ML19309C392
| ML19309C392 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom, Limerick  |
| Issue date: | 03/31/1980 |
| From: | Boyer V PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8004080543 | |
| Download: ML19309C392 (2) | |
Text
a PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET PHILADELPHI A. PA.19101 1215)641 4500 f.brch 31,1980 S r. = ~...,
Nuclear Power Mr. Harold R. Denton Office of Nuclear Reactor Regulation Nuclear Regulatory Commission Washington, DC 20555
Subject:
Imolementation of ATWS Mitigation Alternative 3A
Dear Mr. Denton:
The Philadelphia Electric Company has reviewed the four volumes of NUREG-0460 and the General Electric Company document NEDE-24222, dated December,1979, has participated in discussions with the General Electric Company, and has heard recent NRC staff and General Electric Company cresentations to an ACRS Subcommittee. We believe an anticipated transient vithout scram (ATWS) is a small contributor to overall risk to the public, and that prevention of this event rather than mitigation of this event is preferable.
However, if we subscribe to the staff's position that ATWS is not an extremely re. note event, then we come to the conclusion that Alternate 3A, as described in volume 4 (draf t) of NUREG-0460 is the proper solution to the ATWS concern.
Given the situation that both the staff and the Advisory Committee on Reactor Safeguards' Subcommittee on ATWS believe that ATWS is not an extremely re-mote event, the Philadelphia Electric Company commits to installing Alternate 3A in Units 2 and 3 of our Peach Bottom Atomic Power Station and in Units 1 and 2 of our Limerick Generating Station.
Wa interpret Alternate 3A to require the alternate rod injection system (ARI), recirculation pump trip (RPT), changes in logic to reduce the vessel isolation events and to permit feedwater runback, automation of an 86 gallon per minute standly liquid control system, modification of the SCRAM discharge volume by adding additional level switches, and assurance that containment isolation valves close quickly if fuel failure should occur. The RPT feature has been installed in Units 2 and 3 of our Peach Bottom Atomic Power Station, and we previously committed to install ARI and RPT e our Limerick Generating Sta tion.
Y t/O 8004080643
e Mr. H. R. Denton 2
March 31,1980 The modifications necessary to be accomplished at our Peach Bottom units will be designed over the ensuing months, with completion of our design by December,1980 as our goal. The equipment will then be ordered, and the installation of the quipment shall be accomplished with respect to equipment availability. The modifications necessary at Limerick Generating Station will be accomplished prior to unit startup.
Sincerely,
.A l',,useaf.O*',,h Copy to Prof. William Kerr, ACRS i