Electromagnetics (EM)

Excel operates EM31, EM34, and EM38 Geonics Ltd. electro-magnetometers; all equipped with a GPS antenna continuously collecting real time data. Depending on the EM instrument being used, accuracies can vary from 0.1 to 0.3 mS/m, and resolutions from of 0.01 to 0.05 mS/m. Electromagnetic surveys provide measurements of the apparent conductivity integrated over a volume of the subsurface to depths dependent on the transmitter and receiver coil separation, as well as soil conductivity.

Applications:

• Locating and mapping buried wastes, tanks and metallic objects
• Detecting and mapping lateral changes in natural geologic and hydro-geologic conditions
• Locating and mapping contaminant plumes
• Investigating ground water pollution

Advantages:

• Low- cost
• Lightweight and easily portable
• Non-intrusive
• Easy to operate
• Excellent lateral resolution with profiling
• Measurement depths range from 1 to about 65 meters.