Oh, so this is from the Big Bang Theory, right? Often Sheldon says some surprising things. Here , " Oh, what fresh hell is this?" means "Oh! What in the hell/what in the world is this?"

If you give me the whole sentence, then I can help you

"What fresh hell is this?" is a quote originally by American wit Dorothy Parker. It's an overly-poetic and dramatic reaction to a new situation... such as a knock on the door. The word "fresh" suggests "new", ie. the person is already experiencing hell, and the new situation is another hell. So yes, Sheldon is quoting here. "The hell" in "What the hell is this?" is merely emphatic. These are two entirely different quotes.

They are the same. Sometimes excavations need to be updated to keep them sup rising. Having the same curses for decades at a time can become stale.

"What the hell" is an informal and common exclamation of great surprise, especially when you happen upon a chaotic scene where you don't know what is going on. "What fresh hell...is this?" might be something you say when you are already in a difficult situation and then you encounter one more. Most of us would say something much cruder...