Seismicity, safety, and science.

Everything in Alaska is bigger, including earthquakes. While seismic risk near the Deposit is relatively low, we are taking extraordinary steps to protect people and the environment. Mine facilities will withstand the greatest possible seismic activity predicted by science.



Our design accounts for Alaska’s largest earthquakes.

We used USGS data to calculate peak ground acceleration for “maximum credible earthquakes” along the very same subduction zone which created the 9.2 magnitude quake in 1964.


We assume the maximum quake at 
the Lake Clark Fault.

There has been no major seismicity along the Lake Clark Fault for 11,000 years. That’s since the last Ice Age. But our facilities are still designed to withstand the largest possible quake there.


We even assume a floating fault at the mine site itself.

Even though no evidence 
 of a fault exists, our mine facilities are designed to remain safe and maintain integrity during a magnitude 6.5 quake directly below the Pebble mine site.