The Joliet Army Ammunition Plant (JOAAP), originally known as the Elwood Ordinance Plant (EOP) on the east side of Illinois Route 53 (formally US Route 66) and the Kankakee Ordinance Works (KOW) on the west side of the road, was authorized by the federal government in 1940 to produce ammunition and explosives for the U.S. military.
This site was chosen because ammunition could be transported to any coast by train within two days.
To construct the plant, 36,645 acres were purchased at a cost of $8,175,815. Construction costs totalled over $81 million. Seventy-seven such plants were built during World War II to support wartime needs. At the time they were built, the Joliet plants were considered the largest, most sophisticated munitions plants in the world. Both the Elwood and Kankakee plants became a training base that supported the Allies' effort. At peak production during WW II, over 10,425 people were employed at the two plants.
The Elwood facility loaded over 926,000,000 bombs, shells, mines, detonators, fuzes, and boosters, and the Kankakee facility set a national record producing over one billion pounds of TNT.
The Elwood and Kankakee Plants were combined and redesignated the Joliet Arsenal in 1945, when operations were placed on standby. The Arsenal was reactivated during the Korean War, from 1952-1957, and then again during the Vietnam War, when it was again renamed as the Joliet Army Ammunition Plant (JOAAP). TNT production stopped in 1976, and by the late 1970's, most operations at JOAAP ceased. The combined acreage of JOAAP at the time it was declared inactive was 23,543.
The listed coordinates are for a trailhead parking area for the Midewin National Tallgrass Prairie.
If you look to the west beyond the fence, you will see several grass-covered mounds. These are bunkers, constructed during the 1940s when the Joliet Army Ammunition Plant (JOAAP) was created. Designed to store explosives, their concrete walls are 3 to 5 feet thick and their earthen covering both camouflaged them from aerial view and helped to keep the TNT inside at a stable temperature. Nearly 300 hundred of these bunkers remain at Midewin today.
Normally, these bunkers are not open to the public, but if you watch the Calendar of Events, occasionally, they will have tours of the bunkers a few times during the warmer months.
The close-up photo of the bunker was taken during a private tour arranged for my office.
Also found within the old arsenal boundaries is the Abraham Lincoln National Cemetery (
Waymark WM1T9F) many of whom served in World War 2 and the Arsenal Explosions Memorial (
Waymark WM1V2R) to honor those who were killed while making the munitions during World War 2.