Regional planning context
Why the earth profile has to be measured at the project
Eugene has wet winters and reliably drier summers. Willamette Valley alluvium, fine-grained valley soils, volcanic-derived material, and foothill colluvium create different compaction and moisture-response conditions.
Regional descriptions help identify station coverage, candidate line directions, and likely changes along an alignment. They do not provide a design resistivity for a parcel or route. A Wenner result is apparent soil electrical resistivity for the documented array and field condition.
