[Federal Register Volume 62, Number 160 (Tuesday, August 19, 1997)]
[Notices]
[Pages 44153-44154]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-21896]
[[Page 44153]]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-271]
In the Matter of Vermont Yankee Nuclear Power Corporation
(Vermont Yankee Nuclear Power Station); Exemption
I
The Vermont Yankee Nuclear Power Corporation (VYNPC, the licensee)
is the holder of Facility Operating License No. DPR-28, which
authorizes operation of the Vermont Yankee Nuclear Power Station (the
facility) at power levels no greater than 1593 megawatts thermal. The
facility is a single-unit boiling-water reactor located at the
licensee's site in Windham County, Vermont.
The License provides, among other things, that the Vermont Yankee
Nuclear Power Station is subject to all rules, regulations, and orders
of the Nuclear Regulatory Commission (the Commission) now or hereafter
in effect.
II
On November 19, 1980, the Commission published a revised Section 10
CFR 50.48 and a new Appendix R to 10 CFR Part 50 regarding fire
protection features of nuclear power plants. The revised Section 50.48
and Appendix R became effective on February 17, 1981. Section III of
Appendix R contains 15 subsections, lettered A through O, each of which
specifies requirements for a particular aspect of the fire protection
features at a nuclear power plant.
Sections III.G and III.L are the subject of the licensee's
exemption request. Section III.G.3 specifies that fire detection and
suppression be installed in areas using alternative safe shutdown. Low
fire loadings and fire paths clear of combustibles in fire zones RB-1,
RB-2, RB-3, and RB-4 diminish the importance of full fire detection and
suppression capability in these fire zones. Section III.L.1.(c)
requires that alternative and dedicated shutdown capability be able to
achieve and maintain hot shutdown. Use of the automatic
depressurization system (ADS), which is proposed by the licensee,
requires cooling below hot shutdown temperatures, contrary to Section
III.L.1.(c). Section III.L.2.b requires that coolant level be
maintained above the top of the core, which is not possible with the
licensee's proposed use of the ADS and low pressure injection systems
(either core spray [CS] or low-pressure injection system) to achieve
and maintain hot shutdown.
The licensee requested an exemption from these requirements to
allow the use of the ADS in conjunction with low-pressure injection
systems as a means of achieving post-fire safe-shutdown conditions in
fire zones RB-1, RB-2, RB-3, and RB-4 when offsite power is not
available.
Section III.L.3 requires that alternative shutdown capability
accommodate conditions where offsite power is not available for 72
hours. Onsite power can be restored to service in 30 minutes. Two
offsite power sources exist in addition to the Vernon tie-line, which
can be placed in service in 10 minutes. Without the Vernon tie-line,
which is actually off site, the plant cannot accommodate conditions in
the first 30 minutes following loss of offsite power.
The licensee requested an exemption to allow the use of the Vernon
tie-line as an alternative to the onsite emergency diesel generator for
fire events involving the control room, the cable spreading room, and
fire zones RB-1, RB-2, RB-3, and RB-4 when offsite power is not
available.
III
By letter dated April 4, 1996, as supplemented by letters dated May
21, 1996, November 4, 1996, December 13, 1996, January 8, 1996 (sic
[1997]), January 15, 1997, February 19, 1997, May 16, 1997, and August
7, 1997, VYNPC, the licensee for Vermont Yankee, requested exemptions
from certain technical requirements of Section III.G and Section III.L
of Appendix R to 10 CFR Part 50.
The licensee requested exemptions (1) from the technical
requirements of Section III.G.1.a and Section III.L.2 of Appendix R to
allow the use of the ADS in conjunction with low-pressure injection
systems (either CS or low-pressure coolant injection [LPCI]) as a means
of achieving post-fire safe shutdown conditions in reactor building
fire zones RB-1, RB-2, RB-3, and RB-4; (2) from the technical
requirements of Section III.L.3 of Appendix R to allow the use of the
Vernon tie-line as an alternative to the onsite emergency diesel
generator for fire events involving the control room, the cable
spreading room, and fire zones RB-1, RB-2, RB-3, and RB-4 when offsite
power is not available; and (3) from the technical requirements of
Section III.G.3 of Appendix R to the extent that it requires that fire
detection and fixed fire suppression be provided in areas for which an
alternative safe-shutdown capability is provided for fire zones RB-1,
RB-2, RB-3, and RB-4.
On the basis of the NRC staff's evaluation, and contingent on the
installation of additional fire detection capability (as the licensee
committed to in its submittal of January 15, 1997, and May 16, 1997),
the staff concluded that the detection and suppression capabilities for
fire zones RB-1, RB-2, RB-3, and RB-4 are adequate to protect against
fire hazards in the zones. The staff concluded further that a
postulated fire in reactor building fire zones RB-1, RB-2, RB-3, and
RB-4 would not prevent the operators from achieving and maintaining
safe shutdown. Therefore, contingent on the installation of the
additional fire detection capability in fire zone RB-4, the licensee
should be granted an exemption from Section III.G.3 of Appendix R to 10
CFR Part 50 for reactor building fire zones RB-1, RB-2, RB-3, and RB-4.
On the bases of the technical evaluation contained in the appended
Brookhaven National Laboratory (BNL) technical evaluation report (TER),
and the NRC staff's evaluation of the Vermont Yankee fire protection
capabilities, the staff concluded that the licensee's revised shutdown
strategy for reactor building fire zones RB-1, RB-2, RB-3, and RB-4
(use of ADS with either LPCI or CS) and the redesignation of these fire
zones as areas requiring an alternative shutdown capability provide an
acceptable level of safe-shutdown protection. In addition, on the basis
of the technical evaluation contained in the BNL TER, the staff
concluded that the Vernon tie line provides an acceptable alternative
to power from an onsite emergency diesel generator when normal sources
of offsite power are not available for (1) a fire in the control room
or the cable spreading room that forces control room evacuation and (2)
a fire in reactor building fire zones RB-1, RB-2, RB-3, or RB-4 that
requires the use of the alternative post-fire safe-shutdown strategy.
Therefore, exemptions should be granted for Sections III.L.1.(c),
III.L.2.b, and III.L.3 of Appendix R to 10 CFR Part 50.
IV
Pursuant to 10 CFR 50.12(a)(2), the Commission will not consider
granting an exemption unless special circumstances are present. Item
(ii) of the subject regulation includes special circumstances in which
application of the subject regulation would not serve the underlying
purpose of the rule or is not necessary to achieve the underlying
purpose of the rule.
The underlying purpose of Section III.G of Appendix R is to provide
fire protection of equipment necessary for
[[Page 44154]]
safe-shutdown capability. On the basis of the NRC staff's evaluation
above and contingent on the installation of additional fire detection
capability (as the licensee committed to in its submittals of January
15, 1997, and May 16, 1997), the staff concluded that the detection and
suppression capabilities for fire zones RB-1, RB-2, RB-3, and RB-4 are
adequate to protect against the fire hazards in the zones. The staff
concluded further that a postulated fire in reactor building fire zones
RB-1, RB-2, RB-3, or RB-4 would not prevent the operators from
achieving and maintaining safe shutdown. Therefore, contingent on the
installation of the additional fire detection capability in fire zone
RB-4, the staff concludes that an exemption should be granted from
Section III.G.3 of Appendix R to 10 CFR Part 50 for reactor building
fire zones RB-1, RB-2, RB-3, and RB-4. Accordingly, the Commission has
determined that pursuant to 10 CFR 50.12(a)(2)(ii), special
circumstances exist for the licensee's requested exemption in that
imposition of the literal requirements of the regulation in these
particular circumstances is not necessary to achieve the underlying
purpose of Appendix R to 10 CFR Part 50.
The underlying purpose of Section III.L of Appendix R is to provide
alternative and dedicated shutdown capability necessary in areas in
which the fire protection features cannot ensure safe-shutdown
capability in the event of a fire in that area. On the bases of the
technical evaluation contained in the appended BNL TER and the NRC
staff evaluation of the Vermont Yankee fire protection capabilities,
the staff concluded that the licensee's revised shutdown strategy for
reactor building fire zones RB-1, RB-2, RB-3, and RB-4 (use of ADS with
either LPCI or CS) and the redesignation of these fire zones as areas
requiring an alternative shutdown capability provide an acceptable
level of safe-shutdown protection. In addition, on the basis of the
technical evaluation contained in the appended BNL TER, the staff
concluded that the Vernon tie-line provides an acceptable alternative
to power from an onsite emergency diesel generator when normal sources
of offsite power are not available for (1) a fire in the control room
or the cable spreading room that forces control room evacuation and (2)
for a fire in reactor building fire zones RB-1, RB-2, RB-3, and RB-4
that requires the use of the alternative post-fire safe-shutdown
strategy. Therefore, the staff concludes that exemptions should be
granted for Sections III.L.1.(c), III.L.2.b, and III.L.3 of Appendix R
to 10 CFR Part 50. Accordingly, the Commission has determined that,
pursuant to 10 CFR 50.12(a)(2)(ii), special circumstances exist in that
the proposed exemptions to III.L.1(c), III.L.2.b and III.L.3 satisfy
the underlying purpose of Appendix R to 10 CFR Part 50 and that
imposition of the literal requirements of the regulation in these
particular circumstances is not necessary to achieve the underlying
purpose of Appendix R to 10 CFR Part 50.
Further, the staff has concluded that the requested exemption is
authorized by law, will not present an undue risk to public health and
safety, and is consistent with the common defense and security.
Therefore, contingent upon the addition of additional fire detection
capability (as the licensee agreed to in its submittals of January 15,
1997 and May 16, 1997) by December 31, 1997, and contingent upon one
continuous fire watch monitoring both fire zones RB-3 and RB-4 until
installation of the additional fire detection capability, the
Commission hereby grants the request for exemption from the
requirements of Sections III.G.3, III.L.1(c), III.L.2.b, and III.L.3 of
Appendix R to 10 CFR Part 50 described in Section III above.
Pursuant to 10 CFR 51.32, the Commission has determined that the
issuance of this exemption will have no significant impact on the
quality of the human environment (62 FR 30356).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 12th day of August 1997.
For The Nuclear Regulatory Commission.
Samuel J. Collins,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 97-21896 Filed 8-18-97; 8:45 am]
BILLING CODE 7590-01-P