Figure 6. Geological examination of the pipeline was timed to fall between digging
the trench and installing the connected sections of pipe. This photo shows this stage of construction where the pipeline crossed the top
of a sandy gravel terrace along the Androscoggin River valley in Gilead.
The gravel was left by streams from melting glacial ice, as they discharged
their sediment load into a lake that once existed in this part of the valley
("glacial Lake Bethel"). This feature is called a delta.
Last updated on October 6, 2005