ML20214K753
| ML20214K753 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 05/20/1987 |
| From: | Feigenbaum T PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| RTR-NUREG-0396, RTR-NUREG-396 NYN-87068, NUDOCS 8705290050 | |
| Download: ML20214K753 (9) | |
Text
PENHI May 20, M87 New Hampshire Yankee Division NYN-87068 i
United States Nuclear Regulatory Commission Washington, DC 20555 Attention:
Document Control Desk Refernees:
(a) Facility Operating License NPF-56, Construction Permit CPPR-1316, Docket Nos. 50-443 and 50-444 (b) USNRC Letter dated April 24,1987, " Transmission of NRC Staff Analysis of Dose as a Function of Distance for Design Bases Accidents at Seabrook Station", V. Nerses to R. J. Harrison.
Subject:
Comments on Staff Analysis of DBA-LOCA Dose as a Function of Distance Centlemen:
Enclosed are New Hampshire Yankee's (NilY) comments regarding the NRC Staff analysis of dose as a function of distance for design bases accidents at Seabrook Station as discussed with the NRC Staff at a meeting on May J
5, 1987.
If the Staf f has any questions or requires further clarification of these comments, do not hesitate to contact Mr. W. J. Daley, Jr., at (603) 474-9521, extension 2057.
Very truly yours, i
.(ph Ast T. C. Feigenbaum
)
0ochk43 8
PDR.
L '! \\l P.O. Box 300. Seabrook, NH 03874. Telephone (603) 474 9574
United States Nuclear Regulatory Commission NYN-87068 Attention: Document Control Desk Page 2 Enclosure cc:
Atomic Safety and Licensing Board Service List (Of fsite EP)
Mr. Victor Nerses, Acting Director Project Directorate I-3 Division of Projects I/II U. S. Nuclear Regulatory Commission Warhington, DC 20555 Mr. William T. Russell Regional Administrator U. S. Nuclear Regulatory Connission Region I 631 Park Avenue King of Prussia, PA 19406 Mr. A. C. Cerne NRC Senior Resident Inspector Seabrook Station Seabrook, NH 03874
ENCLOSURE TO NYN-87068 NHY COMMENTS ON THE STAFF ANALYSIS OF EMERGENCY PLANNING ZONE, DBA - LOCA
SUMMARY
At a meeting with the NRC Staf f on May 5,1987, New Hampshire Yankee provided detailed comments regarding the methodology and results of the staff analysis of design basis accident doses as a function of distance for Seabrook. In summary, two fundamental dif ferences between the method-ology utilized in the staf f analysis and that utilized by NHY were identified. They are as follows:
(1) The staf f utilized Seabrook site-specific five percent meteorology in lieu of the (r/ro)-1.5 extrapolation technique used in NUREG-0396 for determining doses vs distance.
(2) The staf f analysis thyroid dose was greater than the value determined by NHY at the exclusion area boundary as a re-sult of the iodine dose conversion f actors used.
Regardless of the fundamental differences between the methodologies used, the whole body upper Protective Action Guide (PAG) was not exceeded beyond one mile. However, the thyroid dose versus distance curve calculated by the NRC results in an upper PAG exceedence distance of 2.2 miles due to differences in analytical methodologies described above.
To proceed with resolution of criterion I to NUREG-0396, NRC decisions will be necessary regarding the specific acceptance criteria in deter-mining the Plume Emergency Planning Zone (PEPZ) for the DBA (e.g. upper PAG) including the definition of distance extrapolation techniques and dose conversion f actors to be utilized. The NRC should utilize the (r/ro)-1.5 extrapolation technique used by NUREG-0396, or consider the use of 50 percent site-specific meteorology which is more consistent with the methodology of NUREG-0396 in lieu of the 5 percent values. New thyroid PAGs based upon ICRP-26 should also be considered by the NRC in determining this acceptance criteria.
BACKGROUND One of the four criteria considered in NUREG-0396 (Reference 1) for deter-mining the size of the PEPZ was design basis accidents. To address this criterion for Seabrook, Reference 2 was prepared and submitted to the NRC in December 1986. Reference 2 used the dose results of the Design Basis Loss-Of-Coolant Accident (DBA-LOCA) as described in the Seabrook FSAR of 1.7 rem whole body and 77 rem thyroid at the exclusion area boundary.
These results were then extrapolated to greater distances using the methodology of NUREG-0396, i.e., (r/ro)-1.5 The results of these extra-polations were compared with Protective Action Guide (PAG) levels with the following results:
l a.
Whole body upper and lower PAG not exceeded beyond one mile.
)
ENCLOSURE TO NYN-87068 NHY COMMENTS ON Tile STAFF ANALYSIS OF EMERGENCY PLANNING ZONE, DBA - LOCA (Continued) b.
Thyroid upper PAG not exceeded beyond 1.2 miles.
Thyroid Lower PAG not exceeded beyond 3.5 miles.
c.
NUREG-0396 reported that approximately five percent of the units studied exceeded the whole body lower PAG for the DBA-LOCA and approx-imately 30 percent of the units exceeded the thyroid lower PAG. This report then went on to state "The study concluded that the higher PAG plume exposures of 25 rem (thyroid) and five rem (whole body) would not be exceeded beyond 10 miles for any site analyzed." Based on this, NHY I
concluded that the upper PAG 1evels can be considered an appropriate criteria for relating design basis accidents to the size of an EPZ.
Reference 2, therefore, used these upper PAGs in concluding that a PEPZ of approximately one mile was appropriate for Seabrook.
DETAILED DISCUSSION AND COMMENTS The NRC recently transmitted the results of their analysis of design basis accident doses as a function of distance for Seabrook (Reference 3).
The NRC used two distance extrapolation techniques - one based on (r/ro)-1.5 methodology used in NUREG-0396, and the second based on Seabrook site specific five percent meteorology. The first produced dose versus distance curves very similar to those reported in Reference 2 (see Refer-ence 3, Figures lA and IB). The extrapolation based on site specific meteorology produced curves with a somewhat higher dose for a given dis-tance. All of the whole body dose curves, however, showed that the upper PAG was not exceeded beyond one mile. The NRC site-specific thyroid dose curve showed that the upper PAG was not exceeded beyond 2.2 miles.
The basis for the (r/ro)-1.5 extrapolation is given as a 1970 EPA docume nt in Reference 1.
A more recent publication (NUREG/CR-2858, Ref-erence 4) suggests that the exponent 1.5 is appropriate for Pasquill D stability beyond 1000 meters. Stability Class D would be more represent-ative of 50 percent meteorology than the five percent values used by the NRC in their site-specific extrapolation.
NHY believes, therefore, that the use of five percent site-specific dispersion parameters represents a f undamental change f rom the methodology used in NUREG-0396 to determine the size of the PEPZ. The NRC should utilize the (r/ro)-1.5 method used by NUREG-0396 in determining the appropriate PEPZ distance for Seabrook or use 50 percent site-specific meteorology which is more consistent with the methodology of NUREG-0396.
The NRC DBA-LOCA thyroid dose reported in Reference 3 was 87 rem at the exclusion area boundary. We believe that the dif ference between this value, and the 77 rem reported by Seabrook in Reference 2 is due to the iodine dose conversion f actors used. It is our understanding that the NRC dose conversion factors came from TID-14844 (Reference 5) while the factors used by Seabrook came from NRC Regulatory Guide 1.109.
These f actors are -
ENCLOSURE TO NYN-87068 NHY COMMENTS ON THE STAFF ANALYSIS OF EMERGENCY PLANNING ZONE, DBA - LOCA (Continued) shown in the table below along with those f rom ICRP-30. Updating the TID-14844 values would result in a 15-20 percent reduction in thyroid dose.
Dose Conversion Factor, REM /CI Inhaled Iodine TID-14844 R. G. 1.109 ICRP-30 Isotope (1962)
(1977)
(1978) 131 1.48 + 6 1.49 + 6 1.08 + 6 132 5.35 + 4 1.4 3 + 4 6.44 + 3 133 4.00 + 5 2.69 + 5 1.80 + 5 134 2.50 + 4 3.73 + 3 1.07 + 3 135 1.24 + 5 5.60 + 4 3.13 + 4 The use of the PAG's recommended by EPA-520/1-75-001 (Reference 6) result in the thyroid dose being the limiting criteria for DBA-LOCA's.
This is due to the large conservatism built into the LOCA assumptions for iodine behavior, and the f act that the thyroid PAG's are only a f actor of five higher than those f or whole body exposure.
ICRP Publication 26 re-commends that organ doses be related to equivalent whole body doses by the use of weighting factors. The weighting f actor for the thyroid is 0.03.
The thyroid PAG's that would have the same risk as one and five rem whole body dose, would be 33 and 167 rem, respectively.
ICRP-26 also recommends a 50 rem limit for nonstochastic effects, however, which may limit the thyroid PAG's to 33 and 50 rem.
In January 1987, the NRC proposed a revision to 10CPR Part 20 which was, in part, based on ICRP-26 recommendations.
In the summary of that proposed rule, the NRC stated "The intent of the revision is to improve NRC radiation protection standards by reflecting developments in the prin-ciples that underlie radiation protection and advances in related sciences that have occurred since the promulgation of 10CFR20 nearly 30 years ago.
In particular, the revision would put into practice many of the more re-cent recommendations of the ICRP set forth in ICRP Publications 26, 30, and 32."
In November 1986, the ACRS sent a letter to the NRC (Reference 7) on the subject of protective action guides. This letter suggested that the NRC encourage the EPA to proceed with the timely development of new thyroid PAGs based on ICRP methodology. It also stated that the results of this development should be made available promptly for use in emergency planning evaluations. -
ENCLOSURE TO NYN-87068 NilY COMMENTS ON THE STAFF ANALYSIS OF EMERGENCY PLANNING ZONE, DBA - IqjA (Continued)
In January 1987, the president approved EPA recommendations for rad-iation protection guidance to federal agencies for occupational exposure (Reference 8). 'This guidance is based on the recommendation of-ICRP-26.
It is clear that in the future, organ doses will be ' limited based on the ICRP-26 weighting factors. Based on this, an upper thyroid PAG of 50 rem should be used for determining the size of a PEPZ. Even if the NRC LOCA result of 87 rem at the exclusion area boundary is used, and it. is extrapolated using Seabrook site specific five percent meteorology, a 50 rem PAG is reached at approximately one mile.
i 1
4 l l
ENCLOSURE TO NYN-87068 NHY COMMENTS ON THE STAFF ANALYSIS OF EMERGENCY PLANNING ZONE, DBA - LOCA (Continued)
REFERENCES 1.
" Planning Basis for the Development of State and Local Government Radiological Emergency Response Plans in Support of Light Water Nuclear Power Plants," NUREG-0396, December,1978.
2.
Lee, Shengdar:
Littlefield, Peter S.,
" Licensing Aspects of the Seabrook Eme rgency Planning Zone Study."
YAEC-1502, December 1985.
3.
Letter to Robert J. Harrison from Victor Nerses, " Transmission of NRC Staf f Analysis of Dose as a Function of Distance for Design Basis Accidents at Seabrook Station," April 24, 1987.
4.
Bande r, T. J., " PAVAN : An Atmospheric Dispersion Program for Evaluating Design Basis Accidental Releases of Radioactive Mater-tals f rom Nuclear Power Plants." NUREG/CR-2858, November 1982.
5.
DiNunno, J. J.; Anderson, F. D.; Baker, R. E.; Waterfield, R. L.,
" Calculation of Distance Factors for Power and Test Reactor Sites,"
TID-14844, March 23, 1962.
6.
" Manual of Protective Action Guides and Protective Actions for Nuclear Incidents." EPA-520/1-75-001, September, 1975.
7.
Letter to Lando W. Zech, Jr. f rom David A. Ward, " Protective Action Guides f or Nuclear Emergency Planning," November 10, 1986.
8.
Federal Register, Volume 52, No.17, January 27, 1987. - -
ASLB SERVICE LIST (OFF-SITE EP)
Helen Hoyt, Chairperson Carol S. Sneider, Esquire Atomic Safety and Licensing Board Panel Assistant Attorney General U.S. Nuclear Regulatory Commission Of fice of the Attorney General East West Towers Building One Ashburton Place, 19th Floor 4350 East West Highway Boston, MA 02108 Bethesda, MD 20814 Senator Cordon J. Humphrey*
Custave A. Linenberger, Jr.
United States Senate Atomic Safety and Licensing Board Panel Washington, DC 20510 U.S. Nuclear Regulatory Commission Attention: Tom Burack East West Towers Building 4350 East West Highway Richard A. Hampe, Esquire Bethesda., MD 20814 Hampe and McNicholas 35 Pleasant Street Dr. Jerry Harbour Concord, NH 03301 Atomie. Scfety and Licensing Board Panel U.S. Nuclear Regulatory Commission Thomas F. Powers, III East West rowers Building Town Manager 4350 East West Highway Town of Exeter Bethesda. MD 20814 10 Front Street Exeter, NH 03833 Diane Curran, Esquire Andrea C. Perster, Esquire Brentwood Board of Selectmen Harmon & Weiss RFD Dalton Road 2001 S Street, NW Brentwood, NH 03833 Suite 430 Washington, DC 20009 Peter S. Mathews, Mayor City Hall Sherwin E. Turk, Esquire Newburyport, MA 01950 Office of the Executive Legal Director U.S. Nuclear Regulatory Commission Calvin A. Canney Tenth Floor City Manager 7735 Old Georgetosm Road City Hall Bethesda, MD 20814 126 Daniel Street Portsmouth, NH 03801 Robert A. Backus, Esquire Backus, Meyer & Solomon Stephen E. Merrill, Esquire 116 Lowell Street Attorney General P.O. Box 516 George Dana Bisbee, Esquire Manchester, NH 03105 Assistant Attorney General Office of the Attorney General Philip Ahrens, Esquire 25 Capitol Street Assistant Attorney General Concord, NH 03301-6397 Office of The Attorney General Statehouse Station #6 Mr. J. P. Nadeau Augusta, ME 04333 Selectmen's Office 10 Central Road Mrs. Sandra Cavutis, Chairman Rye, NH 03870 Board of Selectmen RFD 1 - Box 1154 Kensington, NH 03827
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(Continued)
Mr. Angie Machiros, Chairman Charles P. Graham, Esquire Board of Selectmen McKay, Murphy and Graham Town of Newbury 100 Main Street Newbury, MA 01950 Amesbury, MA 01913 Mr. William S. Lord Board of Selectmen Town Hall - Friend Street Amesbury, MA 01913 Senator Cordon J. Humphrey*
1 Eagle Square, Suite 507 Concord, NH 03301 Attention: Herb Boynton H. Joseph Flynn, Esquire Office of General Counsel Federal Emergency Management Agency 500 C Street, SW Washington, DC 20472 Paul McEachern, Esquire Matthew T. Brock, Esquire Shaines & McEachern 25 Maplewood Avenue P.O. Box 360 Portsmouth, NH 03801 Gary W. Holmes, Esquire Holmes & Ells 47 Winnacunnet Road Hampton, NH 03842 Mr. Edward A. Thomas FEMA, Region I 442 John W. McCormack Post Office and Courthouse Boston, MA 02109 Robert Carrigg Town Office Atlantic Avenue North Hampton, NH 03862 Judith H. Mizner*
Silvergate, Gertner, Baker, Fine, Good & Mizner 88 Broad Street Boston, MA 02110
(
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