ML20217E845
| ML20217E845 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 10/01/1997 |
| From: | Kelly G NRC (Affiliation Not Assigned) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9710070250 | |
| Download: ML20217E845 (42) | |
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t NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 206 % 4001
'4 4 . . . . . ,et October 1,1997 NOTE TO: Information and Records Management Branch Office ofInformation Resources Management FROM: Glenn B. Kelly, Senior Project Manager 2 /// ,
Project Directorate 3-3, DRPW, NRR d4ts .
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SUBJECT:
INFORMATION TO DE PLACED ON THE DUANE ARNOLD ENERGY l- CENTER (DAEC) DOCKET (50-331) 1 The enclosed information was provided to me by IES Utilities Inc., employees during
( discussions we had regarding questions the staff had about discrepancies between the UFSAR and how the licensee operated the spent fuel pool during core offloads a7d fuel shuffles. Please place the enclosed information on the DAEC docket.
cc: Public Document Room '/k PD33 reading file WOf 1
i 9710070250 971001 PDR ADOCK 05000331 P PDR
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h DAEC 3377 DAEC Rd Palo,IA $2334 UTILITIES Memorandum TO Bob Murrell ;
FROM: Terry L. Lanch DATE: October 18,1996 RE: Duane Arnold Energy Center
SUBJECT:
Refueling Outage 14 Risk Assessment Support Attachments:(1) Final Shutdown Risk Report for RF014, DAEC memo NG-96-1729 (2) PRA Today newslettter (3rd quarter 1996 for DAEC)
(3) Management Review Meeting handout for RF014 Week 3 (4) RF014 Outage Meetings adgenda (5) Day Shift Turnover handout for 10/15/96 (6) Outage Risk Profile, based on scheduled work as of 10/15/96 (7) Outage Defense-in-Depth, based on scheduled work as of 10/15/96 (8) Daily Focus newsletter for October 15,1996 (9) Shutdown Decay IIeat Validation As you requested, I nave gathered the attached materials for you to submit to Glenn Kelly. I hope he finds it useful.
Introduction The attached material is for your information to help illustrate how the Risk Assessment Group at the Duane Arnold Energy Center is involved and assessing risk for the current refuel outage (DAEC RF014). The following description should provide you with some of the ways my group is involved with shutdown risk assessment at DAEC. The attachments are provided as illustrative examples.
Background
This outage we are using EPRI's Outage Risk Assessment and Management (ORAM) software to perform the risk evaluations for defense-in-depth (qualitative risk) and for probabilistic safety (quantitative risk). We have developed plant-specific models for use this outage. They were developed collaboratively between consultant and in-house resources. Extensive reviews have been made to the models, including baselining a schedule from the previous refuel outage in ORAM and comparison of those results with our extensive PSSA models used in RF013.
14Uuteview oLRI 014 l The PRA group has been involved in continuing reviews of the outage phn for RFol4 since its l Inception in February 1996. At that time we made a preliminary evaluation using ORAh! and fed back our insights to the schedulers in Outage hianagement who promptly made changes to the way work was being scheduled to climinate obvious risk issues from ORAh!. We also made another detailed evaluation in hiny, and then a final shutdown risk evaluation was made in Augu.t as the outage plan was being finallred for implementation. (See Attachment 1.)
Subsequent to the final SDR report, we have analyzed the outage schedule (system windows and major milestones) neatly each day through the end of September. Finally, we've created a PRA newsletter to educate the staff about PRA in general, but specifically our last issue deals with shutdown risk issues. (See Attachment 2.)
Concurrent to our evaluations and various discussions with sch-lulers and Outage hianagement personnel, we provided hands-on user training for the Shift L:.nnical Advisors that were designated to run ORAh! In the Control Room as necessary. Also, an overview of ORAh! was provided to the Safety Committee, Operations Conunittee, and each of four Operations crews.
Finally, hands-on training on ORAhi was provided to key personnel in Outage hianagement, Fire Protection Group, and the Risk Assessment Group.
11esides training, we have been extensively involved in various outage meetings prior to and during the refuel outage. Prior to the outage, we provided presentations to the hinnagement icview Team for each of the lookahead weeks. (See Attachment 3.) During the outage, we avend and provide presentations each shift at the Work Control Center, and our risk summary inh mation is provided as an attachment for discussion at the Control Room Shift Turnover and th. Plan-of-the-Day / Night meetings which we also attend. (See Attachment 4 7.)
Throughout the process we have been asked to evaluate "what if" scenarios and scheduling questions, and we've provided prompt responses due to ORAht't fast quantification ability.
Finally, during the power down and outage implementation, we provide input to the daily newsletter for mass distribution. (See Attachment 8.)
The ORAhi roftware is on limited distribution this outage, as it is not loaded on a computer network environment yet. We have taken extreme care to update the computers where ORA is loaded and used with a new outage schedule each shift (Sam and Spm) prior to various outage turnovers tha: take piace afterwards. This ensures that all ORAhi users have updated schedules as they are are available in real time. (This also means we must walk around a computer floppy disk each shift to all the machines.) We expect to have ORAh! installed and maintained on the computer network before RFO15.
Another large portion of our work for the outage is with regard to decay heat curves. hiy group is also responsible for issuing outage specific deesv heat curves (which include decay heat in the spent fuel pool from previous outages) to the Operations Department. These curves are "best estimate" calculations using the Wigner Way formula. We have made a good effort in collecting real plant data to validate our curves. Our belief is that they are very accurate.
(See Attachment 9.)
Conclusions I hope that the attachments give you an appreciation for the extent of our involvement and review of the evolution and implementation of the outage plan and shutdown risk issues, if you have any questions or comments, please contact me at extension ~1694.
. ;c,- A1 TACH MEMT _ L oxec 3277 OAEC Rd Pelo. IA $23M dW UTILITIES Memorandum TO: Phil Carlotta NG-96-1729 FROM: Terry L. Lanc <fA 1
l DATE: Augurt 15,1996 i
RE: Duane Arnold Energy Center SUBJECT Final Shutdown Risk Management Review for Refueling Outage 14 FILE: A 351, A 290b, A-18 References (1) IES Memorandum NG 961107, " Preliminary Shutdown Risk Management Review tw RF014," May 9,1996.
(2) Scheduling Information Obtained from OMS, dated August 14, 1996.
(3) IES Memorandum NG-96-0391, " Preliminary Shutdown Safety Review of the Outage Plan for RF014," February 15, 1996.
Attachments:(1) Safety Function Status (color) graphic for August 14,1996 data (2) RCS P. oiling Risk Profile for August 14,1996 data (3) " Final Safety Review of the DAEC RF014 Outage Plan" report At your request, I have delayed the analysis for this report until the Scheduling personnel have had the opponunity to update the outage schedule in OMS to account for the Noble Metals injection project, as well as to give Outage Management opportunity to review and refine the outage schedule before publishing it This memo closes out *.he August 15th (moved from July 25th) milestone t3 issue the Final Shutdown Risk Repon.
Introduction The purpose of this memo is to transmit the results of a review of the outage schedule dated August 14,1996 and the final results of the probabilistic evaluation of risk due to the planned work scheduled for Refueling Outage Founeen (RFO14) This evaluation represents our continuing review of the outage plan since February, and it confirms the basic conclusions reponed earlier in Reference i that the outage work is being scheduled in a safe manner, m I
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i Final Safety Review of the DAEC RF014 Outage Plan PART 1: Defense In Depth Evaluation using ORAM
'Ihe review of defense in depth for the fina! DAEC RFO14 outage plan was perfomted by mo ' cling the major milestones and system hammocks with the Outage Risk Assessment and Management (ORAM) software. ORAM is a computer tool sponsored by EPRI that can model refueling outage conditions, configurations, and activities which can impact overall safety of a
, nuclear power plant. ORAM takes into consideration plant specific outage plans (system 4amm'osks), operations practices, plant procedures, and plant system interdependencies and configu' rations, which must be input in the form of plant specific models (developed and maintained by risk engineers) and outage specific schedules developed by the plant schedulers.
Scheduling data was obtained by accessing the AS OMS mainframe scheduling software and downloading current dates and times for the various milestones and system hammocks.
The results communicated in this report are based on scheduling data that was obtained from the AS OMS system on August 14,1996. The ORAM models are developed to translate this data into a color display for several important safety functions for refuel outage considerationt. They are set up so that they approximate the colors determined from the " Shutdown Safety Assessment Checklist" from " Outage Risk Management Guidelines"(OMO 7). For purposes of abbreviating the discussion, " green" and " yellow" conditions will not be discussed. Additionally, several
. ORAM generated graphs are included. While these graphs and the acronyms used by ORAM are generally self explanatory, for purposes of abbreviating this report a full definition of these acronyms is not provided. Any questions about them can be directed to the Risk Assessment Group.
Maior Milestonen The major milestones that follow are important to put the overall outage schedule in perspective.
Turbine / Generator Offline October 11,1996 Cold Shutdown October 14,1996 Cavity Floodup and FP gates removed October 16,1996 B side Safety Window October 16-October 23,1996 Fuel Shuffle #1 October 17,1996 A Side Safety Window October 23 October 31,1996 Fuel Shufile #2 - Ociober 24 October 28,1996 FP gates installed and Cavity Drained October 30,1996 Startup Tests October 31 November 5,1996 Begin Plant Startup November 8,1996 m
J
. 'l Fin:tSafety Review cf the DMC RF014 Plan Defenst in Denth Evaluations Attached is a color graphic obtained directly from an ORAM screen. Please refer to the labeling on this graphic to correspond to the risk evolutions described below. Keep in mind the following ,
distinction in word choice. "in-operable" or "out of service" means this component or system is not capable of providing its intended safety function (and may be driven by administrative tag-outs or scheduling work hammocks). " Unavailable" is a more general term which means that the system or component is not available because either (1) the system / component itselfis not in service, or (2) some support system or component is not operable. The term " unavailable," in general, does account for the time associated with post maintenance tests, but may not account for the time associated with system operability testing, STPs, etc. The use of system hammocks provides a somewhat gross (conservative) estimate of defense in-depth; however, this also allows for greater flexibility in performing work within pre-determined windows.
The following is a breakdown of the important deterministic (defense-in-depth) safety function from the ORAM analysis.
Shutdawn Cooline for the Vessel This safety function shows a some " orange" throughout the outage, mainly early and late in the outage, it is recognized that the SDC function is the most critical and diflicult to manage one for the prevention of RCS boiling. The following is a breakdown by datcs for the plant states that are " orange" for SDC.
October 13 - October 16: " orange" Early in the outage decay heat is high. At least one tra!n of RHR SDC is required to remove this heat load. Per the schedule,2 RIIR trains (and their respective support systems) are maintained available up until the B side safety window. However, recirculation pumps are not available for forced circulation, if called upon, because of the RBCCW and GSW hammocks. RBCCW is used for pump seal cooling, and GSW is used for MG Sets cooling.
It remains orange until completion of cavity floodup and remoul of the Fuel Pool gates, when inventory is maximized and thus time to boll is longer.
October 17 October 19:" orange" Only one train of RHR-SDC is available during the B side safety window when decay heat is too high for the Fuel Pool Cooling system to provic'e sufficient independent backup capacity.
October 23 October 24: " orange" No RHR-SDC is available, however, decay heat is low enough that the FPC system is capable of decay heat removal by itself when both trains of FPC are running.
October 31t November 15: " orange" Various startup testing is being done. The LOOP LOCA test represents a "high risk evolution" for SDC and Inventory Control. The reactor hydro test window represents a "high 2
Th:1 Safety Review of I'r DAEC RT014 Plan risk evolution" in which SDC is " lost" momentarily but is easily recoverable upon test completion. The orange color for such tests is an indication to highlight the fact that these tests can represent a real challenge tc. the plant and warrant special attention.
Fuel Pool cooling to the Scent Fuel Poc1 This safety function appears to be well managed for defense in-depth during this outage. All patches are " green" or " yellow." To maintain this level of safety, temporary power supplies must be provided to either FPC train when SDC and electrical power may not be fully available.
Inventory Control l
l This safety function appears to be well managed for defense in depth during this outage. All l
patches tre " green" or " yellow."
AC Power control This safety function shows a some " orange" in the first third of the outage, ne following is a breakdown by dates for the plant states that are " orange" for AC Power Control.
October 16: " orange" This region of" orange" draws attention to the fact that switchyard work (i.e.,161/345 KV) is scheduled while the reactor cavity is not yet flooded up, llaving a shorter time to boll (when inventory is relatively low) could impact the safety significance of degrading defense in-depth for safety related electrical systems. Both the startup and standby transformers and both EDGs are available during this time, however.
IG GI October k7 October }91" orange" The reactor cavity is flooded at this time, but work going on concurrently includes switchyard work and Essential Bus I A4 is unavailable. % u1, /.olin E/M or) </t Gvu.
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Reactivity Control This safety function appears to be well managed for defense in depth. The yellow areas are when fuel movement is occurring, to represent the risks of fuel handling errors.
Containment Control This safety function appears to be well-managed for defense in-depth. The single patch of
" orange" on November 1 indicates a high risk evolution for containment testing. This color assignment helps to draw attention to such startup tests.
1 3
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..' ... j IkolSafety Merlew of the DM'C RFOH Han i ng{gane.in.Denth littnamendations Through the iterative process of schedule planning, evaluation, feedback, and revision, fewer l
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substantive and profound recommendations can be made. Even so, the following are what recommendations can be made:
While work is being performed in the switchyurd (activity Z0100!!, October 1619) the i standby and startup transformers should be safe guarded by restilcting traffle around those areas as much as is practical. Similarly, work on offsite power sources (lines, breakers, etc.)
to either transformer should be minimized to the extent practical.
During the early phases of the outage, when one train of SDC is necessary for decay heat removal, the operating train of SDC should be designated as a " protected system" to !
minimize the opportunities for personnel to inadvertently cause a loss of SDC event. Also, contingency ple.ns and procedures rega: ding loss of DliR events (e.g., IPOI 8, AOP 149)-
should be reviewed.11 ave plans ready to implement attemate DilR methods if SDC is lost <
,g (e.g., Fuel Pool Cooling SDC assist mode, recirculation pumps, feed and bleed). ,, dWd q j :p _.__.L ;
- During the middle phase of the outage, when both trains of RiiR.SDC may be unavailable doe to common SDC suction work, contingencies should be prepared or reviewed for situations in the event that one or both trains of FPC is lost.
- Proper temporary power supplies should be establish'ed and verified for the FPC system, i prior to commencing work on electrical systems that can disable the normal FPC power supplies.
During the containment testing phase (activity Z233011, November 1) secondary containment penetrations should be controlled to maximize secondary containment integrity, Procedures for containment closure should be reviewed and be consistent with those procedures for loss of DilR. These contingencies should consider environmental conditions of containment as well as the availability of electrical power.
During the reactor hydre testing phase (activity Z234011, November 1 5) the functionality of systems / components should be assured by post maintenance testing, by monitoring key parameters of the systems in service, or by verification ofline ups and administrative controls. Both trains of RiiR.SDC should be maintained available during such evolutions.
1 4
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rin:ISafety Rnlew of the DAEC RT014 l*lan PART 2: Probabilistle Shutdown Safety Assessment (PSSA) using ORAM The review of shutdown risks for the final RFO14 outage plan was performed by modeling the major milestones and system hammocks with the ORAhi software. ORAhi has two modes of operation one that calculates deterministic defense in depth, and one that calculates a risk histogram u ing probabilistic-oriented models, scheduling data was obtained by accessing the AS OhtS mainframe system software and downloading current dates and times for the various milestones and system hammocks. The results communicated in this report are based on scheduling data that was obtained fron: AS-Oh1S on August 14,1996. The ORAhi risk models translate this data into a risk profile similar to those communicated in previous shutdown safety assessments (i.e., RF012, RFOl3) which can be used to obtain additional risk insights that may not be obvious from the deterministic evaluctions described in Part I above.
l PSSA Evaluatiort The final quantitative probabilistic evaluation is believed to be conservative in absolute frequency and is still comparable to other BWR refueling outages. The absolute frequency profile is similar to the risk profile for RFOl3 for its planned duration, as is expected. Small variations within the profile are the result of the detail at which ORAhi allows (ORAhi evaluates changes in system availabilities down to the hour). The absolute average RCS boiling frequency for RFO14 is approximately 2.08E-6 events per hour.'
Attached is a histogram obtained directly from ORAhi. This graph illustrates the risk profile due to RF014 RCS Boiling Frequency, as was determined by the scheduling data obtained on August 14th.
Risk Profile Exnlained The attached histogram shows the probabilistic risk of boiling profile for RFO14, based on scheduling information from August 14,1996. In general, this risk profile looks similar to outage risk profiles for RFOl3 that were determined using different methodology and software.
ORAhi allows for more detailed varia% s within the major plant phases, therefore, it shows some minor peaks and valleys through:st the histogram.
Risk is typically highest at the start of the outage when decay heat is highest and vessel inventory is not yet maximized. Risk takes a large fall as soon as the cavity is flooded and FP gates are removed, thus making time to boil long because inventory is maximized. Risk increases as the fuel movement and the B side safety systems are being worked.
Risk takes another large drop as soon as decay heat is sufficiently low that two FPC trains are adequate for decay heat removal by themselves. (A second drop occurs on October 22nd, but this is due to a brief period when both trains of FPC and a single train of RHR-SDC are available for DilR,just prior to the common SDC hammock beginning.) Risk takes an increase during the 5
Fin:tSafety Review cf the DAEC RFoi4 l'lan common SDC suction line work. (Fuel movement during the second fuel shuftle is also a small contributor to this risk increase.)
Risk drops to its lowest point, as many safety systems are restored to service. Finally, risk increases as soon as reactor cavity is drained back down. This reduces the inventory available
, for bulk cooling, however, decay heat is relatively low. It is during this last phase of the outage, when all safety systems are expected to be available, that startup tests begin are scheduled to occur.
The reactor hydro test is an anomaly with regard to the startup tests, because at high pressure many of the initiating events that are postulated in the probabilistic models are temporarily precluded. (Therefore, the reactor hydro test appears to make risk decrease the way it is modeled in ORAM PSSA. Ilowever, note that in the deterministic side, color portion, of ORAM the reactor hydro test is highlighted in orange" as an activity that warrants special attention.)
Summary of Outage Phses Generator Ofline to Refiteling Cavity Flooded,0ctober 11-16 This time period represents the cool-down from hot shutdown to cold shutdown conditions, it also includes flood up of the cavity and removal of the drywell and reactor heads. System work is scheduled for RBCCW and OSW, and high pressure systems (i.e., Feedwater,11PCI, and RCIC). The risk of RCS boiling during this time period is Idghest mainly because decay heat is still relatively high and the amount of water (although increasing through cavity flood-up) is not maximized until October 16. A minimum of one SDC train is required for decay heat removal from the vessel. Risk during this period is initially dominated (Oct. Il-14) by SDC bypass events (valve mis alignment in the recirculation line which could potentially lead to SDC injection flow bypassing the core region and flow subsequently out the SDC suction),60%.
Thereafter, risk is dominated by SDC isolation events,65%.
B side Safety IVindow and Fuct Shuple #1,0ctober 16-October 17 This time period represents the B-side systems window where the bulk of the outage work is being done. Because the plant will be relying solely on the A-side safety systems (in addition to reliance on both FPC trains) while decay heat is still too high for both FPC trains alone risk of boiling is relatively high, but still much lower than in the previous phase because of the available
. Inventory for bulk cooling via the reactor cavity and spent fuel pool. Risk during this period is dominated by SDC isolation events (varies 25 50%), RPV isolation events (15 30%), and RPV draindown eventsT10f30%) Values in parentheses show variation within these outage phases.
~ ~ . -
B-side Safety IVindow Continued, October 17-October 23 This time period represents the first opportunity to use the FPC trains solely to provide shutdown cooling (deccy heat is sufficiently low that the heat removal capacity of the FPC trains is adequate). This is the main reason why risk of boiling decreases so dramatically. Risk during this period is dominated by RPV draindown events (60 85%), and LOOP (4-15%).
6
FlaalS:fety Review of the DAEC RF0H Plan A Side Safety Window and FuelShuf)le H, October 23 October 28 This time period represents a time when titel handling errors previously masked earlier by other loss of decay heat removal (DilR) events is now a larger contributor to the relative risk earlier.
Risk during this period is dominated by RPV draindown events (45 80%), inadvertent criticality (10 30%), and LOOP (10-75%).
A-Side Safety Window Continued,0ctoict 28-October 31 This period represents a time when fuel movement is not occurring, and systems are gradually l being restored on the A side. Thus, the risk of boiling in the vessel is at its lowest point until cavity draindown begins. As soon as draindown begins, inventory for bulk cooling of the irradiated fuel is decreased, and therefore, time to boll decreases. Risk during this period is initially (Oct. 30th) dominated by RPV draindown events,97%. Thereafter, risk is dominated by )
both RPV draindown events (50 55%) and SDC bypass events (20 25%).
AllSystems Available through Reactor Startup, October 31-November 8 Once the reactor cavity is drained, less inventory is available for bulk cooling of the irradiated fuel, and so time to boll is shorter. Risk is higher mainly as a function of time to-boil, even though all safety systems should be available. The LOOP LOCA test and Containment Test both represent high risk evolutions that can potentially challenge the plant safety systems, and thus their ability to respond to decay heat removal demands if necessary. However, in terms of absolute risk, the LOOP LOCA and Con.ainment tests do not add substantially to risk.
The reactor hydro window actually represents a relative risk decrease because at high pressure
(>l35 psi) several of the postulated accidents / initiating events are not plausible and thus are nc,t considered. This is an artificiality of the probabilistic models since they are oriented around coolant boiling, rather than core damage. Risk increases upon the hydro test completion to account for reactor startup. The transition period for the startup sequence is not explicitly modeled by ORAM. Risk during this period is generally dominated by SDC bypass events (90%). However, during the reactor hydro test risk is dominated by a loss of Division 2 AC bus (35%), small LOCA (23%), RPV drainc~own events (14%), and LOOP (11%).
Conclusion from PSSA Overall, the outage schedule planned for RF014 appears safe and reasonably minimizes risks within the constraints of resources and a shorter outage, while at the same time maximizing defense in-depth. The evaluation of a recent detailed schedule confirms this belief by illustrating a relatively low boiling frequency. The tesults of the PSSA evaluation are final (br. sed on information obtained on August 14,1996), and they are subject to change as the schedule changes prior to implementation.
7
. ~. s FinilSrfety Review of the DAEC RT0!4 Plan PART 3: Comparison of Outage Risk: February vs. August Schedules A graphical comparison was made between the outage ' .hedules that were obtained and i evaluated for the Preliminary Shutdown Risk Evaluation (Febmary) and the Final Shutdown Risk Evaluation (August). The details of the Preliminary Shutdown Risk Evaluation are described more fully in NO 96-0391.
Background and Cavents Each of the following two pages show the overall defense in-depth (colors) evaluation and probabilistic shutdown risk evaluation histogram for the February and the August schedules, respectively. The ORAM graphs rhown on the next page are from February's scheduling dates, but it takes into account implementation of the two recommendations of the Preliminary Shutdown Risk Report (No 96-0391) to eliminate two areas of red. Therefore, these graphs depict a slightly better picture than was communicated in the February report. The schedule from August takes into account the Noble Metals project, and the effect that has on overall outage resources.
An important r9te in comparing the histograms of outage risk profiles is that the ORAM software automatically adjusts the scales, such that the reader should exercise caution in a one-to-one comparison of the two histograms.
Finally, some minor modeling enhancements have been made to the DAEC ORAM models to provide a more accurate account of both defense in-depth colors and PSSA calcuk uns, based on feedback obtained from Outage Management. However, most of the effort in ducing overall risk (colors and PSSA) is due to modifications to the outage plan.
Summan' and Conclusion A generally consistent and continuing improvement has been observed throughout the outage planning and risk management process over the last six months. As a result, the August schedule when compared to the February schedule shows a marked improvement. Looking strictly at defense in-depth colors, you can see that a lot of orange in SDC and AC Power has been improved to yellow (and in some cases areas of green). Looking strictly at the risk histograms, 1 the average RCS boiling frequency has decreased from about 2.25E-6 events per hour to about 2.08E-6 events per hour. While this,in itself, may not seem significant, keep in mind that the majority of risk in either schedules is dominated by the effects of high decay heat early in the outage which is not directly controllable. The improvement in risk profile is the result of improvements in the outage schedule through careful consideration and coordination of resources
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( ATTACHMENT JL ~) .
PRA Today ,
Quarterly Newsletter for Probabilistic Risk Assessment Vol. 2, No. 3 3rd Quarter 1996 Shutdown Risk Management DAEC Refaeling Outage Thirteen represented a major j milestone for application of PRA technologies to As the nuclear industry continues to expand the use of outage management in three ways. First, the PSSA PRA for various activities, DAEC is amorg many of was performed (for the Drst time) by in house staff, front runner plants that are using their plant specine without significant assistance from outside contractors.
PRAs to help manage the risks associated with plant (This is important because the expertise level of the shutdowns. The NRC has given positive remarks to DAEC PRA group is conthually advancing, and thus those plants that are doing shutdown risk mar,agement, the dependence on outside support is decreasing.)
This is evidenced in our last two SALP reports, which Second, the PSSA for RFol3 was a refinement of the characterize our PRA and shutdown risk management methods developed for RF012, which made it a more process as strengths. The NRC is encouraging the rest comprehensive and complete model. Third, we used a of the nuclear industry to perform similar studies for Windows based software package called Outage R/sk their plant outages. In fect, the NRC is developing Assessment andManagement (ORAM) for the first new regulations (the Shutdawn Ru/c) to prescribe an time. ORAM sllows for faster tura around time and acceptable standard for risk management during low- communicates risk results more effectively, power and shutdown operations.
DAEC has already acnieved a status in the nuclear Implementation of ORAM for RF014 industry for being a leader in the application of PRA methods to refuel outages. This began with a broad in addition to calculating the risk profile, ORAM consideration of risks for RFoll, then the shows defense in depth evaluations for various critical development of a more comprehensive methodology shutdown safety functions (e.g., electrical power, for RF012, and finally a refinement of this shutdown cooling, fuel pool cooling, containment --
methodology further in RFol3 to address most every etc.) in terms of colors (green, yellow, orange, or red),
risk significant aspect of outage implementations. representing different " grades" of safety level. The colors depicted in ORAM are meant to simulate the colors for the various critical shutdown safety Probabilistic Shutdown Safety Assessment functions identified in Outage Management Guideline (PSSA) for RFOl3 Number 7 (OMG 7). Operators (Shift Technical Advisors) use this checklist to calculate the defense.
A formal PSSA can be a very time consuming and in-depth level for these safety functions throughout an extensive project, in the past, it has typically required outage. The colors calculated by ORAM try to one PRA engineer dedicated full time to the PSSA up account for more things than the checklist (e.g., decay to six months prior to the outage, Additional support heat level), therefore, there are differences between the has often been necessary in the form of consultants. two methods.
. This is because the PSSA model is a completely i separate model from that of the at power PRA. PSSAs Besides the ability to automate the Shutdown Safety require a signincant amount of effort to understand Assessment Checklist calculations of defense in depth outage configurations, activities, procedures, operator colors, this software tool can display Risk actions, postulated shutdown event scenarios, and Mmagement Guidelines (RMGs) texts that vary, RFO-specific planned system hammocks. The models depending on the specific plant conditions and system themselves are very complex to set up and can be availabilities. Additionally, plant staff now have a
- diflicult to manipulate in order to evaluate "w hat il" means for easy download of outage plans in a format questions, that is usable to the ORAM software, i
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As part of the ORAh!.RhtG models, the PRA group was the issue of the Gnal shutdown risk repon on odded a unique module to provide an explicit August 15th. Even so, we plan to keep on evaluating treatment of Gre risk issues into these models. (The schedules as they are updated to provide important NRC has identined Gre risk as an important issue in feeback into the process, the proposed Shutdown Ru/c.) DAEC was the Grst plant to attempt this task, and so we have been nominated to receive an liPRIInnovation A ward for Yuturc Work it. His module has enabled the Fire Protection Group to prioritize areas in w hich to pay closer attention Traditional probabilistic models for sbutdowns will be while performing plant area walkdowns and replaced by the ORAh! PSSA models. The ORAh!.
authorizing combustibles and " hot" work in the PSSA evaluation gives a risk profile and risk insights various compartments. The proactive efforts taken by consistent with those obtained from a full independent Outage hianagement, Operations, and the PRA group PSSA model(performed by a PRA staf0, yet has the regarding shutdown risk issues will reduce our Ocxibility to be used by operators w schedulers for exposure to increased requirements that rest.lt from the day to-day analyses. The PRA staff, however, will be NRC's new Shutdown Rule. available to provide technical support and guidance in the use of ORAhi, as needed, during outage The software also has a pertion dedicated to the more implementation.
traditional PSSA calculations of plant risk, including a risk pronle of the outage. This second portion of in the face of changing economic and regulatory ORAh! includes a probabilistic treatment of outage environment, we must continually look for ways to risks,just as the PSSA for past refuel outages did. improve the way we do business. Detter scheduling, This ponion of ORAh! was completed and tested in coordination of work, and efficient implementation of January of 1996. Program Engineering's PRA group outage activities go hand in hand with maintaining a completed the integrated ORAhi models (both safe operating and working environment. The PRA defense in depth and PSSA) and have used them to group is implementing better tools (in the form of evaluate outage schedules being developed for DAEC software) and automated means of obtaining and RF014 since February 1996. communicating risk information to non PRA staff.
We all must contribute toward achieving shorter A preliminary evaluation of the RFol4 plan was made outages by making these tools available to more staff in February in order to provide early feedback to without complete reliance on a PRA expert.
Outage hianagement regarding potential risk signi6 cant activities. This feedback also allowed schedulers to modify work activities to reduce the Information Contacts interactions between system unavailabliities in a manner that makes the plan safer and simultaneously For more information regarding shutdown risk manages resources effectively to reduce overall outage management, contact either Phil Carlotta (ext. 7760) in durstion. The PRA group has continued to evaluate Outage bienagement or Terry Lanc (ext. 7694) in the new schedules as they become availabis. The Risk and Performance Assessment Group.
culmination of the pre-outage risk assessment work
ATTAcRMENT 3 DAC 217 - 0830 - September 10,1996 MANAGEMENT REVIEW RFO 14 Week 3, Oct 21 - 27,1996 s AGENDA e Level 1/2 Schedule Summary e Critical Path Activities
- Overview of Detailed Schedule e Risk Review Week 3 Overview System Recoveries Begin! The 'B' Safety Systems are restored and the 'A' Safety Systems are tagged out during week 3. The Operations Dept, will be extremely challenged to clear 'A' Side tagouts (including ! A4), run all operability tests, and then hang the 'B' Side tagouts within approximately a 30-hour period. Reactor Water Cleanup is restored to service. Work fm' ishes on many Balance-of Plant Heat Exchangers. Fuel Shuffle #2 begins. The Outage is more than 1/2 over at the end of this week!
Distribution:
0.Vanh11ddlesworth Rob Anderson P. Bessette B. Hite K. Peveler K. Putnam J. Bjorseth bl. Brandt NRC D. Curtland B. Simmons B. hicCall hi. Smith K. Huber P. Carlotta T. Lanc '
A. Wolff C. Douglas O. Ellis R.Zook B. Voss R. hicGee B. hilck K. Kleinheinz ht. Teply J. Cantrell J. Nugent g -
RF014 GUTAGE SCHEUULE LEVEL 1/2
SUMMARY
ACTIVITIES DATED: 2S/05/06 OctSb C 3.scription CIVITY I SdeiL St Sched. Fi Dura 21 l22 l23 f24 l2h l2h }27 i2S ~
j i 1 '3' PmR EEKEN3 CN:DJ Z223tM Initi5th in!!!!15 12 E 2 LEU SYST WIN:UJ Z21tta %111715 % 182122 II3 M 3 1A4 tibi Y1T SWITUGEAR WCCW Ztitt1A4H nititin n it2312 53 i 4 *!* RHR/R6 !TST WIN OJ Z2It1H nitth24 %122328 n5 5 COTEN R'-2/5llC SYSTEM WIN:ZE Z2721H HitZ211 %122483 34 I l 5 6 ~3' E!'ER:;DCT PJi SYST WIN::CW Z224tH 5n111b24 %1titt5 174 7 3EGIN FUEL SHIEFLE42 MILEST3 E Z1141 361824Z2 nitI422 I l l l l 4 FEL SMTFL3 8Z N SE 43 3 SERVICE WER SYST WIN:lCW ZI!IIH 361I1417 fillin14 25 I C2f'LETE FUEL AFFLE*Z MILE 5TDE Z114Z S1875tt %1tritt t l l l .*C2PM 11 'A' M/M5W ST5T WCOW Z213tH Ih1121Z1 3611381I 1h1 11 'E3' Li". P't ?mR WEEKDC WINrJ Z277tH nil 24t1 hit 3121 thi l11 12 CGCEN5ER VACItt SUPPORT WC3J Z215tH nitll!! %123118 865 13 *W ETRGDCT PWR SYST WIN:al Z2t2tH 161824t3 htt3115 175 l l l l 14 G5W WORK 'J200J ZZIh8H 56181716 % 183115 35 15 GERIS IN5i HUJ W2GCu GERIS 1h111473 ibit3117 43 in 'W LRYWli CICLI'C WDC:M Z21tfH Mit14ti n121122 824 17 ECCS TUR3IT *)RIVD4 ST5 TIM WIN::::u Z225fH nilleti Hilli2 424 15 Tt.ACTUi StPRT SYST WCDJ Z273tH nittill n11 tits 158 . .
13 NUCLENi 3CILER SYSTEM WIN:DW Z221tH M111571 3hi11113 37T ZI LLET TESTI*G WIND [IJ Z!!41H nifitti n111114 445 21 LCW CT 3ASIN 1EVEL WGGJ "T3ASIN n111415 n1154I3 el3
( 22 DCENSATE L C:NIN50R WI'GCW Z187tH n181122 n1154th 561 l 21 3TiSATE L TEE 3 SYST WIN:lUW Z213tH B111122 niit4th ni l
24 LIT STEAnr.nTER !IllE WIN:DJ '227tH M1814tf H118514 in
, 25 IEM"dlL SAFETT ST7tDS WIN:iUW Z11IIH B1814f7 H118522 544 lb C::NTANOT YENT L SIFRT ST5T WC:3J Z2584 nil 1487 H113522 544
[ ZF MVAC ST5T WI'00J ZI!3fd M1814tf hill!!6 hit
?! .%IN L AUX TRltCFCRTH WIN 0W Z21',IH Hit!bli n118!I5 545 l
l 29 ELECTRICAL POWER ST5 TEM WINJ0W Z1%IH B111487 n118!!3 513 II GDERAL SUP?CRT ST5T WIN 33J Z"121H nititti n111!!1 ht3 21 ISI/EC Inspection Progras Wind.ew 212584 ht!!1tf %118323 IIIT l 6 l l l l l 1 !,
I M SCHEDULE +-) TL"BGI
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RF014 OUTAGE SCHEEULE -
j CRITICAL /NEAR CRITICAL ACTIVITY I l' DATEU: 89/26/9b 1 Oct9b l c w,;,u xnym I Sa.t St Sa.t n a 21 22 23 :
24 25 Zb 127 12B j 1 RFU14 OLIT!EE DURATI34 iTJT3ATS E181114 nintet 721 2 GERIS DGP PRll2 LOGOW GERIS Init1423 nit 3117 413
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!. 3 EMS / GERIS - ISI / MMIL S15421 n1815t! n113117 898 4 REPUCE SSPV EINMUS'S m ICU'S 81 C::S kVENH4 05:181414T n1819th nit 2421 nt
, 5 DNESSELMOi FUEL FCYE m nGCulJ Z219tH nititth 11132422 n1 h DMESSELMi[N FUEL PCYE M nOGW Z2191H nititen nit 2422 161 7 CNTADtDIT A3 SM'LDC STSID1 - 3 42EIII2 n182997 nitInt II
' 2 I v!LVE TEST M57ttli-2 nifful nitn17 tl 5 FINISH CD EMmCES 13nF niinif nitn17 I 3]
13 LPIM REPUCDfNT 154I n it n17 n 132216 24 13 M I
11 LP21 REPUCDENT IPCER YESSEL IITtt!U nitni! Hit 2215 14 11 M i 12 FEEMTER DiEEE V:LVE CPERAEILITT TEST thCri! Mit2287 nit 2257 1 12[
IITIFIN n 182215 n 182Ith 12 13 II-REPUCE TIP TUIDG 13 %
14 CLEm & DISP IS PIPDC DHTCEE YIStyt. E III EEERE IVYIII n 182222 nittn3 22 14 M 15 4tY DTIC EUS DECEED Yli WrLT FIFCT TEST 4229131 Hit!3tf H it2II7 1 15 [
n LEEKLT MTTERT DEIS 483t813 nitutT nignet 2 in {
if IIMY GENC TIP ffTER TU3E REPL I2TIPGtMF nil 23ti nit 2321 15 17 m u amre et DcP Ivnn nunn nuun 2 is t .I 11 C.Em L DISP CS P! PDC DHTCE2 YISUR. ! 8 DELEEES'IVYIII n 182322 n it2813 22 11 M : i ft SUPPORT GRIVE ASTTILY VII (NETSIS ERIN 3 nitH23 nit 24t3 it II 21 IRIVE ASSEF3LT VI3RATIM FNLTSIS 123tIETIE nit:323 nitIHT 43 Z1M 22 EFTlLOT TRITPJM SMPLDG (tc #NETSIS NS75433 16132487 1n132415 9 22 E 23 TSC TTH FILTER 1RIT NeiLY 13 HR CNTDCE GPER N52SIII n1124tf Hit 2413 12 23 M ^
24 PEFCRM TIlR TRnCE 2 EEN IETECTUR IN GCUP IIII!:S nit 2412 nit 24n II 24 E M SCHEDULE +---> TIMENOW e
RF014 OUTAGE SCHEDULE CRXTICAL/NEAR CRITICAL ACTIVITY DATED: 89/06/9b Oct9b C n.mi,% tcTmTT I Sea si Scu r; n== 21 22 : 23 24 25 i2b (27 12S 25 PERFCiU! TDR TEE 31 EACH DETEtim IM St3P IIIIt!T Hit!412 fnit2421 13 25 a PERFURM T2 TimCE DI EfC6 ::ETECT::R IN GR2P ilfIIII n187412 Silt 2421 it !bE 27 PERFCRM Tm TNICE De EFOI EETECTDR IN GR2P II53tn n157412 nit 2421 13 27E f5 VERITY D#ESSEL ACTIVITIE3 CFPLETE 1778 InitI429 Inis2428 3 23l D SlAP FR31 T TO T SHUTDel C2LDG Itt4!H3F Hil24Z1 1n182421 2 21l 38 IEEIN FUEL SiUTLE*! L FRICTIM TESTDC M Z11483 Hit!422 n it2422 I Isb STMT FLE REL30 31 FINISH D#ESSD/Of FUEL FCYE E ZZ13tF nit!422 InitI472 3 31l 32 55.It CR3 WDERIC 500K Z55NF nitF422 nit 2422 8 32l 33 71.31 fEV2PI FONITURDG HDDK ZTit1F D 11Z422 n it2422 I I3l 34 ESTAILISH YESSEL QARITT 1682A Hitt4ZZ n1875tf 12 34 E 15 FUEL StFFLE82/FRICTI24 TESTDC DGE Z11483 n it!422 5n183898 111 E n saa FLEL SHUFFLE r2 see Int 3 1615I518 Init2NT 78 3e 17 REFUEL PLATTURM MILY IN5FECTIDI N5 tift 1RL 5187511 Init!!th it 37 33 LEEILY ffMML SCiMrt FUCTI34L 41At113 nit!Tti nit!Tt7 1 IIl 31 LI:lUID RADI45TE SYSTEM LEM!CE DEPEITIM lI5M4 H itIT2T InitITt7 1 11l 48 :IESEL URIVEN FIRE P9 L FUEL DIL SLPPLY VERI N5133H13 n 1 bitin 5n122717 2 atl 41 TUR3 CNTitDL YLY EDC RPT LOGIC L RPS IN5T FUC 41 Aft 3 n itI!si Init net 2 41l 47 TI ST P VLY CLU"JtE RPS & RPT FUC TEST
. 41A818 nitINT nit 2MB 2 82 {
41 C2PLU E FUEL SH:FFLE*! ?!ILEST3E Z1142 n152!M . nit!!n a de COMPLE 44 C:RE VERIFICATI m ibl4 In15Het nit!!15 8 44 E 45 YrtVE TEST PerHti-3 n it7 tin 1n182!17 2 45 [
66 FRICTI24 TESTDC 0 6 551313 int 3A HitItin $nitIH7 48 46 4T MU..nN TESTDG IN555f t13 Int 33 niinin Snit 3H 7 43 47 45 C3dTR3. R3 C2PLDC INTE5RITT 43A993 niti!16 H183NT 43 4!
SCHEUllLE t---> TIFBG -
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2 Overview of Detailed Schedule for October 21,1996 thru October 27,1996 October 21,1996 (Monday) 0700 - Tagout Common RilR Shutdown Cooling Suction 1000 Clear Tage'its on 1D20, ID21, ID23 $
1300 - Clear Tags on 'B' Core Spray 1900 - Clear 'A' RPS Tagout i 2000 - Clear 'B' RHRSW Tagout I
- Clear RWCU Tagout 2200 . Clear I A4 Tagout 2300 - Clear 'B' RHR Tagout
- Run 'B' RHRSW Op Test 2400 Clear 'B' EDG Tagout
- Hang 'B' RPS Tagout
- Run 'B' RWS Op Test
< October 22,1996 ,
0100 - P m 'B' ESW Op Test
- Run 'B' Core Spray Op Test
- Perform 'B' EDO Maintenance Run 0200 - Restore RWCU to Service 0300 - Run 'B' RHR Op Test 0500 - Run 'B' EDO Op Test 0700 - SBLC ManualInjection STP 0900 - Tagout 'A' RWS
- Tagout 'A' RHRSW
- Tagout 'A' RHR ,
- Tagout 'A' Core Spray 1300 - Clerr 'A' RWS Tagout ,
- Drafn 'A' RHR /
- Tagout 'A' ESW
-Tagout SBLC 1700 s Run 'A' RWS Op Test
?100 - Clear 'A' RHRSW Tagout 2300 - 125vde Div. I Battery Discharge Test O
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l October 23,1996 0600 'A' ESW retumed to service 3
0700 Run 'A' RHRSW Op Test 0800 - ECP1559 work in IDI1 begins j i
1500 ECP1559 work in ID13 begins ,
- ID14 Restored !
1700 - Clear RCIC Water Side Tagout l October 24,1996 l 0700 - Clear tags on Common RHR Shutdown Cooling Suction 1300 - Start 'B' Shutdown Cooling-1600 - Clear 'B' RPS Tagout October 25,19F {
0300 - Start Closing some Main Condenser Waterboxes 1000 - Begin Fuel Shuffle #2 (70 hours8.101852e-4 days <br />0.0194 hours <br />1.157407e-4 weeks <br />2.6635e-5 months <br />) i 1600 - Clear Tags on JX105C ?
October 26,1996
- 0200 - Shielding removal from the Drywell begins--
October 27,1996 1300 - B' Feed Pump Reassembly Completed !
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RFO 14: Outage Risk Defense-in-Depth for Week 43
= Satody Function Status
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ff 23 25~ 27 -29 Shutdown Cooling Fuel Poof CooIing Ill! M il B E - E M I E-i n ilff{% M E!il!3fHs@mq1M Inventory Control (((( M M{ " - =" M rYINENilllEEE NIH OIll1 AC Power Control """" RIN i Reactivity Control }itl&HlillQ9'EMBHMN Fael Shuffle #2 ISENI Containrnent Control l$EFifMf] >
SDCFire Vulnetability 4 h- .(
Week'43: October 21 - October 27,1996 Risk Management:
(1) SDC is orange (Oct. 22-23) while common SDC suction line is inoperable. The FPC system is the only system. by itself, capable of decay heat removal.
(2) AC Power is still orange (Oct. 21st) due to B-side electrical systems work windows and the B-side EDG unavailability.
(3) Transition from B-side Safety Window to A-side Safety Window on October 24th.
(4) Time-to-Boil is greater than 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> throughout the week.
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J ATIAc4(dEhfrRFdTtolim e Meetings 4
Individual shops and groups will do their own turnover between shifts. The Work Control Center util not be supporting work sign-on from 0630 to 0700 or 1830 to 1900 to allow for operations shift turnover.
Shift Status Update 0530 & 1730 Daily 20 inin Ohi Conf. room (DAC 117) by imitation only.
Required Attendees: Shift Team Leader (1 & 0) (i = Incoming, O = Out going) ,
hiaint. Supenntendent (1 & O)
Electrical Supenisor (0) blechanical Supenisor (0)
I & C Supenisor (0)
Outage Communicator 1
0 Risk Management rniew !
O Resiew work progress, problems and coordination issues.
O Issues for turnover to the next shift 4 WCC Turnover 0600 & 1100 Daily 20 min. -TSC byimitation only Required Attendees: Shift Team Leader (1) Outage Support Supenisor (1) hiaint. Superintendents (I) Radiation Protection Supenisor (1)
Operations hianagers (I) Engineering Support Supenisor (!)
Outage hhnagement (I) Closecut Team Supenisor (!)
Maintenance TOSS (I) Outage Communicator FIN Team Leader TSIP Advisor PRA Eng;ntu, O Risk Management review - PRA pr'esentaibn 0 Schedule Status O Major work or plant evolution's in progress 0 Open issues that need near term resolution or hand-off from shift to shift
& Plan Of the Day / Night -0730 & 1930 - Daily - 15 min. Small conference room f0 [.,g#
Required Attendees: Key personnel not involved in the WCC Turnover meeting. / )* g(
- 0 ,
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O Risk Management review I PRA fcsenS4/Dn I LV O Schedule status and work turnover from previous shift.
O Major evolution's in progress g ,, ,
O Issues for turnover to the next shift and Look Ahead for tomorrow. *7 4
LoIk Ahead - 1000 & 2000 - Monday, Wednesday, Friday - 30 mirl DAC 217 Required Attendees: Maintenance Supenisors Representatives from all other departments .
O Resiew the following three days (Big Picture) of the outage schedule.
O Identify any issues or challenges to the schedule.
d'l R: port 7:00 PM DAY SHIFT TURNOVER Tuesday Evening, October 15,1996 Hlahllahts from Day Shift:
- 1. Startup Transformer work - Refilled with oil. System Protection started Doble Test to check leakage current and verify insulation okay. When Doble test is complete, electricians will finish reassembly. Look ahead Start Main Transformer work this weekend, Start 1 A4 Bus work Wednesday.
- 2. Refuel Floor -
Dayshift Moving cattle chute into position, establishing FME Zone around cavity and pools. RPV Head detensioned and ready to move.
Nightshift Move RPV Head at start of shift, then move steam dryer, install Main Steam Line Plugs (start -10PM, finish ~1 AM). After MSL Pluos installed OPS & Refuel Floor nood tg goordinate to raise RPV level Teply recommends raising level to about 6" below the RPV flanan,,
this is needed to cool the flange and vesselin support of flange & stud UTs and GERIS inspections. Vessel metal temperature must be < 120 'F. (What systems will be used for injection?, How long will it take to raise level?) After temp & level are catablished, start UTs.
- 3. Circ Water Pits dralned, hydrolasing in progress.
- 4. *B" River Water Supply pit drained & cleaning in preparations for zebra mussel coating installation. During a cleaning the screen wash pump started and injected water into pit. Plant Engineering (T. Barada) prepared a Temporary Modification to Install a sump pump in pit to keep it drained, this has been INSTALLED.
- 5. "A: RFP - Machining shaft & shaft nut for thrust bearing tonight, Non-Conformance AR being evaluated by Maintenance and Engineering. Need J. Johnson to orovide final dimensions for machining.
Plant ODerations: RPV level at 235",1B2 cross tied to 181,1B6 cross tied to 1B5, RPV '
t;mperature belng kept 80-100 8F, shifted shutdown cooling to B RHR Loop. It has been a challenge to coordinate LP Ol inject STP 46G034 CY and transfer of Shutdown Cooling (tagouts & lineups) B LPCI check valve response being evaluated.
PRIORITIE.3 FOR NIGHTSHIFT
- 2. Complete GSW tagout, Start GSW Window Work - Recirc Cooler & Iso Bus Duct Cooler Pipe replacement , Mech Shop j
- 3. Complete DW Readiness, Finish 1JX105C Scaffold in Drywell.
- 4. Complete STP 46G034 CY, LPCI Check Valve Test, then swap SDC to "A" RHR Loop and secure RWCU for LLRTs.
S. Aux Boiler start logic, Aux Boller will not start, FIN Team to turnover to nights. Lead -T. Vine m
- ,.\
Day Shift Notes:
LLRT TIP ball valves, MO 4891B and V 43 441 completed SAT, tonight start DW Cooler Work - Feedwater Check Valve (drywell) and RWCU (dtywell & HX room) LLRTs.
Need night shift to build a berm wall cround acid tank, not on schedule, civil Main Generator Work Project on-shop to support. schedule, tonight will continue Generator Dehydration with HIT skid, should Repair options still being evaluated, complete by end of night shift, A CMAR is being prepared to cutout a section of IV CC 1 A cooler outlet piping Mechanical Maintenance -
which will be sent to a lab for analysis.
FW Heater Cleaning / Inspections started Flush "A" DW Cooling Loop tonight if OPS support available. If flush is performed, (1 E-3A/B).
CHECK for leaks in drywell WW piping.
Stator Cooling Pump Repairs -
Disassembly complete, replacemt nt parts Consideration still being given to installing Bolzona on inlet / outlet piping connection to correc ( ' haft as 0ts}
9 nah w Al g 9e use to get coolers. parts and fix BOM problems.
Leads / Contacts: Dayshift M. Huting, Nights K. Schneider Fuel Move Readiness Review - -
Wednesday, Days 1300 in DAC Room Feedwater Enhancements The hold f was removed on FW control STPs Work Priorities are as follows:
crihancements (ECP 1566 controller upgrade, EMAs for FWRV work). Issues 1. 46G034-CY, LPCI Inject Ck Valve Test related to system stability have been 2, 42G003, ATWS ARis, may need I&C resolved. Engineering will continue support if problems occur, cvaluating open issues related to 3. 42s008 PCIS Group 7, after RBCCW cal!bration of controllers, etc. LLRTs completed, remove B WW Pump from service.
START WORK TONIGHT. l&C will be 4. 42A030-CY, SBGT Actuation, removing instrumentation at Panel 1018. reschedule due to tagout conflicts.
- 5. 41 A004-SD, IRM Trip Test, started
~
DRYWELL WORK - DW Readiness 6. 45J001 Will be done prior to Preparation finishes tonlaht Started LOOP /LOCA 1JX105C scaffolding - continue on nights.
Shielding completed on 757' level, Safety - Several injuries reported: ISI Penetrations SW9 open - will open SW7 supervisor foll in the drywell over the tonight for ISI. Will remove outer blocks weekend and bruised legs and hips,1 for SW3/4/5/6 tonight. Remove Recirc wasp sting,1 craft injured by shackle that Discharge Nozzle insulation tonight, separated from rigging and fell.
GERIS Inspections have started and will continue tonight in SW7 penetration. Good Catch - Operators installing tagouts for "A" Recire work identified that electrical HPCI Check Valve Removal- Check portion of tagout was written for tagout of valve removed, weld preos continuina for the "B" side. Problem was identified and new pipe installation, resolved before work released.
- 4,*
QBAM Risk _ AssessmenLSumniary
%esdag Date: OCf IS.lC4b Time: _l700 NE
' a.m @ Risk Analyst: b ___
6 Plant Evolutions And Milestones:
1 hoval of RPV head, ReGel mode A. SDC ln service. '
- 3. Rivce U.b4c/ 6 ard Gstd 005 Time to Boll (RPV/ Cavity): 3 hours safety Function Defense in Depth:I Wqh decay heat i Qd(Bleed not Cafudt ([ f(MN3 Shutdown Cooling:
GY@Rhgdeca; heaf if SDC is (ost. .
f Recirc urdualldW. dut to CM LO0d f 'M #
Fuel Pool Cooling: @YOR' .
Inventory Control: HOR h AC Power Control: G@O R [54arkp %nS[nrmer DOS o/
Reactivity Control: @YOR f Containment Control: G hO R Fire Vulnerability: Gy@R 'b' RWS i,5 unwaila We,
- IProtected Systems: #
Y d
Y ca e.s & src.
g DecayHeatnemoval: % (cops oP RRR, RHRsu), Esu.)
Vessel Inventory Control: 'N CRP , 'A' and '8' Core, Qrty, ODrdells, Service.W&
T j Electrical Power: both E%s, Slway +vansbrmer, swHchyard Reactivity Control: RPS, }kdron moni4ofinj Containment Control: secondorf conhinment iS reguireq $< (Mires Otdge.
Contingencies:
Risk issues and Insights-is h/f 6 O 8rs/ several I. Loss spgii, gst stner@ilHy. Rick
- a. Decay 6 a4 Ts $13 h io"f%. Incendog is Iouh w w % borl is Short.
. gns .
3 @ SDC CVSN'0 5
'W Wb y, Star -Intns[ormu- Is down, so EA3s aM S/8 fans [ornieA. w,
/m t /dd.
._ _ _ . . _ _ _ . _ _ . _ . _ _ _ . - . . . _ _ . _ . , .. - _ _ - _ _ .. . ~ . _ _ _ . . _ _ _ _ _ _ _ _ . - _ . . _ _ . _ _ . . < - .
N- . ;
Date 10/18/96 11:29 DUANE ARNOLD - Report Page: 001
~'l OUTAGE RISK ASSESSMENT AND MANAGEMENT Outage: RFO14 : REFUEUNG OUTAGE : RCS Boihng Risk Profile Model RFC14 : Wcetung Model of DAEC RF014 .
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Date: 10/18/96 11:27 DUANE ARNOLD ~4eport page: 001 ,
OUTAGE RISK ASSESSMENT AND MAN.4GEMENT Outage: RF014 : REFUELING OUTAGE Safety Fonction Status Report Itodel: RF014:Vr
- 7VW of DAEC RFO14 ,
2nStd on o.duqe schedufe fx oc+ober 15,1976 Oct Nov 11 21 31 10 Shutdown Cooling
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CYCLE 14 P O c"t J?
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- Uj@ In Our perform ance. Da3s or coniinuous Operation Since 6/6/95 RFO 14 New hecord 4th 1)av 5 Longest in World for HWRs y/ // ,ax p %- - Nwm .
w: x 493 days
/// NNN 4,000,000 Man flours Without a Lost Time injurv QWN
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// / '%A N NN Days Sinco a Lost Timo Accident y on Oct 24,1993 10/15/96 1086 issue 877 Nightshift Turnover Plant challengesivutage Kisk Stanup Transformer - Started vacuum pump during night shin. Found a leak on the oil pump. Replaced an Last evening we reached Cold Shutdown (less than 212 degrees o-ring and restarted the vacuum pump. The vacuum test in the vessel), after completing the Noble Metals project. The should be completed around 8:00. The oil fill will take startup transformer is being worked, and the non-essential buses another 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> followed by a Doble test. are being powered via backfeeds through the main and auxiliary transformers. Systems down today will include B-side River Mechanical Maintenance -Continue Installation of the Water Supply, the B side Standby Gas Treatment System, FW lleater hoists. A RFP work in progress continued. GSW, RWCU for LLRTs and many other balance of plant Removed the one stuck nut, which damaged the stud systems.
shan. Replacement parts are available.
PROTECTED SYSTEMS e LLRT - Tests on CV3704, CV3705, CV3728, CV3729, Decay Heat Removal: Both trains of RHR, RHRSW, and ESW CV4300, CV4301, CV4357, CV4309, V-17-52, V 17 Inventory Control: "A" CRD pump, both trains of Core Spray, J were completed on night shift. All valves passed. and Condensate Service Water MO-4841 A and B test is still continuing. Electrical Power: Both Emergency Diesel Generators, the Standby Transformer, and the switchyard Temp Power ! Lighting Mobilized Drywell temporary (while the startup transformer is down)
Reactivity Control: Reactor Protection System, Neutron lighting and power, waiting for Drywell Equipment hatch Monitoring Systems to be openei Contaimnent Control: Secondary containment will be maintained for the entire outage.
I&C STPs scheduled tonight - need coordination & check that all prerequisites met: 41 A004, IRM Trip not OUTAGE RISK started. 42A030 B Train on da) shift and the A Train rescheduled for SBGT Actuation. 41 A006.1, SDV H For the first several days after shutdown decay heat is relatively Level Tri*, Test is in progress, high. Critical to decay heat remoyal is one or both trains of Shutdown Cooling (RHR and its supports). Other balance of Rod Sea..c Matrix Connectors repaired, identified plant systems, such as Condensate Service Water and a problem with 4 corner select switch connectors to be a rec::culation pump, can also be important. The majority of risk for an omage is during the first several days after shutdown. Our pin positioned incorrectly - repairs complete. Backlight '
problems (previousiv existed) fixed, start operability & greatest con' butor to plant risk during this time are loss of SDC events. Stop, Check, and Think before proceding with any job.
acceptance testing completed satisf actorily. Flood up Be aware of which systems are identified r protected. Lets have level instrument hooked up and was calibrated.
a safe and productive outage, lb2$PN "@ P E*>
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THE BACK PAGE l Safely Speaking Nightshift Turnoser (continued)
Ladies and Gentlemen: We haw sustained a doctor's case DRYWELL WORK - DW Readiness Preparation continued injury for refuel outage 14. The injury was a laceration which tonight. htajor activities included; downcomer covers required four sutures to close. The incident occurred w hile installed, drywell shiciding installed on the D riser and 775' using a knife to cut a tie-wrap ' d an extension cord. The Shutdown cooling line, opening DW Equipment llatch.
preferred method f removi g tic wraps is with a set of cutters. Utility kus and grsonal knives are not the correct Refuel Floor Work Started disassembly tonight! Drywcll tool fcw this job. Let's :,arn from this incident; increase our head removed at 0230. Around 2130 an air hose in the reactor awareness aad keep moving forward SAFELY 1 cavity disconnected and blew dust around, contaminating four craft personnel and causing the Refuel Floor to go airborne. A DEBRIS PREVENTION Fact Finding meeting was conducted, and all hoses were checked before work resumed. Work stopped on the Refuel Question: Flcor for around 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. Decon of the RxBig 855' Which :ould cause more damage to plant equipment, a 1/4" performed from 3-5 Ahi. Commensed removing the adjustabk wrench or a 1/4" x 1/8" metal shaving? insulation head.
Answer: Snubber Going well, Heater Bay STP done SAT.
Both can have a detrimental effects on plant equipment.
Operations -
You might wonder how a small metal shavm, g can cause a GSW drained down.
failure to plant equipment. B" side S/D Panel STP completed, Pumpdown of"B" River Water Supply.
A metal shaving 1/4" x 1/8" can become lodged inside a fuel Pump Down Cite Water Pit, bundle and as the water 9ows through the bundle, the metal I&C h help place ESW Pit level Fluke in front panel area.
shaving can start to vibrate and erode through the fuel pin and F re system header removed from service FPIR in pk :e.
cause a fuel failure. -
Scaffolding. Scaffolding for the exterior of the conc'enser k The origin of the metal shaving can be from any activity on waterboxes and the scaffolding for hiO 2239 and 310 3401 in
,' a system which interfaces with the reactor vessel. the steam tunnel were completed ton!gt.t. One of the scaffolds ir 6he torus was bending under l'.s own weight with What can YOU do to help prevent equipment failure? no one on it. The scaffold has been tagged red for do not use.
- 1) hiaintain good housekeeping at the work site. New Revision to PWR Form Revision 6 to the PWR form is now available on NGForms,
- 2) Be aware that small debris can have a significant effect on If you have a stash of the old revision, please discard them.
plant operation. Cleanliness control is very important.
focus on....
- 3) Cneck the equipment you wili be using prior to e'.tering m,;aintaining a questigning att eude regardi9 P lant an FhtE zone to ensure that the nuts / screws /etc. are D.stened .etivities, exp,et the unexpected.
.tdequately. Also perform a post inypection of the equipment . Constantly seek . improve performance by tearning you used to ensure ncthing is missmg.
from the experiences of yourself and others.
- 4) If something gets dropped, not only in the reactor vessel,
- Alwa55 Perform your duties with high personal but in any area (condenser, valve body, steam line, etc.), let standards of honesty, integrity. and ethics.
someone know immediately. The extra time taken now will
- Always remember that pubtle, personnet, and plant help prevent problems later on. safety outweigh att other considerations in reaching decionons.
If you have any questions or comments, please let me know . ,
'h'"-
Thanks.
Bob Vita x7328
- Alwass
- oF any work ee activity that ma5 je0Pardite Reactor Engineering. plant or personnet safety.
(
- Cevelop a sense of pride and ownership in your work. j
4 =.
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ATTAckms0T 9 l
Attachment:
Shutdown Decay Heat The attached three graphs are an overview of our initial data collection to validate our best ,
l estimate of decay heat at DAEC. The data is from the Plant Process Computer (PPC) via j the PI( Plant Information) sonware.
I The first graph, labeled " Decay Heat Early in RFO 14," covers the first days following reactor shutdown. During this period, decay heat was being removed by four primary 1- means: Main Condenser; RHR in Shutdown Cooling (SDC) mode; RWCU; and Losses to j ambient by the RPV which was being maintained at a high tempeinture for noble metal injection. The line labeled "Qdot_DH_ Tot" is the sum of data from all four of these j modes of decay heat removal. The dashed line labeled "Qdot rhr" is the data for RHR in l SDC which is the major, but not only, mode after the first few hours. The curve labeled
" Calculated Decay Heat" is our best estimate of decay heat generation but is not our
, licensing basis. During a period of about 4 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after reactor shutdown, changes in i the RHR lineup were made. This caused a reduction in heat removal for about two hours followed by enhanced heat removal from the temporarily elevated temperatures.
]
The second graph, labeled " Heat Rejection - SDC," compares our best estimate of decay heat gencation with heat removal by SDC for RFO 14 up to the present. At about the three day point, the Main Condenser had been secured, RWCU was secured, and the final cooldown was commenced. The jump in heat removal by SDC on the afternoon of l 10/14/96 reflects the removal of stored heat from the reactor vessel and internals on top of the decay heat generated by the irradiated fuel. On the order of 20 MWH of energy is i stored in the reactor vessel and internals. The dip in SDC heat removal around noon on 10/17/96 is due to the addition of relatively cold water during floodup.
I The third graph of" Vessel Temperatures" shows the coolant and vessel metal temperatures during the extended cocidown phase at the beginning of RFO 14.
We are continuing to track shutdown decay heat. Our preliminary conclusion is that our calcu. tion. of shutdown decay heat is accurate and matches measured data very well. This serves as a good basis for use in our risk calculations.
o.
r 2-53 PM,10/17/96 .
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i Decay Heat Early in RFO 14 '
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Calculated Decay Heat
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time ,
t Risk Performance Assessment Group DAEC i
2:47 PM.10/17/96 'j.
Heat Rejection - SDC 18 16 -~
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j l + Odot_rhr_ Tot h Calculated Decay Heg 8 - 1 "
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10/11/96 12.00 10/12/96 12:00 10/13/96 12:00 10/14/96 12:00 10/15/96 12:00 10/16/96 12.00 10/17/96 12.00 10/18/96 12:00 10/19/96 12:00 time Risk Performance Assessment Group DAEC
, , . . 2,. . . . ,ni.
2:54 PM,10/17/96 ,-
e VeselTemperatures 550 f I X l 500 ----- - - - - - . - - . - ,
%X NX 450 -- X x_ _ _ - . _ _
400 -
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350 ./h REACTOR BOTTOM HEAD l !
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7 50 10/11/96 0 00 10/12/96 0:00 10/13/96 0.00 10/14/96 0.00 10/15/96 0.00 10/1f.'M 0:00 10/17/96 0.00 10/18/96 0.00 time Risk Performance #ssessment Group DAEC l
_