Hi Landon,
When choosing QC to perform, sites will only show up if the user has test lists that are visible to one of the groups they belong to. So the normal way to do this is to set up groups for each site (e.g. groups called "Site A: Physics", "Site B: Physics", "Site A: Therapy" ...) and then when you assign QC to units, make sure you only add the required groups to the "Visible To" section.
In order to make managing permissions easier across all campuses, you might want to set up "role" groups as well. So for example, let's say you have two campuses and want to have a common set of permissions for both physics groups, you might set up three groups:
Role: Physics - This is where you assign permissions for all physicists in the organization
Site A: Physics - This is what you will include in the "Visible To" field when assigning QC to Site A units. This group does not need any permissions assigned to it
Site B: Physics - This is what you will include in the "Visible To" field when assigning QC to Site B units. This group does not need any permissions assigned to it
Then physicists from Site A will belong to both the "Role: Physics" and "Site A: Physics" groups, and physicists from Site B wil belong to both the "Role: Physics" and "Site B: Physics" groups.
There's also been a "Site" column added to many of the tables in QATrack+ in the next release to make filtering things by site easier.
Hope that helps!
Randy