GFA Owns and operates its own drilling equipment and support vehicles and can respond quickly to requests for subsurface soil sampling and installation of monitoring wells. Our drilling crews know auger and wash boring techniques. They are experienced in split barrel sampling and rock coring and utilize standard penetration tests to collect data in order for our soil engineers and geologists to determine the nature of subsurface soils and general geomorphic conditions.

Drainage tests are also conducted by our field crews such as infiltration and exfiltration tests to determine the site soil drainage characteristics. The data is then used to determine hydraulic conductivity (K) values useful in the sizing of drainage areas.

Test excavations performed with rubber tire backhoes or track mounted excavators are also used to supplement drilling activities where additional investigations may be useful such as unearthing buried debris or deleterious soil deposits.

All soil samples are thoroughly examined visually in our laboratory by our soil engineers to obtain an accurate definition of the geomorphic conditions and properties of the soil. Random laboratory tests are performed to verify visual classifications, including gradation analysis and organic content of soil samples. Detailed boring logs and other field data are then finalized to depict the encountered soils including illustrating the penetration resistance during drilling and sampling.