Abstract

Engineering-geologic evaluations of conditions, many of which constitute some form of natural hazard along the alignment of the proposed Kern River Pipeline, were conducted to provide a basis to 1) reduce the risk of damage to the pipeline which could result in a threat to public safety, 2) reduce the owner’s exposure to loss of pipeline function (i.e., economic loss), and 3) comply with mitigation measures required by the Federal Energy Regulatory Commission (FERC) as part of the project Final Environmental Impact Statement (FEIS). The FERC developed 156 measures to mitigate environmental impacts related to the proposed pipeline. Of these, 17 pertained to geology and geotechnical engineering. Specific scientific and engineering studies were conducted to address design issues related to avalanches, volcanic eruption, fault rupture, liquefaction, slope instability, hydrocompaction, subsidence, springs, shallow ground water, and stream crossings.

Avalanche, volcanic eruption, liquefaction, slope instability, hydrocompaction. and subsidence processes, and springs and shallow ground water were found to represent insignificant hazards to a buried, high-strength pipeline in southwestern Utah for a variety of reasons and little in the way of special design provisions were warranted. Quaternary faults were crossed at three locations in southwestern Utah in a way intended to reduce the risk of damage in the event of a future surface rupture event. Streams were evaluated for scour and lateral-bank-migration hazards associated with the 100-yr flood event.