ML20207Q480

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Forwards Safety Evaluation/Analysis Supporting Hydrogen Water Chemistry for Peach Bottom Atomic Power Station Units 2 & 3, Supporting Util Plan to Install Liquid Hydrogen & Oxygen Storage Sys to Reduce Effects of IGSCC
ML20207Q480
Person / Time
Site: Peach Bottom  Constellation icon.png
Issue date: 01/21/1987
From: Gallagher J
PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To: Muller D
Office of Nuclear Reactor Regulation
Shared Package
ML20207Q481 List:
References
NUDOCS 8701270415
Download: ML20207Q480 (2)


Text

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PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 PHILADELPHIA. PA.19101 1215) 841 5001 JOSEPH W. G ALLAGHE R

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January 21, 1987 Docket No. 50-277 50-278 Mr. Daniel R. Muller BWR Project Directorate #2 Division of BWR Licensing U. S. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

Peach Bottom Atomic Power Station Units 2 and 3 Liquid Hydrogen and Liquid Oxygen Storage Systems

REFERENCES:

(1) Letter, J. W. Gallagher, PECo, to D. R. Muller, USNRC, dated December 22, 2986 (2) Letter, R. M. Bernero, USNRC, to G. H. Neils, BWROG, dated February 7, 1986

Dear Mr. Muller:

l The purpose of this letter is to provide information to l NRC concerning Philadelphia Electric Company's plan for installation of a liquid hydrogen and oxygen storage system at i Peach Bottom Atomic Power Station. Philadelphia Electric Company

( is developing a Hydrogen Water Chemistry. program to further improve the reactor water chemistry of Peach Bottom Units 2 and

3. Installation of a hydrogen and oxygen system is required to support this program. The purpose of the program is to reduce l the effects of Intergranular Stress Corrosion Cracking (IGSCC).

l

! Intergranular Stress Corrosion Cracking of austenitic j stainless steel piping in BWRs has resulted in costly plant l outages. Hydrogen Water Chemistry, which consists of the combination of good water chemistry and the addition of hydrogen to the feedwater, has been shown to be effective in arresting l pipe cracking and pipe crack growth. Addition of hydrogen decreases the oxidizing power of the reactor water and reduces its aggressiveness toward plant structural materials.

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Philadelphia Electric Company has prepared a safety i

evaluation supporting the cryogenic storage, vaporization, and gpk B701270415 870121 i PDR ADOCK 05000277 P PDR

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Mr. D:niel R. Muller January 21, 1987 Page 2 gaseous storage of hydrogen and oxygen on-site at Peach Bottom, as required to supply gaseous hydrogen and oxygen to the station for the implementation of Hydrogen Water Chemistry. The safety evaluation concludes that the storage of large quantities of hydrogen and oxygen on-site at Peach Bottom for use in Hydrogen Water Chemistry does not involve safety related equipment, that the operation of the storage systems, including liquid hydrogen and oxygen storage and vaporization and hydrogen gas storage, will not affect safety related equipment, and that the location and storage of large quantities of liquid hydrogen and oxygen on-site at Peach Bottom does not constitute an unreviewed safety question. Attachment 1 contains the aforementioned Philadelphia Electric Company safety evaluation, as well as the safety analyses for the Liquid Hydrogen and Oxygen Storage Systems prepared by Stearns Catalytic Corporation, and the guidelines for Permanent BWR Hydrogen Water Chemistry Installation (March 1986) prepared by Electric Power Research Institute.

Philadelphia Electric Company is planning to implement Hydrogen Water Chemistry on Unit 2 shortly after the conclusion of the Unit 2 1987 refueling outage (May 1987), and on Unit 3 shortly after the conclusion of the Unit 3 1987/88 refueling and pipe replacement outage.

In the Reference (1) latter, Philadelphia Electric Company indicated that details of the liquid hydrogen and oxygen storage system design would be submitted to the NRC for review and approval. Subsequently, our safety evaluation has determined that an unreviewed safety question is not involved. Therefore, prior NRC review and approval is not required in accordance wi'th the provisions of 10 CFR 50.59(a)(2). However, because of the concerns raised in the Reference (2) letter, Philadelphia Electric Company is providing the attached report to the NRC for information.

Should you have any questions or require additional information, please do not hesitate to contact us.

Very truly yours, Attachment cc: Dr. T. E. Murley, Administrator, Region I, USNRC T. P. Johnson, Resident Site Inspector