I recently heard someone openly wonder what was with all those hills along highway 83 near the turnoff to Garrison. No doubt many North Dakotans have passed that way and may have had the same question. Those hills are old mine spoils. A coal mine was in operation there from the 1940’s to the 1960. Keep in mind that this was before reclamation laws. Now of course, the overburden must be replaced and landscaped.