Lambert Airport Expansion Project

LAMBERT AIRPORT EXPANSION PROJECT

St. Louis, Missouri

In 1997, the City of St. Louis retained Reitz & Jens to perform a preliminary geotechnical survey for the runway expansion at Lambert International Airport. The 9,000 foot long runway expansion and associated infrastructure improvements required moving of over 10 million cubic yards of earth, with cuts up to 55 feet deep and fills approaching 65 feet in depth. One MoDOT road was placed in a cut-and-cover tunnel beneath the new runway and ramps.

The expansion occurred in an area of varying geology ranging from soft lacustrine deposits to modified windblown loess over residual clays, all of which was underlined by Pennsylvanian bedrock. The survey provided an overview of:

• geological and subsurface conditions within the expansion
• the depth of bedrock and the effects on construction
• soils characteristics including shrinkage and swell potential
• identified slope stability and embankment issues
• identified groundwater conditions and the effect on construction
• estimated soil properties for preliminary pavement design.

The thorough research included a review of prior geotechnical investigations performed by Reitz & Jens. A total of 38 deep test borings were advanced to determine the subsurface conditions. The borings ranged from 25 to 80 feet deep which sampled both the overburden materials and underlying bedrock. Both short- and long-term groundwater elevations were also recorded for future use. The results of the survey were used in the Airport's long-term expansion plans.

In 1999, the Airport Authority selected teams to provide Geotechnical Foundation Engineering (GFE) and Drilling, Sampling and Laboratory Evaluation (DSLE) Services for the remainder of the Airport Expansion program through 2005. Reitz & Jens was a key member on each of these teams providing geotechnical engineering evaluation and peer review services.

Between 1999 and 2002, Reitz & Jens services on the DSLE contract included quality assurance oversight of all field operations during drilling and sampling, and instrumentation installation. During approximately a 1-1/2 year period, Reitz & Jens also completed over 65 One-Dimensional Consolidation (ASTM D-2435), 85 CU Triaxial Strength (ASTM D-3080), 215 UU Triaxial Strength (ASTM D-2850), and 270 Atterberg Limits (ASTM D-4318) tests on recovered samples from this project, in their in-house soils laboratory. The firm was also responsible for providing quality assurance review of all drilling and testing reports, as well as the final DSLE reports which were submitted under 22 separate work orders. The DSLE contract was substantially complete by the fall of 2002.