Yes, DERRICKS is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, R 1, R 1, I 1, C 3, K 5, S 1.

Is it a valid word?

DERRICKS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a framework erected over an oil well to allow drill tubes to be raised and lowered
a simple crane having lifting tackle slung from a boom