ML25037A132

Enclosure 2: Revised Detail Description and Justification for the Proposed Changes

ML25037A132
Person / Time
Site:	07007004
Issue date:	01/30/2025
From:	American Centrifuge Operating
To:	Office of Nuclear Material Safety and Safeguards
References
ACO 25-0013, EPID L-2024-LLA-0070
Download: ML25037A132 (1)

Text

Enclosure 2 of ACO 25-0013 Revised Detailed Description and Justification for the Proposed Changes Information Contained Within Does ot Contain Export Controlled Information Reviewing Official:

Lori Hawk, A 0 Date:

01 /30/2025 ACO 25-0013 Page 1 of 14 Revised Detailed Description and Justification for the Proposed Changes

[Previously submitted under ACO 24-0035 dated Ma 9, 2024 (ori inal, and revised ACO 24-0077 dated October 17, 202 Detailed Description of Change American Centrifuge Operating, LLC (ACO) is requesting U.S. Nuclear Regulatory Commission (NRC) review and approval of the proposed changes for portions of the American Centrifuge Plant (ACP) License Application and Supporting Documents.

These proposed changes support amending the licensing documentation to provide and clarify exemptions from the requirements of IO Code of Federal Regulations (CFR) 70.24, Criticality Accident Requirements. Specifically, all of the subject exemption requests address only the requirements of IO CFR 70.24 subpart (a) regarding Criticality Accident Alarm System (CAAS) coverage for areas in which special nuclear material is handled, used, or stored. Additionally, general proposed changes are also included within this license amendment that did not warrant the NRC's prior review and approval; however, are provided for completeness to assist in the review efforts. Proposed changes are described below:

LA-3605-0001, License A lication or the American Centri u 0035 and Enclosure 3 of ACO 24-0077 Section 1.1.5.6.5, Criticality Accident Alarm System, was revised to reference Section 5.4.4 of the License Application and to reference that exemptions from the requirements of I 0 CFR 70.24 are documented within Section 1.2.5 of the License Application.

Section 1.2.5, Special Exemptions or Special Authorizations, includes additional exemptions from the requirements of IO CFR 70.24 addressing criticality monitoring as identified in Section 3.10.6 of LA-3605-0003, Section 3.10.4 of LA-3605-0003A, and prepared per Section 5.4.4 of the License Application. As such, the following proposed changes have been made:

° Clarified that the original exemption for transportation, handling, and storage of solid UF6 filled cylinders is specific to the commercial ACP operations.

0 ACO proposes an exemption from the requirements of 10 CFR 70.24 for the handling storage, and transportation of fissile 30-series cylinders used for the High Assay Low Enriched Uranium (HALEU) Demonstration project. Note: The transportation aspect referred to under this exemption request is for on-site transportation following receipt of fissile 30-series cylinders (i.e., feed) from an NRC licensed shipper.

Off-site transportation of :pecial nuclear material is not an authorized activity under the currently described HALEU Demonstration project.

0 ACO proposes an exemption from Criticality Accident~AAS1 coverage when the CAAS or its associated equipment is - out of service and compensatory measures that provide an equivalent risk reduction are in place.

ACO 25-0013 Page 2 of 14 0

ACO proposes an exemption from CAAS coverage for non-fissile material operations (NFMOs).

0 ACO proposes an exemption from CAAS coverage for areas in which a nuclear criticality safety evaluation (NCSE) has evaluated the fissile material operation and determined that a criticality accident is not credible. Conclusions of non-credibility require, at a minimum, that the inventory of 235U in the area is less than 700 grams.

0 _ ACO proposes an exemption from CAAS coverage for storage areas in which the only special nuclear material present is contained in packages defined in 10 CFR Part 71 or s ecificall exem taccordin to 10CFR 71.15.

Sections 1.4.1, American National Standards Institute/American Nuclear Society, (ANSI/ANS) and 1.4.2, American National Standards Institute, were revised to reflect the new section references provided within the LA-3605-0003 and LA-3605-0003A.

Section 5.4.2.1, Non-Fissile Material Operations, was revised to clarify that operations in which the uranium enrichment is less than I weight percent or an inventory of less than 100 grams 235U are termed "non-fissile material operations" and are performed without the need for NCS double contingency controls.

Section 5.4.4, riticality Accident Alarm System Coverage, was revised to clarify that CAAS is required in each area where special nuclear material is handled, used, or stored unless the NRC has granted an exemption from the 10 CFR 70.24 and refers to Section 1.2.5 of the License Application for more details related to the CAAS exemptions.

Section 8.1.1, Nuclear Criticality, was revised to clarify that CAAS is required in each area where special nuclear material is handled, used, or stored unless the NRC has granted an exemption from the 10 CFR 70.24 and refers to Section 1.2.5 of the License Application for more details related to the CAAS exemptions.

Section 8.2, References, was revised to remove a reference that was not used within this chapter.

Chapters 1.0, 5.0, and 8.0 of the License Application also contain grammatical and formatting changes throughout.

NR-3605-0008, Emergency Plan for the American Centrifuge Plant [Enclosure 3 of ACO 24-0035 :

Section 2.2.4, Nuclear Criticality, was revised to clarify that CAAS is required in each area where special nuclear material is handled, used, or stored unless the NRC has granted an exemption from the 10 CFR 70.24 and refers to Section 1.2.5 of the License Application for more details related to the CAAS exemptions.

ACO 25-0013 Page 3 of 14 Sections 2.2.4 and 11.0, References, were revised to delete an old Gaseous Diffusion Plant reference based upon the fact that this portion of the site is undergoing decommissioning activities, as well as correct the year reference related to ANSI/ANS-8.23.

Document also contains grammatical and formatting changes throughout.

LA-3605-0003 Inte e Plant Enclosure 4 of ACO 24-0035 Section 3.10.6, Criticality Accident Alarm System, was revised to clarify that CAAS is required in each area where special nuclear material is handled, used, or stored unless the NRC has granted an exemption from the 10 CFR 70.24 and refers to Section 1.2.5 of the License Application for more details related to the CAAS exemptions. Additionally, this section was revised to reference Section 5.4.4 of the License Application to clarify that the need for CAAS coverage is considered during the NCS evaluation process.

Section 3.10.6.1.1, Cylinder Storage Yard Criticality Accident Alarm System Exemption, was revised to clarify that the previously approved cylinder storage yard CAAS exemption is only applicable to the commercial ACP operation and that the exemption from CAAS requirements for fissile 30-series cylinders used for the HALEU Demonstration project is evaluated in LA-3605-0003A.

The following new sections were added to describe the exemptions documented in Section 1.2.5 of the License Application:

0 New Section 3.10.6.1.2, Criticality Accident Alarm System Out of Service Exemption 0

New Section 3.10.6.1.3, Non-Fissile Material Operations 0

New Section 3.10.6.1.4, Operations for Which a Criticality Accident is Not Credible 0

New Section 3.10.6.1.5, Special Nuclear Material Packaged as Defined in 10 CFR Part 71 Section 3.16, References, added ANSI/ANS-8.1-2014 as used in new Section 3.10.6.1.4.

Document also contains grammatical and formatting changes throughout, and the new sections have been added to the Table of Contents.

LA-3605-0003A Addendum 1 o Centri u e Plant - HALEU Demo Section 3.10.4, Criticality Accident Alarm System, was revised to clarify that HALEU Demonstration has CAAS coverage as required by 10 CFR 70.24 unless the NRC has granted an exemption from the 10 CFR 70.24 CAAS requirements as documented in Section 1.2.5 of the License Application.

ACO 25-0013 Page 4 of 14 The following new sections were added to describe the exemptions documented in Section 1.2.5 of the License Application:

o New Section 3.10.4.1, Criticality Accident Alarm System Exemption, was added which discusses the CAAS requirements of 10 CFR 70.24 and 70.17. Additionally, this section clarifies that requested exemptions specific to HALEU Demonstration are described within and requested exemptions that are explicitly applicable to only the commercial ACP or that apply to both are discussed within Section 3.10.6.2 of LA-3605-0003.

o New Section 3.10.4. l. l, Handling, Storage, and Transportation of Fissile 30-Series Cylinders, was added to describe the exemption for operations involving handling, storage, and transportation of fissile 30-series cylinders for HALEU Demonstration.

o Document also contains grammatical and formatting changes throughout, and the new Section 3.10.4.1 has been added to the Table of Contents.

No changes are being proposed to the currently described commercial ACP or HALEU centrifuge cascade design, authorized uses, or authorized possession limits. Additionally, no changes are being proposed to the American Centrifuge Lead Cascade Facility Materials License that is undergoing NRC's review and approval to terminate.

The proposed changes contained within Enclosures 2 through 5 [of ACO 24-0035] are identified by the following method:

Blue 8trilieaut - Identifies text to be removed Red underline - Identifies text to be added Supplemental proposed changes contained within Enclosures 3 and 4 of ACO 24-0077 are identified by yellow highlight for NRC's ease of review.

Justification ACO 25-0013 Page 5 of 14 The following exemptions from the requirements of 10 CFR 70.24 addressing criticality monitoring are identified in Section 3.10.6 of LA-3605-0003, Integrated Safety Anal sis Summar for the American Centrifuge Plant (Enclosure 4 of ACO 24-0035 ACO 24-0077

, and Section 3.10.4 of LA-3605-0003A, Addendum 1 of the Integrated Safety or the American Centrifuge Plant - HALEU Demonstration (Enclosure 5...Qf

, and prepared in accordance with Section 5.4.4 of LA-3605-or the American Centrifuge Plant (Enclosure 2 of ACO 24-0035,.

10 CFR 70.24, Criticality Accident Requirements, requires that licensees authorized to possess special nuclear material in a quantity exceeding 700 g of contained 235U shall maintain in each area in which such licensed special nuclear material is handled, used, or stored, a monitoring system capable of detecting a criticality that produces an absorbed dose in soft tissue of 20 rads of combined neutron and gamma radiation at an unshielded distance of two meters from the reacting material within one minute.

10 CFR 70.17 allows the Commission, upon application of any interested person or upon its own initiative, to grant such exemptions from the requirements of the regulations in this part as it determines are authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest. The requested exemptions are authorized by law because there is no statutory provision prohibiting the grant of the exemption. The requested exemptions will not endanger life or property or the common defense and security and are otherwise in the public interest for the reasons discussed below.

The CAAS is a standalone system comprised of detectors and annunciators that do not interface with or affect property, defense, or security; therefore, the key requirement for evaluating the 10 CFR 70.24 exemption is that it "not endanger life." The activities that are mandated before and after a criticality event are the same, regardless of how the criticality is detected and personnel notified.

NUREG-1520, Standard Review Plan.for Fuel Cycle Facilities License Applications, Revision 2, Section 5.4.3, states that "an applicant that does not meet applicable guidance in the standard review plan should describe and justify an acceptable alternative to meet the regulations." Section 5.4.3.1.1, states that Regulatory Guide 3.71, Nuclear Criticality Safety Standards for Fuels and Material Fadlities, endorses ANSl/ANS-8 national standards, with some exceptions and qualifications. The NRC endorsement of these standards means that they provide methods and practices generally acceptable to the NRC staff for the prevention and mitigation of criticality accidents. However, application of a standard is not a substitute for detailed NCS analyses for specific operations. This section also states that Regulatory Guide 3.71 endorses ANSI/ ANS-8.3-1997 (reaffirmed in 2003) in full.

ACO 25-0013 Page 6 of 14 ANSI/ ANS-8.3-1997, Criticality Accident Alarm System, Section 4.1.1 states that "installation of an alarm system implies a nontrivial risk of criticality" and Section 4.1.3 states that "the purpose of an alarm system is to reduce the risk to personnel. Evaluation of the overall risk should recognize that hazards may result from false alarms and subsequent sudden interruptions of operations and relocation of personnel."

Each of the exemptions from 10 CFR 70.24 are discussed in more detail below to demonstrate that the change is justified and safe.

A. Handling, Storage, and Transportation of Fissile 30-Series Cylinders ortation of fissile 30-series cylinders as part of the HALEU Demonstration project. NCSE-GEN-001,

Nuclear Criticality Safety Evaluation for Large UF6 Cylinders [Revision 5], provides the requirements necessary to maintain criticality safety for the handling and storage of large UF6 cylinders (30-series and 12-series) for HALEU Demonstration. Also, NCSE-GEN-001 provides an evaluation which demonstrates that the handling, storage, and transportation of solid UF6 filled 30-series cylinders presents a trivial risk of criticality.

The NCSE states that operations involving handling, storage, and transportation of fissile 30-series cylinders shall be provided with CAAS coverage, unless NRC approved CAAS exemption criteria are met; therefore, the 30-series cylinders containing fissile UF6 will continue to be stored and handled within CAAS coverage until an NRC authorized exemption is obtained.

This exemption is based on the conclusion within NCSE-GEN-001 [Revision 5] that the risk of criticality for these operations is trivial and credits the robust design features, conservative evaluation assumptions, and multiple controls.

As discussed in Section 1.2.5 of the License Application, ACO proposes the following basis for the exemption for CAAS coverage not being required for the handling, storage, and transportation of fissile 30-series cylinders as part of HALEU Demonstration because there is a trivial risk of criticality for these operations.

The handling, storage, and transportation of fissile solid UF6 filled 30-series cylinders are based on robust passive design features that are subject to management measures and administrative controls that further ensure cylinder integrity and reliability. The passive design features for 30-series cylinder operations include the robust design of the cylinders and storage array fixtures. The 30-series cylinder is fabricated of fire-resistant materials and is designed in accordance with ANSl N 14.1. As such, 30-series cylinders are designed to not breach during a design basis fire and are resistant to damage from dropping, from contact with other cylinders and ACO 25-0013 Page 7 of 14 structures, and from corrosion. The controls, in combination with the robust design of the 30-series cylinders and the self-sealing nature of UF6 and water at the location of a credible crack or puncture, minimizes the accumulation of moderator within a fissile 30-series cylinder. The storage fixtures used in 30-series cylinder storage arrays are also made of fire-resistant materials and are designed to survive a design basis fire as well as minimize lateral movement of the stored cylinders and elevate the cylinders above the ground/floor.

The administrative controls associated with the handling, storage, and transportation of fissile 30-series cylinders support the passive design features discussed above by requiring periodic inspections of cylinders to identify damage, breaches, corrosion, and leak-related accumulation of fissile materials; limiting UF6 enrichment in the cylinders; prohibiting stacking of cylinders; establishing spacing from other fissile materials or processes; protecting the cylinders from conditions that could cause damage; and protecting the cylinders from conditions that could lead to water intrusion.

The fissile 30-series cylinders for HALEU Demonstration are limited to 5 weight percent 235U.

The NCS analyses relied upon to demonstrate compliance with the double contingency principle and the 10 CFR 70.61 performance requirements are extremely conservative.

Each 30-series cylinder is modeled with significantly more fissile material than what can be present in actual circumstances.

In addition, the base model also eliminates spacing between cylinders in the storage array that could contribute to isolation of adjacent cylinders. This conservative cylinder base model is then employed to evaluate upset conditions for 30-series cylinder operations. Upset conditions for the 30-series cylinder operations are also very conservative including; 1) stacked cylinder upsets modeled a large number of stacked cylinders; 2) water intrusion upsets modeled a greater than credible amount of water entering an impacted cylinder; 3) modeled moderation/reflection conditions were extreme, including fully flooded storage array conditions; 4) interaction upsets modeled two failures instead of one; and finally 5) enrichment upsets modeled beyond credible amounts of higher enriched material in the impacted cylinder. Given the extreme configurations evaluated, and large number of failures required to achieve the configurations, the risk of criticality for 30-series cylinder handling, storage, and transportation is well beyond extremely unlikely.

Therefore, the conservative evaluation of upsets, combined with the robust controls for 30-series cylinder operations, supports a conclusion of a trivial risk of criticality.

ACO 25-0013 Page 8 of 14 The increased vehicular and pedestrian traffic necessary to support CAAS maintenance and calibration requirements would increase the likelihood for fire and impact events for 30-series cylinder operations such that workers would be at a higher risk for injury and exposure relative to the minimal mitigative value produced by the presence of CAAS. Therefore, CAAS coverage is not necessary for the handling, storage, and transportation of 30-series cylinders.

Fu1ther discussions related to this exemption for the HALEU Demonstration are documented within Section 3.10.4.1.1 of LA-3605-0003A (Enclosure 5 of ACO 24-0035 B. CAAS Out of Service Exemption ACO requests an exem~

irements of 10 CFR 70.24 a in which the CAAS is -----out of service and compensatory measures are in place. Without this exemption, it is necessary for ACO to provide 10 CFR 70.50(b) notifications when CAAS is taken out of service, such as to support annual CAAS surveillances or other maintenance activities that require a CAAS outage.

Pursuant to 10 CFR 70.50(b)(2), on August I, 2023, ACO notified the NRC of a pre-planned outage of the CAAS to perform periodic testing (NRC Event#56647).

Compensatory measures were implemented in accordance with Section 5.4.4 of the License Application.

These measures included the following: evacuation of non-essential personnel from the area of concern and the immediate evacuation zone (IEZ) before removing CAAS equipment from service, limiting access into the area; restricting fissile material movement; and the use of Personal Alarming Dosimeters for personnel that must access the area during the CAAS outage. These measures were implemented until CAAS coverage was verified to be operational, and the CAAS declared operable in accordance with approved plant procedures. The event was terminated after completion of the routine periodic testing and pursuant to 10 CFR 70.50(c)(2) on September 28, 2023, ACO submitted (ACO 23-0068) the required 60-day written event report to the NRC.

As evaluated and discussed in Section 5.3.4.4 of the previously approved NUREG-1851,

Safety Evaluation Report for the American Centrifuge Plant [ML062700087] dated September 2006, in the unlikely event CAAS coverage is lost, appropriate compensatory measures will be imposed. The applicant stated in Section 5.4.4 of the License Application that it would plan and document compensatory measures as part of off-normal operation procedures before initiation of operations. Section 5.4.4 of the License Application also indicates that these may include equipment shutdown, limiting access, or halting movement of uranium-bearing material. These compensatory measures satisfy the acceptance criteria in Section 5.4.3.4.3(7) of N UREG-1520. These measures are consistent with usual industry practice and are therefore acceptable to the NRC staff.

ACO 25-0013 Page 9 of 14 The exemption being proposed m Section 1.2.5 of the License Application states as follows:

In the event CAAS or its associated equipment is out of service ACO is exempt from the requirements of 10 CFR 70.24.(ru_ provided that compensatory measures are employed and remain effective until the CAAS has been restored to service.

Plant procedures provide for compensatory measures which include limiting access, halting movement of fissile material, and use of Personal Alarming Dosimeters for personnel who access the area during a CAAS outage. The Personal Alarming Dosimeters used to augment the installed CAAS are evaluated against ANSI/ANS-8.3-1997 and the criteria for use shall be specified in procedures.

Further discussions related to this exemption for the ACP and for HALEU Demonstration are documented within Section 3.10.6.1.2 of LA-3605-0003 (Enclosure 4 of ACO 24-0035, ACO 24-0077 Therefore, ACO proposes that the proceduralized compensatory measures described in the License Application support documentation to "justify an acceptable alternative to meet the regulations" and provide equivalent risk reduction to the IO CFR 70.24 compliant CAAS when implemented prior to CAAS outages. Based on the above discussion, an exemption from IO CFR 70.24 for circumstances in which the CAAS is out of service and compensatory measures are in place is justified. Without this exemption, it is necessary for ACO to provide IO CFR 70.50(b) notifications when CAAS is taken out of service, resulting in unnecessary administrative burden. Additionally, an exemption for CAAS outages when compensatory measures are employed is consistent with Section 4.4.2 of ANSI/ANS-8.3-1997.

NRC has granted a similar exemption to other fuel cycle facilities. Reporting planned CAAS outages results in an administrative burden to both ACO and the NRC with no added value. This exemption will not alter reporting requirements for inadvertent criticality events.

C. Non-Fissile Material Operations NFMOs are controlled such that the enrichment and/or inventory are maintained below the enrichment or fissile mass necessary for criticality. The determination of which operations are fissile versus which operations are non-fissile are made by NCS and includes consideration of normal and credible abnormal upset conditions to ensure the enrichment and/or inventory are maintained below 1 weight percent 235U or below I 00 grams 235U.

Section 5.4.4 of the License Application and Section 5.3.4.4 of the previously approved NUREG-1851, state that NFMOs and areas with less than 700 grams 235U do not require

CAAS under 10 CFR 70.24(a).

ACO 25-0013 Page 10 of 14 NCS has determined that these operations cannot be made critical under normal and credible abnormal conditions at the ACP. For items containing less than 100 grams 235U, this mass is a factor of 7 below the minimum critical mass for uranium enriched to 100 weight percent 235U, regardless of whether the material is optimally moderated and fully reflected. HALEU Demonstration is limited to less than 20 weight percent 235U, providing additional conservatism.

Conversely, CAAS false alarms may result in process di ruption and injury to personnel.

Maintaining a CAAS in NFMO areas may also result in increased occupational exposure to personnel and increased foot traffic in those areas. AN l/ANS-8.3-1997, Section 4.1.3 states that "the purpose of an alarm system is to reduce the risk to personnel" and that "evaluation of the overal I risk should recognize that hazards may result from false alarms and subsequent sudden interruption of operations and relocation of personnel." Since these NFMOs cannot be made critical, there is no tangible risk benefit to requiring a CAAS for NFMO areas. Therefore, this exemption is being proposed in Section 1.2.5 of the License Application for completeness and states as follows:

Non-fissile material operations do not require CAAS coverage. ACO has established a threshold of 1 weight percent or higher enriched 235U and 100 g or more of 235U for determining what evaluation for NCS considerations of planned operations must be performed. Operations in which the uranium enrichment is less than I weight percent or an inventory of less than 100 g 235U are termed "non-fissile material operations" and are performed without the need for NCS double contingency controls. The determination of which operations are fissile versus which operations are non-fissile is made by NCS and may be contained within a NCSE or as a separate document. The determination of an operation being non-fissile includes normal and credible abnormal upset conditions to ensure the enrichment and/or inventory are maintained below 1 weight percent 235U or below 100 g 235U. This I 00 g 235U mass is a factor of 7 below the minimum critical mass, regardless of whether the material is optimally moderated and fully reflected for uranium enriched to 100 weight percent 235U. Based on this, the value is sufficiently low to use as a threshold limit for exemption from CAAS coverage.

Further discussions related to this exemption for the ACP and for HA LEU Demonstration are documented within Section 3.10.6.1.3 of LA-3605-0003 (Enclosure 4 of ACO 24-0035 Similar exemptions have previously been approved by the NRC and are actively used by other fuel cycle facilities for CAAS [

References:

ML19088A101, ML09344l396, ML103410249].

D. Operations for Which a Criticality Accident is Not Credible ACO 25-0013 Page 11 of 14 As stated within Section 5.4.4 of the License Application and confirmed in Section 5.3.4.4 of the previously approved NUREG-1851, CAAS is not required for areas in which an NCSE has evaluated the fissile material o eration and determined that a criticality accident is not credible. The basis for requires that the inventory of the area be less than 700 grams 235U at a minimum. The 700 grams mu inventory is consistent with the subcritical mass limit specified in Table 1 of ANSI/ANS-8.1-2014.

Section 5.4.4 of the License Application and Section 5.3.4.4 of NU REG-1851 further states that areas with less than 700 grams 235U do not require CAAS under 10 CFR 70.24(a).

Therefore, this exemption is being proposed in Section 1.2.5 of the License Application for completeness and states as follows:

CAAS coverage is not required for an area in which an NCSE has evaluated the fissile material operation and determined that a critical it accident is not credible. The basis for requires that the inventor of the area be less than

. The 700 g mu inventory is consistent with the subcritical mass limit specified in Table 1 of ANSJ/ANS-8.1-2014.

The conclusion that a criticality in the area is not credible must be documented in an NCSE per Section 5.4.4 of this License Application.

Further discussions related to this exemption for the ACP and for HA LEU Demonstration are documented within Section 3.10.6.1.4 of LA-3605-0003 (Enclosure 4 of ACO 24-0035, ACO 24-0077 Similar exemptions have previously been approved by the NRC and are actively used by other fuel cycle facilities for areas with less than 700 grams 235U.

[

References:

ML19088A101, ML093441396, ML103410249].

E. Special Nuclear Material Packaged as Defined in 10 CFR Part 71 The transportation requirements of 10 CFR Part 71 serve to limit special nuclear material quantities to shipping configurations, thus providing limitations on geometry and interaction of fissile material. Therefore, the maximum number of containers permitted in each area shall be unlimited for low specific activity packages as defined in 49 CFR 173.403, and the maximum number of other fissile packages in each area must be limited to a criticality safety index (CSI) of I 00, with at least 6 meters 20 feet (20 feet6 meters) between areas. Therefore, the NRC has granted exemptions to 10 CFR 70.24 for areas involving special nuclear material that is contained in packages defined in transportation

requirements of 10 CFR Part 71.

ACO 25-0013 Page 12 of 14 Section 173.403 of 49 CFR defines low specific activity packages as those that do not contain fissile material or are fissile exempt under 49 CFR 173.453. This material has been determined to be exempt from all requirements for the transport of fissile material, justifying the transport of unlimited numbers of such low specific activity containers. The CSI exemption is justified based on the requirements of 49 CFR 176.704(e). Based on the low inherent risk of criticality with such materials, the potential for criticality involving these materials is trivial and therefore will not result in undue hazards to life or property.

As discussed above for NFMO areas, false alarms may result in process disruption and injury to personnel. Additionally, granting an exemption from the requirement for a CAAS represents a savings in cost and occupational exposure required to install, maintain, and calibrate the systems.

Therefore, this exemption is being proposed in Section 1.2.5 of the License Application for completeness and states as follows:

CAAS coverage is not required for storage areas in which the only special nuclear material present is contained in packages as defined in 10 CFR Part 71 or specifically exempt according to 10 CFR 71.15. The maximum number of containers permitted in each area shall be tl-fllimited to the size and basic configuration of the packages on the transport conveyance for low specific activity packages, and the maximum number of fissile packages in each area must be limited to a criticality safety index (CSI) of 100, with at least 6 meters 20 feet (20 feet6 meters) between areas, whether fissile or exempt. Fissile exempt packages as defined in 10 CFR 7 I.15 and fissile material in Part 71 packages are not commingled with each other or other fissile material within a storage area outside of CAAS coverage. The transportation requirements serve to limit special nuclear material quantities to shipping configurations, thus providing limitations on geometry and interaction of fissile material.

Therefore, the potential for criticality involving these materials is trivial and will not result in undue hazards to life or property. The increased vehicular and pedestrian traffic necessary to support CAAS maintenance and calibration requirements would increase the likelihood for fire and impact events for these areas such that workers would be at a higher risk for injury and exposure relative to the minimal mitigative value produced by the presence of CAAS. Therefore, CAAS coverage is not required for storage areas in which the only special nuclear material present is contained in packages as defined in 10 CFR Part 71 or specifically exempt according to 10 CFR 71.15.

Further discussions related to this exemption for the ACP and for HALEU Demonstration are documented within Section 3.10.6.1.5 ofLA-3605-0003 (Enclosure 4 of ACO 24-0035, ACO 24-0077 ACO 25-0013 Page 13 of 14 Similar exemptions have previously been approved by the NRC and are actively used by other fuel cycle faci I ities for material that is contained in packages defined in IO CFR Part 71 or specifically exempt according to IO CFR 71.15 [

References:

ML! 9088A IO I, ML09344l396, and ML I 03410249).

Exemptions for NFMO areas; operations for which a criticality is not credible; areas where material is contained in packages defined in IO CFR Part 71 ; and the handling, storage, and transportation of fissile 30-series cylinders are warranted because the risk of criticality is trivial and there is no risk benefit to requiring a CAAS consistent with Sections 4.1.1 and 4.1.3 of ANSl/ANS-8.3-1997.

Therefore, based upon the above discussions, the requested exemptions are allowed by IO CFR

70. l 7(a) which provides for exemptions that are authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest. The potential for criticality involving the operations listed above is very low (trivial) and will not endanger life or property. Additionally, the proposed exceptions do not impact the common defense and security. The requested exemptions are based on the operating experience of similarly licensed fuel cycle facilities employing similar compensatory measures, and accepted consensus standards.

Implementation of these proposed changes will not impact the design function, or method of performance or controlling design functions, structures, systems, and components, nor will the proposed changes decrease the effectiveness of any program or plan contained in the License Applications and Supporting Documents. Moreover, the proposed changes will not change the assumptions, or change, degrade or prevent actions described or assumed in accident sequences evaluated and described in the Integrated Safety Analysis (ISA) Summary/Addendum I of the ISA Summary for HALEU Demonstration, nor will any Items Relied on for Safety (IROFS) be affected. Therefore, no credible accident sequences could exceed the IO CFR 70.61 performance requirements and the potential exposure to the general public is anticipated to be negligible.

Environmental Considerations ACO proposes that there are no significant environmental impacts associated with the changes proposed in this amendment request. The proposed changes do not meet the criteria in IO CFR 5 I.60(b)(2) since they do not involve a significant expansion of the site, a significant change in the types of effluents, a significant increase in the amounts of effluents, a significant increase in individual or cumulative occupational radiation exposure, or a significant increase in the potential for or consequences from radiological accidents.

Additionally, this amendment request does not impact the transportation related to the receipt of feed material as previously evaluated for the HA LEU Demonstration project as currently described within the License Application and Supporting Documents. Therefore, it is believed that the previously documented Environmental Assessment for the Proposed Amendment of U.S. Nuclear Regulatory Commission License Number SNM-2011 for the American Centrifuge Plant in Piketon, ACO 25-0013 Page 14 of 14 Ohio [ML21085A705] dated June 2021 remains bounded. The 2021 Environmental Assessment states in part:

"NUREG-1834, Environmental Impact Statement for the Proposed American Centrifuge Plant in Piketon, Ohio [ML06125013l Volume I and ML061250101 Volume 2] date published April 2006, estimated that 1,100 feed shipments would be shipped annually to the [commercial] ACP, evaluated that number of shipments, and determined transpo1tation impacts from operation to be small. NUREG-1834 also estimated there would be 2,286 truckloads of construction-related material during the first five years of the [commercial ACP] license, evaluated that number of truckloads, and determined transportation impacts from construction to be small to moderate.

The potential transportation impacts during operation of the HALEU cascade would be due to feed shipments. The HALEU feed material would be shipped in U.S. origin 30-8 series cylinders that have a 2.5-ton capacity. ACO would receive a very small fraction of the estimated feed shipments for the commercial ACP.

The NRC staff evaluated the small number of additional feed shipments when compared to the I, 100 feed shipments evaluated for the full [ commercial] ACP, as well as daily vehicular traffic, and concludes that there would not be a significant impact due to transportation activities from the proposed action.

For the anticipated license amendment request, seeking operation of the HALEU cascade for an additional period of up to I 0-years, ACO estimates that three additional shipments of feed material per year would be necessary to meet the expected level of production. Transport of HALEU product is not expected to occur during the period of continued operation. Considering this small number of feed shipments, when compared to the daily vehicular traffic and the larger number of feed material shipments anticipated for the ACP, the NRC staff does not anticipate a significant impact due to transportation activities during the period of continued operation."

Consequently, a separate supplement to the Environmental Report is not being submitted.

Significance Determination for Proposed Conforming Changes ACO has reviewed the supplemental proposed changes supporting the NRC's request for additional information related to the exemptions from the 10 CFR 70.24 CAAS requirements and the previously provided Significance Determination remains unchanged (Reference 2).