I'm pretty sure it was big blue. Someone else on here might know, but I believe that to get into 'grail' you stay right, make a sizable climb, then sidehill for ways then go up and over into the area.
Blue River is 90kms south of Valemount.
We just went there for the first time, and its not a highway upto the alpine. There are a couple chutes and some trees to navigate. We had lots of fresh snow, which is normally really nice, but there were no tracks for us to follow, so it was not easy to find our around even with two of our sleds outfitted with full color nav systems. I would suggest having a rider in your group that is familiar with the area, it can get "avalanchy" in places, and we dont need any more buried riders or bad press.