Environmental Geophysics

Olson performs geophysical investigations for environmental site surveys. Our clients’ needs range from detection of subsurface metallic objects and features prior to intrusive activities, imaging of geologic conditions conducive to contaminant migration, to addressing changes in the subsurface during remediation.  Each site and each objective is always different for environmental projects.  Many projects are very straight forward with detection of buried metallic objects, both large and small (e.g., UST, pipes, UXO/MEC). Some projects require very intricate methods to image complex geology or hydro-geologic characteristics involving the lateral or vertical transport of contaminants.

Rarely, are geophysical methods capable of direct detection of the contaminants; however, free product in the form of LNAPL or DNAPL can sometimes be imaged with the right subsurface conditions and the right application of methods, including even multiple geophysical methods.  But at the low concentrations that many compounds are considered dangerous, or defined as contaminants of concern (COC’s), there is not sufficient contrast with the soil, rock or groundwater surrounding them to be successfully imaged using geophysical methods.

Environmental Geophysics, Olson Engineering

Applications for Geophysics to Environmental Problems

Underground Storage Tanks (UST)

Abandoned drums, pipes, or concrete containers

Utilities – hazardous or otherwise

Ordnance – Unexploded Ordnance (UXO) or Munitions and Explosive of Concern (MEC)

Spills or Free Product in the shallow subsurface

Abandoned oil wells

Lateral delineation of historic landfills

Vertical imaging of landfill thickness

Abandoned and covered / buried mud pits from oil well drilling

Unknown geologic conditions (e.g., karst, faults, dipping layers)


Time lapse monitoring (4D) investigation for flow movement

Abandoned Mine Lands (AML) – both coal and hard rock

Leak detection for liners

Acid Mine Drainage