Is it ok to put pine chips in my 3 toed turtle's enclosure?

Wood chips are a very poor substrate for turtles. You would do better using clean organic soil mixed with leaf litter or peat moss. Box turtles need to be able to dig and hide in their substrate and wood chips would not be healthy.

I am including a care sheet for eastern box turtles; the same information is applicable to three-toeds.

http://www.austinsturtlepage.com/Care/cs-easternbo...

Amalthea is right. Box turtles like to burrow, and her suggestion for substrate is a good one. Boxies need humidity in their enclosure, and wood chips of any kind would make the environment too dry. Pine, cedar, and fir chips are especially bad because they contain harmful oils that are toxic to turtles and can cause respiratory and eye problems, and possibly even organ damage if used over an extended period of time.