ML19323C499
| ML19323C499 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 04/22/1980 |
| From: | Baer R Office of Nuclear Reactor Regulation |
| To: | Stampley N MISSISSIPPI POWER & LIGHT CO. |
| References | |
| NUDOCS 8005160018 | |
| Download: ML19323C499 (7) | |
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APR 2 2 M Decket Nos. 50-416 and E0-417 l
Mr.
- !. L. Stampley, Vice President Production and Engineering Mississippi Power and Light Company P. O. Box 1640 Jackson, Mississippi 39205
Dear Mr. Stampley:
SUBJECT:
REQUESTS FOR ADDITIONAL 1NF0PMATION (Grand Gulf Nuclear Station, Units 1 and 2)
As a result of our review of the information contained in the Final Safety Analysis Report for the Grand Gulf Nuclear Station, Units 1 and 2, we have developed the enclosed requests for additional information.
Included are questions from the Instrumentation and Control Branch concerning Sections 7.6 and 7.7.
We request that you amend your Final Safety Analysis Report to reflect your responses to the enclosed requests as soon as possible, and to inform the Licensins droject Manager, Thomas C. Houghton, of the date by which you intend to respond.
Please contact us if you desire any discussion or clarification of the enclosed requests.
Sincerely,
, / p [E 't k
/ cc '- 1 Ro'bert L. Baer, Chief Light Water Reactors Branch No. 2 Division of Project Management
Enclosure:
Requests for Additional Information ecs w/ enclosure:
See next page THIS DOCUMENT CONTAINS P00R QUAUTY PAGES
Mr. N. L. Stampley APR 2 2 QNN)
Mr. N. L. Stampley Vice President - Production Mississippi Power and Light Company P. O. Box 1640 Jackson, Mississippi 39205 ces: Mr. Robert B. McGehee, Attorney Wise, Carter, Child, Steen and Caraway P. O. Box 651 Jackson, Mississippi 39205 Troy B. Conner, Jr., Esq.
Conner, Moore and Corber 1747 Pennsylvania Avenue, N. W.
Washington, D. C.
20006 Mr. Adrian Zaccaria, Project Engineer Grand Gulf Nuclear Station Bechtel Power Corporation Gaithersburg, Maryland 20760 l
l
APR 2 a IS80
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GRAND GULF FSAR SECTIONS 7.6 AND 7.7 QUESTIONS Qo31.7s The discussion of the refueling interlocks in Section 7.6.1.1 is (7.6.1.1) incomplete as follows:
(7.7.1. 2)
- 1) Section 7.6.1.1.2 indicates that the interlock is fail-safe for the mcvement of control rods but does not address the effect on the refueling platform operation.
- 2) Section 7.6.1.132 states that the innit of a single rod being withdrawn is implemented by disallcwing the selection of a different rod once the "all rods in"
' signal disappears.
It is not clear how the ganged rod withdrawal described in Secticn 7 7.1.2 is circu= vented by this interlock.
- 3) Section 7.6.1.136 states that " Separation is provided, to a degree, fer two of the three interlocks." Tne two interlocks involving the control rod operatien are identified as having two separcte channels, implying that the interlocks for the refueling platform are single channel.
4)
Even though refueling crerations are the means by which the core reactivity is restored, no mention is made of any interlocks that ensure that the core reactivity is adequately monitored during refueling (nce is there reference to the mechanisms used to ensare refueling with suitable fuel).
Sevise the FSAR to mere clearly identify the degree to which the interlocks are single failure pro)f.
Justify the exclusien of flux menitoring instrts.ents frcc the interlocks en the c;eratien i
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APR 2 2 Ig of the refueling platform anc indicate h:w ecmpliance with GCCs 10, 16, and 27 are n.aintained and/cr re-established following refueling.
QO31.79 Sections 7.6.1 3 3 1 and 7.6.1 3 3 4 state that the recirculation (7.6.1 3) suction valves have " independent and diverse interlocks" to (Crawings prevent the valves from opening when system pressure is high.
E 12-1050 Identify the diverse method of signalling high system pressure.
E21-1090)
The elementary dicgrams only show high area temperature, low reactor water level and high reacter pressure as interlocks on the valves. The diagrams shaw that the recirculation discharge valve is operated from the sar.e logic as the suction valve.
In addition, the order in which the statements in Section 7.6.13.3.1 are made makes it unclear as to whether the last sentence of the first paragraph applies to all the valves er only to the recirculation suction valves.
Revise the FSAR cs necessary to clarify these two paints.
QO31.80 EeVisE the analysis for cCmpliance with GDC 29 to address the (7.6.2.4) concern of GDC 29 that the system will perform with reliability
~
for anticipated operational occurrences.
An instrument that only fbnetiened one time out of ten could still meet your interpretaticn.
QO31.81 The presentations in Sections 7.6.1.5 3 1.2 and 7.6.2.5.1
( 7. 6.1. 5 )
provide a questionable explanatien of hcw the SEFs res:end to (7.6.2.5) reactivity changes. This in turn makes the cr. clysis for l
(
1
i APR 2 2 %
compliance to design requireaents cuesticnable.
Fevise FSAR to address the following specific paints.
- 1) Justify the claim that the SKFs are designed to.T,cet the single failure criterion in light of your statement that the SEM channels are not redundant.
- 2) Provide documentation to support the contention that cne "section" of the core can independently be en a 2C-second period (Section 7 6.2.5.1).
3)
Indicate whether the redundancy / single failure
~
relationship of the SRMs is applicable to the IRMs.
QO31.82 Revise Figure 7.6-10, or provide an additional figure, to show (7.6.2.5) the APEM response to full withdrawal of a control rod at rated
( F7. 6-14) power stated in Section 7. 6. 2. 5. 4.1.
QoII. 83 The rod block monitor and the rod pattern control system are the
( 7. 6.1. 6) parts of the rod control and informatica system that are (7.6.1.7) identified as falling into the "all other systems required fbr (7.6.2.6) safety" category.
Eoth Sections 7.6.1.6 and 7.6.1.7 state that (7.6,2.7) the red block monitor is the mechanism by which the restrictions s
(T7.1-3) en rod motion, generated by the rod pattern control system, are implemented.
- mend your FSAR to address all the safety criteria in Table 7.1-3 that are identified as applicable to ECIS.
The criteria should be addrassed far both the REM and EPCS.
APR 2 % 120 0031.84 The equi; cent design secticn of the recirculation pt. p trip (7. 6.1. 8) contains a number of e'erors as follot s:
(7.6.2.8) 1)
It refers to Fic a 7.2-7 for initiating circuits and to
. nt while cach figure actually (T7.6-8)
Figure 7.2.-3 for Auf s./
s..
(Crawing sbws initiation and Icgic for one type of valve (Ficurc 7.2-3 C71-1050) is for control valves and Figure 7.2.7 is for stop valves).
- 2) Re low p:wcr autanatic bypass of the trip shown on Crawing C71-1050 is not discussed in the design basis nor addressed in the analysis (IEEE 279, para 6raph 4.12).
- 3) Sections 7.6.1.8 3 2 and 7.6.1.E.5 are affected by the bypass in 2) above.
- 4) Figure 7.2-1 does not show the normal condition of sensors and Icgic centrary to statcment in Section
- 7. 6.1. 8. 5.1.
- 5) Tne RFI ( ATAS) shown on Crawing 5?I-1C30 is not discussed in this or any other part of Section 7.
- 6) ne grevicusly noted (031.56) cisparity between the FSAR and sy;'em drawigs applies to Section 7.6.1.8.6 b.
end Tl.6-8.
Revise the FSAR and/or the drawir.gs to prcvide an accurate ar.d complete description and analysis of the RPT system.
QO31.85 The analysis for requirement 4.20 of IEEE 279 for the Ccmponent
( 7. 6. 2.10)
(7.5)
Cooling Water (CCW) merely refers to Section 7.5.
Since Section 7.5 does not identify any CCW readouts as being part of the STSI, amend the appropriate section to resolve the discrepancy.
c.
t APR 2 0 N Cite the reference that establishes that diversity is unequivc-QO31.86 (7.6.1.11) cally not required for systems that are in constant operation.
Also, describe the protective action taken by the operator to
" prevent the addition of stear to high-temperature pool water."
QO31.87 The interpretation of diver Sity in Section 7.6.1.12.6 is (7. 6.1.12) unacceptable; amend your FSAR to delete any reference to manual initiatiqn as a diverse protective action, t
go31.as Sections u.6 and 7.4 state that the stancby liquid control system (7.7.1 3) is the second reactiv tty centrol system required by ccc 26.
(7.7.2 3)
Section 3.1 states that the recirculation flow control system (rcs) is (7.4.1 3) the seccnd reactivity centrol system required by ctc 26, and (7.4.2.2)
Sectica 7 7 implies that the.VCS is the second system through (4.6) the statcments made (in 7.7.2 3) in the analysis for (3.1) ccmpliance with IEEE 279 and GCC 26.
Revise your FSAR to indicate how you ccmply with CDC 26.
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