Geotechnical Engineering Services


STL offers comprehensive geotechnical engineering to architects, developers, municipalities, government agencies, etc.
Our engineering department consists of professional and staff engineers, geologists, and technicians familiar with the area geology and environment. Our engineers and drilling crews are certified under the OHSA 40-hour training for hazardous material.

Our drilling equipment consists of two truck-mounted drilling rigs capable of drilling and rock coring to a depth of approximately 300 feet using hollow-stem augers, wash borings, and/or casing advancers and are equipped with wire line and automatic sampling hammers. STL abides by strict schedules of maintenance for all rigs and can assure our clients that our field crews rarely experience equipment breakdowns in the field

Services Include:

  • Specification preparations and review
  • Geotechnical, geological, and hydrologic studies
  • Detailed site investigations
  • Site grading specifications
  • Drilling and sampling (rock and soil)
  • Slope indicator installation and monitoring
  • Underpinning and soils stabilization
  • Foundation inspection (footings, caissons, piles)
  • Structure performance monitoring
  • Construction sequence evaluation
  • Dewatering systems design
  • Borrow availability inspections
  • Dam safety inspections
  • Soil laboratory testing
  • Pavement design


  • Preliminary site studies
  • Site development studies
  • Unique physical evaluation
  • Shoring and bracing design
  • Erosion control design
  • Slope stability analysis
  • Subgrade inspection
  • Foundation recommendations
  • Pile and drilled pier load testing
  • Groundwater monitoring
  • Evaluation of proposed borrow
  • Earth dam design
  • Grout injection studies
  • Compaction test strip evaluation
  • Failure investigation analysis