Hansen, Allen & Luce (HAL) recently oversaw the successful construction of Cell 8 of Clean Harbors’ Grassy Mountain hazardous waste facility. The facility is located in Utah’s Great Salt Lake Desert, about 75 miles west of Salt Lake City. HAL previously completed design and permitting for the new cell, which is the first to be completed in Utah in 25 years.
The design features a 24.5-acre site, 27-foot embankments, leachate collection and removal systems, and a triple-layer HDPE liner. The cell capacity is 785,000 cubic yards.
HAL helped resolve several design and permitting challenges, including demolishing two unused cells, recycling the geosynthetics, constructing a new wheel wash for landfill trucks, and accommodating a projected 10-foot settlement of the underlying soil.
To assure the highest quality, HAL provided full-time, on-site observers throughout construction. The HAL team was responsible for documenting the earthwork, liner installation, and testing results, as well as providing construction surveys.
Planning, design, and permitting for the project began in 2015 and construction began in March 2019. State regulators issued approval for the cell to begin receiving waste in February 2020.
“It was a success, many years in the making,” said HAL vice president Gordon Jones, P.E., who managed the project.