IR 05000352/1987008

Discusses Safety Insp Rept 50-352/87-08 on 870310-12. Details of Specific Observation Re Inconsistencies in Transient Response Implementation Plan Procedure T-116 Encl for Assistance in Developing Committed Revs

ML20237G033
Person / Time
Site:	Limerick
Issue date:	08/07/1987
From:	Johnston W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	Gallagher J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
References
NUDOCS 8708210652
Download: ML20237G033 (4)

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, AUG ? 1981 l 1 Docret No. 50-352 Philadelphia Electric Company ,

ATTN: Mr. J. W. Gallagher  !

Vice President - Nuclear Operations 2301 Market Street i Philadelphia, Pennsylvania 19101 l

Gentlemen:

j Subject: Inspection Report No. 50-352/87-08 Tnis refers to the routine safety inspection conducted by Mr. C. Petrone of l this office on March 10-12, 1987, at Limerick Generating Station, Limerick,

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Pennsylvania of activities authorized by NRC License No. NPF-39 and to the discussions of our findings held by Mr. Petrone with Mr. J. F. Franz and other mer.be's of your staff at the conclusion of the inspection.

! One of the specific observations on Transient Response Implementation Plan Procedure T-116 har been developed in some detail by the reviewer, Mr. Mendiola. It is enclosed for your consideration as you proceed through the committed revisions to these procedures.

, No .eply ta this letter is require Your cooperation with us in this' matter l is appreciated.

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Sincerely, Origimi Signed By-Iee H. Esttenbrenn William V. Johnston, Acting Director Division of Reactor Safety Enclosure: Attachment 1, Inconsistencies in Procedure T-116

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John S. Kemper, Senior Vice President, Engineering and Production G. Leitch, Nuclear Generation Manager J. Franz, Manager Limerick Generating _ation Troy B. Conner, Jr. , Esquire Eugene J. Bradley, Esquire, Assistant General Counsel W. M. Alden, Enaineer in Charge, Licensing Section Public Document Rocm (PDR)

Local Public Document Room (LPDR)

l Nuclear Safety Information Center (NSIC)

NRC Resident Inspector Commonwealth of Pennsylvania g

0FFICIAL RECORD COPY LIMERICK 87-08 - 0001. /07/87 g/

W 8708210652 B70B07 PDR h 0 ADOCK 05000352 l PDR

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. Philadelphia Electric Company 2 l

l bec w/ encl: i Region I Docket Room (with concurrences) -

Management Assistant, DRMA (w/o encl)

Section . Chief, DRP

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Robert J. Bores, DRSS i Lee H. Bettenhausen, DRS A. J. Mendiola, NRR/0LB l W. H. Regan, NRR/HFAB l J. N. Hannon, NRR/0LB

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i RI:DRS p nhausen/djh fl/87 0FFICIAL RECORD COPY LIMERICK 87-08 - 0001. /07/87

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, ATTACHMENT 1 INCONSISTENCIES IN T-116 PROCEDURE R

A concern with T-116 involves steps RF-2, RF-3, and RF-4. These steps involve the opening of the Safety Relief Valves (SRV) to provide a vent flow path to allow for RPV floodin Step C6-1 of the General Electric Owners' Group l Guidelines states in Contingency #6 (RPV Flooding), ~

If at least [3 (Minimum number of SRVs Required for Emergency Depressuriz-ation)] SRVs can be opened or if HPCS or motor driven feedwater pumps are available for injection, close the MSIVs, main steam line drain valves, IC, HPCI, RCIC and RHR steam condensing isolation valve ;

Steps RF-2 and RF-3 of T-116 correspond to this contingency step by stating, RF-2 Can 3 or more SR"s be opened? (YES/NO)

RF-3 (If RF-2 is yes) Open 3 or more SRVs and close the following valves:

MSIVs MS Drains HPCI Steam Line Isolation i RCIC Steam Line Isolation RHR Steam Condensing Isolation In step RF-4 of T-116, which the operators would perform if 3 or more SRVs l cannot be opened, l RF-4 (If RF-2 is no) Provide an Alternate Vent Flow Path with one or i more of the following:

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One or Two SRVs i

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Main Steam to Turbine Bypass Main Steam Drains l HPCI Steam Line via Turbine to Suppression Pool RCIC Steam Line Via Turbine to Suppression Pool  ;

Head Vents According to plant personnel, this step was added by Limerick in case no more than three of the fourteen available SRVs could be opened. With this step, the i operators have the option to open various combinations of these Alternate Vent i Flow Paths, or even all of them. The net result is that they will have opened l some or all the valves that the Owners' Group Guideline Step Cl-6 would have l close In addition, the question of equivalency is raised. If the intent of this step, as stated by plant personnel, is to provide an alternate vent flow .

path equivalent to 3 or more SRVs, could some of the possible combinations of '

valve openings be inadequate for this purpose? What combinations are adequate?

How many is enough?

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OFFICIAL RECORD COPY LIMERICK 87-08 - 0002. /07/87 I

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. 2 The question of equivalency is further compounded later in the procedure. For an example, imagine that for some reason, less than three SRVs can be opened, some of the control rods are still out, and RPV level cannot be determined with any reliabilit Using T-116, the operators provide an Alternate Vent Flow Path with step RF-4 and because some of the rods are still out, they must use the RF-6 through RF-10 logic leg of T-116 to flood the RP Steps RF-8 and RF-9 have the requirement, Maintain RPV pressure above the Minimum Alternate RPV Flooding Pressure but as low as possible by throttling injectio The operators determine the Minimum Alternate RPV Flooding Pressure using a small table adjacent to the steps on the T-116 flow diagra However, the table lists the Minimum Alternate Flooding Pressure by the number of open SRVs. In the example above, a combination of valves is open (SRVs and/or other valves) and the operators will have no idea of what is their Minimum Alternate Flooding Pressure. Furthermore, if the operators had only one SRV valve open I af ter performing step RF-4, there is no Minimum Alternate Flooding Pressure  !'

liste It is also conceivable that af ter performing RF-4, that the operators have opened two SRVs and a combination of various valve Whan they reach Step RF-8, because of the two open SRVs, the operators determine their Minimum '

Alternate Flooding Pressure to be 520 PSIG. If the other valves which were opened in RF-4 were equivalent to two or three SRVs, the operators would end up rapidly injecting water into the vesse Caution four of T-116 states that a rapid increase in injection ma.y cause substantial fuel damag These inconsistencies should be reconcile I

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0FFICIAL RECORD COPY LIMERICK 87-08 - 0003. i 08/07/87

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