One Seam at a Time: Interactive Quality Assurance to Identify Coal Seams during Foundation Construction-PPT Presentation

PPT Presentation

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The Aeolus–Jim Bridger project involved constructing a 138-mile, 138-kV transmission line in southern Wyoming, with 551 lattice-tower and steel-pole structures. The region’s variable sedimentary geology, coal seams, unpredictable groundwater, limited site access, environmental restrictions, and pre-winter deadline made foundation construction challenging. Pre-construction geotechnical data were limited to 118 borings, roughly one every three miles.<br /><br />Designers used geologic mapping and risk assessments to assign foundation profiles while allowing field adjustments based on actual conditions. Planned foundations included drilled shafts and direct-embed poles. Where coal was anticipated, designs extended one foot below the seam.<br /><br />A proactive quality-assurance program supported construction in real time. Licensed geologists and trained staff verified subsurface conditions, coordinated with the owner, engineer, and contractor, and helped determine when design changes were needed. Geologists also anticipated coal trends and groundwater conditions so teams could respond quickly. Project records were completed online.<br /><br />Construction revealed mismatches at 11 sites, including four unexpected coal seams, two seams larger than expected, and one unexpected groundwater occurrence. Despite these surprises, construction began in April 2019 and finished in mid-December. The project demonstrates how interactive, field-based QA can provide flexibility, reduce downtime, and help control schedule and costs on long linear construction projects.

Keywords

Aeolus-Jim Bridger project

transmission line

southern Wyoming

foundation construction

geotechnical data

coal seams

groundwater conditions

geologic mapping

quality assurance

linear construction projects