ML20080M881
| ML20080M881 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 09/28/1983 |
| From: | Kemper J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8310040296 | |
| Download: ML20080M881 (6) | |
Text
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PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 1881 -1981 PHILADELPHIA. PA.19101 (215) 841-4 5o 2 JOHN S. KEMPER September 28, 1983 vico, csiocar ENGeME E RtNG AND RESS ARCM Mr. A. Schwencer, Chief Licensing Branch No. 2 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C. 20555
Subject:
Limerick Generating Station, Units 1 and 2 Core Performance Branch
Reference:
PECO and NRC Conference Call Dated June 24, 1983 File:
GOVT (NRC)
Dear Mr. Schwencer:
As requested by the Core Performance Branch Reviewer in the referenced telecon, we are providing additional information on Thermal Hydraulic Stability with this letter.
The first attachment, entitled Requested Additic,nal Information, provides a response which indicates that the Limerick Thermal Hydraulic Stability Analysis was re-evaluated using a bounding value for fuel gap 2
conductance of 1000 BTU /HR-f t _oF for the Limerick core and found to be acceptable.
The second and third attachments are a draft revision to FSAR table 4.4-13 and a draft revision to FSAR figure 4.4-7.
These revisions are being made to document the re-evaluation discussed above.
The attached draf t FSAR revisions will be incorporated into the FSAR exactly as they appear on the attachments in the revision scheduled for October,1983.
Sincerely, RJS/gra/E-14 Copy to:
See Attached Service List D
G310040296 830928 l
PDR ADOCK 05000352 l
l A
PDR I
1 l
cc: Judge Lawrence Brenner (w/ enclosure)
Judge' Richard F. Cole (w/ enclosure)
Judge Peter A. Morris (w/ enclosure)
Troy B. Conner,.Jr., Esq.
(w/ enclosure)
Ann P. Hodgdon, Esq.
(w/ enclosure)
Mr.-Frank R. Romano (w/ enclosure)
~Mr. Robert L. Anthony (w/ enclosure) 1 Mr. Marvin I. Lewis (w/ enclosure)
' Judith A. Dorsey, Esq.
(w/ enclosure)
Charles W. Elliott, Esq.
(w/ enclosure)
Jacqueline I. Ruttenberg (w/ enclosure)
Thomas Y. Au, Esq.
(w/ enclosure)
Mr. Thomas Gerusky (w/ enclosure)
Director, Pennsylvania Emergency Management Agency (w/ enclosure)
Mr. Steven P. Hershey (w/ enclosure)
Angus Love, Esq.
(w/ enclosure)
Mr. Joseph H. White, III (w/ enclosure)
David Wersan, Esq.
(w/ enclosure)
Robert J. Sugarman, Esq.
(w/ enclosure)
Martha W. Bush, Esq.
(w/ enclosure)
Spence W. Perry, Esq.
(w/ enclosure)
Atomic Safety and Licensing Appeal Board (w/ enclosure)
Atomic Safety and Licensing Board Panel (w/ enclosure)
Docket and Service Section (w/ enclosure) l
. ~.
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' REQUESTED ADDITIONAL INFORMATEDN! I" '
CORE PERFORMANCE BRANCH
SUBJECT:
FSAR Subsection 4.4.4, Thermal-Hydraulic Stability l
REFERENCE:
Telecon, S. Sun (NRC) to R. J. Stipcevich (PECo)
"LCS T-H Stability Analysis", June 24, 1983 CONCERN:
In reference telecon the NRC reviewer stated his concern that the Limerick Thermal-Hydraulic Stability Analysis,
. as documented in the FSAR, included an input value for
~
fuel gap conductance that was lower than some of those recently submitted by other similar BWR/4's. Since thermal-hydraulic stability decreases monotonically with increasing fuel gap conductance, he questioned the validity of the conclusions that were drawn from that analysis.
. RESPONSE:
The analytical results, i.e., decay ratio, as documented in the LGS FSAR Section 4.4 were dgrived from a calculated gap conductance of 533.5 BTU /hr-ft
'F for the previously designed-8x8 fuel with one water rod. The results show that sufficient margin exists in the Limerick core design.
For the current P8x8R fuel design (prepressurized retrofit with two water rods) -the galculated gap conductance increased to 628 BTU /hr-ft
- F.' gA reevaluation using a bounding value of.1000 BTU /hr-f t
- F has been performed
~ for.the Limerick core. The resulting decay ratio still remains below 1.0.
This analysis is documented in the attached FSAR update-to Table 4.4-13 and Figure 4.4-7.
- Figures 4.4-8 through 4.4-10 are left unchanged since
- use of the bounding fuel gap' conductance does not alter them significantly.
This bo'unding vglue of fuel gap conductance (1000 BTU /hr-ft
- F) was used only in the above evaluation, for the sole purpose of demonstrating the inherent design i
margin of the Limerick core with respect to thermal hydraulic stability.
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LIMERICF GENERATING STATION UNITS 1 AND 2 FINAL SAFETY ANALYSIS REPORT TOTAL CORE STABILITY FIGURE 4.4-7
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