ML20206H448
| ML20206H448 | |
| Person / Time | |
|---|---|
| Issue date: | 04/10/1987 |
| From: | Kniel K Office of Nuclear Reactor Regulation |
| To: | King T, Speis T, Williams P NRC |
| References | |
| NUDOCS 8704150359 | |
| Download: ML20206H448 (6) | |
Text
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MEMORANDUM FOR:
Distribution FROM:
Karl Kniel, Chief Safety Program Evaluation Branch Division of Safety Review and Oversight
SUBJECT:
MEETING WITH DOE TO REVIEW CHAPTER 5 0F MHTGR PRELIMINARY SAFETY INFORMATION DOCUMENT (PSID)
The subject meeting is the fourth of a series of meetings with DOE and its contractors to discuss NRC comments on the conceptual design for the modular HTGR. The meeting will be held on April 22, 1987 and on April 23, 1987 in l
Room P-110 and begin at 9:00 a.m. on both days.
An agenda is enclosed.
Chapter 5 deals with the reactor vessel and heat removal systems and is divided into the following sections:
5.1 Introduction, 5.2 Vessel System and Subsystems, 5.3 Heat Transport System and Subsystem, 5.4 Shutdown Cooling System and Subsystems, and 5.5 Reactor Cavity Cooling System.
Reviewers for Chapter 5, together with contractors from ORNL and BNL, should plan to meet in Tom King's office at 1:00 p.m. on April 21, 1987 to discuss their planned comments on the subject document.
If you have any questions please contact Pete Williams, the Project Manager (x29613).
wa creca b7.
Karl Eniel Karl Kniel, Chief Safety Program Evaluation Branch Division of Safety Review and Oversight
Enclosure:
As stated I
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0FFICIAL RECORD COPY
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DISTRIBUTION:
Central File SPEB R/
DSR0 C/F TSpeis PWilliams TKing RColmar CAllen MEl-Zeftawy, ACRS/H-1016 RJohnson/Rm. 212 LSoffer/Rm. 266 DThatcher/Rm. 212 WMorris/NL-007 EChelliah/Rm. 244 JRead/Rm. 266 JSwift/Rm. 244 KHeitner/P-234 WKennedy/AR-5209 DJones/AR-5209-LBeltracchi/P-700 GVanTuyle-BNL SBall-0RNL RLandry/Rm. 266 JWilson/Rm. 544 JFlack/NL-007 RSenseney/EWS403 TiPro het R11u16721,18 D[ h ZRosztoczy/Rm. 266~g POR i
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k AGENDA April 22, 1987 Meeting on MHTGR PSID Chapter 5 (Phillips Building; Room P-110) 4 1
l 9:00 a.m.
Opening Remarks - NRC, DOE, Others 9:15-10:30 a.m.
Vessel & Heat Removal System Overview-GA Outline Presentation
- ' Summary Descriptions 1
Overall Design Requirements Operating Modes and Sequences t
Overall Normal Operating Performance 4
Decay Heat Removal Performance Key Licensing Basis Events Overview to include a summary of the role of the Technology Development Plan and past operational experience in achieving the objectives of the Vessel and Heat Removal System.
10:30-12:00 p.m.
Reactor Cavity Cooling System (RCCS)
BNI I
Requirement for RCCS Design Configuration i-Normal Operating Performance Response to LBEs a
]
Applicable Codes / Standards, RGs l
Additional Topics to be included in presentations or to be discussed:
I 1.
Response to NRC comment G-8c.
2.
Proposed ISIT objectives and means to achieve these objectives.
1 l
3.
Needs and possible plans for full or partial scale performance verification experiments to address such concerns as duct blockage scenarios and startup and wind-induced stagnation possibilities.
l 4.
Uncertainties associated with RCCS performance, includ-ing degraded performance sensitivity studies and conse-quences of total system failure (DOE's position on heat i
transport to surrounding earth and utilization of j
" earth heatup" cooling capabilities).
1 5.
Sensitivity of shutdown heat removal systems' perform-ance to the uncertainties in after heat.
NOTE:
Limiting case performance scenarios should be presented and discussed in the form of detailed temperature pro-files that begin with the reactor silo and proceed in-ward to the core and include fuel particle temperatures.
12:00-1:00 p.m.
LUNCH 1:00-2:00 p.m.
Comments by NRC and Discussion 2:00-3:30 p.m.
Vessel System & Subsystems CE Requirements for Vessel System Overall Design and Performance of Vessel System Overall Response to LBEs Design & Performance of Vessel & Duct System Key Requirements Design Configuration Design Performance & Response to LBEs Applicable Codes / Standards, RGs Design & Performance of Vessel Support Subsystem
- Key Requirements Design Configuration Design Performance & Response to LBEs
- Applicable Codes / Standards, RGs Design & Performance of Pressure Relief Subsystem Key Requirements
- Design Configuration Design Performance & Response to LBEs
- Applicable Codes / Standards, RGs Presentation to include responses to NRC comments G-8A and G-8B.
In addition, DOE should be prepared to discuss the uncertainties associated with the vessel system tempera-tures and performance, the basis for these uncertainties, the sensitivity of plant safety to these uncertainties, potential mechanisms and probabilities for cross duct failure, multiple vessel failures that could lead to sustained air ingress, the consequences to the vessel system from large water ingress, potential uncertainties in establishing the NDTT shift including suitability of the University of Buffalo reactor for irradiation of test specimens, sustained vessel operation at temperatures above current code limits, and safety classification of the relief valve interlock.
3:30-5:00 p.m.
Comments by NRC and Discussion l
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l April 23, 1987 Continued Meeting on PSID Chapter 5
).
9:00-10:30 a.m.
Heat Transport System (HTS) & Subsystems GA 4
Requirements for HTS i
Design &' Performance of HTS Overall Response to LBEs Design & Performance of Main Circulator GA
.l Key Requirements Design Configuration Design Performance & Response to LBEs
-. Applicable Codes / Standards, RGs F
Design & Performance of Steam Generator CE j
Key Requirements j
Design Configuration Design Performance & Response to LBEs Applicable Codes / Standards, RGs Presentation to emphasize features of the design, the i
development program, ISIT, and administrative controls that (1) minimize challenges to reactor safety. systems, l
and (2) minimize the potentials for causing or aggravating an accident.
Discussions shuuld include potentials and consequences from missiles generated by circulator dynamic failure, thermal transients if circulator fails to shutdown (PSID 5.3-9), uncertainties associated with the j
hot / cold streak conclusions given on page 5.3-11), a review of the reasons supporting the safety classification j
of the moisture detection system and the steam generator, the design features of the steam generator provided to seet ISI requirements, multiple tube or tube sheet failure l
consequences, and scenarios when primary pressure is higher than secondary pressure.
l 10:30-11:30 a.m.
Shutdown Cooling System (SCS) & Subsystems GA Requirements for SCS l
Design & Performance of SCS i
Overall Response to LBEs Design & Performance of SCS Circulator GA Key Requirements l
Design Configuration Design Performance & Response to LBEs i
Applicable Codes / Standards, RGs i
Design & Performance of SCS Heat Exchanger CE Key Requirements 1
Design Configuration i
Design Performance & Response to LBEs 4
Applicable Codes / Standards, RGs t
.i
o 2
Design & Performance of Shutdown Cooling Water BNI Subsystem Key Requirements Design Configuration Design Performance & Response to LBEs Applicable Codes / Standards, RGs Presentation and discussion emphasis should be similar, where appropriate, to HTS.
Discussions should include probabilities and consequences of radioactive releases via the shutdown cooling water subsystem.
11:30-12:30 p.m.
LUNCH 12:30-2:00 p.m.
Comment by NRC and Discussion i
2:00-3:00 p.m.
General Discussion and Discussion of Administrative Items 1.
Clarification of design information if not provided earlier.
2.
Comments on DOE's responses in Amendments 1 and 2.
3.
Discussion of ground rules for utilization of information classified as " Applied Technology" or proprietary in the NRC's formulation of its Safety 4
Evaluation Report.
4.
Other s