ML19263C952
| ML19263C952 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 02/28/1979 |
| From: | Ziemann D Office of Nuclear Reactor Regulation |
| To: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| References | |
| TASK-05-10.A, TASK-5-10.A, TASK-RR NUDOCS 7903200104 | |
| Download: ML19263C952 (8) | |
Text
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- b UNITED STATES y*
- g NUCLEAR REGULATORY COMMISSION 5
j WASHINGTON, D. C. 20555 e
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February 28, 1979 Docket No. 50-213 Mr. W. G. Counsil, Vice President Nuclear Engineering and Operations Connecticut Yankee Atomic Power Company Post Office Box 270 Hartford, Connecticut 06101
Dear Mr. Counsil:
Enclosed is a copy of ot:r draft evaluation of Systematic Evaluation Program Topic V-10.A.
You are requested to examine the facts upon which the staff has based its evaluation and respond either by confirming that the facts are correct, or by identifying any errors.
If in error, please supply corrected infonnation for the docket.
We encourage you to supply for the docket any other material related to these topics that might affect the staff's evaluation.
Your response within 30 days of the date you receive this letter is requested.
If no response is received within that time, we will assume that you have no comments or corrections.
Sincerely, Od2 g
Dennis L. Ziemanr.,
hief Operating Reactors Branch #2 Division of Operating Reactors
Enclosure:
Topic V-10.A cc w/ enclosures:
See next page 7903200\\vf
SYSTEMATIC EVALUATION PROGRAM PLANT SYSTEMS / MATERIALS HADDAM NECK Topic V-10.A Residual Heat Removal System Heat Exchanger Tube Failures The safety objective of this review is to as_sure that impurities from the cooling water system are not introduced into the primary coolant '
in the event of residual heat removal system heat exchanger tube failure. This was expanded to assure that adequate monitoring exists -
to assure no leakage of radioactive material in the other direction -
into the service water and thus to the environment.
Information for this assessment was gathered from. plant personnel during the safe shutdown review site visit in July 1978 and from related tele-phone conversations.
Information was also taken from the Haddam Neck Technical Specifications and the Haddam Neck Final Safety Analysis Report.
The bases for the review of these cooling systems on todiy's plants include:
(1) the NRC's Standard Review Plan (SRP) 9.2.1, which requires that the ~ service water system include the capability for detection and control of radioactive leakage into and out of the system and prevention of accidental releases to the environment; (2) SRP 9.2.2, which requires that auxiliary cooling water systems (such as the residual h ;t removal system) include provisions for detection, collection and control of system leakage and means to. detect leakage of activity from one system to another
'and preclude its release to the environment; and (3) SRP 5.2.3, which discusses compatibility cf materials with reactor coolant and requires monitoring and sampling of the primary coolant system. These Standard Review Plans were used only in the compari. son of Haddam Neck acainst
Mr. W. G. Counsil February 28, 1979 CC Day, Berry.a Howard Counselors at Law One Constitution Plaza Hartford, Connecticut 06103 Superintendent Haddam Neck Plant RFD #1 Post Office Box 127E East Hampton, Connecticut 06424 Mr. James R. Himmelwright Northeast Utilities Service Company P. O. Box 270 Hartford, Connecticut 06101 Russell Library 119 Broad Street Middletown, Connecticut 06457 K M C Inc.
ATTN: Mr. Jack McEwen 1747 Pennsylvania Avenue, N. W.
Suite 1050 Washinoton, D. C.
20006 9
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today's criteria and were not used as licensing requirements which must be met, especially if the plant incorporates other equally acceptable means of accomplishing the stated goals.
Unlike the state sent of the problem in the topic definition, Haddam Neck's residual heat removal (RHR) system would normally be at a higher pressure than the closed cooling water (CCW) system which cools it.
The CCW system operates at a higher pressure than the service water System, which cools the CCW heat exchanger and foms the ultimate heat sink.
It is noted here only for information that service water would be used directly to cool the two RHR heat exchangers during post-Loss of Coolant Accident (LOCA) conditions. This presents no concern to us for the purpose of this review, since cleanup from the highly unlikely LOCA for possible return to service, would include flushing of the primary system
.and detailed systems inspection.
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-Adcording to plant sources, the lowest pressure on the primary side of the two RHR heat exchangers is approximately 100 psig when the primary system is depressurized and the reactor head removed.
Even when the RHR system is being shut down after use (and thus during startup), pressure at the heat exchangers remains above that of the CCW system, which operates at pressures between 83 and 85~ psig at these heat exchangers. Thus it is readily seen that if tube leakage were to occur, its direction would be from the primary coolant system to the CCW system.
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Even though this is the case, present NRC guidance (SRP 5.2.3) requires monitoring and sampling of the primary coolant system. This is especially.
important since the Haddem Neck licensee has requested that the applicable Technical Specification be amended to allow short-tem RHR system shutdowns during certain refueling outage evolutions, to decrease turbulent flow around.
the fuel assemblies. During these pericds, leakage from CCW to the RHR system could occur. Haddam Neck procedures do presently require sampling of the
primary system three times per day when the RHR system is in operation.
This sampling program checks for boron concentration, pH, conductivity, chlorides, and includes a gama analysis for coolant activity. There is also a semi-annual RHR inservict inspection chemical analysis program and a sampling program for RHR system leakage.
However, the Haddam Neck Technical Specifications do not presently contain any chemistry limits or surveillance requirements for primary coolant chemistry. Such requirements will be added es a result of the present staff and licensee effort to write and implement the Standard Technical Specifications for the Haddam Neck facility.
We anticipate that implementation of the new specifications will occur prior to the end of the Systematic Evaluation Program, Phase II, and we consider the sa=pling required by plant procedures to be adequate in the interim.
-As a means of detecting leakage into (from the RHR system or other cooled components) or out of [to the RHR system (highly unlikely) or to the service water system] the CCW system, the CCW system surge tank incer-porates high and low level alarms which annunciate in the plant's min centrol room [ Final Safety Analysis Report, Section 5.2.3.2].
- Also, leakage of radioactive material from the RHR system heat exchangers (or any other CCW-cooled cc.penent) would be monitored and alarmed by the CCW system'= continuous, radiation monitor which is on the CCW pumps' suction piping.
CCW system sampling is performed once per week in accordance with Slant procedures. The sampling program includes pH,
- conductivity. chrer. ate (a compound of which is used for corrosien inhibition), ga=a scanning, and a tritium analysis.
As noted above, the CCW heat exchangers (two) are cooled by the service water system. According to plant sources, CCW pressure at these he'at
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exchangers is between 83 ar.d 85 psig, with service water operating between SS and 70 psig.
Tnus any tube leakage would result in CCW
leakage to the environment. Also, although it would take highly unlikely undetected simultaneous leakage from the RHR heat exchanger (s) (or any other CCW-cooled component) and the CCW heat exchanger (s) in order for radioactive material to escape to the environment, prudent design, as dictated by SRP 9.2.1, would_ require the installation of a radiation detector and alarm on the service water system. Haddam Neck's service water system does incorporate such a detector and alarm, as noted in Appendix B Technical Specification Table 2.4-3, with calibration require-nents stated in Appendix B Technical Specification 2.4.2.6.
Therefore, with the exception noted above, we have found that the Haddam Neck plant m~ ets today's criteria. With regard to the question of e
Technical Specifications, no action on the part of the licensee is required at this time.
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