if( operatorRole.AllowedOperations.Count == 0 )
{
    operatorRole.AllowedOperations.Add( op1 );// all ops (op1-op4) are transient
    operatorRole.AllowedOperations.Add( op2 );
}

if (administratorRole.AllowedOperations.Count == 0)
{
    administratorRole.AllowedOperations.Add(op1);
    administratorRole.AllowedOperations.Add(op2);
    administratorRole.AllowedOperations.Add(op3);
    administratorRole.AllowedOperations.Add(op4);
}
using( var session = factory.OpenSession() )
using( var tx = session.BeginTransaction() )
{
    session.Merge(operatorRole);
    session.Merge(administratorRole); // <-- tries to insert op1, and op2 for the 2nd time, throws on UNIQUE violation. SaveOrUpdateCopy does the same
    tx.Commit();
}