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Understanding geological history for trenchless installations: Part one

New trenchless installation work is not without risk. Small, low-cost projects combined with low exposure risk on some new installations may not necessarily warrant a detailed understanding of ground conditions, especially in areas of homogenous ground conditions not impacted by glaciers and coastal climatic actions.

On many large, engineered trenchless installations, it is imperative for the engineer to understand the geological history of the area and determine the possible consequences and controlling effects that the geology has on the proposed crossing. Deciphering the underlying geologic history (and local anomalies) drives selection of the best and most appropriate trenchless method.

Part one of this series looks closely at the complications associated with conducting long HDD crossings between and along the Coastal Plain Barrier Islands of the Southeastern US. An 18,000 LF installation of a 115-kV cable under Hamlin Sound SC will be reviewed in detail as a case example of the unique geological considerations associated with barrier island systems.

Read the full article in the Spring 2018 edition of the Northeast Journal of Trenchless Technology Practices..