Yes, GROUNDWORKS is a Scrabble word!

Letter values in Scrabble US: G 2, R 1, O 1, U 1, N 1, D 2, W 4, O 1, R 1, K 5, S 1.

Is it a valid word?

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

the fundamental assumptions from which something is begun or developed or calculated or explained
lowest support of a structure
preliminary preparation as a basis or foundation

Not playable in Scrabble US: UNDERSTRUCTURE.