GTA's subsurface exploration division provides conventional test borings, cone penetrometer soundings, and monitoring well installations. Drilling areas of specialization include:
- Monitoring Well Installation
- Standard Penetration Test Borings
- Preliminary Percolation Tests for Septic
- Systems
- Instrumentation Installation
- Piezometers
- Electronic Cone Penetrometer Testing
- Dilatometer Testing
- Rock Coring
- Inclinometers