Exploration no. 146513 is a Geotechnical (depth 50.5 feet) named: B-3 described in subsurface document no. 64160. The document, a report titled Geotechnical Data Summary Report Madison Valley Drainage (NW Diversion Report) Seattle, Washington was prepared by City of Seattle, Public Utilities, Geotechnical Engineering on 06-01-2008 for a Utility project.