Optimal Placement and Monitoring of Test Holes in HDD
Test holes should be positioned as close to the drill path as possible, typically within 5 to 10 feet, to ensure accurate soil data near the drilling location. However, they should also be far enough away to avoid potential issues like fracking through the geotechnical test hole. After drilling, geotechnical contractors grout the holes, filling them from the bottom up, and finish with natural fill at the surface. A geotechnical engineer or geologist typically monitors the fieldwork to ensure accurate soil assessment, providing critical information to guide drilling decisions without dictating whether the drilling should proceed.