electrical resistivity

Advanced Geophysical Services (AGS) provides non-intrusive subsurface investigation services for environmental, engineering, and construction projects. Formed through the acquisition of Advanced Geological Services by EPI Geophysics, AGS brings over 30 years of experience in geophysical investigations and subsurface characterization, with in-house licensed Professional Geologists and experienced geophysicists. The company supports projects across Pennsylvania, New Jersey, New York, Connecticut, Delaware, Maryland, and beyond.

borehole geophysicsGround Penetrating Radarmicrogravityoil tank sweepSeismic methodssubsurface investigationutility locating and mapping

Certerra Subsurface delivers integrated subsurface investigation services including geophysical surveys, drilling, utility investigation, leak detection, and infrastructure assessment. The company provides technology-enabled testing, inspection, and certification services to assure quality and advance innovation in infrastructure, helping engineers, mine operators, and environmental professionals understand underground conditions and reduce uncertainty.

airborne surveysCCTV pipe inspectiondownhole geophysical imagingdrillinggeophysicsGround Penetrating Radarleak detectionpotholingSamplingseismic refractionutility surveying

Cultural Resource Analysts, Inc. (CRA) is a full-service cultural resource consulting firm established in 1983 in Lexington, Kentucky. A certified small business with over 40 years of experience, CRA provides archaeology, architectural history, historic preservation, and compliance services to public and private sector clients across the country.

archaeological surveyarchival researchbioarchaeological analysiscartographycemetery excavation and reintermentearth conductivitygenealogical researchgeophysical surveyGISGround Penetrating Radarhistoric preservation planningLiDARMagnetometryremote sensingSfM photogrammetry