ML20073C581
| ML20073C581 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 03/30/1983 |
| From: | Jackie Cook CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20073C593 | List: |
| References | |
| 21567, NUDOCS 8304130228 | |
| Download: ML20073C581 (3) | |
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Consumels Power James W Cook Vice President - Projects, Engineering and Construction General offices: 1945 West Pernall Road, Jackson, MI 49201 e (517) 78&o453 March 30, 1983 Harold R Denton, Director Office of Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 MIDLAND NUCLEAR C0 GENERATION PLANT MIDLAND DOCKET NOS 50-329, 50-330 SEISMIC MARGIN REVIEW REPORT FILE: B3.7.1 SERIAL:
21567 ENCLOSURE: VOLUME II - REACTOR CONTAINMENT BUILDING (25 COPIES)
REFERENCE:
LETTER FROM J W COOK TO H R DENTON, SERIAL 21010 DATED FEBRUARY 4, 1983 As an attachment to our letter, Serial 21C?0, dated February 4,1983, we submitted the criteria for the Seismic Margin Review, Volume I, for the Staff's review and it was subsequently discussed in a meeting on February 8, 1983 in Bethesda. The firm of Structural Mechanics Associates (SMA) of Newport Beach, CA, under the direction of Dr. R P Kennedy was entrusted the e
task of performing the Seismic Margin Review per the criteria in Volume I.
Volume II, dealing with the evaluation of the seismic margins in the Reactor Containment Building, is submitted for the Staff's review as an attachment to this letter.
Volume II of the Seismic Margin Review report titled, " Reactor Containment Building" describes in detail the method of analysis and the resulting seismic margins. The Staff requested us to consider concurrent effects of pressure due to a small break LOCA event along with the seismic margin earthquake in evaluating the margins of the reactor containment building. However, the criteria for establishing the characteristics of a small break LOCA is not yet Therefore, a very conservative approach was chosen by assuming o g f well defined.
concurrent occurrence of full design basis accident pressure (70 psig) along D
with the seismic margin earthquake. Furthermore, as an additional source of I
conservatism, the maximum design accident temperature due to a design basis f
LOCA was also included as part of the loading combination.
In spite of all of
] P the above mentioned conservatism, the evaluation shows that there is still considerable amount of margin in the design. The lowest margin identified for the containment shell and basemat was conservatively estimated at 1.50 with respect to code allowables. For the internal concrete structures lowest oc0383-0385a100 8304130228 830330 PDR ADOCK 05000329 A
PDR i
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l margin was conservatively estimated as being 1.60 with respect to code allowables.
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Future volumes of the Seismic Margin Review report dealing with structures and systems will be submitted as they become available.
JWC/BFH/dlm CC RJCook, Midland Resident Inspector RHernan, US NRC (3)
FRinaldi, NRC GHarstead, Harstead Engineering l
oc0383-0385a100
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CONSUMERS POWER COMPANY Midland Units 1 and 2 Docket No 50-329, 50-330 Letter Seria121567 Dated March 30, 1983 At the request of the Commission and pursuant to the Atomic Energy Act of 1954, and the Energy Reorganization Act of 1974,'as amended and the Commission's Rules and Regulations thereunder, Consumers Power Company submits Volume II of the Seismic Margin Review Report.
CONSUMERS - ER COMPANY By
/
J Cook, Vice President '^
Proj e s, Engineering and Constraccion Sworn and subscribed before me this [
day of d 2 ///j.
f GattL Beverly A. AvyY Notary Pu61ic Jackson County, Michigan My Commission Expires
// ///d' f
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