ML20113F744
| ML20113F744 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 09/23/1996 |
| From: | Peveler K IES UTILITIES INC., (FORMERLY IOWA ELECTRIC LIGHT |
| To: | NRC (Affiliation Not Assigned), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20113F748 | List: |
| References | |
| NEP-96-0063, NEP-96-63, TAC-M93692, NUDOCS 9609250308 | |
| Download: ML20113F744 (33) | |
Text
-
IES Utilities Inc.
200 Fest Street SE.
PO. dox 351 Cedar Rapids, IA 52406-0351 Telephone 319 398 4411 UTILITIES
}
September 23,1996 NEP-96-0063 i
Mr. William T Russell, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station PI-37 Washington, DC 20555-0001
Subject:
Duane Amold Energy Center Docket No: 50-331 Op. License No: DPR-49 Proposed Revision to Emergency Action Levels
Reference:
- 1) Letter from L. Heckert (lES) to W. Russell (NRC) dated September 15,1995, NEP-95-0184
- 2) Letter from G. Kelly (NRR) to L. Liu (IES) dated December 6,1995 Duane Arnold Energy Center-Request for Additional Information on EAL Revision To NUMARC/NESP-007 Methodology (M93692) i File:
A-221 t
Dear Mr. Russell:
In Reference 1, IES Utilities Inc. submitted a Duane Amold Energy Center (DAEC) proposed revision to the Emergency Action Levels for NRC review and approval. This submittal incorporates the guidelines contained in NUMARC/NESP-007," Methodology j
i for Development of Emergency Action Levels (EALs)".
/
j In Reference 2, your Staff requested additional information regarding the DAEC's I
proposed revision. This additional information, along with a revised version of DAEC's proposed revision to Emergency Action Levels, is included in the attachment.
/N.
M00M 9609250308 960923 i
PDR ADOCK 05000331 F
PDR An IES Industnes Company
)
e 9
l Mr. William T. Russell j
NEP-96-0063 September 23,1996 Page 2 Should you have any questions regarding this matter, please contact Larry Heckert at i
319-851-7016 or my office at 319-851-7801.
l i
Sincerely,
- Kb Kenneth E. Peveler Manager, Licensing and Emergency Planning i
l KP/kd Attachment l
l cc:
G. Kelly (NRC-NRR)
A. B. Beach (Region III)
NRC Resident Office l
DOCU l
REOUEST FOR ADDITIONAL INFORMATION REGARDING DUANE ARNOLD ENERGY CENTER EAL REVISION TO NUMARC/NESP-007 METHODOLOGY l
The NRC has completed its initial review of the proposed Emergency Action Levels (EALs) contained in the September 15,1995, Duane Arnold Energy Center submittal.
The submittal consisted of the proposed EAL procedure, the Duane Arnold EAL Technical Basis Document, letters of agreement from State and local authorities, and copies of applicable Emergency Operating and Abnormal Operating procedures. The l
EAL procedure contained the EAL stateinents, the corresponding emergency classifications, a unique designator number for each EAL, the plant Operating Condition Applicability, and any tables or other data necessary for interpretation of the EAL. The l
Technical Basis Document gave further details on the EAL, provided justifcation for any l
deviations from the NUMARC example EALs and cited specific Duane Arnold procedure numbers and other related references.
The proposed EALs were reviewed against the guidance in NUMARC/NESP-007,
" Methodology for Development of Emergency Action Levels," Revision 2. This l
document has been endorsed by the NRC in Regulatory Guide 1.101," Emergency l
Planning and Preparedness for Nuclear Power Reactors," Revision 3, as an alternative means by which licensees can meet the requirements in 10 CFR 50.47 (b) (4) and Appendix E to 10 CFR Part 50. Since the staff has previously endorsed the guidance in NUMARC/NESP-007, the review focused on those EALs that deviated from the guidance and those EALs that required the development of site-specific thresholds. As a result of the initial review, a number of EALs were identified which required additional l
information in order to determine whether the EALs conform to NUMARC/NESP-007.
Please provide this additional information as discussed below.
GENERAL I
Issued No.1 The Duane Arnold EAL scheme deviated from the NUMARC methodology by not grouping EALs under initiating conditions (ICs). The Duane Arnold EAL basis document did group the EALs under ICs; however, this arrangement was not maintained in the emergency imp'ementing procedure used for classifying the emergency. The grouping of EALs under the ICs to which the EALs correspond allows the person classifying (and the people being notified of the classification) to more clearly understand the plant condition of concern.
1 l
O l
l IES Utilities Response The NUMARC IC's are paraphrased in the left hand column of the DAEC table, in the form of Event Types. This allows the Operations Shift Supervisor / Emergency Coordinator to quickly focus on only those Emergency Action Levels (EALs) that pertain to current plant conditions.
The DAEC EAL scheme is consistent with current Operation's Department practices and training. The DAEC currently identifies EAL's (Emergency Action Level's) in a table format. Consideration was given to adding the NUMARC IC's (Initiating Conditions) to the DAEC EAL table. It is the choice of the Operation's Department to identify only the EAL's on the table and not the associated IC's text. The NUMARC IC's will be listed in Emergency Plan Implementing Procedure (EPIP) 1.1, " Determination of Emergency Action Levels", upon NRC approval of the DAEC NUMARC basis document.
Additional information that may not directly link plant specific indications to plant specific EAL's could add confusion and delay the decision making process. The DAEC chose to add a fifth column that allows the operators to quickly identify the specific area of concern (much like IC's). The Operation Department staffis trained and familiar with this layout. This layout allows the Operators to quickly identify plant conditions and i
associate those plant conditions with the NUMARC EAL thresholds, thus avoiding the use of two or more documents.
l NUMARC Recognition Category A l
Abnormal Rad Levels / Radiological Effluent l
\\
t Issue No. 2 NUMARC Initiating Condition (IC) AUl states:
AU1 Any m1 planned Release ofGaseous or Liquid Radioactivity to the Environment that Exceeds Two Times the Radiological Technicas Specificationsfor 60 Minutes or Longer.
NUMARC EALs associated with this IC include:
1.
A valid reading on one or more ofthefollowing monitors that exceeds the "value shown" (site specific monitors) indicates that the release may have exceeded the above criterion and indicates the need to assess the release with (site specific procedure):
(site-specific list) 2.
Confirmed sample analysesfor gaseous or liquid releases indicates concentrations or release rates with a release duration of 60 minutes or longer in excess oftwo times (site-specific technical l
specifications).
2 l
o l
A.
An EAL corresponding the NUMARC Example EAL 2 was not provided. No l
justification for this deviation was provided. (This comment also applies to the corresponding Duane Arnold Alert level EAL AA1.)
l B.
In the Duane Amold basis document for this EAL it is stated that:
The Low Level Radwaste Processing and Storage Facility (LLRPSF) is not considered as an accident release point since the radiation monitor automatically trips the building exhaust at the Technical Specification instantaneous release limit thus terminating the release..
l The NUMARC basis states that this IC " represents an uncontrolled situation and hence, a potential degradation in the level of safety." In formulating the EALs for this IC, it should not be presumed that safety systems will operate as designed. In fact it is the misoperation of this equipment which will cause the IC to be met.
Therefore, the Duane Arnold EAL scheme should include EALs for the monitored release paths. (This comment also applies to the corresponding Duane Arnold Alert level EAL AAl.)
IES Utilities Resnonse EAL's have been added to meet the NUMARC condition of concern. The DAEC EAL's read " Confirmed sample analyses for gaseous or liquid releases indicates concentrations in excess of 2 times ODAM limits for greater than 60 minutes" for l
AUl and " Confirmed sample analyses for gaseous or liquid releases indicates concentrations in excess of 200 times ODAM limits for greater than 15 minutes" for AAl.
In order to meet the NUMARC condition of concern for issue 2 B, EAL's have l
been added which read " Valid LLRSPF (Kaman) rad monitor reading above 9 E-4 pCi/cc for more than 60 minutes" for AUl and " Valid LLRSPF (Kaman) rad monitor reading above 9 E-2 pCi/cc for more than 15 minutes" for AAl.
Issue No. 3 NUMARC Initiating Condition (IC) AAl states:
AA1 Any unplanned Release ofGaseous or Liquid Radioactivity to the Environment that Exceeds 200 Times the Radiological Technical Specificationsfor 15 Minutes or Longer.
A NUMARC EAL associated with this IC is:
l 3.
A valid reading on perimeter radiation monitoring system greater than 10.0 mR/hr sustainedfor 15 minutes or longer.
4 1
i 3
The equivalent Duane Arnold EAL is:
l Validfieldsurvey reading outside the site boundary above 10 mR/hr.
(Dose assessment is NOTavailable.)
A.
The addition of the condition " dose assessment NOT available" is not appropriate because exceeding the survey results, in and ofitself, is indicative of a loss of control of radioactive material which meets the IC. (This comment also applies to Duane Arnold EALs ASI and AGl.)
B.
The Duane Arnold EAL did not include the condition " sustained for 15 minutes or l
longer." Nojustification was provided for this deviation. (This same comment also applies to Duane Arnold EALs ASI and AGl.)
l l
IES Utilities Resnonse The phrase " dose assessment NOT available" has been removed and the l
phrase " sustained for 15 minutes or longer" has been added to the EAL's under IC's AAl, AS1, and AGl.
l Issue No. 4 NUMARC IC AA2 states:
AA2 Major Damage to Irradiated Fuel or Loss of Water Level that Has or Will l
Result in the Uncovering ofIrradiated Fuel Outside the Reactor Vessel.
l NUMARC EALs associated with this IC include:
1 2.
Report ofvisual observation ofirradiatedfuel uncovered.
l 3.
Water levelless than (site-specific)feetfor the Reactor Refueling Cavity that will result in Irradiated Fuel Uncovering.
l The Duane Arnold EAL scheme includes the following EALs:
1.
Uncontrolled loss ofreactor cavity orfuelpool water level results in a spentfuel assembly that is NOTfully covered by water.
OR I
2.
Valid Fuel Pool water level indication (LI-3414) below 13 feet 9 inches A.
The Duane Arnold EAL #1 does not provide for the method of detection of the plant condition as is provided for in NUMARC EAL #2, i.e. " Report of visual observation ofirradiate.; fuel uncovered." This concern may be the result of the Duane Arnold EAL scheme not including EALs under ICs.
4
l l
B.
The Duane Arnold EAL scheme does not include an EAL corresponding the i
NUMARC EAL #3. Nojustification was provided for this deviation.
l l
IES Utilities Response An EAL has been added as identified in the NUMARC document. The EAL reads
" Report of visual observation ofirradiated fuel uncovered." The phrase " Uncontrolled loss of reactor cavity..." has been removed.
i An EAL that reads " Water level reading below 450", as indicated on LI4541 (floodup) l for the Reactor Refueling Cavity that will result in Uncovering Irradiated Fuel." has been added.
l Issue No. 5 NUMARC IC AA3 states:
Release ofRadioactive Material or increases in Radiation Levels Within l
the Facility that Impedes Operation ofSystems Required to Maintain Safe l
Operation or to Establish or Maintain Cold Shutdown NUMARC EALs associated with this IC include:
l 1.
Valid (site-specific) radiation monitor readings GREA TER THAN l
15 mR/hr in areas requiring continuous occupancy to maintain plant safetyfimetions.
l 2.
Valid (site-specific) radiation monitor readings GREA TER THAN l
< site specific > values in areas requiring infrequent access to maintainplant safetyfunctions.
l (Site-specific) list The corresponding Duane Arnold EAL is:
Dose rates prevent occupancy or access to areas required to achieve or maintain safe shutdown.
A.
The Duane Arnold EAL scheme did not include EALs corresponding to these l
NUMARC EALs for this IC. The condition provided in the Duane Arnold I
scheme is closely related to the NUMARC IC but does not contain site-specific l
thresholds for classifying the event.
IES Utilities Resnonse Two EALs have been added. They are " Valid area radiation monitor (RE9162) reading
[
greater than 15 mR/hr in the Control Room" and " Valid area radiation monitor (RE9168) reading greater than 500 mR/hr at the Remote Shutdown Panel IC388."
5
Issue No. 6 l
1 AS)
Boundary Dose Resultingfrom an Actual or Imminent Release of Gaseous Radioactivity Exceeds 100 mR Whole Body or 500 mR Child Thyroidfor the Actual or Projected Duration ofthe Release.
NUMARC Example EALs associated with this IC include:
1.
A valid reading on one or more ofthefollowing monitors that l
exceeds or is expected the value shown indicates hat the release may have exceeded the above criterion and irdiues the need to assess the release with (site-specificprocedure):
4.
Field survey results indicate site boundary dose rates exceeding 100 mR/hr expected to continuefor more than one hour; or analyses offield survey samples indicate child thyroid dose commitment of500 mRfor one hour ofinhalation.
The Duane Arnold EAL corresponding to NUMARC EAL #4 is:
4.
Validfield survey reading outside the site boundary above 100 mR/hr.
A.
The Duane Amold EAL scheme did not include the NUMARC condition for the child thyroid dose commitment.
B.
The Duane Arnold EAL scheme includes EALs corresponding to NUMARC EAL
- 1. The Duane Amold EAL basis document states that; 'In order to calculate suitable radiation monitor values as described in the generic methodology, use of an assumed source term mixture, use of annual average meteorology, and rounding offis required." Insufficient detail was provided to determine whether l
the " assumed source term" met the guidance for the source term in the NUMARC l
basis for this EAL.
IES Utilities Resnonse l
l Dose assessment using MIDAS is based on the EPA-400 methodology, e.g., use of Total Effective Dose Equivalent (TEDE) and Committed Dose Equivalent (CDE) Thyroid.
TEDE is somewhat different from whole body dose received from gaseous effluents, as determined by ODAM methodology, which forms the basis for the radiation monitor I
readings calculated in AUI. Whole body dose from gaseous effluents is in accordance with the generic methodology.
The gaseous effluent radiation monitors can only detect noble gases. The contribution of iodine's to TEDE and CDE Thyroid could therefore only be determined either by: (1)
[
utilizing MIDAS, or (2) gaseous effluent sampling. DAEC EAL #4 is written in terms of 6
2 TEDE and CDE Thyroid. Including the child thyroid dose commitment terminology is not applicable in this case.
The source terms used have been pre-loaded into MIDAS and are the default mixes associated with a loss of coolant accident (LOCA) and a control rod drop (CRD) as described in the UFSAR, incorporating EPA-400 guidelines. DAEC has recalculated and rewritten the EAL's associated with ASI and AGl to reflect the revised source term. The revised EAL's associated with ASl and AGl are " Valid field survey reading outside the site boundary >100 mR/hr or above 500 mR/hr CDE Thyroid." and " Valid field survey reading outside the site boundary >1,000 mR/hr or >5,000 mR/hr CDE Thyroid",
respectively.
NUMARC Recognition Category F l
Fission Product Barrier Degradation Issue No. 7 1
The NUMARC EAL methodology includes a fission product barrier matrix for determining whether or not a barrier (fuel clad, reactor coolant system, or containment) is lost or potentially lost and for classifying events based on the J
combination oflost or potentially lost barriers. The fission product barrier matrix provides multiple indications to operators to assess the status of each of the barriers.
j Classification of an event is made by determining the combination of barriers which have either been lost or potentially lost. The NUMARC guidance specifies that the following combination of barriers is indicative of a Site Area Emergency.
Loss ofBOTHFuel Cladand RCS OR Potential Loss ofBOTH Fuel Clad and RCS OR Potential Loss ofEITHER Fuel Clad OR RCS, and Loss ofANY Additional Barrier A.
The Duane Arnold EAL scheme also contains a fission product barrier matrix.
However, the Duane Arnold EAL scheme defines the combination of barriers which is indicative of a Site Area Emergency differently than the NUMARC guidance. The combination of barriers specified in the Duane Arnold EAL scheme for the Site Area Emergency is:
Loss or Potential Loss ofAny Two Barriers The Duane Arnold EAL basis document explains that using this combination of barriers makes the classification easier to understand and that no sequences are significantly affected by the simplified logic. Insufficient detail was provided in the Duane Arnold EAL basis document to verify that the Duane Arnold EAL 7
_.-.. -. ~
?
scheme meets the intent of the NUMARC guidance. The comparison table provided did not identify which EALs were being compared and did notjustify the adequacy of those combinations which would result in a Site Area Emergency j
classification in the Duane Arnold EAL which would not have resulted in a Site i
Area Emergency classification in the NUMARC guidance.
IES Utilities Resnonse The potential loss of the primary containment based on radiation / core damage and RPV level indicators can only occur if there is a loss of both the fuel clad and RCS barriers.
This is true because the primary containment barrier potential loss value is higher than the corresponding values for the same indicators that indicate loss of both the RCS and fuel clad barriers. For the primary containment atmosphere indicators, potential loss l
indicators of either torus pressure of 53 psig or elevated hydrogen levels can only result l
from significant core damage that would result from a loss of both the RCS and the fuel l
clad. Thus, for these conditions, existence of the thresholds for containment potential loss could only lead to a General Emergency declaration. That only leaves EC/OSS judgment indicators, Primary Containment Atmosphere loss indicators and the Leakage indicators to be considered.
l By their very nature, the EC/OSS Judgment indicators arejudgment calls and use of the l
NUMARC generic logic or the DAEC logic would make no difference. That leaves the l
Leakage indicators and the remaining Primary Containment Atmosphere indicators.
Since the primary containment barrier indicators are all " loss" indicators, the existence of at least a " potential loss" of either the fuel clad or the RCS barriers will always result in a Site Area Emergency whether or not the NUMARC logic or the logic used at the DAEC and other plants is applied.
l Issue No. 8 The NUMARC EAL for the loss and potential loss of the fuel clad barrier based on reactor vessel water level indications are:
Loss:
j Level LESS TIMN (site-specific) value l
l Potential Loss:
i Level LESS TIMN (site-specific) value l
4 8
l The corresponding Duane Amold EALs are:
l Loss:
l i
RPVLevel below -30 inches and cannot be restored Potential Loss:
l l
RPVLevel below -15 inches and cannot be restored A
The Duane Amold EAL basis document did notjustify the addition of"cannot be restored" to these EALs. It is not clear why the loss or potential loss cannot be l
based on the level alone. The addition of the condition "cannot be restored" may l
cause confusion and/or delay classification. (this same comment also applies to the Loss of Reactor Coolant System Barrier EAL based upon reactor vessel level.)
IES Utilities Resnonse The phrase "cannot be restored" will be removed. This will be applied to all applicable i
level statements contained on the Fission Barrier Table.
Issue No. 9 The Duane Arnold EAL scheme includes the following EAL:
l Core damage assessment determines at least 5% fuel clad damage The Duane Amold EAL basis document states:
It is intended that determination ofbarrier loss be made whenever the indicator threshold (for the containment monitor) is reached until such time that core damage assessment isperformed, at which time direct use ofcontainment rad monitor readings is no longer required.
A.
The Duane Arnold EAL scheme did not include a statement corresponding to the statement in the Duane Amold basis document regarding the use of the containment rad monitor EAL. This may cause confusion when classifying an event.
l l
9 l
l
1
~
IES Utilities Resoonse The Fuel Clad Barrier statements have been rewritten as follows:
Fuel damage assessment (PASAP 7.2) determines at least 5% fuel clad damage OR Fuel damage is indicated by any of the following:
[
Valid drywell rad monitor reading above 7E+2 R/hr OR
[
Valid torus rad monitor reading above 3E+1 R/hr OR
[
Coolant activity above 300pCi/gm DOSE EQUIVALENT I-131 Issue No.10 The NUMARC EAL for the potential loss of the reactor coolant system barrier based on RCS leak rate indications includes the following conditions:
l Unisolable primary system leakage outside the drywell as indicated by area temp or area radalarm The corresponding Duane Arnold EAL is:
Unisolable primary system leakage outside the drywell as indicated by ARMS or in-plant radiological surveys A.
The Duane Arnold EAL basis document did notjustify not including the condition "as indicated by area temp"in the Duane Arnold EAL. (This comment l
also applies to the same Duane Arnold EAL listed under the Loss of Containment Barrier column of the fission product barrier table.)
IES Utilities Resoonse The phrase "as indicated by area temperatures" was added to all applicable locations on the Fission Barrier table.
Issue No.11 The NUMARC EAL for the potential loss of the RCS barrier based on drywell
(
pressure indications is:
J l
Pressure Greater than (site-specific) psig l
l 10
m' l
~
The NUMARC basis for this EAL states:
The (site-specific) drywellpressure is based on the drywell high pressure alarm setpoint andindicates a LOCA. A higher value may be used if supporting documentation is provided which indicates the chosen value is less than the pressure which would be reachedfor a 50 gpm Reactor Coolant System leak.
I The corresponding Duane Amold EAL is:
Drywell cooling operating AND drywellpressure above 2 psig The Duane Arnold EAL basis document states:
j There is no sigmficant dev;ationfrom the generic indicator. The (site-specific) valuefor this loss indicator corresponds to the drywell high pressure ECCSinitiatic; signalsetpoint of2.0psig.
A.
The Duane Arnold EAL basis does not address why the Duane Arnold EAL uses the ECCS initiation drywell pressure setpoint instead of the alarm setpoint as specified in the NUMARC guidance.
13.
It is not clear whether drywell cooling operation may be automatically isolated when drywell pressure exceeds 2 psig and whether this may cause confusion when classifying the event.
IES Utilities Resoonse l
The DAEC design is that of a GE Mark I Containment. During reactor operation, drywell pressure is maintained between 0.5 and 1.0 psig. The high pressure alarm setpoint of 1.5 psig was not selected, as this is too close to the nonnal operating pressure band, and could be exceeded for reasons other than a RCS leak. Analysis at the DAEC shows that a 50 gpm RCS leak would result in a 2 to 3 psig pressure rise over a six minute time period.
Since a 2 psig rise would be above the ECCS initiation setpoint, it is more practical to use the ECCS initiation setpoint of 2 psig for this EAL.Drywell cooling does not automatically isolate at 2 psig in the drywell, at the DAEC. Therefore, no confusion would result when classifying the event.
Issue No.12 The NUMARC EALs for the loss of the Containment barrier based on drywell l
pressure indications are:
l Rapid unexplained decreasefollowing initial increase or Drywellpressure response not consistent with LOCA conditions l
A.
The Duane Arnold EAL scheme did not include these EALs and the Duane l
Arnold EAL basis document did notjustify this deviation.
I1
IES Utilities Resnonse The NUMARC EAL's for Primary Containment Barrier Loss for Drywell Pressure have been added as follows:
Rapid unexplained decrease following initial increase OR l
Drywell pressure response not consistent with LOCA conditions.
1 The basis information to support the above conditions has been inserted into the DAEC l
basis document to support these EAL's.
l Issue No.13 The NUMARC EAL for the potential loss of the containment barrier based on reactor pressure vessel water level is:
Reactor vessel water level LESS THAN (site-specific) value and the maximum core uncovery time limit is in the UNSAFE region The corresponding Duane Arnold EAL is:
1 RPV Level below -40 inches AND no injections source available A.
The Duane Arnold EAL does not appear to meet the intent of the NUMARC EAL. Two concerns have been identified with the Duane Arnold EAL. One is that the term "not available' has not been defined and may cause confusion when classifying the event. The second concern is that even if the injection source is available, if the water level was to remain below 40 inches for a given amount of time, the barrier should be considered potentially lost. As stated in the NUMARC EAL basis: "if emergency operating procedures have been ineffective in restoring reactor vessel level within the maximum core uncovery time limit, there is not a success path.". Whether or not the procedures will be effective should be apparent within the time provided. The Emergency Director should make the declaration as soon as it is determined that the procedures have been, or will be, ineffective."
JES Utilities Response l
The phrase "...AND no injection source available" has been removed, as this is just a j
restatement of given information in EOP's. Also the Maximum Core Uncovery Time Limit (MCUTL) is addressd in Q&A Fission Product Barriers - BWR #10. Which states that this is the improper use of this chart considering the input assumptions for the cun'e.
12 l
f NUMARC Recognition Category H llazards and Other Conditions Affecting Plant Safety Issue No.14 l
NUMARC IC 11U1 includes the following EAL:
3.
Assessment by the control room that an event has occurred.
A.
The Duane Arnold EAL scheme did not include an EAL corresponding to this i
EAL and no justification was provided for this deviation.
l IES Utilities Resnonse l
An EAL stating " Assessment by the control room that an event has occurred" along with l
supporting basis information has been included.
l Issue No.15 l
NUMARC IC HUI includes the following EAL:
4.
l'ehicle crash into plant structures or systems within protected l
area boundary.
i l
The NUMARC Basis for this EAL explains that:
Automobiles, trucks, andforkhfts are also vehicles within the context of this EAL The key is whether or not the vehicle can potentially cause sigmficant damage to plant structures.
The corresponding Duane Arnold EAL is:
7.
Vessel or vehicle collision with structures or equipment required for safe shutdown The Duane Arnold basis document states that:
i l
DAEC EAL 7 addresses vessel (aircraft) or vehicle (truck or train) crashes with structures or equipment requiredfor safe shutdown A.
The Duane Arnold EAL did not define the term " structures or equipment required for safe shutdown." It is not clear that users of the EAL procedure will be able to ascertain what are the structures or equipment required for safe shutdown. (This comment applies to the other EALs under IC HUI.)
B.
The Duane Arnold basis document deviates from the NUMARC guidance by specifically not including automobiles and forklifts as vehicles for this EAL.
13
1 l
IES Utilities Response The table located adjacent to 11U2 titled " Systems & Equipment of Concern" is intended l
to illustrate the equipment or structures required for safe shutdown.
" Automobiles" and " forklifts" have been added to the basis document.
Issue No.16 NUMARC IC 1101 includes the following EAL:
)
5.
Report byplant personnel ofan unanticipated explosion within l
protected area boundary resulting in visible damage topermanent l
structure or equipment.
l The corresponding Duane Arnold EAL is-3.
Visible damage ofstructures or equipment requiredfor safe j
shutdown i
5.
Explosion withinplantprotectedarea A.
Duane Arnold EAL #3 is not specific as to the cause of the damage which would result in the Unusual Event classification. It is not clear whether " damage" to I
equipment from maintenance errors or operational errors would M classified under this EAL.
B.
Duane Arnold EAL #5 does not include the NUMARC condition of"resulting in visible damage...." No justification was provided for this deviation.
l IES Utilities Resnonse EAL's #3 and #5 were combined into a single EAL consistent with the NUMARC EAL l
which states " Report of an unanticipated explosion within the protected area boundary l
resulting in visible damage to permanent structures or equipment".
Issue No.17 L
NUMARC IC HUI includes the following EAL:
6.
Report ofturbinefailure resulting in casingpenetration or damage to turbine or generator seals The corresponding Duane Arnold EAL is:
6.
Turbinefailure causing observable casing damage i
I 14
A.
Contrary to the NUMARC EAL, the Duane Arnold EAL did not include the l
condition " damage to turbine or generator seals."
i i
s IES Utilities Resnonse
" Report of turbine failure resulting in casing penetration or damage to turbine or generator seals" has been added to the DAEC EAL's.
i j
Issue No.18 4
NUMARC IC HU2 includes the following EAL:
1.
Fire in buildings or area contiguous to any ofthefollowing (site-specific) areas not extinguished within 15 minutes ofcontrol room notification or verification ofa control room alarm:
(Site-specific) list The corresponding Duane Arnold EAL is:
1 1.
Fire within safe shutdown area NOTextinguished within 15 minutes ofcontrol room notification or verification ofcontrol room alarm.
A.
The NUMARC EAL specifies " buildings or areas contiguous to...." The corresponding Duane Arnold EAL limits the areas considered to only " safe shutdown area (s)." This same list of areas is included in the related Alert level EAL. The areas applicable under the Unusual Event EAL is broader than the areas applicable under the Alert level EAL.
IES Utilities Resnonse The revised DAEC EAL reads " Fire in buildings or areas contiguous to any of the following areas not extinguished within 15 minutes of control room notification or verification of a control room alarm."
Reactor, Turbine, Control, Administrative / Security buildings Pump house Intake structure The basis information has been updated to identify the above facilities.
4 I
l l
15
l I
Issue No.19 1
NUMARC IC HU3 includes the follewing EAL:
1 2.
Report by local, county or State offic ?forpotentialevacuation of site personnel based on offsite event l
The corresponding Duane Arnold EAL is:
l 2.
Notification ofnear site release that may require evacuation.
l A.
The term "near site"is not defined in the Duane Amold EAL. In addition, it is not clear that including this term is necessary for the Duane Arnold EAL to meet the intent of this NUMARC EAL.
IES Utilities Response The DAEC EAL has been reworded as follows: " Report by local, county or State official for potential evacuation of site personnel based on an ofTsite event".
1 Issue No. 20 l
NUMARC IC HU4 includes the following EAL:
2.
Other security events as determinedfi om (site-specific) Safeguards Contingency Plan.
1 The corresponding Duane Amold EAL is.
i 1.
Suspected sabotage device discovered in plant switchyard.
The Duane Amold EAL basis document states:
l Other (site-specific) security events ofconcern at DAEC include discovery ofa suspected sabotage device in the plant switchyard, which is located outside the protected area.
A.
It is not clear from the information provided whether Duane Arnold EAL #2 l
includes all the applicable security events in the Duane Arnold Safeguards Contingency Plan.
IES Utilities Resoonse The information provided is complete and consistent with the DAEC Security l
Contingency Plan, Revision 33. Due to the nature of the safeguards information contained in that plan it is exempt from public disclosure pursuant to 10CFR73.21.
16
Issue No. 21 NUMARC IC HA1 includes the following EAL:
3.
Report ofany visible structural damage on any ofthefollowingplant structures:
l Reactor Building Intake Building Ultimate Heat Sink Refueling WaterStorage Tank Diesel Generator Building Turbine Building Condensate Storage Tank ControlRooms Other (Site-Specific) Structures A.
The Duane Arnold EAL scheme did not include an EAL corresponding to this EAL and did not justify this deviation.
IES Utilities Resnonse The DAEC EAL corresponding to NUMARC IC HAl EAL #3 is; " Report to control l
room of damage affecting ability to achieve or maintain safe shutdown". The DAEC l
basis document addresses this in Section H page 9. The DAEC basis document also identifies all locations applicable to this EAL in the table labeled " Safe Shutdown Areas".
Issue No. 22 NUMARC IC HAl includes the following EAL:
3.
Vehicle crash affecting plant vital areas The corresponding Duane Arnold EAL is:
l 6.
Vessel or vehicle collision affecting ability to achieve or maintain 1
The Duane Arnold EAL deviates from the NUMARC EAL by including the condition that the collision affects the ability to achieve or maintain safe shutdown. Nojustification was provided for this deviation. It may be difficult to make a definitive determination whether the vehicle collision did affect the ability to achieve or maintain safe shutdown. It is not appropriate to delay classification in order to make this determination. (This comment also applies to Duane Arnold EAL HA1, #5) 17
l l
IES Utilities Resnonse HAl is intended to be a " confirmed" collision affecting a plant safe shutdown area (vital area). The EAL has been rewritten as follows: " Vehicle crash affecting plart vital areas".
i Issue No. 23 l
NUMARC IC HA4 includes the following EAL:
2.
Other security events as determinedfrom (site-specific) Safeguards Contingency Plan.
A.
The Duane Arnold EAL scheme did not include an EAL corresponding to this EAL. The Duane Arnold EAL basis document states that: " Based on information provided by DAEC Security, generic EAL 2 is unnecessary at DAEC." It is not clear what, if any, security events were considered in making this determination.
This comment also applies to the corresponding Site Area Emergency IC HSI.
For HS1 it appears that a sabotage device discovered in the plant vital are as should be included as an EAL.
IES Utilities Resnonse
" Sabotage device discovered in the plant protected area" as an EAL under HA4, has been added. The EAL " Sabotage device discovered in the plant vital area" has also been added under HSI.
Issue No. 24 NUMARC IC HA5 includes the following EAL:
1.
Entry into (site-specific) procedurefor control room evacuation.
The corresponding Duane Arnold EAL is:
Control Room evacuation procedures have been initiated A.
Contrary to the NUMARC guidance, the specific Duane Arnold procedure for control room evacuation is not identified in the EAL.
i l
IES Utilities Resnonsg A reference to Abnormal Operating Procedure 915," Shutdown Outside Control Room",
was incorporated into this EAL.
t 18
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Issue No. 25 l
NUMARC IC HS2 includes the following EAL:
l 1.
Thefollowing conditions exist:
i l
a.
Control room evacuation has been initiated
(
AND
\\
b.
Control ofthe plant cannot be establishedper (site-l specific) procedure within (site-specific) minutes.
The corresponding Duane Arnold EAL is.
Control room has been evacuated AND control ofplantfrom Remote i
Shutdown Panel 1C388 NOT established within 20 minutes.
The basis for the NUMARC EAL states:
(Site-specific) timefor transfer based on analysis or assessments as to how quickly control must be reestablished without core uncovering and/or core damage. This time should not exceed 15 minutes. (emphasis udded)
The Duane Arnold basis document states:
Operator control within 20 minutes would not impact the integrity ofthe fuel clad, the reactorpressure vessel, and the primary containment.
A.
The Duane Arnold EAL basis did notjustify why the time limit to classify this event should exceed 15 minutes. For instance, the Duane Arnold basis did not describe why more than 15 minutes is needed for determining whether control is established at the remote shutdown panel IES Utilities Resnonse Suppart has been added to the DAEC basis document explaining why the basis for 20 minutes vs.15 minutes, as recommended by the generic document. DAEC physically has satellite panels associated with the remote shutdown panel at various locations within the plant. General Electric Report MDE-44-0386," Safe Shutdown Appendix R Analysis for l
DAEC", March 83, identifies that for the DAEC, it is not possible to reposition all the required switches at all the remote locations in less than 15 minutes Therefore, DAEC has allowed 20 minutes to line up the remote shutdown panel.
l l
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Issue No. 26 l
l NUMARC IC HG1 contains the following EALs:
1.
Loss ofphysical control ofthe control room due to security event.
l OR 2.
Loss ofphysical control ofthe remote shutdown capability due to security event.
The corresponding Duane Arnold EALs are:
l 1.
Loss ofphysical control ofthe control room OR 2.
Loss ofphysical control ofremote shutdown capability A.
Contrary to the NUMARC guidance, the Duane Arnold EALs do not include the condition "due to security event." Therefore an event where the control room must be evacuated for reasons other than due to a security event may erroneously be classified under this EAL.
l l
IES Utilities Resnonse Due to the layout of the DAEC EAL table, the words,"...due to security event" is unnecessary because the associated EAL's are identified within the " Security" event type.
This is consistant with current plant practice and consistent with the NUREG - 0654 based EAL tables, currently in use at the DAEC.
NUMARC Recognition Category S System Malfunction l
Issue No. 27 NUMARC IC EAL SUI contains the following EALs:
1.
Thefollowing conditions exist:
Loss ofpower to (site-specific) transformersfor greater a.
than 15 minutes AND b.
At lease (site-specific) emergency generators are supplying power to emergency busses.
20 l
I I
The corresponding Duane Arnold EAL is:
Loss ofoffsite power lasting more than 15 minutes l
A.
Contrary to the NUMARC guidance, the Duane Arnold EAL does not identify site-specific transformers, loss of power to which constitutes " loss of all offsite power".
IES Utilities l
" Loss of Offsite Power"is consistent with the DAEC Operation's Department terminology for the conditions of SUI. The NUMARC conditions as outlined in the NUMARC example EAL's would be less clear to the operators at the DAEC.
Issue No. 28 NUMARC IC SU3 includes the following EAL:
1.
Thefollowing conditions exist:
a.
Loss ofmost or all (site-specific) annunciators associated j
with safety systemsfor greater than 15 minutes.
AND b.
Compensatory non-alarming indications are available AND c.
In the opinion ofthe Shift Supervisor, the loss ofthe annunciators or indicators requires increased surveillance to safely operate the unit (s)
AND d.
Annunciator or indicator loss does not resultfrom planned action.
The corresponding Duane Arnold EAL is:
Unplanned Loss ofannunciators onpanels 1C03,1C04, and 1C05 lasting more than 15 minutes AND compensatory non-alarming indications are available.
A.
The Duane Arnold EAL is inconsistent with the NUMARC guidance in that it l
specifies loss of all annunciators. The Duane Arnold EAL basis document states that the annunciators share a common power supply and therefore it is not necessary to include the condition of"most annunicators." It is not clear that there is no event which could result in a loss of most annunciators and no reason was given for why a loss of most annunciators would not meet the intent of the NUMARC guidance.
21
._..__._.__._______-_..__.___.___..._.-._m_
j IES Utilities Resnonse i
DAEC rewrote the EAL as follows:
i Unplanned loss of most annunciators on Panels 1C03, IC04, and 1C05 lasting more than 15 minutes.
[
AND f
Compensatory non-alarming indications are available.
Issue No. 29 l
NUMARC IC SU4 includes the following EALs:
I 1.
(Site-specific) radiation monitor readings indicatingfuel clad
{
degradation greater than technical specification limits.
1 1
2.
(Site-specific) coolant sample activity value indicatingfuel clad degradation greater than technical specification limits.
The corresponding Duane Arnold EALs are:
1.
Valid Pretreat RM-4104 rad monitor reading above 4E+3 mR/hr 2.
Coolant activity above 1.2 pCi/mi DOSE EQUIVALENTl-131 A.
The Duane Arnold basis document describes the technical specification basis used for developing these EALs. It is not clear why technical specification 3.6.b.2 was used for the basis for Duane Arnold EAL #1 whereas technical specification 3.6.b.1 was used for the basis for Duane Arnold EAL #2.
IES Utilities Resnonse As stated in the DAEC basis document, Technical Specification 3.6.B.I.a is the basis for i
the DAEC EAL #1 and Technical Specification 3.6.B.I.b is referenced for DAEC EAL
- 2. Technical Specification 3.6.B.I.b is the Technical Specification that requires a shutdown, after exceeding the iodine spike value for longer than 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, and is intended to separate continuous from spike conditions.
1 i
4 i
22 1
..l
Issue No. 30 l
NUMARC IC SU5 contains the following EAL:
(
1.
Thefollowing conditions exist:
a.
Unidentyled or pressure boundary leakage greater than 10 HPm OR b.
Identified leakage greater than 25 gpm The corresponding Duane Arnold EAL is:
1 Unidentifiedleakage above 10 GPAf OR TotalRCSleakage above 35 GPAf OR Afain steam line break as determinedfrom annunciators orplant personnelreport A.
The Duane Arnold EAL is not consistent with the NUMARC guidance in that it does not specify a value for pressure boundary leakage. No justification was provided for this deviation.
l I
B.
The Duane Arnold EAL is not consistent with the NUMARC guidance in that it i
specifies 35 gpm for the total RCS leakage instead of 25 gpm as is specified in the NUMARC guidance. The NUMARC guidance states that this IC is included as l
an Unusual Event because it may be a precursor of more serious conditions. The l
Duane Arnold basis document does not address why a 25 gpm total RCS is not l
indicative of a potential degradation of the level of safety at Duane Arnold and therefore is not an Unusual Event.
IES Utilities Response This EAL has been revised to be consistent with the NUMARC guidance. The EAL now reads:
Unidentified or pressure boundary leakage greater than 10 gpm.
OR l
Identified leakage greater than 25 gpm 4
23
Issue No. 31 NUMARC IC SU6 contains the following EALs:
i 1.
Loss ofall (site-specific list) onsite communication capability affecting the ability to perform routine operations.
2.
Loss ofall (site-specific) ofsite communications capability The corresponding Duane Arnold EALs are:
1.
Loss ofALL onsite electronic communication methods 2.
Loss ofALL electronic communication methods with government agencies A.
Contrary to the NUMARC guidance, a site-specific list of communication -
capabilities was not included in these EALs. The concern with this deviation is that the user of the classification procedure may not be readily able to ascertain I
whether the EALs are met or not because of the lack of site-specific information.
IES Utilities Resnonse Consistent with the NUMARC basis information, the EAL's have been revised to state-I 1)
Loss of all onsite telephone and radio communication methods (PABX, direct-ring, UHF, and radiological survey radio systems.)
2)
Loss of ALL electronic communication methods with government agencies (PABX, direct-ring, ENS, microwave and police radio).
l Issue No. 32 NUMARC IC SU7 contains the following EAL:
1.
Either ofthefollowing conditions exist:
a.
Unplanned Loss of Vital DCpower to required DC busses based on (site-specific) bus voltage indications.
AND b.
Failure to restore power to at least one required DC bus within 15 minutesfrom the time ofloss.
The corresponding Duane Arnold EAL is:
Complete Loss of125 VDC lasting more than 15 minutes 24 l
A.
Contrary to the NUMARC guidance, the Duane Arnold EAL did not specify the applicable vital buses in this EAL and did not specify what voltage level constitutes a loss of DC. The concern with this deviation is that classification may be delayed or an event improperly classified due to the lack of specific information. (This comment also applies to IC SS3) l-IES Utilities Resnonsg The DAEC EAL for SU7 has been revised to read "The following conditions exist:
Unplanned Loss of Div 1 and Div 2125 VDC to required busses based on bus voltage less than 105 VDC indicated.
l AND l
Failure to restore power to at least one required 125 VDC bus within 15 minutes from time ofloss.
l The basis has been revised as follows: There is no significant deviation from the generic EAL. Unplannedloss of Div 1 and Div 2125 VDC busses excludes scheduled maintenance and testing activities. Under the conditions of concern, AOP 302.1," Loss of 125 VDC Power", would be entered. The DAEC EAL's address the loss of both i
divisions of the 125 VDC systems consistent with AOP 302.1.
1 The 125 VDC system is divided into two independent divisions - Division I (1DI) and Division II (1D2) - each supplied by separate AC and DC (battery) power supplies. Loss of both 125 VDC Divisions could compromise the ability to monitor and control the removal of decay heat during cold shutdown or refueling operations. These EAL's are intended to be anticipatory in as much as the operating crew may not have necessary.
indication and control of equipment needed to respond to the loss. If this loss results in
' the inability to maintain cold shutdown, the escalation to an Alert will be per SA3 "RCS temperature rise that is not allowed by procedures that will result in RCS temperature above 212 F".
Bus voltage is based on the minimum bus voltage necessary for the operation of safety related equipment and may be indicated by the illumination of annunciators "125 VDC System 1 Trouble" on IC08A A-9 and/or"125 VDC System 2 Trouble" on 1C08B A-4.
The EAL for SS3 has been rewritten as follows " Complete Loss of Div i and Div 11 125 VDC Lasting More Than 15 Minutes".
l 3
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i Issue No. 33 NUMARC IC SA3 contains the following EAL-i l
1.
Thefollowing conditions exist:
l Loss of(site-specific) technical specification required a.
fimetions to maintain cold shutdown.
l AND b.
Temperature increase that either:
l Exceeds technical specification cold shutdown temperature limit OR Results in uncontrolled temperature rise approaching cold shutdown technical specification limit.
The corresponding Duane Arnold EAL is:
l RCS temperature rise that is not allowed byprocedures or Tech Specs that will result in RCS temperature above 212 F.
A.
The Duane Arnold EAL deviates from the NUMARC EAL by including the condition that the temperature rise is "not allowed by procedures or Tech Specs" rather than "the loss of tech spec functions." The concern is that the conditions specified in the Duane Arnold EAL will make classifying events more difficult and that some events classified under the NUMARC EAL scheme may not be l
classified under the Duane Arnold EAL scheme, 1
i l
B.
The Duane Arnold EAL deviates from the NUMARC guidance by not including the condition of" uncontrolled temperature rise approaching cold shutdown l
technical specification limit." This may result in delaying classifications. This deviation was notjustified in the Duane Arnold EAL basis document.
1 IES Utilities Response The revised wording of this EAL is:
Loss of decay heat removal systems required to maintain cold shutdown AND Temperature rise that exceeds 212"F OR Uncontrolled temperature rise approaching 212 F 26 l
The loss of monitoring and removal of decay heat during shutdown conditions is currently governed by DAEC's procedure AOP 149," Loss of Dec Heat Removal."
i l
The DAEC EAL i3 written to imply a RCS temperature rise abos
" F that is not l
allowed under plant procedures. This corresponds to the inabili-tain required l
temperature conditions for Cold Shutdown. " Uncontrolled" me.
. tem temperature increase is not the result of planned actions by the plam sut1. Minor cooling interruptions occurring at the transition between 1101 Shutdown and Cold Shutdown or temperature changes that are permitted to occur during the establishment of alternate core l
cooling would not require an unnecessary declaration of an Alert.
i l
Issue No. 34 l
NUMARC IC SS2 includes the following EAL.
(Site-specific) indications exist that automatic and manual scram were not successfid l
The corresponding Duane Arnold EAL is:
All control rods NOT inserted to at least position 02 AND boron injection with SBLC is required.
A.
The Duane Arnold EAL deviates by including the condition that " boron injection with SBLC is required." This condition may result in delaying classification. If the reactor is producing more heat than the maximum decay heat load for which the safety systems are designed then conditions exist that lead to imminent loss or potential loss of both fuel clad and the RCS and therefore a Site Area Emergency classification is warranted. It is not appropriate to wait until baron injection is procedurally mandated to classify the event.
IES Utilities Resnonse 1
This EAL has been reworded as follows:
Failure of automatic and manual scram AND Power remains above 5%
OR Boron injection is required.
l This change addresses the issue where an automatic and manual scram are not considered successful if actions away from the reactor control console are required to scram the l
reactor. Under these conditions, the reactor is producing more heat than the maximum decay heat load for which the safety systems are designed. These conditions could lead to imminent loss or potential loss of both fuel clad and RCS.
27
Issue No. 35 NUMARC IC SS4 states:
Complete loss ofFunction Needed to Achieve or Maintain Hot Shutdown l
l NUMARC EALs associated with this IC include:
1.
Complete loss ofany (site-specific) function requiredfor hot shutdown The corresponding Duane Arnold EAL is:
Adequate core cooling conditions CANNOT be achieved or maintained OR Reactor CANNOT be brought subcritical A.
The Duane Arnold EAL does not include plant specific indication for determining whether adequate core cooling conditions exist. This could make this EAL difficult to use.
IES Utilities Resoonse This EAL has been reworded as follows:
l EOP Graph 4, Heat Capacity Limit is exceeded OR l
Reactor CANNOT be brought suberitical This EAL addresses complete loss of functions, including ultimate heat sink and reactivity control, required for hot shutdown with the reactor at pressure and temperature.
l Under these conditions, there is an actual major failure of a system intended for the protection of the public. If the main condenser is unavailable and the Torus is threatened, l
this would be a plant condition that would correspond to an actual major failure of a l
system intended for the protection of the public. This condition would also impact
" adequate core cooling" conditions. The reactivity condition criteria is addressed by l
maintenance of required shutdown margin.
l l
l l
1 I
f I
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l 1
Issue No. 36 NUMARC IC SGI contains the following EAL:
1.
Prolonged loss ofall ofsite and onsite ACpower as indicated by:
a.
Loss ofpower to (site-specific) transformers.
AND b.
Failure of(site-specyle) emergency dieselgenerators to supplypower to emergency busses.
AND l
l c.
At least one ofthefollowing conditions exists:
l
/
Restoration ofat least one emergency bus within (site-specific) hours is NOTlikely
'OR (Site-specific) indication ofcontinuing degradation ofcore cooling based on Fission Product Barrier monitoring.
l The corresponding Duane Arnold EAL is:
l 1
l Loss of Voltage on Buses 1A3 and 1A4 and ANYofthefollowing l
Restoration ofpower to either Bus 1A3 or 1A4 is NOT likely within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> RPVlevelremains indeterminate l
RPYlevelremains below-30 inches A.
The terms " remains indeterminate" and " remains below -30 inches" are not defined in the Duane Arnold EAL. Using undefined terms such as these may result in confusion when classifying an event. In addition, if a station blackout l
condition occurred and water level reached the top of active fuel, plant conditions warrant classifying the event as a General Emergency without waiting to determine if the level is going to " remain" less than top of active fuel.
l IES Utilities Resnonse
" Loss of Voltage on Buses 1 A3 and 1 A4" addresses the NUMARC EAL statements of
" Loss of Power to (site-specific) transformers AND failure of(site-specific) emergency diesel generators to supply power to emergency busses." " Restoration of power to either Bus I A3 or 1 A4 is NOT likely within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />" is synonymous with " Restoration of at 29 l
~
i i
least one emergency bus within (site-speciSc) hours is NOT likely". The DAEC removed the word " remains" from the EAL table under SGl. The EAL wording has been revised j
i to read,"RPV level indeterminate, RPV level below -30 inches. This wording is i
synonymous with "(site-speciSc)" indication of continuing degradation of core cooling based on Fission Product Barrier monitoring. DAEC has stated the EALs in terms that are familiar to our operators by extracting those words directly from our EOP's.
The EOP basis document for DAEC clearly identi6es that adequate core coohng is i
l assured for the DAEC at a level of-30 inches. Identifying a level that is not consistent with our EOP's and EOP basis document may add to operator confusion and premature escalation to a General Emergency.
l i
l Issue No. 37 l
NUMARC IC SG2 contains the following EALs:
)
l 1.
(Site-specific) indications exist that automatic and manual scram I
were not successful AND 2.
Either ofthefollowing:
a.
(Site-specific) indications exist that the core cooling is extremely challenged OR b.
(site-specific) indications exist that heat removalis.
l extremely challenged.
t f
The corresponding Duane Arnold EAL is:
l l
c l
Entry into A TWS EOP-RP V Control is required and BOTH of the following:
l Reactorpower is expected to remain above 5% or CANNOT be l
determined AND Main condenser is NOTavailable l
A.
It is not clear that the condition of the main condenser not being available is a i
suf6cient indication of an extreme challenge to heat removal. The NUMARC EAL guidance state that "For DWRs (site-specine) considerations include inability to remove heat via the main condenser, or via the suppression pool or torus (e.g. due to high pool water temperature). The Duane Arnold EAL did not l
include indications regarding heat removal via the suppression pool.
i 30 i
,?
,b.
[
- B.
No condition equivalent to the NUMARC condition "(Site-specific) indications exist that the core cooling is extremely challenged" was provided in the Duane l
Arnold EAL. The NUMARC guidance states,"For BWRs, the extreme challenge of the ability of cool the core is intended to mean that the reactor vessel water l
level is below 2/3 coverage of active fuel." The Duane Arnold EAL did not include a comparable EAL for this condition."
l C.
Contrary to the NUMARC guidance the Duane Arnold EAL includes the
[
condition " Reactor power is expected to remain above 5% or CANNOT be determined." Furtherjustification is needed to determine whether the addition of this condition meets the intent of the NUMARC EAL. In addition, the term "is i
expected to remain above 5%" is not defined in the Duane Amold EAL.
t IES Utilities Resnonse i
This EAL has been reworded as follows:
Entry into ATWS EOP-RPV Control is required i
AND-RPV level cannot be maintained above -30 inches OR EOP Graph 4 Heat Capacity Limit is exceeded.
The NUMARC condition, (Site-specific) indications exist that automatic and manual scram were not successful is addressed by " Entry into ATWS EOP-RPV Control is required."
The NUMARC condition, (Site-specific) indications exist that the core cooling is extremely challenged is addressed by "RPV level cannot be maintained above -30 inches."
The NUMARC condition, (Site-specific) indications exist that heat removal is extremely challenged is addressed by "EOP Graph 4 Ileat Capacity Limit is exceeded" 31 i
-