AECM-85-0367, Application for Amend to License NPF-29,changing Condition Requiring Resolution of Hydrogen Control Issue Prior to Restart Following First Refueling Outage by Requiring Resolution Schedule to Reflect Final Hydrogen Control Rule

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Application for Amend to License NPF-29,changing Condition Requiring Resolution of Hydrogen Control Issue Prior to Restart Following First Refueling Outage by Requiring Resolution Schedule to Reflect Final Hydrogen Control Rule
ML20151N577
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 12/27/1985
From: Kingsley O
MISSISSIPPI POWER & LIGHT CO.
To: Harold Denton
Office of Nuclear Reactor Regulation
Shared Package
ML20151N580 List:
References
AECM-85-0367, AECM-85-367, NUDOCS 8601030013
Download: ML20151N577 (10)


Text

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MISSISSIPPI POWER & LIGHT COMPANY

] Helping Build Mississippi hetihiilidd5 P. O. B OX 164 0, J AC K S ON, MIS SIS SlP PI 39215-1640 December 27, 1985 O. D. KING $L E Y, J R.

YiCE PREllDENT NUCLE AR OPERAflONS U. S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D. C. 20555 Attention: Mr. liarold R. Denton, Director

Dear Mr. Denton:

SUBJECT:

Grand Gulf Nuc1 car Station Unit i Docket No. 50-416 License No. NPF-29 File: 0260/0756/L-390.0 Proposed Amendment to the Operating License (pCOL-85/24)

AECM-85/0367 Mississippi Power & Light (MP&L) hereby requests by this submittal an amendment to License NPF-29 for Grand Gulf Nuclear Station (GGNS) Unit 1.

This proposed amendment modifies the License Condition requiring resolution of the hydrogen control issue prior to restart following the first refueling outage by requiring, instead, resolution on a schedule which reficcts the requirements of the recently published Final Hydrogen Control Rule. If, following completion of the MP&L research program on hydrogen control, it is determined that plant modifications are required to obtain final NRC approval that an adequate hydrogen control system for the plant is installed, the modifications will be completed on a schedule which is approved by the NRC.

As discussed during the July 29, 1985 meeting with the NRC staff on first refucifng outage items, the attached amendment to License Condition 2.C.(33.d.2) is being requested to allow resolution of the hydrogen control issue generically. In a letter from L. F. Dale to 11. R. Denton dated June 23, 1985. MP&L submitted a proposed schedule for meeting the Final flydrogen Control Rule Requirements which were first published in the Federal Register on January 25, 1985. This proposed nchedule was based on a detailed generic schedule of tasks identified in the Ilydrogen Control Owners Group (llCOG) Program Plan and included completion of plant specific analyses. Because of the inherent uncertainties in this schedule, MP6L believes it is appropriate to modify the present License Condition which requires resolution of the hydrogen control issue prior to startup following the first refueling outage and require, instead, resolution in accordance with the Final Hydrogen Control Rule.

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J16AECM85111301 - 1 Member Middle South Utilities System

AECM-85/0367 Page 2 MP&L is actively working to resolve both the plant specific and generic hydrogen control issues on the best schedule actually achievable and has been responsive to NRC concerns on this issue as discussed in the attachment to this letter.

MP&L has evaluated requesting the IICOG to couplete Crand Gulf specific work on a schedule that will enable MP&L to meet its present license condition; however due to the complexity of the task networks which are de=cribed in detail in the IICOG Program Plan, the' completion of Grand Culf specific work earlier in the program would not accelerate the overall MP&L schedule for resolving the hydrogen control issue. This is due to the integrated schedule developed by the IICOG which consists of both plant specific and generic work.

In many instances completion of generic work is a requirement for initiating plant specific work.

On October 22 1985, in a letter from T. M. Novak to J. B. Richard, the staff stated that the MP&L proposed schedule for meeting the requirements of the flydrogen Rule van unacceptable because it was not consistent with the existing license condition. MP&L hereby proposes an amendment to that license condition and requests that the staff reconsider the proposed schedule submitted in accordance with the Rule on June 23. 1985. This amendment is consistent with the requirements of the Ilydrogen Control Rule by allowing sufficient time for completion of the research program needed to resolve the hydrogen control issue.

A response to this letter is requested by February 28, 1986, to allow MP&L to properly schedule related work activities.

In accordance with the provisions of 10 CFR 50.30. three (3) signed originals and forty (40) copies of the requested amendment are enclosed. The attachment provides the complete technteni justification and discussion to support the requested amendment. This amendment has been reviewed and accepted by the Plant Safety Review Committee (PSRC) and the Safety Review Committee (SRC).

Based on the guidelines presented in 10 CFR 50.92, it is the opinion of HP&L that this proposed amendment involves no significant hazards considerations.

In accordance with the requirements of 10 CFR 170.21. we have determined that the application fee is $150. A remittance of $150 is attached to this letter.

Yours uly.

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ODKabas Attachments: CGNS pCOL-8,/24 cc (See Next Page)

J16AECM85111301 - 2

AECM-85/0367 Page 3 cc: Mr. T. H. Cloninger (w/a)

Mr. R. B. McGehee (w/a)

Mr. N. S. Reynolds (w/a)

Mr. H. L. Thomas (w/o)

Mr. R. C. Butcher (w/a)

Mr. James M. Taylor, Director (w/a)

Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Dr. J. Nelson Grace, Regional Administrator (w/a)

U. S. Nuclear Regulatory Commission .

Region II 101 Marietta St., N. W., Suite 2900 Atlanta, Georgia 30323 c

Dr. Alton B. Cobb (w/a)

State Health Officer State Board of Health Box 1700 Jackson, Mississippi 39205 l

1 1

l 1

I J16AECM85111301 - 3

BEFORE Tile UNITED STATES NUCLEAR REGULATORY COMMISSION LICENSE NO. NPF-29 DOCKET NO. 50-416 IN Tile MATTER OF HISSISSIPPI POWER & LIGilT COMPANY nnd MIDDLE SOUTl! ENERGY, INC.

and SOUTil MISSISSIPPI ELECTRIC POWER ASSOCIATION AFFIRMATION I, O. D. Kingsley, Jr., being duly sworn, stated that I am Vice President Nuclent Operations of Minninsippi Power & !.ight Company; that on behnif of Minninnippi Power I. Light Company, Middle South Energy, Inc., and South Mississippi Electric Power Association I am authorized by Mississippi Power & Light Company to sign and file with the Nucicar Reguintory Commission, thin application for amendment of the Operating License of the Grand Gulf Nucicar Stationi that I nigned this application an Vice President, Nucicar Operations of Mitsinnippi Power 6 Light Company; and that the acntencnts made and the mattern act forth therein are true and correct to th est of my knowledgo, information and belief. g

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O I.* fingnicy /r STATE OF MISSISSIPPI ,

COUNTY OF li1NDS SUBSCRIBED AND SWORN To before me, a Nopgry Public, in and for the County and State above named, this,pgdday of ,jL /> cc u 6/' t , 1985.

( SI'AI.) s a c 0g. > % rd

/ Notary Public s

My comminnion expircut ej er + t t 'n: *

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SUBJECT:

Facility Operating License No. NPF-29, page 11, License l Condition 2.C.(33.d.2) i l' DISCUSSION: It is proposed that the subject license condition be amended to modify the requirement for resolution of the hydrogen control l issue prior to restart following the first refueling outage by requiring, instead, resolution on a schedule which reflects the requirements of the recently published Final liydrogen Control Rule. Should plant modifications be required to obtain NRC approval that an adequate hydrogen control system for the plant is installed, these modifications shall be completed on a schedule which is approved by the NRC. This proposed change to the operating license was discussed during the July 29, 1985 l meeting, in which MP&L met with members of the NRC staff to review and discuss plans for the first refueling outage.

JUSTIFICATION: The subject license condition was incerporated into the Grand Gulf Operating License by the NRC during early efforts to better j understand the hydrogen control issue for Mark III containments. ,

, At the time this licence condition was imposed it was believed l to be adequate and appropriate based on existing programs and schedules in place to satisfy NRC requirements. Since the l

license condition was proposed in 1983 and imposed in 1984, MP&L j efforts in hydrogen control have expanded considerably and new i

insight into the hydrogen combustion phenomenon in a Mark III l containment has led to an extensive test program designed to resolve the hydrogen control issue. The publication of the l

! Final liydrogen Control Rule early this year has for the first I time permitted MP&L as part of the flydrogen Control Owners Group i to submit a schedule that was not only realistic but a schedule I that was based on defined objectives intended to fulfill l established requirements. MP&L believes that the schedule submitted in accordance with the Final liydrogen Control Rule should provide the basis for amendment of the existing License Condition.

On October 2, 1980, the NRC published in The Federal Register

! the first of several proposed interim rules related to hydrogen control. Subsequent to that publication, in a letter dated l

October 30, 1980, the NRC staff advised MP&L that the Commission had decided that the mattnr of hydrogen control for degraded i core accidents in plants with Mark III containments should be l resolved in the near term and not be deferred to rulemaking and l requested that MP&L provide a description of its program to improve hydrogen control capability to cope with significant amounts of hydrogen. MP&L submitted a description of its hydrogen control program on December 9, 1980 and proceeded with the evaluation and design of a hydrogen mitigation system.

Because of the lack of a formal NRC rule or guidance, MP&L was a J14NLSIM85072502 - 2 l

participant in the formation of the Hydrogen Control Owners Group (HCOG) in 1981. One of the purposes of this group was to develop a program plan that would provide guidance for resolving the issue. The first HCOG Program Plan was issued to the NRC on January 15, 1982.

In June of 1982 the NRC issued Supplement 2 to the GGNS Safety Evaluation Report (SER) which concluded that GGNS Unit I could operate safely at power levels not to exceed 5% of full power without the proposed hydrogen control system. On June 16, 1982, the Grand Gulf Operating License, NPF-13, was issued as a low power license and required satisfactory resolution of outstanding concerns regarding hydrogen control in License Condition 2.C. (44)(d) . This license condition required that MP&L provide the necessary technical submittals for justi-fication of interim operation with the hydrogen igniter system (HIS) prior to exceeding 5 percent power. Operation above 5 percent power was contingent upon approval of the HIS.

In SER Supplement 3, issued in July 1982, the staff presented its evaluation of the hydrogen control issue at Grand Gulf and concluded that full-power licensing on an interim basis was acceptable while the final evaluation of this issue was being completed. It was also indicated that the continuing research conducted by both the industry and the NRC into issues relevant to Mark III hydrogen control by deliberate ignition was expected to provide the basis for the final evaluation.

In May 1983, the NRC issued Supplement 4 to the GGNS SER. This report provided an update on the continuing NRC review of the HIS as part of a final evaluation of deliberate ignition. In this report, the staff proposed that MP&L amend its research program on hydrogen control measures to include additional testing and analyses. On the basis of the continuing staff review in this area, it was suggested that License Condition 2.C.(44)(d) be revised to require NRC approval that an adequate hydrogen control system for the plant is installed and will perform its intended function in a manner that provides adequate safety margin prior to startup following the first refueling outage. License Condition 2.C.(44)(d) was subsequently revised and incorporated in the full power amendment (Amendment 13) to the CCNS Facility Operating License NPF-13, issued August 31, 1984. The current GGNS Facility Operating License, NPF-29, has an identical License Condition renumbered to 2.C.(33.d.2),

requiring resolution of the hydrogen control issue prior to startup following the first refueling outage.

It is and has been MP&L's intent to resolve the generic Mark III containment hydrogen concerns through HCOG activities to the maximum extent possible. This generic resolution will provide the basis for the final evaluation of the GGNS HIS except where additional GGNS specific evaluation is needed. MP&L through its L

J14NLSIH85072502 - 3 k .

endorsement of the HCOG research program has committed to continue the analysis and testing required to resolve NRC concerns on the HIS. Significant efforts in the past by MP&L bave led to the development of a computer code for analyses of the Mark III containment response during hydrogen burns, the submittal of substantial analyses specific to Mark III containments and substantial resources provided for generic issue resolution through HCOG. As chairman of the HCOG since the group's inception in 1981, MP&L commits to continue their active role in the ongoing effort to resolve the hydrogen control issue.

The first major testing program initiated on the part of HCOG was the 1/20th scale test program. The objective of this testing program was to qualitatively assess the effects of variations in key parameters that were thought to influence the hydrogen combustion phenomena in preparation for proposed larger scale testing. Based on preliminary results and analysis, HCOG believed that the 1/20th scale test program would ultimately lead to resolution of the hydrogen control issue.

Following analysis of final results and discussion with the NRC, HCOG concluded that results of the 1/20th scale test program were not sufficient to resolve the hydrogen control issue. New concerns required MP&L to take part in an extensive effort to better define the conditions that may prevail during a degraded core accident. The staff concurred that final resolution could not be achieved based on data taken from small scale testing (i.e. 1/20th scale tests) and that MP&L should continue the investigation of hydrogen combustion through testing in a larger facility, such as the proposed quarter scale test facility.

On July 28, 1983 in a meeting between the NRC and HCOG, the NRC staff was notified that HCOG had authorized initiation of the construction phase and completion of the quarter scale Mark III Hydrogen Combustion Test Program. At this time, it was estimated, based on the quarter scale test program scope, that testing would be performed between May and September 1984 and lead to issuance of a final test report by the year's end. As the staff is aware, the program has expanded and unavoidable delays in test facility construction have occurred. The NRC staff has been informed of these increases in scope and schedule delays through HCOG-NRC meetings. Many of the situations in which the scope was expanded resulted from responding to NRC concerns on the quarter scale test program. Significant progress has been made towards resolution of the hydrogen control issue, and the quarter scale test program, though not yet complete, has already enabled the Mark III owners and the NRC to better understand the hydrogen combustion phenomena for postulated degraded core accidents.

J14NLSIM85072502 - 4

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MP&L believed that the requirement for resolution of.the hydrogen control issue prior to startup following the first refueling outage was appropriate and achievable based on information available at the time the License Condition was imposed. Now, with new information available and realistic schedules in place for completion of the quarter scale test program, MP&L believes this requirement is no longer appropriate.

On January 25, 1985, in The Federal Register, the NRC published the Final Hydrogen Control Rule, the first formal regulatory guidance for resolving the hydrogen control issue. This rule requires MP&L to-justify the hydrogen control system for Grand Gulf by completing a suitable program of experiment and analysis

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on a schedule approved by the NRC. The Final Hydrogen Control Rule required MP&L-to submit a proposed schedule for meeting the 3 requirements of the Rule. In a letter from L. F. Dale to H. R.

Denton, dated June 23, 1935, MP&L submitted a proposed schedule for meeting these requirements. This proposed schedule is based on a detailed generic schedu.'e of tasks identified in the HCOG Program Plan and includes completion of plant specific analyses.

This schedule projects a program completion date in early 1987.

MP&L believes that this proposed schedule is sufficient to ensure that a hydrogen control system providing adequate safety margins exists for Grand Gulf. MP&L also believes that it is

- appropriate to modify the present License Condition requiring resolution of the hydrogen control issue prior to startup following the first refueling outage (scheduled to be a 13 week outage starting on June 1, 1986) and instead require resolution in accordance with the Final Hydrogen Control Rule. The formal

-regulatory guidance for resolving the hydrogen control issue should be used to establish the basis for the proposed amendment to the existing license requirement. Hence, MP&L proposes that the hydrogen research program be completed on a schedule which reflects the requirements of the recently-published Final C Hydrogen Control Rule and that any required plant modifications be completed on a schedule approved by the NRC.

By letter dated October 22, 1985 from T. M. Novak to J. B.

~

Richard, the staff s6ated that the MP&L proposed schedule for meeting the Commissicn's rule on hydrogen control systems was unacceptable because it was not consistent with existing license condition 2.C.(33.d.2) of the Facility Operating License. MP&L has given consideration to having work relevant to Grand Gulf completed by HCOG on a schedule that will enable MP&L to meet its license condition, but because of the nature of the generic effort, completing Grand Gulf specific work earlier in the program will not accelerate the overall schedule. MP&L requests that the staff approve the proposed amendment to this license condition and reconsider the proposed schedule submitted on June 23, 1985 for meeting the final Hydrogen Control Rule requirements.

J14NLSIM85072502 - 5

.i s - ,

SIGNIFICANT HAZARDS CONSIDERATION:

The staff's evaluation as referenced in the May 1983 Grand Gulf Safety Evaluation Report, Supplement No. 4, provided the basis for concluding that the hydrogen ignition system for Grand Gulf was acceptable for an interim period. Although test results and analyses in Supplement 5 to the GGNS SER suggested that more severe thermal conditions may exist in the containment than previously considered, preliminary results from the quarter scale test program indicate that those test results and analyses were overly conservative due to the lack of applicability to the Mark III containment.

The technical evaluation of whether or not the proposed amendment involves significant hazards consideration is centered on the three standards of 10CFR 50.92(c). These are whether the amendment will:

1) involve a significant increase in probability or consequences of an accident previously evaluated;
2) create the possibility of a new or different kind of accident from any accident previously evaluated; or
3) involve a significant reduction in margin of safety.

The hydrogen ignition system (HIS) is designed to mitigate the consequences of a severely degraded core and its use or design is not related to those design basis accidents as discussed in the FSAR.

This proposed change to the operating license does not involve a significant increase in the probability or consequences of an accident previously evaluated. The amendment does not involve a ,

change to either the hardware,. logic or procedures that would l result in an effect on the probabilities or consequences of accidents as previously analyzed in the FSAR. MP6L has pre-viously demonstrated that the essential equipment is likely to survive the high temperature associated with hydrogen combustion to assure that a safe shutdown condition may be reached and maintained. .The results of the quarter scale test program are, at worst, expected to lead to very few minor modifications to further Aarure equipment survivability. The quarter scale test program and other analyses being completed as part of the HCOG program are therefore expected to be a con-firmation of existing analyses and conclusions on the adequacy of the installed hydrogen ignition system. Since accidents leading to severely degraded core that would require the use of the hydrogen ignition system are of such low probability, delaying such confirmation of the adequacy of the installed system until after the HCOG program is complete will not significantly alter the probability of an accident nor would it increase the consequences of previously evaluated accidents.

J14NLSIM85072502 - 6

. (f' The proposed change to the operating license does not create the possibility of a new or different kind of accident from any accident previously evaluated. The amendment does not involve a change to either the hardware, logic or procedures that would create the possibility of a new or different kind of accident from any accident previously evaluated. By delaying the final resolution of the hydrogen control issue, the proposed amendment cannot create the possibility of a new or different kind of accident from any accident previously evaluated. Also, the results of the quarter scale test program and other analyses being completed as part of the HCOG program are expected to be confirmatory in nature.

The proposed change will not involve a significant reduction in the margin of safety. The proposed change merely continues operation with the present hydrogen ignition system pending confirmation of adequacy for certain severe thermal conditions.

No margin of safety is affected and the proposed change does not involve a relaxation of the criteria used to establish the safety limits, the bases for limiting safety system settings, the bases for limiting conditions of operation, a change to technical specifications or a change in plant operation.

Therefore, extending this interim period from the end of the first refueling outage to a schedule established for meeting the Hydrogen Rule Requirements which is acceptable to the NRC does not involve a significant hazards consideration.

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