Flathead County LandfillGeolocation: 48.4242, -114.1532

This project presents the results of Construction Quality Assurance (CQA) services provided by NTL Engineering & Geoscience, A Terracon Company, during construction activities associated with the Phase IV-A excavation and final closure of the north and east slope construction project at the Flathead County Sanitary Landfill in Flathead County, Mont. The purpose of the closure is to provide a barrier on the slopes of the landfill that have attained final elevation. The two slopes closed for this project encompassed an area of approximately 14 acres. The final cover/barrier was proposed to be an earthen barrier with maximum permeability of 1x10-5 cm/sec and have a minimum barrier thickness of 2.5 feet overlain by 0.5 feet of topsoil. Our project involvement consisted of fulltime construction observation, field density testing, index property testing on borrow materials, laboratory permeability testing on remolded samples, and field permeability testing using two stage borehole permeameters (also referred to as a Boutwell).

Flathead County, MT


Associated Office

Great FallsGeolocation: 47.4908, -111.3376
The Great Falls office was formed in 1991 as NTL Engineering & Geoscience, Inc., an employee-owned Montana corporation practicing in the geotechnical, construction materials, and environmental engineering and testing fields. NTL joined Terracon in 2008 and officially changed its name to Terracon in 2013. The Great Falls engineering staff have a wide range of geotechnical experience on projects ranging from large industrial facilities to dams, bridges, highways, landslides, rockfalls, retaining structures, defense facilities, and seismic-related studies with geographic project involvement…