant landfill final cover planning, design, bidding support and CQA

Project Summary

Hanson provided a final cover planning document, design, bidding support and construction quality assurance (CQA) for Vistra’s coal combustion residual (CCR) landfill at the Newton Power Plant in Newton, Illinois.

Hanson evaluated the landfill topography, based on an updated topographic survey, and evaluated the necessary cuts and fills of in-place CCR to achieve final CCR placement elevations in particular areas of the landfill.

Hanson then prepared a final cover system design for the Newton landfill based on Alternative A from the planning effort its project team performed and provided to Vistra. The design included considerations for stormwater from the closed landfill areas and features to promote the water’s proper routing. In addition to management of the stormwater from the final cover, Hanson’s design considered management of the CCR-contact water from the open areas of the landfill.

Hanson also provided final cover bid process support and CQA for the landfill. These tasks included observing final ash grading, installing geomembrane and geocomposite drainage layers and vegetative soil cover, reviewing contractor submittals for geomembrane and geocomposite drainage layer materials and providing third-party prequalification and field installation conformance testing of the geomembrane materials before construction and during field installation, as well as preparing a stormwater pollution prevention plan for the final cover borrow areas and landfill project area.