ML20134K820
| ML20134K820 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 11/13/1996 |
| From: | Ohanlon J VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 96-517, NUDOCS 9611200044 | |
| Download: ML20134K820 (6) | |
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VIRGINIA ELucTnIc Axn Powen Coxiwxy HIcnwoxo,VUtGINIA 20261 November 13, 1996 U. S. Nuclear Regulatory Commission Serial No.96-517 Attention: Document Control Desk NAPS /JHIJSAH R1 Washington, D. C. 20555 Docket Nos.
50-338 50-339 License Nos.
NPF-4 NPF-7 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 BEPLY TO NRC INSPEC MON REPORT NOS. 50-338/96-08 AND 50-339/96-08 j
We have reviewed your letter of September 30,1996, which described an exercise weakness identified during the plume exposure portion of our North Anna Power Station emergency preparedness exercise conducted on August 13,1996. Our reply to the assessed oxercise weakness is enclosed as Attachment 1.
The basis for the stated weakness does not appear to accurately reflect activities conducted du:ing the course of the exercise. This response includes an analysis and summary of events surrounding the timely transmittal of dose assessment information to offsite authorities, and indicates an acceptable response was demonstrated.
Accordingly, it is requested that the exercise weakness be rescinded.
The exercise critique process did, however, acknowledge the need to improve some aspects of our assessment process. Those areas of the assessment process identified as needing improvement are also described in Attachment 1. A task team has been established to address these concerns.
No new commitments are intended as a result of this letter. Please contact us should you have any questions or require further information related to this matter.
Very truly yours, 24 l
h James P. O'Hanlon Senior Vice President - Nuclear Attachment 9611200044 961113 PDR ADOCK 05000338 G
PDR 200000
cc:
U. S. Nuclear Regulatory Commission 4
Region 11 101 Marietta Street, N.W.
l Suite 2900 Atlanta, Georgia 30323 Mr. R. D. McWhorter NRC Senior Resident inspector l
North Anna Power Station
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ATTACHMENT 1 f
REPLY TO EXERCISE WEAKNESS INSPECTION REPORT NOS. 50-338/96-08 AND 50-339/96-08 j
NRC STATED EXERCISE WEAKNESS; NRC Inspection Report' No. ' 50-338, 339/96-08 cites the following observation as evidence of an apparent exercise weakness:
1 "However, due to errors made when inputting to the computerized dose projection model in the LEOF, the report of radiological conditions was not
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provided until 1:04 p.m. This failure to provide a dose assessment following the j
initiation of a radiological release in a timely manner was identified as an j
exercise weakness (IFl 50-338,339/96008-01, Failure to provide a timely report of radiological conditions following a release)."
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RESPONSE
i We believe that the basis for the weakness does not appear to accurately reflect i
activities conducted during the course of the emergency exercise. A detailed analysis of documentation associated with this portion of the exercise was conducted, and key.
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utility and State responders were interviewed with regard to' development and communication of related dose assessment calculations. This information was used to
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re-create a sequence of events which is enclosed as Figure 1.
l The sequence of events begins with a simulated radiological release occurring at 1205 i
hours. A General Emergency was classified at 1206 hours0.014 days <br />0.335 hours <br />0.00199 weeks <br />4.58883e-4 months <br />. The first dose assessment
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calculation produced following the start of the release was Meteorological Information l
and Dose Assessment System (MIDAS) Run No. 6. MIDAS systematically averages i
meteorological parameters every fifteen minutes and posts this average to an intemal j
data file. Typically, these postings occur at 7.5,22.5,37.5 and 52.5 minutes after the hour, prompting the user, in this case, to wait until about 1208 hours0.014 days <br />0.336 hours <br />0.002 weeks <br />4.59644e-4 months <br /> to commence dose projection calculations using the updated, averaged release information.
MIDAS Run No. 6 is time stamped at 1211 hours0.014 days <br />0.336 hours <br />0.002 weeks <br />4.607855e-4 months <br />. This "run time" indicates the time that the user selected an accident type from the list of available options in MIDAS.
Results of MIDAS Run No. 6 were the basis for the initial Report of Radiological Conditions that was transmitted to the State. The calculation was completed at about 1218 hours0.0141 days <br />0.338 hours <br />0.00201 weeks <br />4.63449e-4 months <br />, and a system print of MIDAS Run No. 6 was proauced at approximately 1222 hours0.0141 days <br />0.339 hours <br />0.00202 weeks <br />4.64971e-4 months <br />.
Personnel then commenced a review of the results, confirming the initial Protective
- Action Recommendation (PAR) was bounding. This review included the Radiological Assessment Coordinator, the Recovery Manager, and State Bureau of Radiological 4
l Health representatives stationed at the Local Emergency Operations Facility (LEOF).
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At about the same time, a Follow-up Report of Emergency to State and Local Govemments was being produced. This report routinely provides information including emergency classification, assistance requests, event description and PARS. This report was transmitted to offsite authorities by the State and Local Communicator beginning at 1233 hours0.0143 days <br />0.343 hours <br />0.00204 weeks <br />4.691565e-4 months <br />, and was completed at 1238 hours0.0143 days <br />0.344 hours <br />0.00205 weeks <br />4.71059e-4 months <br />.
Transmittal of the Report of Radiological Conditions to the State (MIDAS Run No. 6) was then initiated by the State and Local Communicator at 1245 hours0.0144 days <br />0.346 hours <br />0.00206 weeks <br />4.737225e-4 months <br /> and completed at 1250 hours0.0145 days <br />0.347 hours <br />0.00207 weeks <br />4.75625e-4 months <br />.
A review of the sequence of events indicates that while the process for report transmission may be enhanced, any delay in transmittal of the first report was not excessive. The time between availability of the printed report (1222 hours0.0141 days <br />0.339 hours <br />0.00202 weeks <br />4.64971e-4 months <br />) and the start of its transmittal to the State (1245 hours0.0144 days <br />0.346 hours <br />0.00206 weeks <br />4.737225e-4 months <br />) was 23 minutes. During this time, the Protective Action Recommendation in effect was verified to be bounding and the content of the report was reviewed and confirmed with key responders in the LEOF. It should be noted that the Bureau of Radiological Health representative in the LEOF is responsible for defining the radiological basis for Protective Action Decisions made by the State.
Regarding commitments to timeliness of notifications, Station Emergency Planning implementing Procedure (EPIP) -2.01,
" NOTIFICATION OF STATE AND LOCAL GOVERNMENTS" states, "[t]he initial Report of Radiological Conditions must be transmitted to the State EOC as soon as possible following the declaration of an emergency involving release of radioactive material and/or a General Emergency."
Further, EPIP-4.30, "USE OF MIDAS CLASS A MODEL," states, "(d]ose assessments are required within 15 minutes after a radiological release."
We have considered these requirements within the context of the actual sequence of events. Given report availability at about 1218 hours0.0141 days <br />0.338 hours <br />0.00201 weeks <br />4.63449e-4 months <br /> (1222 for printed results) and allowing time for reviews and message preparation, we find there is about a 10 minute period between completion of the process and the start of related communications to the State Emergency Operations Center (EOC). We do not deem this time excessive given concurrent, ongoing dialogue about the results between the Radiological Assessment Coordinator, Recovery Manager and on-scene State Bureau of Radiological Health representative.
IDENTIFIED ISSUE _t The exercise critique process revealed instances of user input errors.
Though unrelated to the transmittal of MIDAS Run No. 6 to offsite authorities, MIDAS Run Nos.
7 (time stamped 1223) and 8 (time stamped 1244) both reflected "enors made when inputting to the computerized dose projection model." Redundant dose assessment activities occurring in the Central EOF and in the Technical Support Center (TSC) identified these errors. As a result, personnelinitiated efforts to analyze the erroneous data, correct input parameters, and generate new calculations. Neither report was transmitted to the State EOC.
The nature of these errors indicates a need for an improved understanding of the dose assessment system's bases. This issue was discussed in the post-exercise critique Page 2 of 4
. and presented during the August 16, 1996 inspection exit meeting.
During that meeting, we indicated -that a Dose Assessment Review Task Team would be j
established. This effort has been initiated, and specific objectives of the team are:
to determine the cause of the input errors e
to assess the need to provide expanded MIDAS basis training to end users e
to identify previous dose assessment performance issues for applicability to assess the impact of past scenario implementation issues e
to identify. enhancements in MIDAS system-user interface, procedures and/or j
j training, and to develop an action plan to resolve issues and implement enhancements.
j-CONCLUSION:
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In summary, the basis for the exercise weakness, as stated in Inspection Report 50-338, 339/96-08 does not appear to accurately reflect activities conducted during the course of the emergency exercise. The inspection. report indicates 1:04 p.m. as the time radiological conditions were reported to offsite authorities. This would equate to 59 minutes from the release start time. Exercise documentation demonstrates this l
Information was communicated at 1245, about 19 minutes earlier.
We believe that a 40 minute interval from the start of the release to transmittal of the i
first Report of Radiological Conditions to the State is the correct duration. Further, we i
believe that this time frame is not excessive considering concurrent activities performed j
during this period. Nevertheless, we intend to investigate methods that will expedite transmittal of dose assessment results consistent with our procedural requirements of "as_soon as possible following the declaration of an emergency involving release of I
radioactive material."
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FIGURE 1 SEQUENCE OF EVENTS RELATED TO TRANSMITTAL OF RADIOLOGICAL DATA TIME EVENT 1205 Start of simulated radiological release 1206 General Emergency declared 1208 MIDAS 15-minute meteorological average posted to system file 1211 MIDAS Run #6 run time 1213 Report of Emergency, Message No. 8, notification start time 1216 Completed Report of Emergency, Message No. 8 (PAR transmitted to State) 1218 MIDAS Run #6 calculation completed 1220 to 1232 Radiological Assessment Coordinator evaluates and reviews information. Results reviewed with Recovery Manager, State BRH representatives in LEOF.
1221 Time dose calculation is required by EPIP-4.30 1222 MIDAS Run #6 system print 1223 MIDAS Run #7 run time 1233 Report of Emergency, Message No. 9, notification start time 1238 Completed Report of Emergency, Message No. 9 1244 MIDAS Run #8 run time 1245 Report of Radiological Conditions to the State, Message No.1, notification start time (transmits MIDAS Run No. 6) 1250 Completed Report of Radiological Conditions to the State, Message No.1 1255 MIDAS Run #9 run time 1345 Report of Radiological Conditions to the State, Message No. 2, notification start time (MIDAS Run No. 9) 1345 MIDAS Run #10 run time 1347 Completed Report of Radiological Conditions to the State, Message No.2 1423 MIDAS Run #11 run time Page 4 of 4
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