these aren't much steep as the Bhor - n Thull were even 3 phase loco needs a Banker. here its, necessary for WAP-4 and below. for WAP-7, its a not so tough work.
similarly a single WAP-7 can easily pull 12-14 coach even in between Kottavalasa - Araku section without bankers, but if its a 18+ or 19+, it has to get banker.