Yes and No. A lee neutral density filter was used and produced a very slight cast, but it was mostly just error on my part, after some global adjustments I made, it cooled down the photo too much.
Yeah, lee's generally don't have much of a cast.
On the plus side, the limestone on Timp is pretty close to 18% gray if you need to zero out your WB.
BTW, I'll agree with the others, this is a great shot.