Cenex Bottoms Upgrade Program

Cenex-Harvest States (CHS) refinery constructed a larger decoking facility known as the bottoms upgrade program at the west side of the existing refinery in Laurel, Montana. The project consisted of constructing a large delayed coker unit and several larger mat foundations, pipe racks, storage tanks, towers, compressors, cooling towers, and other various equipment. The majority of these structures were to be supported on conventional spread footing foundation or mat foundations supported on native sandy gravels. SK Geotechnical’s scope of services included:

  • Performing a geotechnical evaluation, including twelve soil borings, providing recommendations for the design and construction of suitable foundations for the project, recommendations for earthwork and other phases of site development, soil data for the design of underground utilities, and geotechnical data for establishing the seismic design criteria.
  • Conducting a wide variety of laboratory tests, including moisture content, Atterberg limits, grain size distribution, unit weight, consolidation, unconfined compression, California bearing ratio, Proctors, and corrosion tests.

During the construction phase of the project, SK Geotechnical performed:

  • Subgrade observations to evaluate subgrade soil conditions and conformance with project specifications.
  • Compaction tests with nuclear densometers to confirm that fills and backfills were placed and compacted in accordance with project specifications.
  • Concrete and grout testing and inspection on foundations, footings, columns, piers, pedestals, walls, and road paving, which included slump, air content, and compression tests on concrete cylinders.
  • Obtaining concrete cores and performing compression and density testing.

During construction, our personnel were on-site full time performing testing and inspection services. Testing on the project included 212 compaction tests, 230 sets of concrete cylinders, 23 sets of grout cubes, two sets of grout prisms, 212 compaction tests and 32 concrete core samples.