ML19340F178
| ML19340F178 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 12/17/1980 |
| From: | Crutchfield D Office of Nuclear Reactor Regulation |
| To: | Hoffman D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| Shared Package | |
| ML19340F179 | List: |
| References | |
| TASK-02-02.A, TASK-2-2.A, TASK-RR LSO5-80-12-039, LSO5-80-12-39, NUDOCS 8101210229 | |
| Download: ML19340F178 (7) | |
Text
C sneer f,,
UNITED STATES q
y e(
g NUCLEAR REGULATORY COMMISSION b
~
g.k' "'[' f E
WASHINGTON, D. C. 20555 s
e, o,,
nra 1 '7 *CP.
GS Zi, y
=
g R
75 Docket No. 50-155 LS05-80-12-039 0
ES oo Mr. David P. Hoffman Nuclear Licensing Administrator Consumers Power Corpany 212 West Michigan Avenue Jackson, Michigan 49201
Dear Mr. Hoffman:
SUBJECT:
BIG ROCK POINT - SEP TOPIC II-2.A, SEVERE WEATHER PHENOMENA The SEP review of Topic II-2.A, " Severe Weather Phenomena" has been completed. is the staff's safety evaluation (SE) for the Big Rock Point site.
The review was done in conformance with Standard Review Plan 2.3.1 and covers extreme temperatures, lightning strikes, snow and ice loads and wind and tornado loadings. The wind and tornado loadings analysis was performed by the Texas Tech. University, Institute for Disaster Research. Enclosure 2 is the Texas Tech. report. Please inform us if your as-built facility differs from the licensing basis assumed in our assessment within 30 days of receipt of this letter.
of 10'}l note that the SE identifies a design basis tornado with a probability You wi per year and is consistent with a Regulatory Guide 1.76 design basis tornado. The staff intends to evaluate the structural characteristics of specific structures, systems and components important to safety to determine thcir ability to withstand the severe weather loadings. The plant design parameters will then be compared to the probability of occurrence of the wind as a part of our structural evaluation. This comparison will be used to evaluate the necessity of design changes.
Sincerely, 7g.i Dennis M. Crutch ield, hie Operating Reactors Branch #5 Division of Licensing
Enclosure:
As stated l
cc w/ enclosure:
See next page 8103220129
I Mr. David P. Hoffman BIG ROCK POINT DOCKET NO. 50-155 CC Mr. Paul A. Perry, Secretary U. S. Environmental Protection 4
Consumers Power Co@any Agency 212 West Michigan Avenue Federal Activities Branch Jackson, Michigan 49201 Region V Office ATTN: EIS C0ORDINATOR i
Judd L. Bacon, Esquire 230 South Dearborn Street Consumers Power Company Chicago, Illinois 60604 212 West Michigan Avenue Jackson, Michigan 49201 Herbert Grossman, Esq., Chairman Atomic Safety and Licensing Board Joseph Gallo, Esquire U. S. Nuclear Regulatcry Comission Isham, Lincoln & Beale Washington, D. C.
.,,5 5 5 1120 Connecticut Avenue Room 325 Dr. Oscar H. Paris Washington, D. C.
20036 Atomic Safety and Licensing Board V. S. Nuclear Regulatory Comission Peter W. Steketee, Esquire Washington, D. C.
20555 505 Peoples Building Grand Rapids, Michigan 49503 Mr. Frederick J. Shon Atomic Safety and Licensing Board Alan S. Rosenthal, Esq., Chairman U. S. Nuclear Regulatory Comission Atomic Safety & Licensing Appeal Board Washington, D. C.
20555 U. S. Nuclear Regulatory Comission Washington, D. C.
20555 Big Rock Point Nuclear Power Plant ATTN: Mr. C. J. Hartman Mr. John O'Neill,11 Plant Superintendent Route 2, Box 44 Charlevoix, Michigan 49720 Maple City, Michigan 49664 Chris ta-Mari a Charlevoix Public Library Route 2, Box 108C 107 Clinton Street Charlevoix, Michigan 49720 Charlevoix, Michigan William J. Scanlon, Esquire Chairman 2034 Pauline Boulevard County Board of Supervisors Ann Arbor, Michigan 48103 Charlevoix County Charlevoix, Michigan 49720 Resident Inspector Big Rock Point Plant Office of the Governor (2) c/o U.S. NRC Room 1 - Capitol Building RR 73, Box 600 Lansing, Michigan 48913 Charlevoix, Michigan 49720 Director, Technical Assessment Mr. Jim E. Mills Division Route 2, Box 108C Office of Radiation Programs Charlevoix, Michigan 49720 (AW-459)
U. S. Environmental Protection Thomas S. Moore Agency Atomic Safety & Liceasing Appeal Board Crystal Mall #2 U. S. Nuclear Regulctory Comission Arlington, Virginia 20460 Washington, D. C.
20555 1
ENCLOSURE 1 i
Systematic Evaluation Program Meteorology Big Rock Point Nuclear Plant Topic II-2.A Severe Weather Phenomena I
Extreme metecrological conditions and severe weather phenomena in the Big Rock Point site region were examined to determine if safety-related structures, systems, and components are designed to function under all severe weather conditions. Discussed below are the severe weather phenomena which could adversely affect the Big Rock Point site and which should be examined relative to the current design.
Normal daily temperatures range from a minimum of 10 degrees Fahrenheit in January to a maximum of 80 degrees Fahrenheit in July. Measured' extreme temperatures for the site region are 103 degrees Fahrenheit and
-37 degrees Fahrenheit. The extreme maximum and minimum temperatures appropriate at the Big Rock Point site for general plant design (i.e.,
HVAC systems) are 86 degrees Fahrenheit (equalled or exceeded 1% of the time) and -6 degrees Fahrenheit (equalled or exceeded 99% of the time).
(
Thunderstorms occur an average of 32 days per year in the site region.
l Based on the annual number of thunderstorm days, the calculated annual flash density of grount lightning strikes is four flashes per square kilometer. A structure with the approximate dimensions of the Big Rock l
o.
i Point reactor building can be expected to be subjected, on the average, to one strike every seven years.
The design wind speed (defined as the " fastest-mile" wind speed at a t
height of 30 feet above ground level with a return period of 100 years) acceptable for the site region is 80 miles per hour. On the average, hail storms occur about two days annually, and, freezing rain occurs approximately 12 days per year.
The maximum radial thickness of ice expected in the site region is about 0.75 inch.
Mean annual snowfall in the site region is approximately 100 inches.
Data for the maximum monthly snowfall, the maximum snowfall from a single storm, and the maximum. measured snow depth on the ground for the site region is not readily available.
Based on the 100-year recurrence accumul'ated ground snowpack and probable maximum winter precipitation for the site region, the normal winter precipitation snow load on a flat 9=*
surface is about 50 pounds per sqt are foot and the extreme winter pre-cipitation snow load on a flat surface is 115 pounds per square foot.
Tornadoes have been reported 25 times during the period 1950-1977 within an approximate 60-mile radius from the Big Rock Point site, excluding the water area over Lake Michigan. On the average, one tornado can be expected to occur in the vicinity of the Big Rock Point site every year.
Based on the tornado characteristics for the site region and the proba-bility calculations outlined in HASH-13,00, the recurrence interval for a l
tornado at the site is calculated to be about 5150 years.
The assumptions used in Regulatory Guide 1.76 provide an adequate design basis tornado for the site region. These characteristics include a maximum windspeed of 360 miles per hour (a maximum rotational windspeed of 290 miles per hour plus a maximum translational windspeed of 70 miles per hour), a maxinum pressure drop of three pounds per square inch, and rate of pressure drop of two pounds per square inch per second.
Based on actual tornado occurrences in the site region area and using the proedures discussed in WASH-1300, a " site-specific" design basis tornado (with a probability of occurrence of 10-7 per year) can be calculated.
For the Big Rock Point site, the characteristics of tornadoes occurring with-4 in a 60-mile radius are a maximum windspeed of 310 miles per hour (a maximum rotational windspeed of 250 =iles per hour plus a maximum trans-lational windspeed of 60 miles per hour), a maximum pressure drop of two pounds per square inch, and rate of pressure drop of one pound per square inch per second. Because of the infrequent occurrence of tornadoes in the site region (19 tornadoes with available data), the site-specific tornado characteristics are based on a very small sample of data which we believe does not provide a reasonable degree of accuracy for calculations of safety-related structure design.
'i t
I t
l.
References U.S. Department of Commerce, NOAA, " Climates of the States," Vol.1, 1974.
U.S. Department of Commerce, " Climatic Atlas of the United States "
June 1968.
U.S. Department of Commerce, NOAA, " Climates of the United States,"
1973.
H. C. S. Thom, "New Distributions of Extreme Winds in the United States "
Journal of the Structural Division ASCE, Vol. 94, No. ST7, July 1968.
"American National Standard Building Code Requirements for Minimum Design Loads in Buildings and Other Struc'.ures," ANSI, A58.1-1972.
" Seasonal Variation of the Probable Maximum Precipitation East of the 105th Meridian for Areas from 10 to 1,000 Square Miles and Durations of 6,12, 24, and 48 Hours," Hydrometeorological Report No. 33, Washington, D. C., April 1956.
James A. Ruffner and Frank E. Baier, "The Weather Almanac," Gale Research Cocpany,1974.
David M. Ludlum, " Weather Record Book," Weatherwise, Inc.,1973.
J. L. Marshall, " Lightning Protection," John Wiley and Sons, New York, 1973.
~
"ASHRAE Handbook of Fundamentals," American Society of Heating, Refrigeration,ind Air Conditioning Engineers, Inc., New York 1976.
Paul Tattleman and Irving I. Gringorten, " Estimated Glaze Ice and Wind Loads at the Earth's Surface for the Contiguous United States,"
Air Force Camtridge Research Laboratories, October 1973.
U.S. Housing and Hoce Finance Agency, " Snow Load Studies," Housing Research Paper No.19, May 1952.
U.S. Naval Weather Service, "World-Wide Airfield Summaries," Vol. VIII, United States of America, Part 4,1969.
Memo from Harold R. Denton (Assistant Director for Site Safety, Division of Technical Review, NRR) to R. R. Maccary (Assistant Director for Engineering, Division of Technical Review, NRR) dated March 24, 1975,
Subject:
Site Analysis Branch Position - Winter Precipitation Loads.
l l.
Memo from Jerry Harbour (Chief. Site Safety Research Branch, Division of Reactor Safety Research, RES) to L. G. Hulman (Chief. Hydrology-Meteorology Branch, Division of Site Safety and Ervironmental Analysis, NRR) dated August 14, 1978,
Subject:
Tornado Frequency Data for SEP Review.
Regulatory Guide 1.76, " Design Basis Tornado for Nuclear Power Plants,"
U.S. Nuclear Regulatory Comission, Washington, D.C.
g WASH-1300, " Technical Basis for Interim Regional Tornado Criteria,"
U.S. Atomic Energy Comission, May 1974.
H. C. S. Thom, " Tornado Probabilities," Monthly Weather Review, October-December 1963, pp. 730-736.
1
.--