Newmont Mining Corporation

Adapted from Beyondthemine.com

Newmont's Batu Hijau mine in Indonesia transports our non-toxic and sand-like mine tailing through an undersea pipeline due to the earthquake-prone region and shortage of land for disposal. After discovering and patching a leak in the pipeline in 2005, the mine began using new technology to monitor the thickness of pipeline walls to ensure it remained intact.

At least twice a year, environmental crews shut down the tailing disposal system to insert a special inspection tool into the pipeline, where it continuously emits ultrasonic sound waves that measures how long it takes for the waves to bounce off the walls. These measurements indicate variations in thickness and contour to identify worn areas along the 2.1-mile (3.4 kilometer) pipeline.

It takes 24 hours for the tool to travel through the pipeline, which takes about 80 million measurements along the way. After the tool floats to the surface, data is downloaded for analysis. Using the data, the mine can create a two- or three-dimensional topography of the pipeline, helping engineers better predict when pipe replacement or patching may be necessary.