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Compaction/Settlement of the soil
Type of Soil and density
Years pipeline has been in service
Depth of Cover (DOC)
Moisture Content
Uniform Support Underneath Pipeline i.e., Bedding
Overbends and Sags
Horizontal Bends – Point of Intersections (PIs)
Note 1: There are rules of thumb that most US pipeline operators use for determining trench width with no saturated soil:
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