NRC INSPECTION MANUAL	IRIB

# PLANT MODIFICATIONS

Effective Date: January 1, 2023

PROGRAM APPLICABILITY:	IMC 2515 A

CORNERSTONES:		Initiating Events	Mitigating Systems	Barrier Integrity

INSPECTION BASES:	See IMC 0308 Attachment 2

# SAMPLE REQUIREMENTS:

*Applicable when the requirements of section 03.03 have been met

# 71111.18-01	INSPECTION OBJECTIVE

01.01	To verify that modifications have not affected the safety functions of important safety systems.

01.02	To verify that the design bases, licensing bases, and performance capability of risk significant structures, systems, and components (SSCs) have not been degraded through modifications.

01.03	To verify that modifications performed during increased risk-significant configurations do not place the plant in an unsafe condition.

01.04 To verify that a site’s SAMGs have been updated when either the Boiling Water Reactor Owners’ Group (BWROG) or the Pressurized Water Reactor Owners’ Group (PWROG) revise generic severe accident technical guidelines.

# 71111.18-02	GENERAL GUIDANCE

NOTE: Potential issues regarding the impact that changes have on Emergency Preparedness and Security (including Cyber Security) should be raised and addressed under their respective Inspection Programs.

Regulatory Guide (RG) 1.187, “Guidance for Implementation of 10 CFR 50.59, Changes, Test, and Experiments,” states that Revision 1 of Nuclear Energy Institute (NEI) 96-07, “Guidelines for 10 CFR 50.59 Evaluations,” provides methods that are acceptable to the NRC staff for complying with the provisions of 10 CFR 50.59. NEI has also published NEI 96-07, Revision 1, Appendix E, “User’s Guide for NEI 96-07, Revision 1, Guidelines for 10 CFR 50.59 Implementation.” However, NEI 96-07, Revision 1, Appendix E, has not been reviewed or endorsed by the NRC. If needed, questions regarding potential 10 CFR 50.59 issues as a result of a licensee’s use of Appendix E can be raised with the DORL PM.

The review of the design aspects of the modification should focus on conformance to relevant design criteria, not the programmatic elements of licensee programs. See Table A, “Inspection Guidance for Parameters Affected by Modification” for additional guidance. Consider inspecting only those parameters which are significant for the particular modification being reviewed. Also, consider informing the regional senior reactor analyst if the plant modification added or deleted functions that could affect the plant specific significance determination process worksheets.

Table A – Inspection Guidance for Parameters Affected by Modification

For each sample, conduct a routine review of problem identification and resolution activities using IP 71152, “Problem Identification and Resolution.”

Licensee’s implemented a voluntary industry initiative (ADAMS Accession No. ML19163A176) to address potential open phase condition concerns identified in Bulletin 2012-01, “Design Vulnerability in Electric Power System” (ADAMS Accession No. ML12074A115) that included either an automatic protection system or manual operator monitoring and actions. If available, licensee modifications to either the automatic protection systems or control room monitoring systems should be selected as samples. [C1]

# 71111.18-03	INSPECTION SAMPLES

NOTES:

1. Inspectors shall use risk informed insights together with other factors, such as engineering analysis and judgment, and performance history, to determine which temporary and permanent modifications will be selected for review.

2. NEI 96-07, Revision 1, Appendix E, shall not be used by NRC staff in evaluating compliance with the provisions of 10 CFR 50.59.

Additonal guidance associated with 10 CFR 50.59 can be found in IMC 0335, “Changes, Tests, and Experiements.”

## 03.01	Temporary modifications.

a. Review the temporary modifications and associated 10 CFR 50.59 screening against the system design bases documentation, including Updated Final Safety Analysis Report (UFSAR) and Technical Specifications (TS). Verify that the modifications have not affected system operability/availability.

b. Verify that the installation of the temporary modifications (if accessible) are consistent with the modification documents. Also, if applicable, verify restoration of the temporary modification (if accessible).

c. Verify configuration control of the modification is adequate by verifying that the plant documents, such as drawings and procedures are updated including adequacy of operating and maintenance procedures.

d. Verify that temporary modifications are identified on Control Room drawings and appropriate tags are placed on equipment being affected by the temporary modifications.

e. Review post-installation test results to confirm that the tests are satisfactory and the actual impact of the temporary modifications on the permanent systems and interfacing systems have been adequately verified by test. Also, if applicable, review planned testing after removal of the temporary modifications.

Specific Guidance

Preference should be given to reviewing modifications as they occur and that occur during at power operations or increased shutdown risk configurations. Selected temporary modifications may include jumpers, lifted leads, temporary systems, repairs, design modifications and procedure changes which can introduce changes to plant design or operations. Although the focus of this inspection is on active modifications, inspectors may choose to review a recently removed temporary modification for adequate restoration and testing. See Table B, “Sample Selection of Temporary Modifications” for additional guidance.

Table B – Sample Selection of Temporary Modifications

Modifications to one system may also affect the design bases and functioning of interfacing systems. In addition, similar modifications to several systems could introduce potential for common cause failures that affect plant risk. For temporary modifications, identification of temporary modifications on drawings and at placement of appropriate tags for equipment being affected by the temporary modification should make operators aware of their impact on the operation of plant equipment and components. The review of the installation (and, if applicable, the restoration from a temporary modification) ensures that the impact on the operation of other equipment is what is expected and previously analyzed, and to verify all other unexpected effects were subsequently evaluated with the results being there is no significant impact on the safe operation of plant or equipment.

The review of the post-installation test results is to ensure that the parent system remains operable and that its safety function has not been impaired. Licensees often use existing procedures, such as surveillance procedures, for post-modification testing. Although performance of existing procedures may have been reviewed by inspectors for other inspectable areas, inspectors should consider the appropriateness of using the existing procedures for validating the modification (as opposed to simply confirming continued operability).

## 03.02	Permanent modifications.

a. Review the design adequacy of the modification.

b. Verify that modification preparation, staging, and implementation does not impair the following:

1. **In-plant emergency/abnormal operating procedure actions**

2. **Key safety functions**

3. **Operator response to loss of key safety functions**

c. Verify that post-modification testing will maintain the plant in a safe configuration during testing.

d. Verify that post-modification testing establishes operability.

e. (Optional) Verify that design and licensing documents have either been updated or are in the process of being updated to reflect the modifications. Verify that significant plant procedures are updated to reflect the effects of the modification prior to being used.

Specific Guidance

Preference should be given to reviewing modifications as they occur and that occur during at power operations or increased shutdown risk configurations. Selected permanent modifications may include permanent plant changes, design changes, set point changes, procedure changes, aging management changes, equivalency evaluations, suitability analyses, calculations, and commercial grade dedications. See Table C, “Sample Selection of Permanent Modifications” for additional guidance.

Table C – Sample Selection of Permanent Modifications

If an optional document and procedure updating review is conducted, examples of design documents which could be affected by modifications are: UFSAR, drawings, supporting calculations and analyses, plant equipment lists, vendor manuals, and PRA models. Examples of significant plant procedures which could be affected by modifications are normal, abnormal, alarm response, and emergency operating procedures, SAMGs, testing and surveillance procedures, and licensed operator training manuals.

## 03.03	SAMG Update (If applicable)

Verify that site SAMGs are updated when the Boiling-Water Reactor Owners Group (BWROG) or Pressurized-Water Reactor Owners Group (PWROG) revise generic severe accident technical guidelines.

Specific Guidance

Licensees have provided commitments that site SAMGs will be updated to future revisions of the BWROG or PWROG generic severe accident technical guidelines, and that the SAMGs will be integrated with other emergency response guideline sets and symptom-based Emergency Operating Procedures, and validated, using the guidance in accordance with processes outlined in NEI 14-01, “Emergency Response Procedures and Guidelines for Beyond Design Basis Events and Severe Accidents.” NEI 14-01, Revision 1, was issued in February 2016 (ML16224A619). Section 3.2 of NEI 14-01 discusses that the the main highlights of the site specific SAMG update process are document development, verification, and validation. Document development entails the licensee assessing the site specific applicability of each strategy presented in the generic severe accident technical guidelines. The licensee should assess the impact of any deviations from the generic severe accident technical guidelines. The licensee verification process should confirm that any referenced equipment, user-aides, supplies, etc. in the updated site specific SAMGs are actually available. The licensee validation process should demonstrate that the updated site specific SAMGs provides the instructions necessary to implement the guidance (i.e. can operators, technicians, etc. actually follow the document). Table top exercises are one way that the licensee may validate site specific SAMG updates.

Licensees have committed to such actions within 2 refueling outages or 3 years (whichever time period is greater) of the publication date of new BWROG or PWROG generic severe accident technical guidelines. The PWROG issued new severe accident technical guidelines in February 2016 (Revision 0), while the BWROG issued a Revision 4 to severe accident technical guidelines guidance in June 2018. A list of the original licensee commitment letters can be found in an Enclosure to a NRC letter titled “Reactor Oversight Process Changes to Address Severe Accident Management Guidelines with Enclosure containing Commitment Letters by Site” (ML16032A029).

# 71111.18-04	REFERENCES

10 CFR 50.59, “Changes, tests, and experiments”

10 CFR 50.69, “Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors”

IMC 0335, “Changes, Tests, and Experiments”

IMC 2515, “Light-Water Reactor Inspection Program - Operations Phase”

IP 71111.17T, “Evaluations of Changes, Tests, and Experiments”

IP 71152, “Problem Identification and Resolution”

NEI 14-01, Revision 1, “Emergency Response Procedures and Guidelines for Beyond Design Basis Events and Severe Accidents,” Feb 2016 (ML16224A619).

NEI 96-07, Revision 1, “Guidelines for 10 CFR 50.59 Evaluations,” Nov 2000 (ML003771157).

NRC Regulatory Guide 1.187, “Guidance for Implementation of 10 CFR 50.59, Changes, Test, and Experiments,” Nov 2000 (ML003759710).

Reactor Oversight Process Changes to Address Severe Accident Management Guidelines with Enclosure containing Commitment Letters by Site (ML16032A029).

RIS 2016-03, “10 CFR 50.59 Issues Identified in NRC's San Onofre Steam Generator Tube Degradation Lessons Learned Report,” April 2016. (ML15196A575)

END

Issue Date: 08/01/22	1	71111.18

Attachment 1 – Revision History for IP 71111.18

Issue Date: 08/01/22	Att1-1	71111.18