ML20137V118

Summary of 851112-13 Meetings W/Util at Plant Site Re Status of SEP Evaluations & Observation of Mods Made in Response to SEP Issues.Reviews in Progress on SEP Topics III-1,III-2, III-4.A,III-5.A,III-6,III-7.B & VI-4

ML20137V118
Person / Time
Site:	Yankee Rowe
Issue date:	11/25/1985
From:	Clifford J, Mckenna E NRC
To:	NRC
References
TASK-03-01, TASK-03-02, TASK-03-04.A, TASK-03-05.A, TASK-03-06, TASK-03-07.B, TASK-06-04, TASK-3-1, TASK-3-2, TASK-3-4.A, TASK-3-5.A, TASK-3-6, TASK-3-7.B, TASK-6-4, TASK-RR NUDOCS 8512090471
Download: ML20137V118 (5)

Text

. . . . -. . - - - - - - . . . . -

, paun UNITED STATES 4 NUCLEAR REGULATORY COMMISSION

, g i  :; :j wAsmNGTON, D. C. 20555

'*, * . . . . #' November 25, 1985 a

4 Docket No.: 50-029 i

LICENSEE: Yankee Atomic Electric Company FACILITY: Yankee Nuclear Power Station

SUBJECT:

MEETING

SUMMARY

- STATUS OF SEP EVALUATIONS AND PLANT MODIFICATIONS i .

. On November 12-13, 1985, members 'of the NRC staff met with licensee

, representatives at the Yankee plant site to discuss the status of i SEP evaluations, especially the seismic reevaluation program, and to

observe recent plant modifications made in response to SEP issues.

i A list of attendees is provided in Enclosure 1.

The staff, noted that reviews are in progress on the following topics:

t III-1 Classification of Components, Systems (Quality)

III-2 Wind and Tornado Loadings l III-4.A Tornado Missiles

! III-5.A Effects of Pipe Break Inside Containment

! III-6 Seismic Design Considerations III-7.B Design Codes / Load Combinations

- VI-4 Containment Isolation System l For several of these topics, further information is needed; the questions i will be formally issued to the licensee in the near future.

l The status of the seismic evaluation program was the main topic of ,

l discussion for the remainder of the meeting. i The scope, criteria and input motions for the seismic evaluation program  ;

have evolved over the last few years. Clarification of several terms '

l that have been used in the licensee submittals was provided during the l

! meeting.

1 .

Hot Shutdown' Scope - this encompasses all systems, structures, and i components required to . achieve and maintain a safe shutdown condition, 7 j including any items whose failure could impact required equipment.  !

o  :

} . Safe Shutdown System (SSS) Piping - this refers to existing piping in  !

the reactor coolant system, connected piping and piping in the main .

steam /feedwater systems whose integrity is needed to attain safe '

l shutdown and to prevent a major piping system failure. l i

8512090471 851125 9  :

DR ADOCK O

---

,-v%-mm-wn.n w--e-e --g w, #r-ryvw ws--w+-, ---- v-* - -- ry ,=w, we % -*-+ge- wy--e -9.m .,y y-mm-r---,,- ~*---gy,w w . e- yay v+w mr.:s-s e w =,;w -u-ya v +zy r w-9-- ey-y r- urvrv y--

l i

l Dedicated Safe Shutdown System - this refers to the new system that has been installed to provide makeup to the steam generators and to the reactor coolant system.

At this time, the licensee's intention is to qualify existing plant systems and structures required for hot shutdown and the dedicated safe shutdown system.

Plant systems and structures normally used for cold shutdown and accident mitigation would not be upgraded, consistent with the Integrated Plant Safety Assessment Report (IPSAR), NUREG-0825.

Both the licensee and the staff have developed site-specific input spectra for seismic evaluation, which are referred to as the Yankee Composite Spectra (YCS) and the NRC (or LLL/ TERA) site-specific spectra respectively.

The staff does not consider YCS by itself to be a sufficiently conservative representation of the safe shutdown earthquake. However, as discussed in the IPSAR, the YCS earthquake in conjunction with linear-elastic analysis methods and comparison to code design-allowables is an acceptable design basis. A demonstration of no loss of function assuming the NRC seismic input is needed to provide a sufficient safety margin and to confirm the staff's judgement concerning the margin provided by the YCS analysis compared to code design-allowables. Additionally, in some cases the licensee used a no loss of function criteria to compare to YCS analyses. The staff does not feel this comparison is appropriate. Comparison of NRC to function is still needed for these cases.

Thus, in the IPSAR the licensee agreed to perform analysis using both spectra. During the November 12, 1985 meeting the licensee stated that these analyses have been performed for almost all of the structures and systems, except for major mechanical equipment.

The staff and its consultants have been reviewing the licensee's submittals and have raised questions regarding which acceptance criteria were used for the YCS and NRC spectra analysis, as well as questions concerning modeling.

The staff will issue to the licensee the questions that have been generated by its consultants. The licensee agreed to assemble a list of what analyses that have been done, which input spectra and criteria were used, and the results. A meeting among the NRC, YAEC and consultants will then be arranged to resolve these concerns.

For electrical equipment anchorage, the licensee intends to use the Seismic Qualification Utility Group (SQUG) walkdown approach. A similar review was performed in 1983 as part of the EQE evaluation.

For cable trays / raceways, the licensee plans to use the work performed by the SEP Owner's Group.

t The licensee described the approach that was used to determine which masonry walls require qualification and the modifications that have been made to walls in the turbine building. The staff viewed photographs of the work in progress and observed the completed modifications during the plant tour.

7-November 25, 1985 The majority of the large bore piping supports inside the vapor container were installed in a previous outage. Some small bore piping support modifications are being made during the current refueling outage. A licensee representative stated that YAEC plans to use some of the methodology /

criteria endorsed by NUREG-1061, such as PVRC damping, to limit the number of additional pipe supports, using YCS as the seismic input. The staff indicated that the acceptability of this approach needs to be considered in the context of the resolution of the staff's general concern regarding YCS vs NRC spectra analyses.

The dedicated safe shutdown system electrical equipment, piping and instrumen-tation have been installed. A review by the staff of the dedicated system still needs to be conducted. The turbine building scuppers (for flood protection) and the jet impingement shield on the switchgear room wall are also complete.

The licensee reiterated the desire to resolve bcth the seismic and tornado issues as soon as possible so that upgrades to the primary auxiliary building and the main steam /feedwater support structure (among others) can be completed during Summer 1986.

Original signed by: E. McKenna Original signed by: J. Clifford Eileen McKenna, Project Manager James Clifford, Project Manager Systematic Evaluation Program Branch Operating Reactors Branch #5 Division of Licensing Division of Licensing

Enclosure:

As Stated cc: See Next Page , DISTRIBUTION ,

e Doctettme ?

NRC PDR L PDR SEP Reading

-ORB 5 Reading 0 ELD H. Thompson E. Jordan B. Grimes J. Partlow J. Clifford C. Grimes ACRS (10)

E. McKenna J. Zwolinski C. Jamerson SEPBktW SEPB:D ORB #5:DL ORB #5 EMcKenna:lt CGrimes JClifford JZwolinski 11/a)/85 11 @ 85 11/Zf/85 11/t t/85

Mr. George Papanic, Jr.

Yankee Atomic Electric Company Yankee Nuclear Power Station cc:

Mr. James E. Tribble, President Yankee Atomic Electric Company 1671 Worcester Road Framingham, Massachusetts 01701 Thomas Dignan, Esquire Ropes and Gray 225 Franklin Street Boston, Massachusetts 02110 Mr. N. N. St. Laurent Plant Superintendent Yankee Atomic Electric Company Star Route Rowe, Massachusetts 01367 Chairman Board of Selectmen Town of Rowe Rowe, Massachusetts 01367 Resident Inspector Yankee Nuclear Power Station clo U.S. NRC Post Office Box 28 Monroe Bridge, Massachusetts 01350 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 Robert M. Hallisey, Director Radiation Control Program Massachusetts Department of Public Health 150 Tremont Street, 7th Floor Boston, Massachusetts 02111

, Enclosure 1

Meeting with Yankee Atomic Electric Company Attendance List November 12-13, 1985 4

Name Affiliation G. Papanic YAEC J. Kay YAEC J. Hazeltine YAEC ,

S. Fournier YAEC B. Holmgren YAEC J. Clifford NRC

E. McKenna NRC l

?

i 4

4 8

I i

i r

i.

L t

[

i t

,i t

I

' l l i 4

r 9

t

___._..______,__,._.--.._____)