Puget Sound faults about 1100 years ago (AD 900—930) an earthquake of magnitude 7+ uplifted Restoration Point and Alki Point, dropped West Point (the three white triangles in the Seattle Basin on the map), caused rockslides in the Olympics, landslides into Lake Washington, and a tsunami on Puget Sound. It extends as far east as (and probably terminates at) the Rattlesnake Mountain Fault Zone (RMFZ; the southern extension of the SWIF) near Fall City. This seems geologically reasonable, as both the SWIF and RMFZ appear to be the contact between Tertiary Crescent Formation basement of Puget Sound on the west and the older
Puget Sound Naval Shipyard and Intermediate Maintenance Facility the future. Gorst Creek Ravine near Port Orchard, Washington was a hazardous waste dump for the Navy's shipyard waste between 1969 and 1970, when the site was not permitted by local authorities to take waste. After several collapses since 1997 the landfill could blow out Highway 3. The landfill is an "ongoing source of pesticides, polychlorinated biphenyls and metals flowing downstream with the potential to affect groundwater wells, sport fisheries and the Suquamish Tribe's fish hatchery. In October 2014, the US EPA ordered the Navy to fix the problems. The Puget Sound Naval Shipyard contains five historic districts: These five