To provide a broad range of services throughout Guam and the nearby Pacific islands, GEO formed two subsidiary companies:

GEOTESTING, INC., a Saipan, Commonwealth of the Northern Mariana Islands, corporation for services performing in the Northern Mariana Islands, the Federated States of Micronesia, Palau, and Marshall Islands.

MARIANAS DRILLING, INC., a Guam corporation providing drilling services.

Geo-Engineering & Testing has accredited construction materials testing laboratory on Guam for soils, asphalt, and concrete, and is actively performing such laboratory and field services..

Geo-Engineering & Testing with Marians Drilling have a fleet of four full-size drill rigs and two trailer or skid-mounted drill rigs for subsurface soil and rock investigations including test borings, test pitting, undisturbed soil sampling with Standard Penetration Testing to provide recommendations for structural foundation and earthwork designs, environmental drilling and groundwater exploration and sampling, and underground cavities in limestone rocks.

Geo-Engineering & Testing has performed over-water, off-shore test borings and samplings generally limited to 30 feet deep of sea water depth.