Underwater/Sub-Bottom Utility Locating
In the fall of 2012, a geophysical crew from Enviroprobe Service Inc. was mobilized to a coastal city in New Jersey to perform a geophysical investigation. The purpose of the investigation was to locate underwater/sub-bottom telephone utilities within a creek. The investigation utilized a cable locator with a submersible antenna, a Geonics EM31-MK2 system, and an EdgeTech 3100 portable sub-bottom profiler system.
It turned out the cable locator with submersible antenna was the most successful tool for this project. The underwater cables were pinpointed along their routes and their positions were marked on-site with anchored buoys. A high accuracy differential GPS was also used to record their positions. The recorded positions, along with estimated utility depths, were marked on maps for future references.
The EM31 data confirmed some findings of the cable locator survey. Due to the sub-bottom soil content and cable sizes, no signals indicating presences of cables were observable in the sub-bottom data.