[Federal Register Volume 63, Number 75 (Monday, April 20, 1998)]
[Notices]
[Pages 19532-19534]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-10332]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-423]


Northeast Nuclear Energy Company; Notice of Consideration of 
Issuance of Amendment to Facility Operating License, Proposed no 
Significant Hazards Consideration Determination, and Opportunity for a 
Hearing

    The U.S. Nuclear Regulatory Commission (the Commission) is 
considering issuance of an amendment to Facility Operating License No. 
NPF-49 issued to Northeast Nuclear Energy Company (the licensee) for 
operation of Millstone Nuclear Power Station, Unit 3, located in New 
London County, Connecticut. The proposed change to Technical 
Specification (TS) 3/4.4.4, Relief Valves, would ensure that the Power-
Operated Relief Valves (PORVs) will be capable of automatic cycling as 
well as manual cycling when in the TS 3/4.4.4 action statements that 
allow indefinite continued operation. The proposed amendment also makes 
an editorial change, adds PORV surveillance requirements, and modifies 
the associated Bases section. The proposed changes provide added 
assurance that the pressurizer safety relief valves will not be damaged 
due to water relief during an inadvertent safety injection event.
    Before issuance of the proposed license amendment, the Commission 
will have made findings required by the Atomic Energy Act of 1954, as 
amended (the Act) and the Commission's regulations.
    The Commission has made a proposed determination that the amendment 
request involves no significant hazards consideration. Under the 
Commission's regulations in 10 CFR 50.92, this means that operation of 
the facility in accordance with the proposed amendment would not (1) 
involve a significant increase in the probability or consequences of an 
accident previously evaluated; or (2) create the possibility of a new 
or different kind of accident from any accident previously evaluated; 
or (3) involve a significant reduction in a margin of safety. As 
required by 10 CFR 50.91(a), the licensee has provided its analysis of 
the issue of no significant hazards consideration, which is presented 
below:

    NNECO has reviewed the proposed revision in accordance with 
10CFR50.92 and has concluded that the revision does not involve a 
significant hazards consideration (SHC). The basis for this 
conclusion is that the three criteria of 10CFR50.92(c) are not 
satisfied. The proposed revision does not involve [an] SHC because 
the revision would not:
    1. Involve a significant increase in the probability or 
consequence of an accident previously evaluated.
    Currently, timely operator action is required to prevent the 
pressurizer from filling and potentially challenging the pressurizer 
safety valves under water relief. The proposed TS changes provide 
added assurance that the safety valves will not be challenged by 
requiring the PORVs to be available for automatic pressure control. 
The changes to the Surveillance Requirements add the appropriate 
requirements to provide assurance that the automatic capability of 
the PORVs is OPERABLE. The quarterly analog channel operational test 
for the PORV high pressurizer pressure channels will not include 
valve operation. However, it does involve changing the opening logic 
from 2/4 to 1/3 and, thus, performing the surveillance increases the 
probability of the PORVs opening inadvertently. If the automatic 
capability of one PORV is INOPERABLE for more than 72 hours, 
shutdown is required. If the automatic capability of both PORVs is 
INOPERABLE for more than one hour, shutdown is required. If the 
block valves have been closed but the automatic capability of the 
PORVs is OPERABLE, an EOP [emergency operating procedure] change has 
been made to assure that the PORV block valve would be opened within 
ten minutes of an Inadvertent ECCS [emergency core cooling system] 
actuation at power. The new analysis shows that this is sufficient 
to assure that the PORVs would control RCS [reactor coolant system] 
pressure if water relief is experienced and the safety valves would 
not be challenged. Thus, it is concluded that the change provides 
added assurance that the safety valves would not fail due to water 
discharge.
    Evaluations and analysis have been performed to demonstrate that 
the PORVs and the associated piping are qualified for water relief 
from an Inadvertent ECCS Actuation at Power Operation for one hour 
from event initiation. This provides significant margin for operator 
action to terminate the event.
    The PORV control logic has been upgraded to be safety grade and 
single failure proof. A 2/4 logic is used for opening and 3/4 logic 
is used for subsequent closure. With the upgrade of the PORV control 
logic, there is added assurance that the PORV will be capable of 
providing automatic pressure control and preventing challenges to 
the safety valves, particularly under water solid conditions. 
However, there is a small impact on the probability of inadvertent 
opening of both PORVs resulting from multiple channel failures. With 
the new safety grade PORV control logic, two failed high pressurizer 
pressure channels will result in inadvertent opening of both PORVs. 
With the current logic, a single failed high pressurizer pressure 
channel would result in opening a PORV. However, the 2/4 closure 
logic will re-close the PORV when pressurizer pressure drops below 
2200 psia. With the current logic three failed high pressurizer 
pressure channels are required for the PORVs to inadvertently open 
and remain open. Thus it is concluded that there is an increase in 
the probability that the PORVs will inadvertently open and remain 
open.
    However, multiple channels failing high are required for the 
PORVs to inadvertently open and remain open. For failure modes such 
as loss of power for the transmitter or a failure of the instrument 
tubing, the channel will fail low. Failure modes that can result in 
the channel failing high are highly unlikely. Further, the new logic 
will require energization in order to open the PORVs, further 
minimizing the potential for inadvertent opening. These failures, 
which result in the PORVs automatically opening and remaining open, 
do not disable the ability of the operators to close the PORVs by 
taking their control switch to the close position. Thus, it is 
concluded that the increase in risk is negligible. The consequences 
of inadvertent opening of both PORVs is bounded by the analysis 
provided in Chapter 15.6.1 Inadvertent Opening of Pressurizer Safety 
or Relief Valve.
    In the event of an inoperable pressurizer pressure channel, the 
channel will be placed in the tripped condition. This will change 
the opening logic from 2/4 to 1/3 and the subsequent closure logic 
from 3/4 to 3/3.

[[Page 19533]]

This means that, when a pressurizer pressure channel is inoperable, 
a single failure of a pressurizer pressure channel high will cause 
both PORVs to open and remain open. Thus it is concluded that the 
Technical Requirements Manual (TRM) change which addresses specific 
surveillance controls, also results in an increase in the 
probability that the PORVs will inadvertently open and remain open. 
However, procedural controls will be implemented and controlled in 
the TRM that will require a plant shutdown if the channel is 
inoperable for more than thirty days.
    The setpoint for the PORV opening logic has been selected to 
assure that the PORVs will open prior to the safety valves, taking 
into account instrument uncertainties. The setpoint will be 
specified and controlled in the Technical Requirements Manual. This 
minimizes the potential challenges to the pressurizer safety valves 
under steam as well as water solid conditions. The PORV closure 
logic will be 3/4 that actuates when pressurizer pressure drops 20 
psi below the opening setpoint. Since the stroke time for the PORV 
is very short, the closing pressure is adequate to assure that the 
valve will cycle as designed.
    An EOP [Emergency Operating Procedure] change will direct the 
operator to open the PORV block valve if it has been closed due to 
excessive seat leakage. The EOP change will not result in the 
opening of the PORV block valve when the power has been removed when 
required to prevent a small break LOCA [loss-of-coolant accident]. 
This includes leakage from the PORV such that there is no assurance 
that the PORV would re-close as required to control RCS pressure. 
Thus, the PORV block valve would be opened only when there is 
assurance that the PORV will open and re-close as required. Thus, 
the EOP change does not impact the probability of a failed open 
PORV.
    Credit is now being taken for the PORVs to prevent challenges to 
pressurizer safety valves under water relief. If the PORVs were to 
fail to control RCS pressure, it is possible for water relief 
through the safety valves to occur. This also can result if both of 
the PORV block valves cannot be opened. Since the safety valves and 
the associated piping are not qualified for water relief, the valves 
may be damaged and may not reseat, resulting in an unisolable RCS 
leak. However, this would require multiple failures since the PORVs 
are redundant. The accident analysis has shown that DNB [departure 
from nucleate boiling] is not a concern and thus, there would be no 
failed fuel associated with this event. In addition, any RCS leakage 
would be inside containment. The analysis provided in FSAR [Final 
Safety Analysis Report] Section 15.6.1 for an Inadvertent Opening of 
a Pressurizer Safety or Relief Valve bounds the opening of both 
PORVs since the capacity of two PORVs is equivalent to one 
pressurizer safety valve.
    Thus it is concluded that the proposed changes do not involve a 
significant increase in the probability or consequence of an 
accident previously evaluated.
    2. Create the possibility of a new or different kind of accident 
from any accident previously evaluated.
    The changes provide added assurance that an Inadvertent ECCS 
Actuation at Power Operation will be mitigated and meet the 
requirement that a moderate frequency event will not lead to a more 
serious event without additional failures. The PORVs and associated 
piping have been qualified for water relief. In addition the PORVs 
are QA [Quality Assurance] equipment and are single failure proof. 
The TS changes provide assurance that the PORV automatic function 
will be OPERABLE or the plant will be shutdown. By crediting the 
PORVs, there is added assurance that the operators will terminate 
the event and prevent water relief from the safety valves for which 
they are not qualified. Since all criteria are met for this event, 
this does not represent the possibility of an accident of a 
different type.
    Because of the change in the PORV automatic actuation circuitry 
and the changes in the channel operability and surveillance 
requirements, the change does increase the probability of an 
Inadvertent Opening of both PORVs but the consequences are bounded 
by the analysis provided in FSAR Section 15.6.1 for Inadvertent 
Opening of a Safety or Relief Valve. Thus, this does not represent 
an accident of a different type.
    Credit is being taken for the operator to open a PORV block 
valve if it has been closed due to excessive PORV seat leakage. The 
PORV block valve will be opened following a Safety Injection 
actuation only after it has been determined that RCS pressure is 
above the HPSI [high pressure safety injection] shut off head. This 
means that charging is sufficient to maintain RCS pressure well 
above the RCS pressure predicted for the limiting LOCA analysis. 
Further, the PORV block valve would not be opened when power has 
been removed because of the potential for operation of the PORV to 
result in a small break LOCA. Further, the potential for opening the 
PORV block valve when the PORV is needed for accident mitigation is 
already addressed in the TS and is part of the licensing basis. 
Thus, this does not create the possibility of an accident of a 
different type.
    3. Involve a significant reduction in a margin of safety.
    With the proposed changes, all criteria for the Inadvertent ECCS 
actuation at Power Operation are met. The changes provide added 
assurance that a moderate frequency event would not result in a more 
serious event without additional failures. The TS changes and EOP 
change provide added assurance that the PORVs would be available to 
mitigate this event. Opening the block valve when the PORV can be 
used to mitigate an accident without the potential for a small break 
LOCA is already addressed in the TS and is part of the licensing 
basis. Inadvertent Opening of both PORVs is bounded by the Chapter 
15 accident analysis. Thus, it is concluded that the changes have no 
impact on the margin of safety.
    In conclusion, based on the information provided, it is 
determined that the proposed revision does not involve an SHC.

    The NRC staff has reviewed the licensee's analysis and, based on 
this review, it appears that the three standards of 10 CFR 50.92(c) are 
satisfied. Therefore, the NRC staff proposes to determine that the 
amendment request involves no significant hazards consideration.
    The Commission is seeking public comments on this proposed 
determination. Any comments received within 30 days after the date of 
publication of this notice will be considered in making any final 
determination.
    Normally, the Commission will not issue the amendment until the 
expiration of the 30-day notice period. However, should circumstances 
change during the notice period such that failure to act in a timely 
way would result, for example, in derating or shutdown of the facility, 
the Commission may issue the license amendment before the expiration of 
the 30-day notice period, provided that its final determination is that 
the amendment involves no significant hazards consideration. The final 
determination will consider all public and State comments received. 
Should the Commission take this action, it will publish in the Federal 
Register a notice of issuance and provide for opportunity for a hearing 
after issuance. The Commission expects that the need to take this 
action will occur very infrequently.
    Written comments may be submitted by mail to the Chief, Rules and 
Directives Branch, Division of Administrative Services, Office of 
Administration, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001, and should cite the publication date and page number of 
this Federal Register notice. Written comments may also be delivered to 
Room 6D59, Two White Flint North, 11545 Rockville Pike, Rockville, 
Maryland, from 7:30 a.m. to 4:15 p.m. Federal workdays. Copies of 
written comments received may be examined at the NRC Public Document 
Room, the Gelman Building, 2120 L Street, NW., Washington, DC.
    The filing of requests for hearing and petitions for leave to 
intervene is discussed below.
    By May 20, 1998, the licensee may file a request for a hearing with 
respect to issuance of the amendment to the subject facility operating 
license and any person whose interest may be affected by this 
proceeding and who wishes to participate as a party in the proceeding 
must file a written request for a hearing and a petition for leave to 
intervene. Requests for a hearing and a petition for leave to intervene 
shall be filed in accordance with the Commission's ``Rules of Practice 
for Domestic Licensing Proceedings'' in 10 CFR Part 2. Interested 
persons should

[[Page 19534]]

consult a current copy of 10 CFR 2.714 which is available at the 
Commission's Public Document Room, the Gelman Building, 2120 L Street, 
NW., Washington, DC, and at the local public document room located at 
the Learning Resources Center, Three Rivers Community-Technical 
College, 574 New London Turnpike, Norwich, Connecticut, and at the 
Waterford Library, ATTN: Vince Juliano, 49 Rope Ferry Road, Waterford, 
Connecticut. If a request for a hearing or petition for leave to 
intervene is filed by the above date, the Commission or an Atomic 
Safety and Licensing Board, designated by the Commission or by the 
Chairman of the Atomic Safety and Licensing Board Panel, will rule on 
the request and/or petition; and the Secretary or the designated Atomic 
Safety and Licensing Board will issue a notice of hearing or an 
appropriate order.
    As required by 10 CFR 2.714, a petition for leave to intervene 
shall set forth with particularity the interest of the petitioner in 
the proceeding, and how that interest may be affected by the results of 
the proceeding. The petition should specifically explain the reasons 
why intervention should be permitted with particular reference to the 
following factors: (1) the nature of the petitioner's right under the 
Act to be made party to the proceeding; (2) the nature and extent of 
the petitioner's property, financial, or other interest in the 
proceeding; and (3) the possible effect of any order which may be 
entered in the proceeding on the petitioner's interest. The petition 
should also identify the specific aspect(s) of the subject matter of 
the proceeding as to which petitioner wishes to intervene. Any person 
who has filed a petition for leave to intervene or who has been 
admitted as a party may amend the petition without requesting leave of 
the Board up to 15 days prior to the first prehearing conference 
scheduled in the proceeding, but such an amended petition must satisfy 
the specificity requirements described above.
    Not later than 15 days prior to the first prehearing conference 
scheduled in the proceeding, a petitioner shall file a supplement to 
the petition to intervene which must include a list of the contentions 
which are sought to be litigated in the matter. Each contention must 
consist of a specific statement of the issue of law or fact to be 
raised or controverted. In addition, the petitioner shall provide a 
brief explanation of the bases of the contention and a concise 
statement of the alleged facts or expert opinion which support the 
contention and on which the petitioner intends to rely in proving the 
contention at the hearing. The petitioner must also provide references 
to those specific sources and documents of which the petitioner is 
aware and on which the petitioner intends to rely to establish those 
facts or expert opinion. Petitioner must provide sufficient information 
to show that a genuine dispute exists with the applicant on a material 
issue of law or fact. Contentions shall be limited to matters within 
the scope of the amendment under consideration. The contention must be 
one which, if proven, would entitle the petitioner to relief. A 
petitioner who fails to file such a supplement which satisfies these 
requirements with respect to at least one contention will not be 
permitted to participate as a party.
    Those permitted to intervene become parties to the proceeding, 
subject to any limitations in the order granting leave to intervene, 
and have the opportunity to participate fully in the conduct of the 
hearing, including the opportunity to present evidence and cross-
examine witnesses.
    If a hearing is requested, the Commission will make a final 
determination on the issue of no significant hazards consideration. The 
final determination will serve to decide when the hearing is held.
    If the final determination is that the amendment request involves 
no significant hazards consideration, the Commission may issue the 
amendment and make it immediately effective, notwithstanding the 
request for a hearing. Any hearing held would take place after issuance 
of the amendment.
    If the final determination is that the amendment request involves a 
significant hazards consideration, any hearing held would take place 
before the issuance of any amendment.
    A request for a hearing or a petition for leave to intervene must 
be filed with the Secretary of the Commission, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, Attention: Rulemakings and 
Adjudications Staff, or may be delivered to the Commission's Public 
Document Room, the Gelman Building, 2120 L Street, NW., Washington, DC, 
by the above date. A copy of the petition should also be sent to the 
Office of the General Counsel, U.S. Nuclear Regulatory Commission, 
Washington, DC 20555-0001, and to Lillian M. Cuoco, Esq., Senior 
Nuclear Counsel, Northeast Utilities Service Company, P.O. Box 270, 
Hartford, Connecticut, 06141-0270, attorney for the licensee.
    Nontimely filings of petitions for leave to intervene, amended 
petitions, supplemental petitions and/or requests for hearing will not 
be entertained absent a determination by the Commission, the presiding 
officer or the presiding Atomic Safety and Licensing Board that the 
petition and/or request should be granted based upon a balancing of the 
factors specified in 10 CFR 2.714(a)(1)(I)-(v) and 2.714(d).
    For further details with respect to this action, see the 
application for amendment dated April 14, 1998, which is available for 
public inspection at the Commission's Public Document Room, the Gelman 
Building, 2120 L Street, NW., Washington, DC, and at the local public 
document room located at the Learning Resources Center, Three Rivers 
Community-Technical College, 574 New London Turnpike, Norwich, 
Connecticut, and at the Waterford Library, ATTN: Vince Juliano, 49 Rope 
Ferry Road, Waterford, Connecticut.

    Dated at Rockville, Maryland, this 15th day of April 1998.

    For the Nuclear Regulatory Commission.
Stephen Dembek,
Project Manager, Special Projects Office--Licensing, Office of Nuclear 
Reactor Regulation.
[FR Doc. 98-10332 Filed 4-17-98; 8:45 am]
BILLING CODE 7590-01-P