Another great find! This explains all the repeater sites for Grand Canyon NP and lists the four nets for the park as well as the existence of a 5th net called the tactical net. I will have to check the database and see if it lists all of these nets. The EA specifically includes an administrative net and not a maintenance net as shown in the database so at least that part of the DB is incorrect.
How do you find these things? I thought I was pretty good at finding obscure, yet useful documents on the Internet, but you have found two gems that explain either frequency use or repeater locations and net names.
Keep um coming!