ML20010H425
| ML20010H425 | |
| Person / Time | |
|---|---|
| Site: | Allens Creek File:Houston Lighting and Power Company icon.png |
| Issue date: | 09/18/1981 |
| From: | Hodges M Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20010H414 | List: |
| References | |
| NUDOCS 8109240448 | |
| Download: ML20010H425 (6) | |
Text
O UNITED STATES OF AMERICA 14UCLEAR REGULATORY COMMISS10tl BEFORE THE ATOMIC SAFETY AND LICENSIl4G BOARD In the Matter of HOUSTON LIGHTING AND POWER COMPANY )
Docket No. 50-466
)
(Allens Creek fluclear Generating
)
Station, Unit 1)
)
HRC STAFF TESTIMONY OF MARVIN W. (WAYl4E) H0DGES ON DOHERTY CONTEllTION 388 Q.
Please state your name and position with the NRC.
A.
Ny name is Marvin W. (Wayne) Hodges.
I an employed by the U.S.
Nuclear Regulatory Commission as a section Leader, Section B, in the Reactor Systems Branch of the Division of Systems Integration. A copy of uy professional qualifications has previously been submitted, y.
What is the purpose of your testimony?
A.
The purpose of this testimony is to respond to Duherty l
Contention 38B which states:
Contrary to NUREG-0578, the reactor cannot be brought to cold shutdown in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
l Q.
What is meant by " cold shutdown"?
A.
" Cold shutdown" means that the average reactor coolant tempera-ture is less than 212 F and the reactor mode switch is in the shutdown l
position with the reactor subcriticcl.
l Q.
Does the HP.C require that the reactor be brought to cold shut-down in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />?
g924044881093g-7 ADOCK 05000466 PDR
D o A.
No. Branch technical position RSB 5-1, given in the Standard Review Plan (HUREG-75/067) states that the RHR system (s) shall be capa-ble of bringing the reactor to a cold shutdown condition, with only off-site or onsite power available, within a reasonable period of time follow-ing shutdown, assuming the most limiting single failure. A reasanable time has generally been interpreted to be about 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> has been based on the availability of high quality water to the steam generators of PWRs. Times longer than 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />) have been accepted by the Staff.
Q.
Can ACNGS be brought to cold shutdown in less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />?
A.
Yes. Based on information provided in the ACNGS PSAR, my calcu-lations show that the ACNGS can be brought to cold shutdown in less than 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.
For these calculations, I used the curve fcr heat removal Cdpability of the RHR heat exchanger given in section 5 of the ACHGS PSAR and I conservatively assumed that the decay heat remained constant at 38.3 Mw, which is the decay heat after being shutdown for two hours.
The initial phase of the cooldown, which consists of dumping steam to the condenser, is limited by technical specifications to 100 F/hr.
Therefore, it takes at least two hours to reach the pressure (125 p;ia) at which the RHR system is normally used for shutdown cooling. At 125 psia, the saturation temperature is approximately 344 F while the initial operating temperature was 544 F.
Even with allowing time to flusn the RHR system, qy calculations show that cold shutdown can be achieved in less than 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.
Q.
Wnat is your conclusion regarding Mr. Doherty's allegation?
. +'
A.
The contention appears to be based upon a misunderstanding of regulatory requirements.- While the Allens Creek reactor will not be required to reach cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> under the postulated cos.ditions in the Standard Review Plan, ry calculations demonstrate that cold shutdown can be achieved in substantially less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Thus, there is no basis for the concern expressed by Mr. Doherty.
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UNITED STATES OF AMERICA 14UCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSIfiG BOARD In the Matter of
)
)
HOUSTON LIGHTING AND POWER COMPANY )
Docket No. 50-466
)
(Allens Creek fluclear Generating
)
-Station, Unit 1)
)
11RC STAFF TESTIM 0liY OF MARVIN W. (WAYl4E) H0DGES Old DOHERTY CONTENTION 38B Q.
Please state your name and position with the NRC.
A.
My name is Marvin W. (Wayne) Hodges.
I an employed by the U.S.
Nuclear Regulatory Dwaission as a Section Leader, Section B, in the Reactor Systems Branch of the Division of Systems Integration.
A copy of 1,1y professional qualifications bas previously been submitted.
Q.
What is the purpose of your testimony?
A.
The purpose of this testimony is to respond to Doherty Contention 388 which states:
Contrary to NUREG-0578, the reactor cannot be brought to cold shutdown in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Q.
What is meant by " cold shutdown"?
- r..
" Cold shutdown" means that the average reactor coolant tempera-l ture is less than 212 F and the reactor mode switch is in the shutdown l
l position with the reactor subcritical.
l l
Q.
Does the i4RC require that the reactor be brought to cold shut-down in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />?
l u
A.
No.
Branch technical position RSB 5-1, given in the Standard ReviewPlanf(HUREG-75/087)statesthattheRHRsystem(s)shallbecapa-ble of bringing the reactor to a cold shutdown condition, with only off-site or onsite power available, within a reasonable period of til.e follow-ing shutdown, assuming the most limiting single failure. A reasonable time has generally been interpreted to be about 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
The 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> has been based on the availability of high quality water to the steam generators of PWRs.
Times longer than 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />) have been accepted by the Staff.
y.
Can ACNGS be brought to cold shutdown in less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />?
A.
Yes.
Based on information provided in the ACNGS PSAR, ny calcu-lations show that the ACNGS can be brought to cold shutdown in less than 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.
For these calculations, I used the curve for heat removal Cdpability of the RHR heat exchanger given in section 5 of the ACHGS PSAR and I conservatively assumed that the decay heat remained constant at 38.3 t1w, which is the decay heat after being shutaan for two hours.
The initial phase of the cooldown, which consists of dumping steam
'r. f to the condenser, is limited by technical specifications to 100 F/4A.
Therefore, it takes at leht two hours to reach the pressure (125 psia) at which the RHR system is normally used for shutdown cooling. At 125 psia, i
the saturation temperature is approximately 344 F while the initial operating temperature was 544 F.
Even with allowing time to flush the RHR system, ry calculations show that cold shutdown can be achieved in less than 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.
Q.
What is your conclusion regarding Mr. Doherty's allegation?
a,
A.
The contention appears to be based upon a saisunderstanding of regulatory requirenents.
While the Allens Creek reactor will not be required to reach cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> under the postulated conditions in the Standard Review Plan, my calculations demonstrate that cold.. shutdown can be achieved in substantially less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Thus, there is no basis for the concern expressed by Mr. Doherty.
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