ML20039E721
| ML20039E721 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 11/20/1979 |
| From: | Voglewede J Office of Nuclear Reactor Regulation |
| To: | Silver H NRC |
| Shared Package | |
| ML111090060 | List:
|
| References | |
| FOIA-80-515, FOIA-80-555 NUDOCS 8201110229 | |
| Download: ML20039E721 (3) | |
Text
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November 20, 1979 eg, *....f NOTE T0: Harley Silver, Project Manager TMI-l Restart FROM:
John toglewede, DSS /CPB
SUBJECT:
SECOND-ROUND QUESTIONS ON TMI-l RESTART SUBMITTAL Attached are second-round questions on the TMI-l Restart Report as requested by your memorandum of November 16, 1979. Gerry Wermiel and I are the only reviewers with input on Lessons Learned items as of today.
I understand more input may be
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coming.
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John C. Voglewede Core Performance Branch cc:
G. Wermiel P
4 DgN80-515
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s ROUND-TWO QUESTIONS ON TMI-l RESTART REPORT 1.
Assure that your definition of " Safety Grade" in Section 1.4 of the Restart Report, which identifies " redundancy" as a required feature, meets NRC single failure criteria including separability.
2.
The following additional infonnation is required concerning NUREG-0578 item 2.1.5.c.
Hydrogan Recombiners*
a.
70u indicate that you have performed hydrogen generation rate calculations in accordance with Regulatory Guide 1.7 inorder to verify that adequate time is available following an accident to install the second recombiner and still maintain the containment atmosphere hydrogen cocentration within acceptable limits. Submit these calculations for our review.
Indicate where the second hydrogen recombiner is to be stored prior to being used, and verify that adequate procedures are avaiiable and training perfonned to assure that the second recombiner can be properly and expediously installed.
b.
You indicate that you will perfonn an evaluation to demonstrate that potential leakage and discharge to the atmosphere of the Intennediate Building air used for recombiner cooling will not result in off-site dose releases in excess of 10 CFR 100 limits.
Submit this evaluation for our review.
3.
The Met-Ed response to Question 17 (Supplement 1 to the TMI-l Restart Report) identifies loss of natural circulation due to loss of heat sink as a condition to be analyzed for inadequate core cooling response. This analysis meets the requirements of NUREG-0578 but does not correspond to the analysis (DNB transient at power) proposed at the September 13, 1979 B&W Owner's Group meeting.
Please identify those analyses of inadequate core cooling which will be performed independently, or in verification, of the generic analyses to be provided by Babcock & Wilcox.
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4.
As requested by Question 18 (Supplement 1 to the TMI-1 Restart Report), please identify those emergency procedures which require the explicit use of a) in-core l
thermocouples, b) wide range reactor outlet temperature measurement, c) reactor coolant saturation temperature margin, and c) other instrumentation identified in the response to Question 17 of tk Supplement.
Identify each instrument class separately 5.
As requested by Question 20 (Supplement 1 to the TMI-l Restart Report), please complete the description of the proposed subcooling meter.
Include:
a.
Overall display uncertainty b.
Display qualification c.
Infonnation from page 2 of Table 20-1 (omitted from Submittal)
If the device utilizes an analog steam table approximation as stated, describe the process in. sufficient detail to verify the applicability of the method.
Include range and accuracy of the procesh 6.
Paragraph 2.1.3.b of NUREG-0578 requires a description of further measures and supporting analyses that will yield more direct indication o_f_ low reactor coolant f
level and inadequate core cooling such as reactor vessel water level instru-mentation. Section 2.1.1.6 of the Restart Report does not address further measures (to be implemented by January 1,1981), nor does it address the a
question of reactor vessel water level instrumentation.
Provide a conceptual description of what additional measures will be taken to detect inadequate core cooling.
Provide an; implementation schedule for these changes.
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