ML20112C733
| ML20112C733 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 12/18/1984 |
| From: | Eisenhut D Office of Nuclear Reactor Regulation |
| To: | BOSTON EDISON CO. |
| Shared Package | |
| ML20112C735 | List: |
| References | |
| NUDOCS 8501110362 | |
| Download: ML20112C733 (5) | |
Text
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ENCLOSURE l' UNITED STATES'0F AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of Docket No. 50-293 BOSTON EDISON COMPANY (Pilgrin t'uclear Power Station)
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EXEMPTION I.
The Boston Edison Company (BEC0/the licensee) is the holder of
' Facility Operating License No. DPR-35 which authorizes operation of the Pilgrim Nuclear Power Station. This license provides, among other things, that it'is subject to all rules, regulations and Orders of the Commission new or hereafter in effect.
The facility comprises one boiling water reactor at the licensee's site located in Plymouth County, Massachusetts.
II.
On November 19, 1980, the Commission published a revised Section 10 CFR 50.48 and a new Appendix R to 10 CFR 50 regarding fire protection features of nuclear power plants (45 FR 76602). The revised Section 50.48 m f.ppendix f; I " carn ef fective on Frk rua ry 17, ? f f 1.
Sectior. !TI of Appendix R contains fifteen subsections, lettered A through 0, each of which specifies rcouirements for a particular asrcct of the fire protection
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.- Subsection III.G.2 of Appendix R requires that one train of cables ~and equipment necessary to achieve and maintain safe shutdown shall be maintained free of fire damage by specific use of fire barriers, separation or enclosures.
If these. conditions are not met,Section III.G.3 requires an alternative shutdown capability independent of the fire area of cCncern.
III.
By letter dated May 17, 1983, the licensee requested the following exemptions from the requirements of Sections III.G.2 and III.G.3 of Appendix R:
1.
Exemptions for Fire Zones 1.9 and 1.10 on the 23-foot elevation and Fire Zones 1.Il and 1.12 on the 51-foot elevation of the reactor building were requested to the extent Section III.G.2 requires a total area coverage automatic fire suppression system and 20 feet of separation free of intervening combustibles between redundant trains of safe shutdown equipment and cabling.
Exemptions for the same fire zones were also requested from the requirement in Section III.G.3 to have fixed fire suppression systems in areas with alternative shutdown capability.
Fire 7enes 1.9 and 1.11 contain the train "A" sFutdown ccrponents and Fire Zones 1.10 end 1.12 contain the train "B" shutdown corponents.
The horizontal separation between these redundant trains is greater
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The licensee
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. f proposes to. install automatic water curtains where physical barriers do not exist between the fire zones on each elevation. All of these
' zones have smoke detectors which alarm in the control room and redundant cables have been installed outside the fire zones to provide alternative shutdown capability.
Based on our review of the existing' fire protection features and
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the proposed modifications, we find that there is reasonable assurance that one division of shutdown equipment would remain free of fire damage to achieve and maintain safe shutdown.
'2.
An exemption for Fire Zone 1.30A (the torus compartment) was requested from the Section III.G.2 requirement to install fire detection and automatic fire suppression systems. The licensee-justifies the exemption on the following bases:
(1) the in-situ. fuel loading is very low; (2) the area has limited access during normal operation; (3) the redundant trains of shutdown equipment are horizontally separated by 30 feet free of intervening combustibles; and (4) one train of redundant cables is enclosed in a one-hour fire rated barrier.
Considering the bases stated above, we concluded that fires involving combustibles in the torus compartment would be so limited in size and duration that the proposed one-hour fire rated barrier would provide adequete protection for one train of safe shutdor.n cables.
Furthernore, because of the torus configuration, full area fire detection and autenatic suppression would not provide a sianificant wcyc n r in 'i,
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An exemption was requested for Fire Zone 3.5 (the Vital M.G. set room) from Section III.G.3 to the extent it requires a fixed fire suppression system in an area for which alternate shutdown capability is provided. This fire zone is separated from other areas by three-hour rated fire barr'iers and its combustible loading is noderate. A fire detection system and manual suppression equipment are available in the area. We find that there is reasonable assurance that fire in this area would be promptly detected and extinguished.
Thus, the installation of a fixed fire suppression system would not significantly increase the level of fire protection in this area.
As a result of our review, we conclu 'ed that the existing fire protection, together with the proposed modifications, in Fire Zones 1.9, 1.10, 1.11, 1.12, 1.30A and 3.5 provides a level of fire protection equivalent'to compliance with the technical requirements of Sections III.G.2 and III.G.3.
Therefore, the requested exemptions should be granted.
IV.
Accordingly, the Commission has determined that, pursuant to 10 CFR 50.12(a), the requested exemptions are authorized by law and will not endanger life or property or the common defense and security and are otherv;ite in tha public interest.
Therefore, the Commist. inn hoceby crants the following exemptions from the requirements of Sections !!I.G. of fppendix R to 10 CFR Part 50:
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Fire Zones 1.9, 1.10, 1.11, and 1.12 to the extent they require total area coverage automatic fire suppression systems and 20 feet of separation free of intervening combustibles between redundant trains of safe shutdown equipment and cabling.
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Fire Zone 1.30A to the extent it requires the installation of fire detection and automatic' fire suppression systems.
3.
Fire Zones 1.9, 1.10, 1.11, 1.12, and 3.5 to the extent they require fixed fire suppression systems in areas with alternative shutdown capability.
Pursuant to 10 CFR 51.32, the Commission has determined that the granting of these exemptions will have no significant impact on the y
environment (49 FR 47342).
A copy of the Safety Evaluation dated December 18, 1984, related to this action is available for public inspection at the Commission's Public Document Room, 1717 H Street, N. W., Washington, D. C. and at the local public docunent room located at the Plymouth Public Library, florth Street, Plynouth, Massachusetts.
A copy may be obtained upon request addressed to the 11. S. Nuclear Regulatory Commission, Washington, D. C. 20555, Attention:
Director, Division of Licensing.
This Exenption is effective upon issuance.
FOP Tl!E fillCLEMI tre iLn?0RY CP"mS5inti
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VI iarre 1 G. Ei senhut, Di ctor' Oivision of 'iconsina o ~iu er l'uclotr rn, m L W
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this 18th day of December, 1984 t
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