ML20137Q914
| ML20137Q914 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 01/30/1986 |
| From: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Muller D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8602070105 | |
| Download: ML20137Q914 (7) | |
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l PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O. BOX 8699 j.
PHILADELPHI A. PA.19101 i
SHIELDS L. D ALTROFF ELECT sc Pao CT om j
January 30, 1986 I
Docket Nos. 50-277 50-278 a
i-3 Mr. Daniel R. Muller, Director I
BWR Project Directorate #2 Division of Boiling Water Reactor Licensing U.S. Nuclear Regulatory Commission Washington, D.C.
20555 i
SUBJECT:
Peach Bottom Atomic Power Station Units 2 and 3 - Installation of New Spent Fuel Storage Racks a
j
Dear Mr. Muller:
l During recent telephone conferences, several questions and requests for additional spent fuel pool evaluations have been made by the NRC Staf f.
In response to those requests, the 4
following attachments are provided:
i o ATTACHMENT A'- Provides responses to questions one and i
two in regards to interpreting the Safety Analysis Report submitted August 1, 1985.
l' o
ATTACHMENT B - Provides an evaluation of the off-site i
dose rate consequences of allowing the spent fuel pool to boil at 212 degrees Fahrenheit.
The off-site dose evaluation of a boiling spent fuel pool was first completed for.the Limerick Generating Station.
Because of the design similarities between the Peach Bottom
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Atomic Power Station and the Limerick Generating Station i
facilities and systems, an evaluation was completed based on the previous analysis performed for the Limerick Station.
The i
differences between the Peach Bottom spent fuel pool and the i
Limerick pool were incorporated into the evaluation assumptions.
The evaluation is provided in Attachment B.
kt 8602070105 860130 PDR ADOCK 05000277
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Mr. Daniel R. Muller January 30, 1986 Page 2 Should you have any further questions or need additional information, please do not hesitate to contact us.
Very truly yours, ll c ( ' f_ t.
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Attachments cc:
Dr. T. E. Murley, Administrator, Region 1, NRC w/o attachments T.
P. Johnson, Resident Site Inspector w/o attachments
January 30, 1986 Docket Nos. 50-277 50-278 ATTACHMENT A
-Responses to Request for Additional Information - January 30, 1986 Peach Bottom Atomic Power Station Units 2 And 3 Installation of New Spent Fuel Racks ATTACHMENT A o
Page 1 of 2,' Response to Question #1 o
Page 2 of 2, Response to Question #2.
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January 30, 1986 Docket Nos. 50-277 50-278 ATTACHMENT A Page 1 of 2 Question #1 Page 3-20, Rev.
1, indicates normal refueling; (3)(c) "with one exchanger in service - time to reach 150 degrees P = 7.3 days *," and full core of fload (4)(c) " time to reach 150 degrees F one exchanger in se rvice = 7. 3 days *".
- However, the heat load for the first case is shown as 13.14 X 10P6 BTU /HR and the heat load is shown as 23.12 X ICP6 BTU /HR for the second case.
Are both correct?
Response to Question #1 The heat loads for both cases are correct.
The loads of 13.14 X 10P6 BTU /HR for normal refueling (1/3 core of fload) and 23.12 X 10P6 BTU /HR for full core of fload, represent the heat generated at the completion of fuel transfer.
In bo th cases, the time to reach 150 degrees Fahrenheit is measured from the start of fuel transfer, with the fuel bundles being offloaded at the same rate for each case (20 bundles per day).
Consequently, the heat load rate of increase is the same in each case and the time of 7.3 days to reach 150 degrees Fahrenheit is the same for both cases.
At the time 150 degrees Fahrenheit is reached, fuel transfer is in progress in each case, since the time to complete normal refueling (1/3 core of fload) is approximately 13 days at the normal (20 bundle per day) fuel transfer rate.
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January 30, 1986 Docket Nos. 50-277 50-278 ATTACHMENT A Page 2 of 2 Question #2-i On page 3-15 it states that the time for the pool to reach boiling at 212 degrees F is "82 hours9.490741e-4 days <br />0.0228 hours <br />1.35582e-4 weeks <br />3.1201e-5 months <br />" af ter core of floading; yet, 3-20, (4)(d) states 27.5 days".
Is there a discrepancy?
Response to Question 2 The "82 hours9.490741e-4 days <br />0.0228 hours <br />1.35582e-4 weeks <br />3.1201e-5 months <br />" to boil on page 3-15 is dif ferent f r oti the 27.5 days" to boil on page 3-20 because the "82 hours9.490741e-4 days <br />0.0228 hours <br />1.35582e-4 weeks <br />3.1201e-5 months <br />" is based on no heat exchangers available while the "27.5 days" is based En having one heat exchanger in service.
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January 30, 1986 Docket Nos. 50-277 50-278 ATTACHMENT B Responses to Request for Additional Information - January 30, 1986 Peach Bottom Atomic Power Station Units 2 And 3 Installation of New Spent Fuel Racks ATTACHMENT B o
Page 1 of 1,
Response to r eques t for evaluation of spent fuel pool boiling
January 30, 1986 Docket Nos. 50-277 50-278 ATTACllMENT B Page 1 of 1 Request:
" Evaluate the offsite dose rate consequences of allowing the spent fuel pool to boil".
==
Conclusion:==
A parametric evaluation of the of fsite dose ef fects of a boiling spent fuel pool at Peach Bottom has been completed.
This evaluation is based on the spent fuel pool boiling analysis performed for Limerick as presented in LGS FSAR Section 9.1.3, modifying the araumptions as necessary to ref le ct the dif ferences betwer.n the two plants such as:
atmospheric dispersion f actors, pool water volume, maximum decay heat, and time to boil.
No basic changes were made to the model.
The results of this evaluation show that the resultant worst-case offsite thyroid dose from a boiling spent fuel pool at Limerick was determined to be 0.375 rem..
Based on the paramet ric evaluation, the Peach Bottom results are only 83% greater than the results of the Limerick calculations.
Therefore, the expected Peach Bottom of fsite dose is well below the guideline value of 300 rem stipulated in 10 CFR, Part 100.