NUREG-1210, Testimony of Tj Mckenna Re NUREG-1210.* Related Correspondence

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Testimony of Tj Mckenna Re NUREG-1210.* Related Correspondence
ML20196G726
Person / Time
Site: Seabrook  NextEra Energy icon.png
Issue date: 06/24/1988
From: Mckenna T
NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD)
To:
Shared Package
ML20196G717 List:
References
RTR-NUREG-1210 OL, NUDOCS 8807060018
Download: ML20196G726 (8)


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  • ' 00CKETED USNRC UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION 10 JUN 30 P2 :29 BEFORE THE ATOMIC SAFETY AND LICENSING BOARD {f g y '-; }{; g nawa In the Matter of Docket Nos. 50-443 OL PUPLIC SERVICE COMPANY OF 50-444 OL NEW HAMPSHIRE, et al. Off-site Emergency Planning (Seabrook Station, Units 1 and 9)

TESTIMONY OF THOMAS J. McKENNA CONCER][ING NUREG-1210

'Q1. Plcese state your name and by whom you are employed.

A1. F'y name is Thomas J. McKenna. I am the Section Leader of the Program Section of the Incident Response Branch, Division of Operational Assessment, Office for Analysis and Evaluation of Operational Data, U. S.

Nuclear Regulatory Commission.

4 02'. Ple6se describe your current responsibilities.

AP. I have responsibility for the development and implementation of procedures to be utilized by hRC personn=I who respond to severe reactor accidents in assessing the adequacy of protective action recomnendations for the public. This includes the development of training materials, the development of technical tools and procedures, and providing training to a wide range of individuals and groups including the Commissioners of the f!uclear Regulatory Commission. In addition, I am responsible for the development of a standardized respense training program to include training on severe accident assessment, response management, and coordination with other Federal agencies. I also manage the development 8807060018 880624 PDR ADOCK 05000443 O PDR

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end implementation of the procedures for activation of the NRC response organization, the program to assure a consistent and adequate regional response program, and the exchange of response information within and outside the United States. I am also responsible for coordinating NRC Headquarters participation in emergency drills and exercises.

Q3. Are you familiar with a 5-volume document entitled "Pilot Frcgrun: NRC Severe Reactor Accident Incident Response Training Manual",

NUREG-1210 (February 1987)?

A3. Yes. NUREG-1210 is a training manual, which essentially consists of a compilation of material that was developed for use in training hRC incident response personnel.

Q4. Please describe your past and present responsibilities with respect,to the formulation cod use of NUPEG-1210.

A4. NUREG-l?10 compiles the training material that was developed and presented by me and other NRC personnel in my section over the past few years. I served as project manager for the development of this docun.ent, and was one of its principal authors. NUPEG-1210 refects our best understanding of severe reactor accidents as they relate to the NRC's responsibilities for protecting the public health and safety in the event thot such an accident should occur. I have used or have supervised the use of this document in presenting numerous courses to a wide range of students. I have presented this material to the current and previous NRC Chairman, each of the other Conmissioners, the NRC Regional

o Administrators, Senior NRC Management, members of the NRC staff, other Federal agencies, as well as numerous State and local officals around the country. These manuals have also been the basis for NRC presentations and course material distributed at various FEMA courses on reactor accident assessment.

Q5. Please describe the basic philosophy of NilREG-1210.

AS. The basic premise inherent in NUREG-1210 is that in the unlikely event of a severe-core damaging event or conditions that predict such an event, uncertainies remain as to whether a release will occur, the size of any such release, the source term, the duration of the release, or its censequences. NUREG-1210 considers these uncertainties, and recognizes that sheltering in most structures close to a nuclear plant (i.e., within 2-3 miles), where plume concentration and dose consequences are likely to be highest, will r.ot be effective in preventing early health effects given a major rele6se. Accordingly, NUREG-1210 concludes that generally it is better to evacuate near the plant promptly rather than wait for such additional ir. formation which may becone availab1c upon the occurrence of a release. In general, early evacuation of the areas near a plant, conmenced on the basis of in-plant information, provides the best assurance that early health effects will be prevented cr rinimized in the event of a severe reactor accident.

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? Q6. Please explain the following statement which appears on page 19 of NUREG-1210, Volume 4: "At most U.S. nuclear reactor sites, fewer than 300 people live within the first 2 to 3 miles around the plant."

A6. The basic, simple protective action scheme of evacuation close-in to a reactor in the event of a severe accident, was intended for use at all sites, including sites with high population density. From experience, however, the authors recognf7ed that many emergency responders might have difficulty accepting a recomendation that there be a precautionary evacuation, before it is known whether a release will occur, even in the event of a severe-core damaging event. For this reason, the authors included this statement in NUREG-1210, to indicate that at most sites in the U.S. it should not be difficult to implement a precautionary evacuation. However, the staterrent was not intend 9d to limit the basic protective action concepts in NUREG-1210 to only those sites which have a low population density in areas close to the plant. We attempted to make this clear by inserting the statement which follows this, at page 19 of volume 4: "It trust always be remembered, though, that (1) for all sites, early evacuation of nearby areas would be most beneficial and (2) for the most severe accidents, early evacuation would be the only protective action available to achieve basic radiation protection objectives near the plant" (emphasis in original).

Q7. Please explain the statements which appear on pages 19-20 of NUREG-1210, Volume 4, as follows:

Early sheltering appears to be an appropriate protective action measure . . .

3 3. if severe entrapment problems are likely to

-occur if an evacuation is attempted, . . . or

5. where a large population density makes entraprrent outside very likely.

A7. Unfortunately, these statements have caused some confusion due to a lack of clarity in the authors' intent. For a proper interpretation of these statements, it is important to put them in context. In Sectior 3.1, we attempted to make it clear that evacuation of the area close-to the plant was the apprcpriate predetermined protective action for severe eccidents, with one exception as stated at the top of page 19: "The only exception to this, as stated previously, is under severe entrapment condi-tions (e.g., a snow or ice storm because a car is not as good a shelter as ahouse)." Item 3, quoted here in Question 7. refers to conditions where it is not practical to move the people who are close to the plant. Here, we were atteropting to remind the NRC response personnel that there may be

" ra re'I ponditions that prevent evacuation. However, as stated on page 19, "for the trost severe accidents, early evacuation would be the only protective action available to achieve basic radiation protection objectives near the plant."

The reference to "a large population density" which "makes entrapment outside very likely," was intended to apply to the entire plume exposure pathway EPZ and not just the areas near a plant. The authors of this statement had in mind large cities beyond 2-3 miles from the plant with substantial buildings made of steel and concrete which would afford

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' ? relatively good sheltering. The authors' inclusion of this statement was only intended to indicate that for such areas, the combination of a large population dersity and the availability of good shelters might warrant a recomitendation of early sheltering instead of early evacuation.

Finally, NUREG-1210 indicates that emergency responders should take such factors as high population density into consideration in recommending a protective action. For instance, where areas close to a plant are characterized by a high perulation density, it may be important to postpone evacuation of persons located further away from the plant in order to permit as prompt an evacuation as possible for persons at greater risk, close-in to the plant. Fnrthisreason,NUREG-1210 states"[t.lhe energency planner (and responder) must reccgnize that evacuation would be noredifficultattheselatter(highpcpulationdensity) sites,and contingency plans trust he prepared and decisions made accordingly in the planning process. It must always be remembered, though, that (1) for all sites, early evacuation of nearby areas would be rnost beneficial and (2) for the cost severe accidents, early evacuation would be the only protective action available to achieve basic radiation protection objectives near the plant.

QC, Assuming that a site was characterized by high population density within 2-3 miles from a nuclear plant, with a potential for evacuation traffic congestion lasting many hours, would that constitute "cntrapment" within the meaning of NUREG-12107

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. A8. An argument can be made that the term "entrapment" embraces such a situation, although the authors of NUREG-1210 did not and do not consider that this type of situation warrants a departure from the basic philosophy that close-in areas should be evacuated early based upon in-plant conditions. In essence, only where an evacuation is impossible for as long as 12 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (such as in a severe snow or ice storm, bridge outage, etc.), shculd shelter be considered as an alternative to evacuation for areas close to the plant. However, it should be noted that for very severe accidents, shelter is unlikely to prevent early health effects and, as pointed out on page 18 of volume 4, in those situations it is more important that "emergency personnel shculd monitor for ground coritaminatien following a release, if any, and motivate people to leave any areas found to contain large amounts of contamination (i.e., hot spots)."

finally,itshculdberecognizedthatplanningwhichreliescr.

sholtering as the protective action for populations close to a plant (i.e., 2-3 miles), would cause any evacuation of those persons to be delayed even for those accidents where an evecuation could be completed before a release. The fundarrental problem wf th such an approach is that at'the tirro an accident is first detected (based on plant conditions), it will be very difficult to predict whether or when a release will take place or to characterize correctly the characteristics of the release.

Due to the large uncertainties which will exist during a core melt accident as to accident progression and the likelihood, nature and duration of a potential release, it is important that once severe accident 1

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8-conditions are detected in the plant (e.g., core damage), action should be taken invrediately to prevent or reduce early health effects; close to the plant, this warrants an evacuation.

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