Question: When did the Army arsenal formerly located on the site now occupied by the Midewin National Tallgrass Prairie open?
Sentence (from "Joliet Army Ammunition Plant"): Joliet Army Ammunition Plant (JOAAP, formerly known as the Joliet Arsenal) was a United States Army arsenal located in Will County, Illinois, near Elwood, Illinois, south of Joliet, Illinois.
Relevant evidence: Yes