[Federal Register Volume 63, Number 192 (Monday, October 5, 1998)]
[Notices]
[Pages 53466-53467]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-26558]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-313 and 50-368; License Nos. DPR-51 and NPF-6]
Entergy Operations, Inc. (Arkansas Nuclear One, Units 1 and 2);
Confirmatory Order Modifying Post-TMI Requirements Pertaining To
Containment Hydrogen Monitors
I
Entergy Operations, Inc. (the Licensee), is the holder of Facility
Operating License Nos. DPR-51 and NPF-6 issued by the Nuclear
Regulatory Commission (NRC or Commission) pursuant to 10 CFR Part 50.
The licenses authorize the operation of Arkansas Nuclear One, Units 1
and 2 (ANO-1, ANO-2), located in Pope County, Arkansas.
II
As a result of the accident at Three Mile Island, Unit 2 (TMI-2),
the NRC issued NUREG-0737, ``Clarification of TMI Action Plan
Requirements'' (November 1980). Generic Letters 82-05 and 82-10, issued
on March 17, and May 5, 1982, respectively, requested licensees of
operating power reactors to furnish information pertaining to their
implementation of specific TMI Action Plan items described in NUREG-
0737. Orders were issued to licensees confirming their commitments made
in response to the generic letters. Orders to the Licensee issued on
March 14, 1983, require the Licensee to implement and maintain the
various TMI Action Plan items, including Item II.F.1, Attachment 6
pertaining to monitoring of hydrogen concentration in containment.
Significant improvements have been achieved since the TMI accident
in the areas of understanding risks associated with nuclear plant
operations and developing better strategies for managing the response
to potentially severe accidents at nuclear plants. Recent insights
pertaining to plant risks and alternate severe accident assessment
tools have led the NRC staff to conclude that some TMI Action Plan
items can be revised without reducing, and perhaps enhancing, the
ability of licensees to respond to severe accidents. The NRC's efforts
to oversee the risks associated with nuclear technology more
effectively and to eliminate undue regulatory costs to licensees and
the public have prompted the NRC's decision to revise the post-TMI
requirement related to establishing indication of hydrogen
concentration in containment.
The confirmatory Orders of March 14, 1983 imposed requirements upon
the Licensee for having continuous indication of hydrogen concentration
in the containment atmosphere provided in the control room, as
described by TMI Action Plan Item II.F.1, Attachment 6. Information
about hydrogen concentration supports the Licensee's assessments of the
degree of core damage and whether a threat to the integrity of the
containment may be posed by combustion of the hydrogen gas. TMI Action
Item II.F.1, Attachment 6 states:
If an indication is not available at all times, continuous
indication and recording shall be functioning within 30 minutes of
the initiation of safety injection.
This requirement to have indication of the hydrogen concentration
in containment within 30 minutes following the start of an accident has
defined both design and operating characteristics for hydrogen
monitoring systems at nuclear power plants since the implementation of
NUREG-0737. In addition, the technical specifications of most nuclear
power plants and NRC regulations at 10 CFR 50.44, ``Standards for
combustible gas control system in light-water-cooled power reactors,''
require availability of hydrogen monitors.
By letter dated March 2, 1998, Entergy Operations, Inc., requested
relief for the two units at ANO from the requirement to have indication
of hydrogen concentration in containment within 30 minutes of the
initiation of safety injection. Specifically, the Licensee requested a
90-minute limit for indication of hydrogen concentration in
containment. The technical basis for this request was that the actions
necessary to establish the hydrogen indication are a distraction for
control room operators from more important tasks during the initial
attempts to respond to an event and that information provided by the
monitors is not used until later stages of responding to an accident.
The Licensee's request of March 2, 1998, was made in conjunction
with Task Zero of the Risk-Informed, Performance-Based Regulation Pilot
Program, an initiative undertaken by the NRC and the Nuclear Energy
Institute to improve the incorporation of risk-informed and
performance-based insights into the regulation of nuclear power plants.
Because the licenses for ANO-1 and ANO-2 were modified by the Orders of
March 14, 1983, imposing TMI Action Plan Item II.F.1, Attachment 6, the
staff informed the Licensee by letter dated July 22, 1998, that it was
necessary to submit an application for an amendment to the operating
licenses of ANO-1 and ANO-2 in accordance with 10 CFR 50.90 in order to
modify the time limit for post-accident hydrogen monitoring. Upon
further reflection, however, the NRC staff has decided that it could
act upon this request more expeditiously by issuance of this Order.
On the basis of the NRC staff's review of information provided by
the Licensee, consideration of the lessons learned since the TMI-2
accident pertaining to severe accident management and emergency
planning, and in order to make NRC licensing and regulatory oversight
more efficient, the staff concludes that the Licensee should have the
flexibility and assume the responsibility for determining the
appropriate time limit for indication of hydrogen concentration in
containment, such that control room personnel are not distracted from
more important tasks in the early phases of accident mitigation, and
decisionmakers, mostly outside the control room, are able to benefit
from having useful information on hydrogen concentration. Because the
appropriate balance between control room activities and longer term
[[Page 53467]]
management of the response to severe accidents can best be determined
by the Licensee, the NRC staff has determined that the Licensee may
elect to adopt a risk-informed functional requirement in lieu of the
current 30 minute time limit for indication of hydrogen concentration
as imposed by the Orders dated March 14, 1983, and as described by TMI
Action Item II.F.1, Attachment 6 in NUREG-0737. The applicable
functional requirement is as follows:
Procedures shall be established for ensuring that indication of
hydrogen concentration in the containment atmosphere is available in
a sufficiently timely manner to support the role of the information
in the Arkansas Nuclear One Emergency Plan (and related procedures)
and related activities such as guidance for severe accident
management. Hydrogen monitoring will be initiated on the basis of
(1) the appropriate priority for establishing indication of hydrogen
concentration within containment in relation to other activities in
the control room, (2) the use of the indication of hydrogen
concentration by decisionmakers for severe accident management and
emergency response, and (3) insights from experience or evaluation
pertaining to possible scenarios that result in significant
generation of hydrogen that would be indicative of core damage or a
potential threat to the integrity of the containment building.
Affected licensing-basis documents and other related documents will
be appropriately revised and/or updated in accordance with
applicable NRC regulations.
The Licensee's technical specifications and 10 CFR 50.44 require
the Licensee to maintain the ability to monitor hydrogen concentration
in containment. However, the details pertaining to the design and
manner of operation of the hydrogen monitoring system are determined by
the Licensee.
III
Following various discussions with the staff, the Licensee
submitted a letter dated September 9, 1998, in which it provided a
commitment to operate and maintain the containment hydrogen monitors
for ANO-1 and ANO-2 in accordance with the applicable functional
requirement described in Section II above. The Licensee stated that the
adoption of the functional requirement statement would initially result
in extending the time requirement for hydrogen monitors from 30 minutes
to 90 minutes after the initiation of safety injection.
I find that the Licensee's commitment as set forth in its letter of
September 9, 1998, is acceptable and conclude that with this commitment
the plant's safety is reasonably assured. In view of the foregoing, I
have determined that public health and safety require that the
Licensee's commitment be confirmed by this Order. During its
discussions with the NRC staff, the Licensee agreed to waive its right
to a hearing with respect to issuance of this Order.
IV
Accordingly, pursuant to Sections 103, 104b, 161b, 161i, 161o, and
182 of the Atomic Energy Act of 1954, as amended, and the Commission's
regulations in 10 CFR 2.202 and 10 CFR Part 50, it is hereby ordered
that:
(1) NRC License Nos. DPR-51 and NPF-6 are modified as follows:
The Licensee may elect to either maintain the 30-minute time limit
for indication of hydrogen in containment, as described by TMI Action
Plan Item II.F.1, Attachment 6, in NUREG-0737 and required by the
Confirmatory Orders of March 14, 1983, or modify the time limit in the
manner specified in Sections II and III of this Order.
(2) The licensee's commitments in its letter of September 9, 1998,
see Section III, above, are confirmed.
The Director, Office of Nuclear Reactor Regulation, may, in
writing, relax or rescind any of the above conditions upon
demonstration by the Licensee of good cause.
V
Any person adversely affected by this Confirmatory Order, other
than the Licensee, may request a hearing within 20 days of its
issuance. Where good cause is shown, consideration will be given to
extending the time to request a hearing. A request for extension of
time must be made in writing to the Director, Office of Nuclear Reactor
Regulation, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555-
0001, and include a statement of good cause for the extension. Any
request for a hearing shall be submitted to the Secretary, U.S. Nuclear
Regulatory Commission, ATTN: Chief, Rulemakings and Adjudications
Staff, Washington, D.C. 20555-0001. Copies of the hearing request shall
also be sent to the Director, Office of Nuclear Reactor Regulation,
U.S. Nuclear Regulatory Commission, Washington, D.C. 20555-0001; to the
Deputy Assistant General Counsel for Hearings and Enforcement at the
same address; to the Regional Administrator, NRC Region IV, 611 Ryan
Plaza Drive, Suite 400, Arlington, Texas 76011; and to Nicholas S.
Reynolds, Esquire, Winston and Strawn, 1400 L Street, N.W., Washington,
DC 20005-3502, attorney for the Licensee. If such a person requests a
hearing, that person will set forth with particularity the manner in
which his interest is adversely affected by this Order and will address
the criteria set forth in 10 CFR 2.714(d).
If the hearing is requested by a person whose interest is adversely
affected, the Commission will issue an Order designating the time and
place of any hearing. If a hearing is held, the issue to be considered
at such hearing will be whether this Confirmatory Order should be
sustained.
In the absence of any request for hearing, or written approval of
an extension of time in which to request a hearing, the provisions
specified in Section IV above will be final 20 days from the date of
this Order without further order or proceedings. If an extension of
time for requesting a hearing has been approved, the provisions
specified in Section IV will be final when the extension expires if a
hearing request has not been received.
Dated at Rockville, Maryland, this 28th day of September 1998.
For the Nuclear Regulatory Commission
Samuel J. Collins,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 98-26558 Filed 10-2-98; 8:45 am]
BILLING CODE 7590-01-P
