This month’s calendar features the granite marker noting the location of the original Chicago Pile-1 after it was disassembled and moved to the Argonne National Laboratory, Site A, in March 1943 and renamed Chicago Pile-2.

Now called the Red Gate Woods forest preserve, you’ll find an inscribed granite marker and an historical site marker. These mark the spot where Chicago Pile-2 was reassembled and built, along with other reactors. Chicago Pile-2 operated until 1954, at which time it was shut down and buried in Site A/Plot M Disposal Site. The gigantic hole dug was big enough for the 2-story high reactor, which was decontaminated and imploded for safety.

Other artifacts can be found in the area, including other concrete markers inscribed with historical information, the foundation of the labs, and more. The site can be found along the Pipeline Trail, which is poorly marked, but well worth the trek into history. Similarly, the trek from the main parking lot is as arduous.

Several markers near Site A/Plot M caution that radioactive material is buried in the area.

Be sure to download the November 2025 calendar featuring significant atomic events and atomic shots occuring during the month of November.

This month’s calendar features the Weldon Spring Site and Interpretive Center. Specifically, the featured image is the entrance to take the steps to the top of the site for an interesting panoramic view of the area.

The U.S. government acquired 17,232 acres of rural land, displacing 576 residents and three towns to establish the Weldon Spring Ordnance Works supporting World War II efforts for manufacturing TNT and DNT.

From 1956 – 1967, the U.S. Atomic Energy Commission constructed the Weldon Spring Uranium Feed Materials Plant to convert uranium ore concentrates to pure uranium oxides and compounds. Obviously, by 1987, with production ceasing, the DOE was left with a massive Superfund cleanup site.

The outstanding feature of the Weldon Spring Site is the 41 acre, 75 foot tall engineered disposal cell structure designed to contain the site’s waste. Now a public park with walking trails, bird watching, mountain biking, and native, restored prairie, the disposal cell stairway takes you to the top of the mound with a panoramic view of the area with historical markers.

Be sure to go to the Interpretive Center that explains more about the area, the TNT manufacturing, the Atomic Energy Commission’s use for uranium materials, and the Department of Energy cleanup.

Be sure to download the October 2025 calendar featuring significant atomic events and atomic shots occuring during the month of October.