It's hidden away in a place where you can only access it via Terminal. If you don't feel comfortable formatting drives from the command line, you should not be using the new APS file system. It's hidden deep for a good reason, and you will likely lose your data when the final version is released next year. This is meant for developers only. If you're somebody who just likes new and shiny things for the sake of being an early user, don't do it. This isn't for you.