ML20195C763
| ML20195C763 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 06/01/1999 |
| From: | Geoffrey Edwards PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-96-003, IEB-96-3, NUDOCS 9906080294 | |
| Download: ML20195C763 (3) | |
Text
C .-
l (tztion support o.partment l
+ A NRCB No. 96-03 I 7 10CFR50.54(f)
PECO NUCLEAR ecco % c -
A Unit of PECO Energy
, hc sp g am 1 June 1,1999 Docket No. 50-353 License No. NPF-85 I
U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
Subject:
Limerick Generating Station, Unit 2 Supplemental Response to NRC Bulletin 96-03, " Potential Plugging of Emergency Core Cooling Suction Strainers by Debris in Boiling Water Reactors"
Dear Sir / Madam:
On May 6,1996, the NRC issued Bulletin 96-03," Potential Plugging of Emergency Core Cooling i Suction Strainers by Debris in Boiling Water Reactors," requesting that addressees implement !
l appropriate procedural measures and plant modifications to minimize the potential for clogging of Emergency Core Cooling System (ECCS) suppression pool suction strainers by debris !
l generated during a Loss-of-Coolant-Accident (LOCA).Bulletin 96-03 also required that all addressees submit written reports discussing the specific actions that will be taken, and when the actions have been completed.
By letter dated November 1,1996, PECO Energy responded to Bulletin 96-03 for Limerick Generating Station (LGS), U .s 1 and 2. In our response, we discussed specific details regarding the plant modifications and associated actions that would be implemented at LGS in response to this Bulletin.
Bulletin 96-03 also required that within 30 days of completion of all requested actions, a written report be submitted confirming completion and summarizing the actions taken. Accordingly, this letter serves to notify the NRC that PECO Energy has completed the installation of new large-capacity, passive strainers on the Residual Heat Removal (RHR) and Core Spray (CS) system pump suction lines at LGS, Unit 2. This modification work was performed during the last Unit 2 refueling outage (2R05) which was completed on May 25,1999. The new strainers have been sized to provide adequate surface area to ensure operability of the ECCS pumps, and therefore, will assure that the ECCS can perform its intended safety function and minimize the need for operator action to mitigate the consequences of a LOCA. The size and shape of the new strainers wit! preclude a loss of net positive suction head (NPSH) for the ECCS pumps due to I
debris accumulation on the strainers following a LOCA. g jo.
9906060294 990601 9 "l PDR ADOCK 05000353 of G PDR ^
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. , Jun21,1999 Page 2 As previously discussed in our letter dated November 1,1996, and reiterated in supplemental correspondence conceming Bulletin 96-03, new stralners were not installed on the Unit 2 High Pressure Coolant injection (HPCl) system pump suction line, since the HPCI system does not function to provide long-term cooling capability following a LOCA. In addition, the primary source for suction supply for HPCI is the Condensate Storage Tank (CST) and not the
- Suppression Pool.
Furthermore, as documented in our letter dated April 3,1997, PECO Energy discussed the -
interim monitoring program that was developed and implemented to ensure ECCS operability pending installation of the replacement strainers. We also discussed our intentions with regard to discontinuing some aspects of the monitoring program following installation of the new strainers. Specifically, the following portions of the program will be discontinued for Unit 2:
. Sampling of water ano sludca material for the presence of fiber.
. Measurement and trending of ECC5 pemp differential pressure (dP) data. This also includes the measurement and trending of Reactor Core isolation Cooling (RCIC) system pump dP data as previously comnnded in our letter dated October 6,1995.
)
PECO Energy has completed the requested actions associated with Bulletin 96-03 for LGS, Unit
- 2. We do not believe that any additional actions are necessary at this time, and that we have achieved long-term resolution of the Bulletin. We will continue to implement our Foreign Material Exclusion (FME) program controls. Suppression Pool and strainer inspections and cleaning will be performed as previously committed in our April 3,1997, letter. Therefore, we are requesting closure of Bulletin 96-03 for LGS, Unit 2. This letter is being submitted under affirmation, and the required affidavit is enclosed.
If you have any questicas or require additionalinformation, please do not hesitate to contact us.
Very truly yours, m ~A Garrett D. Edwards Director- Licensing cc: H. J. Mdler, Administrator, USNRC, Region I (w/ enclosure)
A. L. Burritt, USNRC Senior Resident inspector, LGS (w/ enclosure)
Enclosure i
COMMONWEALTH OF PENNSYLVANIA :
- ss.
COUNTY OF CHESTER :
J. J. Hagan, being first duly swom, deposes and says:
That he is Senior Vice President of PECO Energy Company; that he has read the foregoing supplemental response to NRC Bulletin 96-03, " Potential Plugging of Emergency Core Cooling Suction Strainers by Debris in Boiling Water Reactors," for Limerick Generating Station, Unit 2, and knows the contents thereof; 7 xi that the statements and matters set forth therein are true and mrrect to the best of his knc..vledge, information, and belief.
I I
S ior V Presi@nt Subscribed and swom to before me this N day 1
of dou C , 1999.
044.-Q ud ~
0 / 0 Notary Public Notartal Seal nn'T .d eICo My Comfrussion Expires Dec.18.b Member. Pennsylvania Association of Notarms 1
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