The Rock Drill is a melee weapon in Silent Hill.
The game must be beaten once to obtain the drill, starting again in the "New Fear" mode. It is found in the Orridge Bridge Control Room. Like the chainsaw, Harry Mason will need the gasoline tank to use it.
The rock drill is very powerful, but it is heavy, difficult to handle, and Harry can't move while using it. It is less cumbersome than the unlockable chainsaw in Silent Hill 2, however.
Silent Hill: Book of Memories
The rock drill also appears in Silent Hill: Book of Memories. If obtained before the Earth Guardian is battled, it can prove to be quite effective against it, allowing one to defeat it with little trouble.