I spoke with the district there and they talked about some trails out near Berl Prairie Road. Thanks for the insight! I was also told the Pine Pass is the place to go for mountain riding.
FSJ has a snowmobile club as dose chetwynd the dunes are a bit of hills,open area and trails. When I lived there we use to spend the day in the dunes jumping and playing in the open areas. You can ride the power lines for miles and pick off but lines all day just need to explore and there is always ditch banging if u like that short of thing.