X-111A/B Special Nuclear Material (SNM) Monitoring Portals

The X-111A and X-111B SNM Monitoring Portals were security portals used for safety screening of employees and equipment entering and exiting the X-326 Process Building. These portals were built in 1981. The X-111A (SNM) Monitoring Portal was located on the east side of the X-326 Process Building and had 900 sq ft under roof, and the X-111B (SNM) Monitoring Portal was located at the northwest corner of the X-326 Process Building and had 300 sq ft under roof. Both portals were of masonry construction with concrete floors and steel roofs. Both the X-111A and X-111B (SNM) Monitoring Portals were unoccupied and shutdown as security portals. The X-111A and X-111B (SNM) Monitoring Portals and the Extended Range Product structure were demolished on January 28, 2020 to clear access for water detention berm installation.


Completed in 1981


Demolished in 2020

Building Size

900 sq. ft. (X-111A), 300 sq. ft. (X-111B)

Take a Look Inside the Plant

Using our interactive map, you can locate individual buildings within the plant and learn more about its purpose throughout history. Clicking on a building will bring you in-depth information, photos, and videos.

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