Identification of Saltwater Contamination

The extraction of underground oil or gas usually also generates large amounts of water, called 'produced water'. If not properly managed, it can cause local soil and water pollution.
 
In this case study, a GEM-2 handheld conductivity meter was used to quickly identify problem areas. In this case, the conductivity variations were large enough that the operator could explore the areas of greatest interest (as constrained by the local terrain) rather than following a fixed grid. This type of opportunistic approach can be very efficient. The whole survey area covered several square miles, but the immediately mapped area shown here required less than 2 man-days to survey.

This case study confirms that maps of apparent electrical conductivity (EC) are very useful in locating potential soil contamination. In the case of brine contamination, the EC values correlate well with laboratory analyses of both soil conductivity and concentration of chlorides. More generally, any type of contaminant whose EC contrasts with the environment can be delineated.