ML20198J527
| ML20198J527 | |
| Person / Time | |
|---|---|
| Issue date: | 12/23/1998 |
| From: | Marsh L NRC (Affiliation Not Assigned) |
| To: | Modeen D NUCLEAR ENERGY INSTITUTE (FORMERLY NUCLEAR MGMT & |
| References | |
| PROJECT-689 GL-96-06, GL-96-6, NUDOCS 9812300207 | |
| Download: ML20198J527 (7) | |
Text
- . ! o Mr. David J. Modeen December 23, 1998 Director, Engineering Nuclear Generation Division Nuclear Energy Institute 1776 i Street, NW, Suite 400 Washington, D.C. 20006
Dear Mr. Modeen:
The NRC staff has reviewed the draft plan for developing a Technical Basis Report (TBR) to address the waterhammer issue discussed in GL 96-06, which was included as an enclosure to your letter dated December 7,1998. We discussed the draft plan with Mr. Kurt Cozens of your staff, Mr. Vaughn Wagoner of Carolina Power and Light, and other industry representatives during a meeting that was held here at the NRC Headquarters on December 10,1998. In general, we find the plan to be well structured, and the RAI Resolution Table 6 ittachment A of the plan) was very helpfulin correlating waterhammer issues with TBR tasks. Because the plan ,
is quite ambitious and resources are limited, we recommend that : ou prioritize your efforts by performing a Phenomena identification and Ranking Table (PIRT) review, or a similar .
approach. The use of PRA was mentioned but not well defined in the draft plan, and we feel that it is important to understand what role PRA will play in order to better define program priorities and specific tasks to be completed. Finally, when preparing the TBR, care should be taken not to extrapolate beyond what can reasonably be supported by the available information, recognizing (for example) limitations due to sample size, data scatter, scaling effects, and modeling. These and other aspects of the draft plan for developing a TBR for waterhammer
- were discussed during the December 10 meeting. A complete listing of our comments is included in the enclosure. Based on our review of the draft plan, we are very much encouraged by this industry initiative and hopeful that it will yield important insights into the resolution of ,
' waterhammer issues. I I
Sincerely, ,
I' Ledyard B. Marsh, Chief Plant Systems Branch Division of Systems Safety and Analysis ;
Office of Nuclear Reactor Regulation )
I
Enclosure:
As stated l
l i roject No.: 689 l DISTRIBUTION: Central File ASerkiz BWetzel GHammer GHolahan LBMarsh GHubbard JETatum SPLB R/F PDR l SMagruder TEssig .
l DOCUMENT NAME: G:\SECTIONA\TATUM\WHPLAN.COM *See previous concurrence l SPLB:DSSA SPLB:DSSA DRPM:N SPLB:DSSAf I
- JTatum:lk:rmc* GTHubbard* TEssig . LBMarsh Ib l 12/ 21 /98 12/ 21/98 12/f1J9 12/4 /98 l o 3 excel log # l3o OFFICIAL RECORD COPY I 9812300207 981223 l PDR REVGP ERONUMRC PDR 257 p p y 6isg pdl69 - - i y/
1
a Mr. David J. Modeen Director, Engineering
- Nuclear Generation Division pr Nuclear Energy Institute 776 i Street, NW, Suite 400 /-
'v shington, D.C. 20006
/
SUBJ T: WATERHAMMER TECHNICAL BASIS REPORT /
The NRC s has reviewed the draft plan for developing a Technical Basis R'eport (TBR) to address the w erhammer issue discussed in GL 96-03, which was includdd as an enclosure to your letter date ecember 7,1998. We discussed the draft plan with Mr. Kurt Cozens of your staff, Mr. Vaughn agoner of Carolina Power and Light, and other industry representatives during a meeting thas as held here at the NRC Headquarters on December 10,1998. In general, we find the p!a to be well structured, and the RAI Resolution Table (Attachment A of '
- the plan) was very helpfo correlating waterhammer issues with TBR tasks. Because the plan is quite ambitious and resou s are limited, we recommend that you prioritize your efforts by performing a Phenomena Ide ation and Ranking Table (PIRT) review, or a similar approach. The use of PRA was ntioned but not well defined in the draft plan, and we feel that it is important to understand wSat role PRA will play in ord3r to better define program j priorities and specific tasks to be comkted. Finally, when preparing the TBR, care should be taken not to extrapolate beyond what caNreasonably be supported by the available information, recognizing (for example) limitations due tdwample size, data scatter, scaling effects, and j modeling. These and other aspects of the dr plan for developing a TBR for waterhammer were discussed during the December 10 meeti A complete listing of our comments is included in the enclosure. Based on our review of x the draft plan, we are very much encouraged by this industry initiative and hopeful that it will yield ' portant insights into the resolution of waterhammer issues.
f Sincerely,
, ,' Ledyard B. Marsh,hhief
/ Plant Systems Branck Division of Systems Saf y and Analysis
- Office of Nuclear Reacto Regulation
Enclosure:
As states \ ;
. Project No.: 689 DISTRIBUTION. Central File ASerkiz BWetzel GHammer G. olahan j
/ LBMarsh GHubbard JETatum SPLB R/F PD ;
,/
SMagruder TEssig l
\
/
DOCUMENT NAME: G:\SECTIONA\TATUM\WHPLAN.COM i
/ 1 SPLB:DSSA SPLB: DSS DRPM:NRR SPLB:DSSA JTatum:lk GTHubbar TEssig LBMarsh A2/1) /98 12/.2//98 12/ /98 12/ /S8
/ excel log # l30 OFFICIAL RECORD COPY 1
l**
p pn og O \ UNITFD STATES g ; NUCLEAR REGULATORY COMMISSION o
- WASHINGTON D.C. 20665 4001
- ,o December 23, 1998 Mr. David J. Modeen Director, Engineering Nuclear Generation Division tluclear Energy institute 1776 l Street, NW, Suite 400 Washington, D.C. 20006
Dear Mr. Modeen:
The NRC staff has reviewed the draft plan for developing a Technical Basis Report (TBR) to Lddress the waterhammer issue discussed in GL 96-06, which was included as an enclosure to your letter dated December 7,1998. We discussed the draft plan with Mr. Kurt Cozens of your staff, Mr. Vaughn Wagoner of Carolina Power and Light, and other industry representatives during a meeting that was held here at the NRC Headquarters on December 10,1998. In general, we find the plan to be well structured, and the RAI Resolution Table (Attachment A of
) the plan) was very helpful in correlating waterhammer issues with TBR tasks. Because the plan is quite ambitious and resources are limited, we recommend that you prioritize your efforts by performing a Phenomena Identification and Ranking Table (PIRT) review, or a similar approach. The use of PRA was mentioned but not well defined in the draft plan, and we feel that it is important to understand what role PRA will play in order to better define program priorities and specific tasks to be completed. Finally, when preparing the TBR, care should be taken not to extrapolate beyond what can reasonably be supported by the available information, recognizing (for example) limitations due to sample size, data scatter, scaling effects, and J modeling. These and other aspects of the o aft plan for developing a TBR for waterhammer were discussed during the December 10 meeting. A complete listing of our comments is included in the enclosure. Based on our review of the draft plan, we are very much encouraged l by this industry initiative and hopeful that it will yield important insights into the resolution of waterhammer issues.
Sincerely, e n .,,L Ledyard B. Marsh, Chief Plant Systems Branch Division of Systems Safety and Analysis Office of Nuclear Reactor Regulation
Enclosure:
As stated 1
I Project No.: 689 .
l l
Nuclear Energy Institute Project No. 689 cc: Mr. Ralph Beedle Ms. Lynnette Hendricks, Director Senior Vice President Plant Support and Chief Nuclear Officer Nuclear Energy Institute Nuclear Energy Institute Suite 400 Suite 400 1776 l Street, NW 1776 i Street, NW Washington, DC 20006-3708 Washington, DC 20006-3708 Mr. Alex Marion, Director Mr. Charles B. Brinkman, Director Programs Washington Operations Nuclear Energy institute ABB-Combustion Engineering, Inc.
Suite 400 12300 Twinbrook Parkway, Suite 330 1776 i Street, NW Rockville, Maryland 20852 Washington, DC 20006-3708 Mr. David Modeen, Director Engineering Nuclear Energy Institute Suite 400 1776 l Street, NW Washington, DC 20006-3708 )
i Mr. Anthony Pietrangelo, Director Licensing Nuclear Energy institute l Suite 400 1776 l Street, NW Washington, DC 20006-3708 Mr. Nicholas J. Liparulo, Manager ;
Nuclear Safety and Regulatory Activities Nuclear and Advanced Technology Division Westinghouse Electric Corporation l P.O. Box 355 Pittsburgh, Pennsylvania 15230 Mr. Jim Davis, Director Operations Nuclear Energy Institute Suite 400 1776 i Street, NW Washington, DC 20006-3708 i
l j
s*
ENCLOSURE j
Comments Regarding a Proposed Technical Basis Report for l Addressing Waterhammer Concerns Associated with GL 96-06 i
General Comments. :
- 1. The draft program plan is challenging and perhaps overly optimistic in achieving the goals !
outlined in Attachment A, *RAI issue Resolution." Nonetheless, the development of a Technical Basis Report (TBR) provides a useful vehicle to address the waterhammer issues that have been identified, and this initiative should extend the knowledge base that is currently available for addressing waterhammer issues. NEl should be encouraged to prc:eed with this work, with the understanding that the outcome and application of experimental results will be judged as it is developed and shared with the staff.
- 2. The RAI Issue Resolution Table (Attachment A of the plan) is very useful and should be integrated into the TBR to facilitate closure of specific RAI questions.
- 3. A Phenomena identification and Ranking Table (PIRT) review, or similar approach, may be useful in focusing the plan and prioritizing actions to be completed, and is highly recommended. 1
- 4. The use of PRA is mentioned but not explained very well. It is important to understand at ,
the onset how PRA will be used because this information could influence how the plan is !
I focused and what testing is needed.
- 5. The TBR should recognize the limitations that exist in the data and information that is ultimately obtained, and not make more of the information and data than what is there. For example, there are limitations due to time and scale that need to be considered, limitations due to the small number of data points that may be available in some cases, and limitations duf., to modeling, data scatter, and applicability of information. To illustrate: because the event scenario is one that occurs over a very short period of time, the thermal inedia effects of the piping system and two-phase flow effects are likely to be very important. While these effects can not be disregarded, they will be difficult to model.
- 6. Time-dependent analyses which can be bench marked against experiments would be extremely useful.
The following specific comments are provided for your use.
Task 1.2 Assembly of system descriptions is very worthwhile, and can help in focusing the this effort.
Task 1.3 It is not clear how PRA will be used in this effort, and it is important to understand and develop this at the onset in order to better focus the work that needs to be done.
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- o -
's 2
Task 2.1 Excellent goal- a compilation of water hammer occurrences in containment cooling systems, underlying causes and corrective actions taken to prevent or minimize future occurrences would benefit both the staff and the licensees. However, it is not clear why it is appropriate to defer data collection until after the column closure (or pump startup with voided lines) tests are completed. Are such tests really needed?
Task 3.1 Defining the waterhammers and establishing a checklist of containment cooler system configurations that may be susceptible is a great starting point for selecting the experimental arrangements, defining test protocol, and defining plant applicability.
Task 3.2 Another great idea. Similar comments apply as shown for Task 3.1.
4 Task 4 Condensation induced waterhammer will likely introduce the highest loads.
However, Task 4 elements and deliverables have broader application beyond containment cooling systems, and licensees may find this work useful in addressing waterhamrner concerns associated with other systems.
Task 4.2 Developing a closed form analysis method to define behavior of a fluid system in a horizontal pipe, for purposes of predicting waterhammer occurrence is a extremely challenging goal. The parameters suggested for a closed form solution appear to be better suited for developing a correlation that may be useful for some applications.
However, the small number of experimants that are identified raises the question of statistical significance, uncertainty bounds, etc.
Task 4.3 The description is general and conceptually understandable. Attachment B is a typical writeup of test arrangement, instrumentation, test protocol, etc. However, the writeup sounds like a decision was made to run a few tests without giving due consideration to the parameters that need to be measured. Tasks 4.4 and 4.5 support this perception.
Task 4.4 More tests but no description of parameters sought, additional information to be gained, or how such information will be applied.
Task 4.5 What is different in this subtask from subtask 4.27 Task 5.1 Nice sounding goal, but lacking details. For example, how will scaling issues be addressed, and how will results be applied?
Task 6.1 Reference is made to previous Altran testing, and testing by other labs is introduced.
Does this mean a composite database will be developed? Information from actual events that have occurred should be included.
3 i
3 i t
Task 6.2 More testing in Altran's facility, and more data. How does it fit into closure of questions, modeling, etc.? Physical phenomena discussed in Attachment D are very complex, interactions will be control l3d by test configuration and test protocol. Page i 18 (Attachment C, paragraph 2) discusses thermal layering, etc. How will a closed form solution be extracted from these tests? In addition, the expert panel meeting that was held in Boston is noted at the top of page 19. Does this discussion represent the results of tha; meeting, or are there minutes that summarize
- conclusions from the expert panel and that better define how the goal in the last
. sentence will be met?
Task 6.3 The discussion identifies an iteration between RELAP or Method of Characteristics l' calculations. Not enough information is provided to understand the criteria that will be used to address differences between experimental results and " code" runs. What is the real thrust of this subtask ?
Task 7.1 What are the piping systems to be analyzed? Are iney the same as discussed in subtask 1.27 Tasks 7.2, 7.3, 7.4 This effort appears to be entirely analytical. Bench marking against some actual i data should be considered. In addition to amplification and attenuation, piping l layout, supports, flexibility, etc., are interactive and require sophisticated piping support codes to calculate. Is the Wiggert methodology (introduced in Task 7.1) capable of doing all of this?
t
- Task 8.1 This is a very important task, particularly identification of industry methods to calculate piping and support loads.
l
- Task 8.2 Comparison of margins between calculated load and loads determined by test is
- cited. What piping system tests will be used? ,
Task 9.1 To summarize "at the end" lessons leamed would seem to be too late in the process.
A review process at the front end, like a Phenomena identification and Ranking Table (PIRT) review, could be very helpful in focusing this effort and avoiding many of the " lessons learned" that will result. PIRT panels have proven their worth in other i i experimental / analytical programs. j Task 9.2 Shouldn't this be done at the onset? Has it been done? A PIRT panel (discussed above in Task 9.1) could assist in this task.
Attach. A The descriptions in the right hand column of the RAI Issue Resolution Table (Attachment A) seem optimistic and in some cases are not explained very well.
Nonetheless, Attachment A should be retained since it brings together RAls and program results in a concise form.
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