Coal ash engineering: A look back at the past and peak into the future

Ramachandran Kulasingam, Consulting

Description

Coal ash engineering has come a long way after jolted by the slide in Kingston in 2008 to closures of some of the largest and complex ash basins in the country underway in 2024. Research studies, field investigations, analyses, designs, dewatering, excavations, additional ash slides, and more forensic evaluations have all taken place. Engineering work has covered closures in place, closures by removal, hybrid closures, and landfills. Lessons have been learned, some forgotten, and some relearned. The merits of active versus passive dewatering, role of engineering in evaluating ash excavation stability versus pursuing a means and methods contractor experience approach, need for instrumentation and monitoring versus observational methods have all been debated from conference rooms to construction trailers. These debates still continue. Construction work for most of the largest ash basins that are being closed by removal or using hybrid closure methods is expected to continue till 2035 to 2040 timeframe. The looming potential impact of the legacy rule could bring a slew of large ash basins, that were or are being closed in place or using hybrid methods, for additional engineering work that could include excavation and landfilling. The role of dewatering, instrumentation, and geotechnical analyses will likely expand to cover these emerging challenges. The timeframe for ash basin closure construction could extend into 2040s if legacy rule impacts large valley fill closure in place or hybrid closure sites. This presentation will look back at the past as well as take a peak into the future in terms of lessons learned and challenges.

 
May 15th, 11:00 AM May 15th, 11:30 AM

Coal ash engineering: A look back at the past and peak into the future

Grand Rapids, Michigan

Coal ash engineering has come a long way after jolted by the slide in Kingston in 2008 to closures of some of the largest and complex ash basins in the country underway in 2024. Research studies, field investigations, analyses, designs, dewatering, excavations, additional ash slides, and more forensic evaluations have all taken place. Engineering work has covered closures in place, closures by removal, hybrid closures, and landfills. Lessons have been learned, some forgotten, and some relearned. The merits of active versus passive dewatering, role of engineering in evaluating ash excavation stability versus pursuing a means and methods contractor experience approach, need for instrumentation and monitoring versus observational methods have all been debated from conference rooms to construction trailers. These debates still continue. Construction work for most of the largest ash basins that are being closed by removal or using hybrid closure methods is expected to continue till 2035 to 2040 timeframe. The looming potential impact of the legacy rule could bring a slew of large ash basins, that were or are being closed in place or using hybrid methods, for additional engineering work that could include excavation and landfilling. The role of dewatering, instrumentation, and geotechnical analyses will likely expand to cover these emerging challenges. The timeframe for ash basin closure construction could extend into 2040s if legacy rule impacts large valley fill closure in place or hybrid closure sites. This presentation will look back at the past as well as take a peak into the future in terms of lessons learned and challenges.