[Federal Register Volume 86, Number 223 (Tuesday, November 23, 2021)]
[Notices]
[Pages 66597-66600]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-25551]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 30-10716; NRC-2020-0214]


Sigma-Aldrich Company, Fort Mims Site

AGENCY: Nuclear Regulatory Commission.

ACTION: Environmental assessment and finding of no significant impact; 
issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is considering 
amending the NRC's Materials License No. 24-16273-01, issued to Sigma-
Aldrich Company (the licensee), for possession of byproduct material 
incident to radiological survey, storage of waste awaiting disposal, 
and decontamination, and remediation of the Fort Mims Site. The 
proposed amendment is to revise the decommissioning plan and terminate 
the license for the licensee's Fort Mims Site in Maryland Heights, 
Missouri. The NRC staff is issuing an environmental assessment (EA) and 
finding of no significant impact (FONSI) associated with the proposed 
action.

DATES: The EA and FONSI referenced in this document are available on 
November 23, 2021.

ADDRESSES: Please refer to Docket ID NRC-2020-0214 when contacting the 
NRC about the availability of information regarding this document. You 
may obtain publicly available information related to this document 
using any of the following methods:
     Federal Rulemaking Website: Go to https://www.regulations.gov and search for Docket ID NRC-2020-0214. Address 
questions about Docket IDs in

[[Page 66598]]

Regulations.gov to Stacy Schumann; telephone: 301-415-0624; email: 
[email protected]. For technical questions, contact the individual 
listed in the FOR FURTHER INFORMATION CONTACT section of this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly available documents online in the 
ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``Begin Web-based ADAMS 
Search.'' For problems with ADAMS, please contact the NRC's Public 
Document Room (PDR) reference staff at 1-800-397-4209, 301-415-4737, or 
by email to [email protected]. For the convenience of the reader, 
instructions about obtaining materials referenced in this document are 
provided in the ``Availability of Documents'' section.
     NRC's PDR: You may examine and purchase copies of public 
documents, by appointment, at the NRC's PDR, Room P1 B35, One White 
Flint North, 11555 Rockville Pike, Rockville, Maryland 20852. To make 
an appointment to visit the PDR, please send an email to 
[email protected] or call 1-800-397-4209 or 301-415-4737, between 
8:00 a.m. and 4:00 p.m. (ET), Monday through Friday, except Federal 
holidays.

FOR FURTHER INFORMATION CONTACT: George Alexander, Office of Nuclear 
Material Safety and Safeguards, U.S. Nuclear Regulatory Commission, 
Washington, DC 20555-0001; telephone: 814-415-6755; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction

    The NRC is considering issuance of an amendment of NRC Materials 
License 24-16273-01, issued to Sigma-Aldrich Company, for operation of 
the Fort Mims Site, located in Maryland Heights, Missouri. Therefore, 
as required by Part 51 of title 10 of the Code of Federal Regulations 
(10 CFR), ``Environmental Protection Regulations for Domestic Licensing 
and Related Regulatory Functions,'' the NRC performed an EA. Based on 
the results of the EA that follows, the NRC has determined not to 
prepare an environmental impact statement for the license amendment and 
is issuing a FONSI.
    The revised decommissioning plan was submitted to the NRC, by email 
dated August 22, 2019, and supplemented by a license termination 
request, dated April 27, 2020. On October 19, 2020, an application to 
amend Sigma-Aldrich's decommissioning plan and terminate NRC Materials 
License No. 24-16273-01 was submitted by NRC Form 313 ``Application for 
Materials License.'' In its revised decommissioning plan, the licensee 
requests the option to perform direct dose assessment of residual 
radioactivity, in addition to using derived concentration guideline 
levels (DCGLs), to demonstrate compliance with the license termination 
criteria in 10 CFR 20.1402, at the Fort Mims Site in Maryland Heights, 
Missouri. Under Sigma-Aldrich's license, the licensee shall conduct its 
decommissioning program in accordance with its decommissioning plan. 
The decommissioning plan dated October 22, 2008, states that the 
licensee will rely on the screening values in Appendix H of NRC's 
``Consolidated Decommissioning Guidance: Characterization, Survey, and 
Determination of Radiological Criteria'' (NUREG-1757), Vol. 2, Rev. 1 
to demonstrate that the Fort Mims Site meets the release criteria for 
unrestricted use specified in 10 CFR 20.1402. By letter dated May 12, 
2009, the NRC approved Sigma-Aldrich's decommissioning plan, which does 
not include the use of a dose assessment approach to demonstrate 
compliance. The licensee's commitments in its current decommissioning 
plan include remediating all residual activity to levels below approved 
screening values. The NRC guidance in NUREG-1757, Vol. 2, Rev. 1 allows 
for the use of either the DCGL or dose assessment approach to 
demonstrate compliance with 10 CFR 20 1402. NRC staff is reviewing the 
license amendment requests to revise the decommissioning plan and 
terminate the license concurrently because, if the staff approves the 
revised decommissioning plan and determines that the site meets the 
radiological criteria for unrestricted use under 10 CFR 20.1402, the 
license can be terminated without additional site characterization or 
soil remediation.
    On December 21, 2020, the NRC published in the Federal Register (85 
FR 83109), a notice of opportunity to provide comment, request a 
hearing, and petition for leave to intervene. No comments, requests, or 
petitions for leave were received.

II. Environmental Assessment

Description of the Proposed Action

    The proposed action would approve two requests for license 
amendment. First, Sigma requested the option to perform direct dose 
assessment of residual radioactivity in addition to using DCGLs to 
demonstrate compliance with the radiological criteria for unrestricted 
use in 10 CFR 20.1402 at the Fort Mims Site in Maryland Heights, 
Missouri. The NRC guidance in NUREG-1757, Vol. 2, Rev. 1, allows for 
the use of either the DCGL or dose assessment approach in demonstrating 
compliance with the license termination criteria.
    Second, Sigma also requested license termination based on the site-
specific dose assessment in the revised decommissioning plan and the 
site characterization data referenced in the letter dated April 27, 
2020. Because, according to the licensee, the revised decommissioning 
plan and site characterization data indicate that the site meets the 
radiological criteria for unrestricted use in 10 CFR 20.1402, and, 
therefore, the license could be terminated without additional site 
characterization or soil remediation.
    The proposed action is in accordance with the licensee's 
application dated August 22, 2019, as supplemented on April 27, 2020 
and October 19, 2020.

Need for the Proposed Action

    The proposed action is needed because Sigma was originally approved 
to use screening DCGL values to demonstrate that the entire site meets 
the radiological criteria for unrestricted use specified in 10 CFR 
20.1402. Derived concentration guideline levels are intended to be 
conservative because they are designed to apply generically across a 
range of sites. However, during site characterization, Sigma identified 
areas of contamination exceeding the screening DCGL values. Instead of 
remediating the contaminated soil to less than the screening DCGL 
values, Sigma requested the use of a dose assessment approach in 
addition to DCGLs to demonstrate that the site meets the NRC criteria 
for unrestricted release. The NRC's proposed approval of Sigma's use of 
the dose assessment and DCGL approach instead of the DCGL screening 
values for the site would allow Sigma to use site-specific information 
in a more realistic manner. A license amendment is required for Sigma 
to change their approach from screening DCGLs to the use of a dose 
assessment approach in combination with DCGLs.
    In addition to the request for use of the dose assessment approach 
in combination with DCGLs, Sigma also requested license termination, as 
they have ceased principal activities at the Fort Mims Site. The NRC 
needs to fulfill its responsibilities under the Atomic Energy Act by 
making a decision on the proposed license termination request in a 
manner that would allow unrestricted

[[Page 66599]]

use of the site while protecting public health and safety and the 
environment.

Environmental Impacts of the Proposed Action

    The Fort Mims Site is located within the Lakeside Crossing 
Industrial Park, which is zoned for industrial and commercial use. The 
proposed action would authorize Sigma to adopt a dose assessment 
approach for certain areas of the site to demonstrate compliance with 
the radiological criteria for unrestricted use in 10 CFR 20.1402 and to 
terminate their license. Sigma would use the dose assessment approach 
in combination with DCGLs to evaluate the entire site. The dose 
assessment approach would result in a higher allowed level of residual 
radioactivity in certain areas of the site in comparison to the 
previously approved approach of using screening DCGL values. The use of 
screening DCGL values would require remediation of contaminated soils 
that are present in the areas described in Section 2 of this EA. That 
residual contamination affects the soil and groundwater resources at 
the Fort Mims Site. However, as explained in this notice, the 
radiological and nonradiological impacts from this residual 
contamination would not be significant and the site would meet the 
NRC's requirements for unrestricted use.
    In the Safety Evaluation Report for the Fort Mims Site, NRC staff 
evaluated the dose impacts from the C-14 and H-3 contamination to 
potential future receptors. The staff reviewed the revised 
decommissioning plan, in which Sigma evaluated an industrial worker as 
the likely scenario for the Fort Mims Site. Sigma also evaluated a 
suburban resident scenario, which is plausible but less likely because 
the parcel is currently zoned for commercial and industrial use, which 
is the expected future use for the land as well. In the industrial 
worker scenario, the hypothetical worker is at the site for 8 hours per 
day, does not consume food grown or well water from the site, leaves 
the site after work, and does not work on weekends. In the second 
scenario, the hypothetical suburban resident is at the site for 24 
hours per day and has a vegetable garden but does not consume water 
from an onsite well because of the availability of a public water 
system. The maximum total radiological dose is projected to be 0.0002 
millisievert/year (0.02 millirem/year) for the most likely scenario of 
industrial worker from exposure to site soils. The projected dose to 
the less likely, but plausible, scenario of suburban resident from 
exposure to site soils and food from the garden is 0.038 millisievert/
year (3.8 mrem/year). If groundwater from an onsite well were consumed 
at the Fort Mims Site, the dose would be approximately 0.019 
millisievert/year (1.9 millirem/year) based on: (1) The maximum 
observed groundwater concentrations of C-14 and H-3 in the groundwater, 
and (2) an ingestion rate of 1.4 liter/day (0.37 gal/day). All of these 
potential doses are significantly less than the NRC's unrestricted use 
criterion in 10 CFR 20.1402 of 0.25 millisievert/year (25 millirem/
year).
    Based on its review, the NRC staff determined that the radiological 
environmental impacts from the proposed action for the facility are 
bounded by the ``Generic Environmental Impact Statement in Support of 
Rulemaking on Radiological Criteria for License Termination of NRC-
Licensed Nuclear Facilities'' (NUREG-1496, Vol.1). Because of the 
localized nature of the impacts, the NRC staff does not expect any 
cumulative effects from the proposed action, when considered in 
combination with previously approved actions at the site and other 
past, present, or reasonably foreseeable actions. The total dose from 
the residual radioactivity at the site will continue to be less than 
the 0.25 mSv/y (25 mrem/y) criterion.

Environmental Impacts of the Alternatives to the Proposed Action

    As an alternative to the proposed action, the staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). If 
Sigma is not authorized to use the dose assessment approach to 
demonstrate compliance with 10 CFR 20.1402, then Sigma would have to 
remove the residual radioactivity (by excavating soils) to reach levels 
that are below the previously approved DCGL values, in order to 
terminate their license. Approximately 860 m\3\ (1,100 yd\3\) of soils 
would need to be excavated. Although the residual levels of 
radioactivity in the soils are well below the NRC's criterion for 
unrestricted release of the site, the excavation and removal of this 
material would create a potential for radiological environmental 
impacts. Radiological environmental impacts that could result from such 
remediation activities include inhalation and ingestion hazards to 
workers and the public. As described in the NUREG-1496 and NUREG-1748, 
``Environmental Review Guidance for Licensing Actions Associated with 
NMSS Programs,'' the excavation and removal of soil would also impact 
air quality (dust from excavation), increase noise (earthmoving 
equipment), and affect transportation. These impacts would not be 
significant but, taken together, the potential nonradiological and 
radiological impacts of the no-action alternative would be greater than 
the radiological and nonradiological impacts of leaving the soil in 
place.

Alternative Use of Resources

    The proposed action does not affect any resource implications 
discussed in previous environmental reviews.

Agencies and Persons Consulted

    The NRC staff consulted with the Missouri Department of Natural 
Resources regarding the environmental impact of the proposed action. By 
letter dated August 10, 2021, the State of Missouri provided several 
comments, and the NRC provided a response to those comments. 
Additionally, as described in the NRC's 2009 decommissioning plan 
approval EA, NRC staff previously consulted with the Missouri 
Department of Conservation, Wildlife Division, Endangered Species, on 
March 5, 2009 as required by Section 7 of the Endangered Species Act. 
The purpose of the call was to ensure that the licensing action is 
``not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of the habitat of such species.'' The Missouri Wildlife 
Division staff indicated that, based on their review and knowledge of 
current documents relating to possible endangered species, the 
decommissioning and release of the Sigma building located in Maryland 
Heights, Missouri would not affect any endangered species. NRC staff 
have determined that the current proposed action of allowing dose 
modeling and license termination would not affect listed species or 
critical habitat, because there would be no additional disturbance of 
the site. Therefore, no additional consultation is required under 
Section 7 of the Endangered Species Act.
    As described in the NRC's 2009 decommissioning plan approval EA, 
NRC staff previously consulted with the Missouri Department of Natural 
Resources, as required by Section 106 of the National Historic 
Preservation Act. By letter dated March 19, 2009 from the Department of 
Natural Resource's State Historic Preservation Office, Director, and 
Deputy State Historic Preservation Officer, the State indicated that 
``[w]e have reviewed the information provided concerning the above 
referenced project. Based on this review we concur that the Sigma 
Aldrich Chemical Company is not eligible for inclusion in the National 
Register of Historic Places. In our opinion, the property has been 
extensively disturbed, and there is little

[[Page 66600]]

potential for the occurrence of archaeological sites. We concur that 
there will be no historic properties affected and we have no objection 
to the initiation of project activities.'' NRC staff have determined 
that the current proposed action of allowing dose modeling and license 
termination is not the type of activity that has potential to cause 
effects on historic properties, because there will be no additional 
disturbance of the site. Therefore, no additional consultation is 
required under Section 106 of the National Historic Preservation Act.

III. Finding of No Significant Impact

    Per NRC guidance in NUREG-1757, Vol. 2, Rev. 1, the use of dose 
assessment in combination with DCGLs is an acceptable approach for 
demonstrating compliance with 10 CFR 20.1402. NRC staff also determined 
in its Safety Evaluation Report that the site meets the unrestricted 
use criterion in 10 CFR 20.1402 and that the license can be terminated.
    On the basis of the EA, the NRC concludes that the proposed action 
will not have a significant effect on the quality of the human 
environment. Accordingly, the NRC has determined not to prepare an 
environmental impact statement for the proposed action.

IV. Availability of Documents

    The documents identified in the following table are available to 
interested persons through one or more of the following methods, as 
indicated.

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                                                        ADAMS  accession
                       Document                               No.
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NUREG-1748, ``Environmental Review Guidance for              ML032540811
 Licensing Actions Associated with NMSS Programs''...
NUREG-1757, Vol. 2, Rev.1, ``Consolidated                    ML063000252
 Decommissioning Guidance: Characterization, Survey,
 and Determination of Radiological Criteria''........
Letter from Sigma-Aldrich, regarding Decommissioning         ML083010187
 Plan, dated October 22, 2008........................
Consultation with State of Missouri Department of            ML090640890
 Conservation, regarding Endangered Species, dated
 March 5, 2009.......................................
Letter from State of Missouri Department of Natural          ML090860375
 Resources, State Historic Preservation Officer,
 regarding Sigma-Aldrich, dated March 19, 2009.......
Federal Register Notice--Environmental Assessment for        ML091180638
 Sigma-Aldrich Company's Decommissioning Plan License
 Amendment, dated April 28, 2009.....................
NRC Approval of Sigma-Aldrich Company's Fort Mims            ML091330309
 Facility Decommissioning Plan, dated May 12, 2009...
Sigma-Aldrich Fort Mims Site Revised Decommissioning         ML19273A160
 Plan, dated June 27, 2019...........................
Transmittal Email--Sigma-Aldrich Fort Mims Revised           ML19273A163
 Decommissioning Plan, dated August 22, 2019.........
Sigma-Aldrich Fort Mims Site Request for License             ML20120A544
 Termination, dated April 27, 2020...................
NUREG-1496, Vol.1, ``Generic Environmental Impact            ML20149G542
 Statement in Support of Rulemaking on Radiological
 Criteria for License Termination of NRC-Licensed
 Nuclear Facilities''................................
Sigma-Aldrich Fort Mims Site Revised Decommissioning         ML20294A191
 Plan: NRC Form 313, ``Application for Materials
 License,'' dated October 19, 2020...................
Letter from the State of Missouri Department of              ML21258A322
 Natural Resources, regarding Comments on the Draft
 Environmental Assessment for the Sigma-Aldrich Fort
 Mims Site, dated August 10, 2021....................
Safety Evaluation Report of Revised Decommissioning          ML21300A384
 Plan and License Termination Request for the Sigma-
 Aldrich Fort Mims Site..............................
NRC Response to State of Missouri Department of              ML21277A027
 Natural Resources on Sigma-Aldrich Draft
 Environmental Assessment, dated October 12, 2021....
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    Dated: November 18, 2021.

    For the Nuclear Regulatory Commission.
Randolph W. Von Till,
Chief, Uranium Recovery and Materials Decommissioning Branch, Division 
of Decommissioning, Uranium Recovery and Waste Programs, Office of 
Nuclear Material Safety and Safeguards.
[FR Doc. 2021-25551 Filed 11-22-21; 8:45 am]
BILLING CODE 7590-01-P