ML20196E715
| ML20196E715 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 06/21/1988 |
| From: | Schnell D UNION ELECTRIC CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| ULNRC-1796, NUDOCS 8807010677 | |
| Download: ML20196E715 (5) | |
Text
_ _ _ _ _ _ _ - _ _ _ _
s Union Etscraic a
1901 Gratiot Street. St. Louis Donald F. Schnell Vce President June 21, 1988
.U.S.
Nuclear Regulatory Commission Attn:
Document Control Desk Washington, DC 20555 Gentlemen:
ULNRC-1796 Docket Number 50-483 Callaway Plant Response to Question on Wide Range Gas Monitor Concentration Display Variance Request Reference 1)
ULNRC-1393 dated October 24, 1986 2)
NRC letter dated May 10, 1988 from T.W. Alexion to D.F. Schnell Reference 1 transmitted our variance request concerning the wide range gas monitor concentration display.
Attached to this letter is our response to your request for additional information on this subject transmitted by Reference 2.
If there are any further questions, please contact us.
Very truly yours, Donald F.
Schnell DFS/blo Attachment Cf I I i
8807010677 880621 PDR ADOCK 05000483 P
DCD Mashng Address: P.O. Box 149, St. Louis, MO 63166
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STATE OF MISSOURI )-
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'S S CITY OF.ST. LOUIS )
Donald F.
Schnell, of lawful age,~being first duly sworn upon oath'says that he is Vice' President-Nuclear.and an officer.of Union Electric Company; that he.has read the foregoing. document and knows the content'thereof; that he has executed the same for and on behalf of said company with full power and authority. to do so; and that the facts therein stated are true and correct to the best of his knowledge, in formation and belief.
By r/A Donald F'.
Schnell Vice President Nuclear SUBSCRIBED and sworn to before me this d/d day of 1987 AA BARBARA E PFAFF ~
ISSOURI l
NOTARY PUBUC, STATE Of 22, 1989.
MY 00WISS10N EXPIRES APRIL ST. LOUIS COUNTY l
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w Attachment to ULNRC-1796 Question:
The licensee.has not provided enough information to justify this proposed deviation.
Provide a descrip-tion of procedures or calculational methods to be used for_ converting instrument readings to release rates per unit. time, based on exhaust air flow and considering radionuclide spectrum distribution as a function of time after shutdown.
The system can meet the intent of the requirement if the system, including the correction factor curves, provides estimates of releases according tx) (above) clarifica-tion in (4) (b) of Item II.F.1, Attachment 1, on page II.F.1-3 of NUREG-0737.
Response
The Callaway Plant unit vent monitor is a General Atomics Wide Range Gas Monitor (WRGM) which employs a stack velocity system to furnish a signal to the WRGM proportional to the unit vent flow rate.
The WRGM RM-80 uses this signal to maintain isokinetic flow ~ control and for calculating effluent release rate (pCi/sec).
If the stack velocity system is out of service, the release rate can be manually calculated from the WRGM output in pCi/cc and the unit vent flow rate determined by the number of fans operating per Emergency Plan Implementing Procedure No. EIP-ZZ-01211 as follows:
(Monitor reading- ( pCi/cc)) X (unit vent flow rate (CFM)) X (472 cc/sec/CFM) = release rate (pCi/sec).
The release rate, either manually calculated or dis-played by the WRGM, will be manually corrected for radionuclide spectrum changes by multiplying the release rate by the spectrum correction factor for the time period since reactor shutdown.
The spectrum correctiou factors are based on the difference between the expected detector response to noble gas spectrum distribution changes as a function of time after reactor shutdown as deter-mined by the computer code "ORIGIN 2",
and the WRGM conversion factors.
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ULMRC-1796-cc:
Gerald Charnoff, Esq.
Shaw, Pittman, Potts & Trowbridge 2300 N.
- Street, N.W.
Washington, D.C.
20037 Dr. J. O. Cermak CFA, Inc.
4 Profession 61 Drive (Suite 110)
Gaithersburg, MD 20879 R. C. Knop Chief, Reactor Project Branch 1
.U.S.
Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 Bruce Little Callaway Resident Office U.S.
Nuclear Regulatory Commission
.RRil Steedman, Missouri 65077 Tbm Alexion ' (2)
Office of Nuclear Reactor Regulation U.S.
Nuclear - Regulatory Commission Mail Stop~316 7920 Norfolk Avenue Bethesda, MD 20014 Manager, Electric Department Missouri-Public Service Commission P.O.
Box 360 Jefferson City, MO 6S102 U.S.
Nuclear Regulatory Commission
-ATTN:
Document Control Desk Washington, D.C.
20S55
,s ULNRC-1796 bcc:
D. Shafer/A160.761
/QA Record (CA-758)
Nuclear Date
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DFS/ Chrono.
D.
F. Schnell-
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E. Birk A.
P. Neuhalfen M.. A.
Stiller G.
L '. Randolph R.
J.
Irwin H.-Wuertenbaecher W.
R. Campbell A.
C.
Passwater R.
P. Wendling D.
E.
Shafer D.
J. Walker O.
Maynard (WCNOC)
N. P. Goel~(Bechtel)
GS6.37 (C A-4 60)
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P. Sharkey NSRB (Sandra Auston)
N. - G. Slaten B.
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Holderness E160.104 1