ML20247K504

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Proposed Tech Specs Pages Revising New Program 5.5.18 to Extent That Items B,C & D. Refer to LCO Action Statement & Bases Insert for New Required Actions B.5.1 & B.5.2
ML20247K504
Person / Time
Site: Vogtle  Southern Nuclear icon.png
Issue date: 05/15/1998
From:
SOUTHERN NUCLEAR OPERATING CO.
To:
Shared Package
ML20247K494 List:
References
NUDOCS 9805220114
Download: ML20247K504 (4)
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Prcgrams and Manuals 5.5 5.5 ,Progr,ams and Manuals 5.5.17 Containment Leakaae Rate Testina Proaram (continued)

The provisions of SR 3.0.2 do not apply to the test frequencies specified in the Containment Leakage Rate Testing Program.

The provisions of SR 3.0.3 are applicable to the Containment Leakage Rate Testing Program.

5.5.18 Configuration Risk Manaaement Proaram The Configuration Risk Management Program (CRMP) provides a proceduralized risk-informed assessment to manage the risk associated with equipment inoperability. The program applies to technical specification structures, systems, or components for

.which a risk-informed allowed outage time has been granted. The program shall include the following elements:

a. Provisions for the control and implementation of a Level 1 at power internal events PRA-informed methodology. The assessment shall be capable of evaluating the applicable plant configuration.
b. Provisions for performing an assessment prior to entering the LCO Condition for preplanned activities.
c. Provisions for performing an assessment after entering the LCO Condition for unplanned entry into the LCO Condition.
d. Provisions for assessing the need for additional actions after the discovery of additional equipment out of service conditions while in the LCO Condition.
e. Provisions for considering other applicable risk significant contributors such as Level 2 issues and external events, qualitatively or quantitatively.

l Vogtle Units 1 and 2 5.0 27 Amendment No- (Unft 1)

" Amendment No. (Unit 2) 9905220114 990515 4 ADOCK O gDR .

AC Sources - Operating B 3.8.1 BASES ,

i ACTIONS B.5.1 and B.5.2 (continued)

If the combined reliability of the enhanced black-start CTGs has not been demonstrated or maintained 2 95%, the option of starting and ~unning any one of the six CTGs while in Condition i ts available in the form of Required Action B.5.2. In the event of preplanned maint< .mce that would exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, any one of the six CTGs nu.;t be started prior to entry into Condition B and allowed to run for the duration of Condition B. Otherwise, any one of the six CTGs must be started within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (tad allowed to run) after entry into Condition B if the DG is to be out of service for more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Note that Required Action 8.5.1 requires that one of the two enhanced black-start CTGs be started, but any one of the six CTGs could be started to satisfy Required Action B.S.2. Since a CTG is started and running while the DG is inoperable, it is not necessary that {

the CTG have enhanced black-start capability.

flit The availability of the SAT provides an additional AC source which permits operation to continue for a period not to {

exceed 14 days from discovery of failure to meet the LCO. 1 In Condition B, the remaining OPERABLE DG and offsite circuits are adequate to supply electrical power to the onsite Class IE Distribution System. The 14 day Completion l Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and the low probability of a DBA occurring during this period.

In addition, the Configuration Risk Management Program (CRMP) is used to assess changes in core damage frequency resulting from applicable plant configurations. The CRMP uses the equipment out of service risk monitor, a computer based tool that may be used to aid in the risk assessment of on-line maintenance and to evaluate the change in risk from a component failure. The equipment out of service risk monitor uses the plant probabilistic risk assessment model to evaluate the risk of removing equipment from service (continued) l Vogtle Units 1 and 2 B 3.8-10a Revision No.

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- ATTACHMENT SNC POSITION REGARDING PRA QUALITY i

l The protiabilistic risk analysis, provided as an informational supplement to the deterministic

. justification for the proposed Emergency Diesel Generator Extended Allowed Outage Time (DG AOT), was performed by SNC PRA engineers with limited contractor support. The analysis was I based on both existing and new analyses. ' A description of these analyses, along with the controls .

used for assuring the quality of results are described as follows:

1 The quality standards used in the development of the PRA supporting the IPE are described in detail in Section 5," Utility Participation and Internal Review Team", of the IPE submittal and are summarized as follows:

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- Independent reviews ofIPE Notebooks were performed by Westinghouse and Fauske l

& Associates.

- Technical Reviews were performed by the SNC PRA Group and plant site personnel.

- The PRA documentation notebooks, which stand alone with respect to the information contained, and the analysis which support the notebooks were prepared, reviewed and approved by fully qualified individuals. These notebooks and calculations were developed as quality documents and are retained for the life of the plant.

- The Independent Review Group (IRG) and the IRG consultant, PLG, Inc., provided a peer review. The purpose of the IRG was to provide a critical review of the IPE plan, results, and documentation by experienced personnel from diverse areas of plant expertise. This effort provided considerable confidence that the results and conclusions of the IPE were applicable and representative of the plant.

  • The Conversion of the PRA developed in support of the GL 88-20 IPE Submittal:

The subject conversion transposed the original linked event tree methodology (based on

' Westinghouse software) to a linked fault-tree approach (based on the EPRI CAFTA sertware).' The conveision to CAFTA was ajoint SNC and Science Applications,Inc.(SAIC) project conducted under quality standards defined by SAIC procedures. The converted model was predicated on the original model and accordingly incorporated the assurances of quality which were a pait of the original developmental work described above. The scope of the additional quality assurance effort undertaken included those portions of the modeljudged to involve tasks unique and material to the conversion process such as, any manual conversion of models, enhancements to the model, validation of results against the original PSA, and so

- forth. One such major enhancement to the converted model was incorporation of the alternate source of AC power from the nearby combustion turbine generating station, Plant

. Wilson. The conversion process (including the calculations originated, reviewed, and i approved by fully qualified in3ividuals) is documented in notebooks which were developed j as quality documents and are to be retained for the life of the plant.

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  • ATTACHMENT SNC POSITION REGARDING PRA QUALITY
  • The PSA calculations performed to support the DG Extended AOT:

The DG AOT calculations were performed in accordance with SNC procedures including REES 2-6," Performance of Risk-Based Analysis (RBA)". In accordance with this procedure, RBAs are originated and reviewed by fully qualified engineers assigned by SNC departmental management. The designated originator ensures that the model utilized has been proper:y developed, controlled, documented in accordance with other SNC departmental procedures, and is conducted on a computer which has been verified to produce accurate results for the model selected. The reviewer in turn confirms that the RBA: is free of errors; accurately represents the issue under consideration; utilizes an appropriate approved PRA model; is based on technically sound judgment; and is properly documented. The reviewer, if ,

deemed appropriate, can expand the scope of the review. An RBA is considered a QA record I and is maintained in departmental files for a period of ten years following completion of the analysis.

The conversion model has been reviewed and found to be acceptable for use. Formal l l documentation of the conversion model is complete. The process described above provides an acceptable degree of assurance that the PRA calculations were performed at a level of quality adequate for their intended purpose -- that is in supplemental support of the deterministic justification of the DG AOT extension.

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