Due to new regulations, the sludge sediment basins at this coal-fired power plant required removal of the existing liner system and protective concrete cover. The basins were retrofitted with a new liner system meeting the requirements of Laws and Codes, including federal CCR rules and regulations.
"Trans Ash was able to work closely with the owner to reevaluate the schedule and modify the task priority list."
Project Challenges & Solutions
Several items were encountered throughout the life cycle of this project and created the following challenges:
- Due to permitting delays, the majority of the project was executed during the fall and winter months. The weather encountered during this time of year caused setbacks in the schedule. Trans Ash was able to work closely with the owner to re-evaluate the schedule and modify the task priority list.
- During demolition, CCR’s were found outside the limits of the existing liner system. This impacted the quantity of existing onsite clay that was planned to be re-used. Fortunately, the borrow source for the new clay liner was adequate enough to provide material to account for the negative balance in subgrade fill.
- Several large rain events caused project delays. The low permeability borrow source was located on a piece of property on the opposite side of the river from the project site. During a flood event, the bridge used for crossing the river was closed and haul trucks had to be re-routed. This caused a significant impact to the haul distance so additional trucks were mobilized to ensure production rates were maintained.
- During the electrical system replacement, an existing duct bank was found to be located in an unexpected location. This required the duct bank to be relocated earlier in the project than originally anticipated, which impacted the liner system installation phasing. Trans Ash worked jointly with the design engineer and owner to implement the best solution to this problem.