ML20040E228
| ML20040E228 | |
| Person / Time | |
|---|---|
| Issue date: | 11/12/1981 |
| From: | Catton I Advisory Committee on Reactor Safeguards |
| To: | Savio R Advisory Committee on Reactor Safeguards |
| References | |
| TASK-A-45, TASK-OR ACRS-CT-1391, NUDOCS 8202040025 | |
| Download: ML20040E228 (2) | |
Text
//ja H9-31 LOS ANZsLas: 3CEOOL OF ENGINEERING AND APPUED SCIENCJ 0I-/39/
.g MEMORANDUM 12 Nov 1981 TO:
R.P. Savio
(
FROM:
Ivan Catton N
SUBJECT:
Task Action Plan A-45
" Shutdown Heat Removal Requirements" I have reviewed Task Action Plan A-45 on shutdown heat removal require-ments. The plan is mostly common sense.
I cannot understand why it is a four-year project nor why there may be trouble staffing it.
It seems to j
me that DHR is another way of saying safety and that it should be the focal point of a number of projects now underway.
The plan appears to be equipment oriented. I believe that TMI demon-strated that the equipment is pretty much satisfactory. A broader view of DHR is needed. More consideration needs to be given to the operator, his control room and information available to him, to insure that the proper de-cisions are made. Work at EPRI by Alex Long has demonstrated that some operat-ing crews are much bettee than others in "getting the energy out of the core."
Brief comments on some of the Sub-Tasks follow.
Sub-Task 1.
Develop Interim Acceptance Criteria for Assessment of DHR Systems This is a necessary step.
In this task, I would hope that credit will be given to systems that can be repaired or augmented within a time period appropriate to a given need.
Sub-Task 2.
Develop Means for Imorov_ement of SDHRS Part 2.1 of this sub-task is devoted to phenomenological studies.
This area is the focal point of RES thermal hydraulic studies. Semiscal e, FIST and other such facilities operate in support of needs in the thermal hydraulic area as perceived by RES. The information needed should be avail-able or easily obtained.
j Part 2.2, Conceptual Design Studies, should be more than just another -
series of paper studies. Many ideas and studies exist (the S. Levy Inc.
i studies of BWRs funded by EPRI). Having an A and E study a few selected schemes will be a worthwhile effort. Possible solutions such as " feed and bleed" or " reflux condensation" are already receiving a great deal of atten-t i
tion. This part of Sub-Task 2 should determine whether or not studies such 8202040025 811112 PDR ACRS l
CT-1391 PDR UNivsRs TY OF CAMFORNIA--(tattertand for totardepartmental m
o 145 ANOB128: SCEOOL OF ENGDtEERING AND APP 1JED SCIENCE
.1 4
Task Action Plan A-45 cont'd as the EPRI study of flow through valves are adequate. There is no specific mention of passive systems.
Part 2.3, Operational Aspects of Alternative SDHR Systems, is very good as far as it goes. What is missing is a study of existing systems to see if improvements in their operational characteristics could be achieved through fewer and/or better valves, improved feedback to the operator and better operator training. Without such a task clearly called out, Sub-Task 2 is incomplete, as an upgraded better understood system is clearly an al-ternative SDHR for future use.
i Sub-Task 3.
Assessment of Adequacy of DHRS in Existing and Future LWRs I would hope that this task would include a study of the operator and his training, the control rocm, instrumentation and signal processing equip-ment as well as the DHRS. The type of studies being conducted by EPRI are relevant here (see EPRI NP-1982, Aug. '81, " Evaluation of Proposed Control Room Improvements Through Analysis of Critical Operator Decisions"). A part of Sub-Task 3 might be titled " Evaluation of Proposed or Existing DHRS Through Analysis of Critical Operator Decisions." Sub-Task 3.5 (Assessment on a Deterministic Basis) is very important as it will give l
balance to NRCs PRA work.
Sub-Task 4, Development of Design Proposals I would recommend three additional parts to this task:
Sub-Task 4.3--Develop operator training programs and cost estimates for both selected and future LWRs.
Sub-Task 4.4--Develop augmented control room designs and cost esti-mates for both selected and future LWRs.
Sub-Task 4.5--Develop augmented control room computer software and cost estimates for both selected and future LWRs.
1 4..
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I UNIVERSITY OF CALIFORNIA--(hteerbead for laterdepartansatal ums)