ML18153B466

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Responds to NRC Re Weaknesses Noted in Insp Repts 50-280/93-28 & 50-281/93-28 During Full Participation Exercise of 931208.Corrective Actions:Review & Developement Process for Exercise Scenarios Modified
ML18153B466
Person / Time
Site: Surry  Dominion icon.png
Issue date: 02/18/1994
From: Stewart W
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
94-031, 94-31, NUDOCS 9403030174
Download: ML18153B466 (5)


Text

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VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 February 18, 1994 United States Nuclear Regulatory Commission Serial No.94-031 Attention: Document Control Desk NEP/WFR/RPC w=a:sh:i~ng~t~on~,~D-::_*_~c':__. ~2~0~5~55-:___ ____ ~-----__c_---Doeket--Nos-. -50~200 50-281 License Nos. DPR-32 DPR-37 Gentlemen:

VIRGINIA ELECTRIC AND POWER* COMPANY SURRY POWER STATION UNITS 1 AND 2 RESPONSE TO NRC INSPECTION REPORT NOS. 50-280/93-28 AND 50-281/93-28 This is in reply to your letter of January 7, 1994, which transmitted the above referenced NRC Inspection Report.

That Inspection Report reflects an exercise weakness identified during the conduct of the Surry Power Station full participation Exercise of December 8, 1993.

Your letter requested information pertaining to corrective actions taken, or planned to be taken, as a result of the identified exercise weakness.

Pursuant to your request please find a summary of corrective actions provided as an attachment to this letter. The implementation of these corrective actions will preclude recurrence of the issue identified within the exercise weakness.

Should you have any questions, please contact us.

Very truly yours, J

W. L. Stewart Senior Vice President - Nuclear Attachment cc:

U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, N.W.

Suite 2900 Atlanta, Georgia 30323

. Mr. M. W. Branch NRC Senior Resident Inspector Surry Power Station Mr. A. E. Slayton, State Coordinator Virginia Department of Emergency Services 310 Turner Road Richmond, Virginia 23225-6491 9403030174 940218 PDR ' ADOCK 05000280 Q

PDR

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ATTACHMENT SURRY POWER STATION INSPECTION REPORT NOS. 50-280/93-28 AND 50-281/93-28 EXERCISE WEAKNESS 50-280, 281/93-28-01

SUMMARY

OF CORRECTIVE ACTIONS

SURRY POWER STATION INSPECTION REPORT NOS. 50-280/93-28 AND 50-281/93-28 EXERCISE WEAKNESS 50-280, 281/93-28-01

SUMMARY

OF CORRECTIVE ACTIONS NRC ASSESSMENT The provided basis for Exercise Weakness 50-280, 281/93-28-01 reads in part:

"... Following the release, the initial offsite dose projections by MIDAS indicated that PARs would be required beyond the 1 O mile plume pathway planning zone.

This information was immediately used to inform the Recovery Manager as well as an informal recommendation to the Commonwealth of Virginia DES personnel to evacuate the downwind sectors to 15 miles. The licensee's decision making process prior to making this recommendation did not use available guidance for correlating field team measurements to the dose projection nor did it consider any assumptions on which MIDAS was based that could account for the apparently excessive dose projection. The unofficial PAR to include distances to 15 miles* was hastily made without due consideration of the available data nor consideration of the perturbation such a PAR would have upon evacuating the personnel in the 1 O mile EPZ. The inspector identified the failure of LEOF decision makers to adequately evaluate the dose assessment data in formulating PARs as an EW [Exercise Weakness]."

ANALYSIS OF ISSUE While it is recognized that the conduct of any full participation exercise inherently produces results designed to drive offsite response actions, the radiological effluent data included within the scenario for the December 8, 1993 Exercise at Surry Power Station was such that it allowed the dose assessment model used by Virginia Power to project doses in excess of Protective Action Guidelines (PAGs) beyond the boundaries of the 10-mile Plume Exposure Pathway Emergency Planning Zone (EPZ). The assumptions along with default values included within the Meteorological Information and Dose Assessment System (MIDAS), coupled with the postulated accident sequence, resulted in the following identified issues:

1.

The exercise scenario development and review process did not identify the potential for MIDAS to produce doses in excess of PAGs beyond the 10-mile EPZ.

2.

The underlying bases used by MIDAS to formulate exercise dose projections in excess of PAGs beyond EPZ were not effectively communicated to utility or State decision-makers in the Local Emergency Operations Facility (LEOF) by dose assessment personnel.

Therefore, these underlying bases were not considered in the Protective Action Recommendation (PAR) decision making Page 1 of 3

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process. Bases include the specific assumptions and defaults that were actually used by MIDAS, the real time exercise scenario data not relied upon (i.e., safety valve steam flow rates), and the unavailability of confirmatory field data.

3.

The reasonableness of dose projections-in excess of PAGs beyond the EPZ during the exercise was not adequately questioned. For example, the expected core degradation associated with the postulated accident type was not fully considered by the responders within the context of the planning bases which establish the basis for the size of the 10-mile EPZ.

4.

Exercise dose projections prompted a decision to afford members of the public outside of the EPZ the same protection as those within the EPZ. This resulted in discussions within the LEOF with regard to expanding the existing PAR. EPIP 2.01, Notification of State and Local Governments, was not used to transmit the expanded PAR.

5.

Even if the accident type postulated within the exercise scenario had been of sufficient severity to produce doses in excess of PAGs beyond the 10-mile EPZ, decision makers failed to effectively coordinate their actions to expand response and protective actions beyond the 10-mile EPZ. For example, the discussion on implementation of this decision did not consider the potential

  • impact to evacuees that would be exiting the 10-mile EPZ.

CORRECTIVE ACTIONS TAKEN A Company working session was conducted on January 27, 1994 for persons holding Virginia Power Emergency Response Organization positions of Recovery Manager, Radiological Assessment Coordinator (RAC) or. Emergency Plan Advisor (EPA) for both Surry and North Anna power stations. Issues that contributed to the exercise weakness were reviewed, corrective actions were identified, and emergency response planning bases applicable to the above issues were reviewed during this session.

An interface meeting was subsequently held on February 9, 1994 with State representatives assigned to the LEOF (both, departments of Health and Emergency Services) and decision makers in the State Emergency Operations Center (EOC). The purpose of this meeting was to review the interface between response organizations and State processes which may affect the focus of the LEOF and to identify any interface issues in need of resolution. Specifically, this meeting reviewed issues that contributed to the exercise weakness, identified corrective actions, and reviewed applicable emergency response planning bases.

With respect to Issue No. 1, above, the review and development process for exercise scenarios has been modified to provide for an independent review of scenario radiological data. Corrective actions associated with Issue No. 1 are complete.

With respect to Issue No. 4, the corresponding corrective actions taken to date have served to reinforce that the formal method for PAR transmission to the State is through the process provided within EPIP-2.01, Notification of State and Local Governments.

Corrective actions associated with Issue No. 4 are complete.

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CORRECTIVE ACTIONS PLANNED An interface meeting held on February 9, 1994, between representatives of Virginia Power and the State, resulted in the decision to develop an interface document. This document will be used to identify pertinent agreements in the concept of operations between the two organizations and will reflect the application of the underlying planning bases. This action should be completed on or about May 1, 1994.

Corrective Action for Issue No. 2: Appropriate implementing procedures will be evaluated and modified as applicable to include guidance designed to encourage increased consideration of the technical basis for dose projections by decision makers within the LEOF. This action is scheduled to be completed by June 15, 1994.

Corrective Action for Issue No. 3: The interface document discussed above is intended to reflect the underlying emergency response planning bases for the concepts of operation associated with the Protective Action Recommendation process. This document will be provided to appropriate Emergency Response Organization members. This action is scheduled to be completed by June 15, 1994.

Corrective Action for Issue No. 5: Appropriate implementing procedures wili be modified to include guidance in the unlikely event of the need to provide protective actions beyond the planning basis, th~ 10-mile EPZ. The effect that protective actions beyond the 10-mile EPZ will have on protective actions within the 10-mile EPZ will be considered within the interface document. This action is scheduled to be completed by June 15, 1994.

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