Great hike, 25 degrees with clear blue sky, saw one other person the entire walk.
So this trail really has nothing to do with Coal Lake except you are Coal Lake Rd and drive past Coal Lake. Coal Lake is like 200 ft from the parking area. Drive past this trail to the end of the road, this is the trailhead for Independence Lake and North Lake. The mile walk up to Independence is a real nice warmup. When you get to the far end of this pretty little lake just follow trail, up. When you get to the top you will sort of follow the hill around to the right then start down towards North Lake. This part of the trail is the one shovel wide type and is steep and slick.