You really can't make this up. We have geological formations within our territory that are both incredibly stable as well as located within a dry climate. Yet we choose to use one of the least stable locations in terms of both geology, surrounding environment, and weather available to us.
I think the only way you could top this would be to place a vault at ground level that spanned the San Andreas fault.
> We have geological formations within our territory that are both incredibly stable as well as located within a dry climate.
Even more comical is that it's not like we didn't think of that because we literally do use that space for those reasons. We just also decided to fill the atoll with large amounts of nuclear waste... Seemingly for fun. To give the benefit of the doubt, for transportation logistics reasons.
I think the only way you could top this would be to place a vault at ground level that spanned the San Andreas fault.