randydutton

And how many weeks ready must the coastal WA counties be? In Grays Harbor we've heard 4 weeks Ready. There's going to be a lot of broken infrastructure between the coast and I-5, to include a WSDOT-owned 'Aberdeen Bluff' that looms over the Hwy 12 evacuation route. It hasn't been seismically retrofitted, nor is it on the WSDOT priority list because their grading matrix doesn't give points for emergency response needs, nor for adjoining rail lines. Over a thousand people would flee to that highway location that then could be crushed by a landslide, or blocked by a landslide that would strand the evacuees in the tsunami zone. And a landslide would also dramatically delay assistance to Grays Harbor.

Will you be incorporating gravitational wave sensors into ShakeAlert? Gravitational waves travel at the speed of light (faster than seismic waves), and the detection can be 5 sigma accurate. That should accelerate the warning, and possibly be less expensive than establishing the vast number of seismic sensors.

What's the percentages the Cascadia Subduction Zone event starts at the southern or northern end, not the middle where Washington State is? How long would the rift break take before it traveled to the middle?

The Ocosta Tsunami Evacuation Building is subject to a tsunami flood flowing from the south around Roberts Road. What is being done to prevent the water from pushing all the cars in the parking lot against the building and igniting? The Japanese experience discovered a lot of metal-on-metal sparking in flood waters, and three of their tsunami buildings having to be evacuated because of accumulated cars and debris catching on fire. The building is angled wrong such that it will slow down debris laden water; it has pillars and an alcove that will accumulate debris; and, because of the prevailing wind, the smoke and flames from any fire will flow directly over the building top where refugees will accumulate. Professor Gonzalez from UW who did the study wrote, “Fires ignited during a tsunami are common, so you’re absolutely correct to be concerned about burning debris risk at the Ocosta school. Your voicemail mentioned cars in the parking lot and, yes, both the impact of a car on the school as well as ignition of the gasoline is a real concern, too. I’m attaching the Ocosta study report, in case you haven’t seen it. Section 3.3 and Figure 7 are about the flow speed, which could reach dangerously high values 4 m/s on the Ocosta school campus. We modeled only the speed of the flow for the Ocosta study, and it might take some time to locate that model output. Direction of the flow was not computed; this would be valuable to your analysis, but the entire simulation would have to be repeated to save the direction at selected locations."

I had recommended a solution to mitigate the disaster potential, which is to build a geotube berm along the property's southern edge, building it up to 40', similar to Roberts Road. Is this being considered?

Fuel in Underground Fuel Storage Tanks (UST) may have their fuel contaminated, or may leak out, during a tsunami flood. According to my sources building code does not required to have backflow preventers, nor to be protected from tsunami debris impact. This is an issue I raised last year. What is being done to address this?

Further, what is being done to get propane tank distributors in tsunami flood zones to keep tanks from floating away and potentially igniting? Is there some restraining cable requirement? This also was a major issue in Japan's tsunami where many propane tanks opened up and burned.