ML20133B205

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Summarizes Results of Containment Sys Branch Review of Tech Spec Problem Sheets Needed for Low Power Operation. No Problem Sheets Identified for Resolution Prior to Operation Above 5% Full Power
ML20133B205
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 04/13/1984
From: Houston R
Office of Nuclear Reactor Regulation
To: Novak T
Office of Nuclear Reactor Regulation
Shared Package
ML19276B572 List: ... further results
References
FOIA-84-459 TAC-54458, NUDOCS 8507200250
Download: ML20133B205 (15)


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April 13,1984 MEMORANDUM FOR:

T. Novak, Assistant Director for Licensing. DL 1

FROM:

R. W. Houston, Assistant Director for Reactor Safety, DSI

SUBJECT:

CSB RELATED INPUT RE: ASSESSMENT OF MISSISSIPPI POWER

& LIGHT'S (MP&L) TECHNICAL SPECIFICATION PROBLEM SHEETS FOR GRAND GULF, UNIT 1 (TACS 54458)

Re ference : Memo from T. Novak to W. V. Johnston et al, dated April 10, 1984 Plant Name: Grand Gulf, Unit'l Docket No.: 50-416 l

Licensing Stage: OL NSSS Supplier: GE Architect Engineer: Bechtel Responsible Branch: LB #2 Responsible Project Manager:

D. Houston Review Branch: CSB: DSI The Containment System Branch (CSB) has completed the review requested under TACS No. 54458. This review involved certain Technical Specifications (TS) problem sheets for the Grand Gulf Nuclear Station, Unit 1, as prepared by MP&L.

The work request was to assign priorities to the CSB related TS problem sheets and to prepare an evaluation for each problem sheet that is needed for low power operation.

The CSB has identified 36 TS problem sheets which are within its scope of responsibility. The following summarizes the results of the CSB effort related to these TS problem sheets:

(1) Resolution of problem sheets needed for low power operation:

MP&L identified problem items 292, 293, and 306. Except for item 306, we concur with the applicant and we did not find any additional problem sheets that fall into this category. Enclosed is our evaluation on the 2 identified items in the recommended format as suggested by the reference memo. We disagree with MP&L with regard to problem sheet 306 needing immediate TS changes.

The principle reason MP&L has put high priority on item 306 is based on a MP&L letter (AECM-83/0449, dated August 9,1983) which proposed that RWCU pump suction valves (G 33-F001, F004, F250, and F251) maximum isolation times be changed from the present TS value of 30 seconds to 42 seconds.

Since the issuance of the MP&L letter, the applicant has been notified by GE that the 30 seconds was used in analyses pertaining to a RWCU system line rupture.

In view of this, MP&L has committed 8507200250 850515 PDR FOIA BELL 84-459 PDR-

W T. Novak to rescind the August 9,1983 submittal with respect to the effected RWCU suction valves.

In essense, the maximum closing times of these valves is 30 seconds in the TS and will stay that way. Therefore, there is no. change to the TS. The other element of item 306 is minor in nature and should be considered a category (3) item for longterm resolution.

(2) Resolution of problem sheets needed prior to authorizing operation above 5% of full power; MP&L identified no problem sheets that apply to this category. However, we find items 20, 69 and 235 need to be resolved, prior to proceeding above 5% power.

(3) We consider the remaining 30 itegs to be low priority.

DL should provide guidance to the ap'plicant on when these items should be resolved. The thirty items afe 4, 12, 19, 31, 67, 68, 107, 126, 127, 128, 140, 144, 166, 167, 169, 170, 171, 172, 209, 230, 231, 232, 240, 252, 260, 269, 276, 294, 320, and 325.

Should you have problems or questions with our assessment please contact us.

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R'. W. Houston, Assistant Director for Reactor Safety, DSI

Enclosure:

As stated cc:

R. Mattson R. Capra D. Hoffman D. Houston L. Kintner F. Miraglia C. Thomas D. Brinkman

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  • O GRAND GULF TECHNICAL SPECIFICATION CHANGES Ti tle: Containment and Drywell Airlock Technical Specifications 4.6.1.3 and 4.6.2.3 Item No.: 292/293 Re ference: MP&L Submittal, AECM-84/0219 (Item 3), dated April 7,1984 The applicant proposed that Technical Specification Surseillance Requirements 4.6.1.3.d.2 and 4.6.2.3.d.2 should be revised to require verification that the seal air flask pressure is greater than or equal to 90 psig rather than the currently required 60 psig.

The basis for this change is that the current Technical Specification 4.6.1.3.d.2/4.6.2.3.d.2 requires veri fying seal air flask pressure to be greater than or equal to 60 psig. Technical Specification 4.6.1.3.d.3/4.6.2.3.d.3, however, requires veri fying that the system pressuro does not decay more than 2 psig from 90 psig within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

Based on this allowable pressure decay rate, the air flask pressure should be changed from 60 psig to 90 psig. This will ensure that the minimum inflatable seal pressure of 60 psig will be maintained for at least 30 days assuming no active air supply. The CSB finds the proposed change to the TS to be acceptable and necessary.

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MEMORANDUM FOR:

Thomas M. Novak, Assistant Director for Licensing Division of Licensing FROM:

R. Wayne Houston, Assistant Director for Reactor Safety Division of Systems Integration

SUBJECT:

ICSB REVIEW 0F PROPOSED TECHNICAL SPECIFICATION CHANGES FOR GRAND GULF -UNIT 1 Plant Name: Grand Gulf-Unit 1 Docket No.:

50-416 TAC Nos.:

54667, 54668, 54670 and 54683 Licensing Status: OL Project Manager:

D. Houston Review Branch: ICSB Review Status: Complete By letter dated April 7,1984, from J. P. McGaughey (Mississippi Power &

Light Company) to H. R. Denton (NRC) and by letter dated April 10, 1984 from J. B. Richard (MP&L) to H. R. Denton, the licensee for Grand Gulf -

Unit 1 proposed changes to the facility's technical specifications. Per your request the Instrumentation and Control Systems Branch (ICSB) has reviewed proposed changes numbered 15, 16, 33, 38 (partial) and 103 from the April 7,1984 letter, and proposed change number 308 from the April 10, 1984 l ett er.

Based on its review of the changes and the justifica-tion provided by the licensee the ICSB finds that the proposed changes are acceptable. Enclosure 1 provides an evaluation of each proposed change.

We would like to point out that proposed changes numbered 15, 16, 33 and 308 have been accepted on an interim basis. These changes involve instrument setpoints and allowable values and are all in the conserva-ti ve di rection.

Contact:

M. Virgilio, ICSB X29454

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T. Novak.

My memorandum to you dated March 20, 1984 provides the status of our re-

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view of the setpoint methodology for Grand Gulf and other BWRs currently under licensing review. The level of detail necessary to confirm the final acceptability of these proposed changes may not be available for B"C

. s ome ti ne. Grand Gulf, along with other members of the GWR Owner's Group, X

are currently in the process of assembling the information required to resolve this issue. Therefore, we will have to confirm the acceptability of the proposed trip setpoints and allowable values at some later time.

e The staff concludes that there is reasonable assurance, based on staff participation in meetings with the BWR Owner's Group working group on setpoint methodology, that the forthcoming more detailed information on setpoints and setpoint methodology being developed by this group will verify the acceptability of the proposed setpoints. contains the SALP input for these evaluations in accordance with Office Letter No. 44. This completes the ICSB portion of TACS 54667, 54658, 54670 and 54683.

R. Wayne Houston, Assistant Director for Reactor Safety Division of Systems Integration

Enclosures:

As stated cc:

R. Mattson R. Capra D. Hoffman L. Kintner D. Houston Dist: AD/RS, F. Rosa, J. Calvo, M. Virgilio, J. Joyce, All Section B Members

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ICSB'S EVALUATION OF THE TECHNICAL SPECIFICATION tHANGES PROPOSED BY MISSISSIPPI POWER & LIGHT COMPANY BY LETTERS DATED APRIL 7, 1984 AND APRIL 10, 1984 1.

April 7, 1984 l

Change #15. Technical Specification Tables 2.2.1-1, 3.3.2-2, 3.3.3-2 and 3.3.8-2 and Bases 2.2.1, 3/4.3.2, 3/4.3.3 and 3/4.3.8.

Proposed Changes 1.

Revise the drywell and containment pressure instrument setpoints and allowable values in the above listed Tables to account for the effects of the worst case negative barometric pressure changes.

2.

Revise the above listed Bases Sections to discuss how the effects of barometric pressure changes on the drywell and containment pressure instruments setpoints have been considered.

Evaluation For the Grand Gulf design, both the drywell and containment pressure instrumentation provide trip signals that are necessary to ensure the capability to prevent or mitigate the consequences of postulated acci-dents.

In addition, the drywell pressure instrumentation also provides trip signals required for achieving safe shutdown. The drywell and containment pressure instrumentation does not automatically adjust the setpoints to compensate for changes in barometric pressure.

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2-The licensee has stated that historical weather information for the plant locale indicates that the largest negative barometric devi-

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ation from standard pressure expected is 0.50 psi. To ensure that the instrument trip setpoint (set during normal barometric pressure

. conditions) are not exceeded during worst case conditions, the licen-see has proposed to reduce the setpoints and allowable values to 0.50 psi.

s The proposed changes to the Bases Sections provide additional informa-tion concerning the effects of barometric pressure changes on the trip setpoints and allowable values for the drywell and containment pressure instrumentation.

The changes to the drywell and pressure instrumentation setpoints and allowable values are considered by the licensee to be temporary. An analysis is in progress to justify the present values, however, as an interim measure the licensee has proposed these more conservative values.

In addition, in response to a request from the NRC staff the licensee is participating in a BWR Owner's Group effort to provide more detailed information on their setpoint methodology. The final acceptability of the Grand Gulf setpoint methodology, trip setpoints and allowable values will be addressed in a supplement to this report.

The staff concludes that there is reasonable assurance, based on staff participation in meetings with the BWR Owner's Group working group on setpoint methodology, that the forthcoming more detailed information on setpoints and setpoint methodology being developed by this group will verify the acceptability of the proposed setpoints.

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April 7,1994 Change #16. Technical Specification Table 3.3.8-2.

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Revise Table 3.3.8-2 to specify the containment high pressure trip setpoint and allowable value at 7.84 psig and 8.34 psig, respective-

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l Evaluation t

In response.to a recommendation from the NSSS vendor (General Electric) the licensee is proposing to revise the containment spray initiation instrumentation setpoint and allowable value. The licensee has stated

' that this change is necessary to correct an error that resulted from a mistake in the: documents on setpoints supplied to the licensee by Gen-eral Electric.

In response to a request from the NRC staff the licensee is partici-pating in a BWR Owner's Group effert to provide more detailed informa-tion on their setpoint reth]dology. The final acceptability of the Grand Gulf setpoint methodology, trip setpoints and allowable values will be addressed in a supplement to this report. The staff concludes that there is reasonable

  • assurance, based on staff participation in meetings.with the BWR Owner's Group working group on setpoint methodology,

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staff finds that the proposed change is in the conservative direc-tiion and is acceptable.

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April 7, 1984 Change #033. Technical Specification Table 3.3.8 and Bases 3/4.3.8.

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Proposed Change Revise Table 3.3.8-2 to specify the containment spray system timers trip setpoints and allowable values at 10.85 and 10.10 minutes and 10.26 - 0.00 + 1.18 minutes, respectively. Footnote the System B j

timer to indicate that System B includes two timers (E12-K0938 and E12-K116) and.that the trip setpoint for E12-K116 is not to exceed 10.00 seconds of the total' 10.85 10.10 minutes.

Revise Bases 3/4.3.8 to discuss the' analyzed minimum and maximum time delays between the enset of accident conditions and initiation of containment sprays.

Evaluation The containment spray system is a subsystem of the residual heat removal RHR system. Two of three RHR trains automatically divert

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5-low pressure coolant injection flow to the core to the containment spray provided certain conditions are sensed by the containment spray initiation logic. Timers are provided within this logic to insure that injection flow is directed to the core for at least 10 minutes.

In reviewing the setpoint calculations the licensee detennined that there is an error in the setpoint resulting from a mistake in determin-P ing the total instrument loop accuracy.

In addition, the licensee dis-covered that the additional 90 second time delay in the initiation of 1

the B is inconsistent with the safety analyses. The licensee has t

stated that the safety analyses are based on simultaneous spray ini-tiation. Accordingly, the licensee has proposed trip setpoints and allowable values to correct the deficiency in summing the instrument loop inaccuracy and remove the 90 second time delay in Train B ini-tiation.

A footnote is proposed to be added to Table 3.3.8-2 to clarify the new trip setpoint for the Systein B timers. This footnote will spe-cify that the present 90 second delay is to be set at a value not to exceed 10.00 seconds.

l' A change-to the bases has been proposed to address the upper and lower time limit associated with containment spray initiation.

In response to a request from the staff the licensee is partici--

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pating in a BWR Owner's Group effort to provide more detailed in-f formation on their setpoint methodology.

The final acceptability 1

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of the Grand Gulf setpoint methodology, trip setpoints and allowable values will be addressed in a supplement to this report. The staff concludes that there is reasonable assurance, based on staff partici-pation in meetings with the BWR Owner's Group working group on set-point methodology, that the forthcoming more detailed information on setpoints and setpoint methodology being developed by this group will verify the acceptability of the proposed setpoints.

In the interim, the staff finds that the proposed chan~ge is in the conservative direc-tion and is acceptable.

4.

April 7, 1984 Change #38 (partial). Technical Specification Tables 4.3.2.1-1, 4.3.7.1-1 and 4.3.7.5-1.

Proposed Change Revise the channel calibration frequency from refueling (R) to annually (A) for the following instrument channels:

1.

Table 4.3.2.1-1 (Pages 3/4 3-20 and 3-21) a.

Item 1.g - Containment & Drywell Ventilation Exhaust b.

Iten 3.c - Fuel Handling Area Ventilation Exhaust l

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Item 3.d - Fuel Handling Area Pool Sweep Exhaust 2.

Table 4.3.7.1-1 (Page 3/4 3-59) l'..

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Item 1 - Component Cooling Water b.

Item 2 - Standby Service Water c.

Item 3 - Offgas Pre-treatment d.

Item 4 - Offgas Post-treatment e.

Item 5 - Carbon Bed Vault f.

Item 6 - Control Room Ventilation g.

Item 7 - Containment and Drywell Ventilation Exhaust h.

Item 8 - Fuel Handling Area Ventilation 1.

Item 9 - Fuel Handling Area Pool Sweep Exhaust i

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Table 4.3.7.5-1 (Page 3/4 3-72) a.

Item 14 - Containment Ventilation

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Item 15 - Offgas and Radwaste Building Ventilation i

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Item 16 - Fuel Handling Area Ventilation

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Item 17 - Turbine Building Ventilation e.

Item 18 - Standby Gas Treatment System A & B Exhaust i

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From a review of the FSAR and the Technical Specifications the li-l censee has found a discrepancy between the commitments contained i

J in the FSAR and the requirements of the Technical Specifications.

The FSAR states that continuous radiation monitoring instruments 4

that are accessible during normal operation and airborne radiation monitors will be calibrated annually.

This is in accordance with the detector manufacturers recommendations.

I Regulatory Guide 1.118 " Periodic Testing of Electric Power and Protection Systems" which endorses IEEE Standard 338-77 "IEEE Standard Criteria for the' Periodic Testing of Nuclear Power Gen-erating Station Safety Systems" provides guidance on the methods to be used in establishing surveillance frequencies. Based on its review, the staff finds that the methods used to determine

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the proposed surveillance frequencies are in accordance with R.G.1.118 and IEEE 338 and 'are more conservative than the

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guidance provided by the STS. Therefore, the staff finds the proposed change acceptable.

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April 7,1984 Change #103. Technical Specification Table 3.3.2-1.

Proposed Change Revise the MINIMUM OPERABLE CHANNELS PER TRIP SYSTEM column of Table 3.3.2-1 from 2 to 8.

Delete footnote 8.

Evaluation t

i For the Grand Gulf design, one of the' signals that initiates main s' eam line (MSL) isolation is high steam line flow. Sixteen main t

steam line flow instrument channels are arranged into two trip systems, each trip system containing two channels per steam line for-a total of eight channels per trip system. To ensure a success path for initiation of MSL isolation, postulating a single failure in the instrumentation system, requires that all eight MSL flow channels in each trip system be operable. Therefore, the licensee has proposed to revise the minimum channels operable requirements of the technical specifications from two per trip system to eight per trip system. Deletion of footnote 8 removes an explanation of the logic configuration associated with the two per trip system requirements.

Based on its review, the staff finds that the proposed changes enhance system relf ability by ensuring a success path given a single failure for the MSL initiation logic through appropriate minimum operable channel requirements. Therefore, the staff finds that the proposed changes are conservative and are acceptable.

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April 10, 1984 Change #308. Technical Specification 3.3.2-2.

Proposed Change Revise the trip setpoints and. allowable values for the following instrument channels:

a) 4.c.1 RWCU Heat Exchanger (HX) Room Temperature-High b) 4.c.2 RWCU Pump Rooms Temperature - High c) 4.c.3 RWCU Valve Nest Room Temperature - High d) 5.d RCIC Equipment Room Ambient Temperature - High e) 5.1 RHR Equipment Room Ambient Temperature-High f) 5.j RHR Equipment Room Delta Temperature-High g) 6.a RHR Equipment Room Ambient Temperature-High h) 6.b RHR Equipment Room Delta Temperature-High Evaluation The licensee has performed re-review of the calculations used to establish trip setpoints and allowable values for the temperature sen-sing instrument channels that provide input to the leak detection isola-tion features of the Grand Gulf-Unit 1 design. From this re-review the licensee has determined that the values are too high to ensure prompt isolation. Using the current Technical Specification values may result in delayed detection or no detection of a 25 gpm leak.

In response to a request from the NRC staff, ttle licensee is parti-cipating in a BWR Owner's Group effort to provide more detailed in-formation on their setpoint methodology. The final acceptability of the Grand Gulf setpoint methodology, trip setpoints and allowable values will be addressed in a supplement to this report. i.ie staff concludes that there is reasonable assurance, based on staff parti-cipation in meetings with the BWR Owner's Group working group on

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setpoint methodology, that the forthcoming more detailed information on setpoints and setpoint methodology being developed by this group will verify the acceptability of the proposed setpoints.

In the interim, the staff finds that the proposed change is conservative and is acceptable.

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