1.0 Site Identification

Type of Site: Complex Decommissioning Site
Location: Maryland Heights, MO
License No.: 24-16273-01
Docket No.: 030-10716
License Status: Terminated
Project Manager: George Alexander

2.0 Site Status Summary

The Sigma-Aldrich Company’s (Sigma) Fort Mims Site is located at 11542 Fort Mims Drive, Maryland Heights, Missouri in a commercial/industrial park (Agencywide Document Access and Management System [ADAMS] Accession No. ML091330309).  The site consists of a three-acre parcel of land previously used for the radiolabeling of chemicals with carbon-14 (C-14) and tritium (H-3). 
The former building facility was constructed in the late 1960s and expanded in 1981.  The effluent discharge points were an exhaust stack and a septic tank, which was located beneath the former facility.  The use of the septic system ceased in 1981.  The former building facility including the structures, foundation, and septic system were decontaminated, decommissioned, and removed from the site in 2010. In 2014, the asphalt parking lot was removed.
By letter dated August 22, 2019 (ADAMS Accession No. ML19273A163), as supplemented on April 27, 2020 (ADAMS Accession No. ML20120A544), and October 19, 20203 (ADAMS Accession No. ML20294A191), Sigma submitted an application to amend their decommissioning plan and terminate NRC Materials License No. 24-16273-01. In this application, Sigma stated that the: (1) soil and groundwater at the Fort Mims Site was fully characterized, (2) site meets the criteria for unrestricted release as stated in Title 10 Section 20.1402 of the Code of Federal Regulations, “Radiological Criteria for Unrestricted Use,” and (3) residual radioactivity at the site is As Low As Reasonably Achievable (ALARA). Sigma also provided a signed NRC Form 314, “Certificate of Disposition of Materials,” documenting that all authorized activities have ceased, and all radioactive waste was transferred to the Toxco Materials Management Center in Oak Ridge, Tennessee.
As discussed in a Safety Evaluation Report (ADAMS Accession No. ML21300A384) dated November 16, 2021, the NRC staff reviewed the revised decommissioning plan with the site-specific dose model and license termination request. Based on Sigma’s dose analysis and the NRC’s independent and confirmatory surveys and analyses, the NRC staff concluded that the Fort Mims Site meets the dose criteria for unrestricted use and that the residual radioactivity is ALARA, consistent with 10 CFR 20.1402.
The NRC staff completed an environmental assessment (EA) of Sigma’s request to amend their decommissioning plan and terminate their license (ADAMS Accession No. ML21277A097). In this EA, the NRC staff concluded that there would be no significant environmental impacts and approval of the license amendment would not warrant the preparation of an Environmental Impact Statement. Accordingly, it was determined that a Finding of No Significant Impact was appropriate.
As documented by License Amendment 21 dated November 16, 2021 (ADAMS Accession No. ML21300A383), Sigma’s Materials License No. 24-16273-01 was terminated.

3.0 Major Technical or Regulatory Issues


4.0 Estimated Date For Closure

Part 30 License Terminated November 16, 2021

Page Last Reviewed/Updated Wednesday, June 29, 2022