Traditional wisdom tells us to store them in a rodent proof container which water can freely flow through. Something like a wooden box with slats (I used treated 2x12 for the sides and 5/4 decking boards for the top and bottoms) and 1/4 inch hardware cloth (a wire fence-like material with 1/4" mesh) to keep our the mice and moles. Line the bottom of the box with the hardware cloth and then again with aluminum window screen to keep the sand and seeds inside. Then start with a couple inches of sand, and add the sand/seed mix and top off with more sand. I then lay in another layer of hardware cloth and put the boards on the top.
Most commonly, you will want to bury them in an area suitable for growing ginseng (moisture, drainage etc). Then burry them. Dig the hole and line it's bottom with sand deep enough so the box will be at least 6-10 inches under the surface when you fill in the dirt around the hole.
If you have access to a cooler, you can put the seed/sand mix in plastic totes and put them into the cooler at about 34 degrees until it gets cold outside, then just keep them from getting into the lower 20s. In the spring, take them out of the cooler, and put them in a shady spot (inside a barn or other open air building).
Above ground stratification doesn't encourage grinning like most folks like to see, but the seed normally comes out pretty good. You also help avoid soil bourne diseases. (speeking of which, you might want to treat the seed before you put it into the box with one of the fungicides labeled for use as a ginseng seed treatment.