Federal Register / Vol. 60, No. 98 / Monday, May 22, 1995 / Notices 27141

that would result from the proposed

action, alternatives need not be

evaluated.

Alternative Use of Resources

This action does not involve the use

of any resources not previously

considered in the Final Environmental

Statement for FSV.

Agencies and Persons Consulted

The license initiated this exemption,

and the NRC staff is reviewing its

request. The State of Colorado was

notified of the proposed exemption.

State Officials had no comments on the

exemption.

Finding of No Significant Impact

NRC has determined not to prepare an

environmental impact statement for the

proposed exemption.

Based on this environmental

assessment, the staff concludes that the

proposed action will not have a

significant effect on the quality of the

human environment.

For further details on this action, see

the licensee’s application dated

February 16, 1995, which is available

for public inspection at the NRC’s

Public Document Room, 2120 L Street,

NW, Washington, DC 20037, and at the

local public document room at the Weld

Library District.—Downtown Branch,

919 7th Street, Greeley, CO 80631.

For the Nuclear Regulatory Commission.

Dated at Rockville, Maryland, this 12th day

of May, 1995.

Michael F. Weber,

Chief, Low-Level Waste and Decommissioning

Projects Branch, Division of Waste

Management, Office of Nuclear material

Safety and Safeguards.

[FR Doc. 95–12471 Filed 5–19–95; 8:45 am]

BILLING CODE 7590–01–M

Proposed Generic Communication

Testing of Safety-Related Logic

Circuits

AGENCY: Nuclear Regulatory

Commission.

ACTION: Notice of opportunity for public

comment.

SUMMARY: The Nuclear Regulatory

Commission (NRC) is proposing to issue

a generic letter concerning problems

with the testing of safety-related logic

circuits. This draft generic letter

requests addresses to review

surveillance procedures to determine

whether any of the procedures fail to

test all required portions of the logic

circuitry and, if any problems are found,

to correct the problems. The NRC is

seeking comment from interested parties

regarding both the technical and

regulatory aspects of the proposed

generic letter presented under the

Supplementary Information heading.

This proposed generic letter and

supporting documentation were

discussed in meeting number 272 of the

Committee to Review Generic

Requirements (CRGR) on April 25, 1995.

The relevant information that was sent

to the CRGR to support their review of

the proposed generic letter will be made

available in the NRC Public Document

Room. The NRC will consider

comments received from interested

parties in the final evaluation of the

proposed generic letter. The NRC’s final

evaluation will include a review of the

technical position and, when

appropriate, an analysis of the value/

impact on licensees. Should this generic

letter be issued by the NRC, it will

become available for public inspection

in the Public Document Rooms.

The staff recognizes that during

implementation of the requested actions

in the proposed generic letter, licensees

may identify conditions in violation of

their technical specifications or other

NRC requirements. Consequently, the

staff is considering the possibility of

exercising enforcement discretion under

certain circumstances during the period

of implementation of the requested

actions in order to encourage licensees

to perform effective reviews.

DATES: Comment period expires on July

21, 1995. Comments submitted after this

date will be considered if it is practical

to do so, but assurance of consideration

cannot be given except for comments

received on or before this date.

ADDRESSES: Submit written comments

to Chief, Rules Review and Directives

Branch, U.S. Nuclear Regulatory

Commission, Washington, DC 20555.

Written comments may also be

delivered to 11545 Rockville Pike,

Rockville, Maryland, from 7:30 am to

4:15 pm, Federal workdays. Copies of

written comments received may be

examined at the NRC Public Document

Room, 2120 L Street, NW., (Lower

Level), Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Hukam Garg, (301) 415–2929.

SUPPLEMENTARY INFORMATION:

NRC Generic Letter No. 95–XX: Testing

of Safety-Related Logic Circuits

Addresses

All holders of operating licenses or

construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory

Commission (NRC) is issuing this

generic letter to: (1) notify addressees

about problems with testing of safetyrelated logic circuits, (2) request that all

addresses implement the actions

described herein, and (3) require that all

addressees submit a written response to

this generic letter regarding

implementation of the requested

actions.

Background

The Nuclear Regulatory Commission

staff had previously issued the

following information notices (INs)

regarding problems with testing of

safety-related logic circuits: IN 88–83,

‘‘Inadequate Testing of Relay Contacts

in Safety-Related Logic Circuits,’’ dated

October 19, 1988; IN 91–13, ‘‘Inadequate

Testing of Emergency Diesel Generators

(EDGs),’’ dated March 4, 1991; IN 92–40,

‘‘Inadequate Testing of Emergency Bus

Undervoltage Logic Circuitry,’’ dated

May 27, 1992; IN 93–15, ‘‘Failure to

Verify the Continuity of Shunt Trip

Attachment Contacts in Manual Safety

Injection and Reactor Trip Switches,’’

dated February 18, 1993; and IN 93–38,

‘‘Inadequate Testing of Engineered

Safety Features Actuation Systems,’’

dated May 24, 1993. Despite these

notices, recent events have occurred

similar to those described in the INs

which indicate that licensees have not

taken sufficient action to correct

previously identified problems in logic

circuit surveillance testing. On March 7,

1995, NRC issued IN 95–15,

‘‘Inadequate Logic Testing of SafetyRelated Circuits,’’ which informed

licensees about these recent events at

Cooper Nuclear Station, Fermi 2,

Waterford 3, Grand Gulf Nuclear

Station, and Arkansas Nuclear One,

Unit 1 and Unit 2.

Description of Circumstances

The NRC has documented a

significant number of instances

involving problems with logic testing of

safety-related circuits in the information

notices described above. These

information notices discuss events at

various pressurized water and boiling

water reactors. The examples of

problems with logic testing cover a wide

range of systems including safety

injection system actuation, containment

spray system actuation, residual heat

removal system actuation, diesel

generator load sequencing, and rector

protection system actuation. In most

cases, the affected logic circuits

functioned properly when testing in

accordance with technical specification
27142 Federal Register / Vol. 60, No. 98 / Monday, May 22, 1995 / Notices

(TS) requirements was performed. The

NRC has taken enforcement action in

many of these cases since they resulted

in violations. The details of these

instances are included in the

information notices cited above. An

example of the details associated with

this issue at Fermi Station are repeated

here.

On July 15, 1994, during a routine

review of surveillance procedures

required by the Fermi Unit 2 TS, the

licensee (Detroit Edison Company)

discovered that neither the procedures

used for testing the load shedding of the

4160 volt Residual heat Removal (RHR)

pumps nor the related instrumentation

and control (I&C) logic functional test

procedure provided for the full testing

of the RHR pump start logic. Also, the

test procedures did not include

verification that the switchgear breaker

would not close with an undervoltage

signal present at the bus.

After investigating further, the

licensee discovered additional

deficiencies in the undervoltage

functional test surveillance procedures

including the logic functional test

surveillance procedures for the three

other engineered safety buses. Also, the

surveillance test overlap did not include

sufficient overlap of the logic circuit to

cover the degraded voltage trip input to

the non-interruptible air supply system

isolation logic, the degraded voltage trip

input to the bus feeder breaker position,

and the alternative automatic closure

circuits for the EDG output breakers.

The licensee further determined that the

480 volt load shed logic had not been

fully tested.

On September 9, 1994, the licensee

identified additional surveillance

deficiencies and expanded the

investigation of its surveillance

procedures for EDGs and I&C overlap

testing. During this investigation, the

licensee determined that (1) multiple

pathways for starting an EDG through

the emergency core cooling system

(ECCS) logic were not being tested, (2)

emergency equipment cooling water

(EECW) actuation from the load

sequencer was not being differentiated

from EECW actuation on reactor

building closed cooling water low

pressure, and (3) test acceptance criteria

permitted performance outside of the TS

limits.

On November 30, 1994, the licensee

identified several other test deficiencies

in its surveillance procedures. These

deficiencies were related to the core

spray system, RHR system, reactor

protection system, safety relief valves,

alternate rod insertion and main steam

isolation valve leadage control system

logic, remote shutdown panel, primary

containment manual isolation valves,

and alternate shutdown panel transfer

switches.

To address the above deficiencies, the

licensee has taken the following

correction actions: (1) Reviewed

deficient procedures and performed

required surveillance to establish

operability, (2) reviewed similar

procedures to identify other

deficiencies. The licensee has taken the

following corrective actions: (1)

reviewed deficient procedures and

performed required surveillance to

establish operability, (2) reviewed

similar procedures to identify other

deficiencies, (3) created electrical

overlap drawings, and (4) trained

authors and technical reviewers of

procedures to be fully aware of logic

surveillance requirements. The NRC

staff issued a notice of violation to

Detroit Edison Company concerning the

above issue (NRC Inspection Report No.

50–341/94–12).

Discussion

A number of NRC regulations

document the requirements to test

safety-related systems to ensure that

they will function as designed when

called upon. For example, Title 10 of

the Code of Federal Regulations (10

CFR), Section 50.36, ‘‘Technical

Specifications,’’ paragraph (c)(3) states

that, ‘‘surveillance requirements are

requirements relating to test, calibration

or inspection to assure that the

necessary quality of systems and

components is maintained, that facility

operation will be within the safety

limits, and that the limiting conditions

of operation will be met.’’ surveillance

requirements to assure continued

operability of safety related logic

circuits have been included in the plantspecific technical specifications for all

operating nuclear power plants

Other documents that provide a basis

for these requirements include:

• 10 CFR 50.55a, ‘‘Codes and

Standards,’’ paragraph (h) which

includes reference to Institute of

Electrical and Electronic Engineers

(IEEE) Standard 279, ‘‘Criteria for

Protection Systems for Nuclear Power

Generating Stations’’

• Appendix A to 10 CFR 50, General

Design Criterion (GDC) 21, ‘Protection

System for Reliability and Testability’’

• Appendix A to 10 CFR 50, General

Design Criterion (GDC) 18, ‘‘Inspection

and Testing of Electric Power Systems’’

• Appendix B to 10 CFR 50, Criterion

XI, ‘‘Test Control’’

• Regulatory Guide (RG) 1.118,

‘‘Periodic Testing of Electric Power and

Protection Systems’’

• RG 1.32, ‘‘Criteria for Safety-Related

Electric Power Systems for Nuclear

Power Plants’’

As noted above, the NRC staff has

issued a number of information notices

(identified in the ‘‘Background’’ section)

that document identified deficiencies in

actuation logic surveillance test

programs. However, because of the

number of more recently identified

similar deficiencies, the NRC staff has

determined that licensees may not have

yet adequately addressed this issue and

further action is necessary.

The NRC staff finds that the failure to

adequately test safety-related actuation

logic circuitry is safety significant in

that inoperable essential electric

components required for automatic

actuation of post-accident mitigation

systems may be undetected for extended

periods. This is particularly true for the

reactor protection system, whose

unavailability is shown in probabilistic

risk assessments to be a dominant

contributor to potential core damage

scenarios. Undetected reactor protection

system availability/reliability

degradation is also a potentially

significant contributor to overall risk.

Unavailability of those circuits

associated with automatic emergency

core cooling system (ECCS) actuation,

especially in a loss-of-offsite-power

situation, is a lesser contributor to

overall risk but is important in ensuring

post-accident recovery in accordance

with licensing bases. Failure to

automatically actuate safety systems

also places the additional burden on the

operators of having to manually actuate

required functions and thus increases

the chance for operator error.

The NRC staff notes that even in cases

where surveillance testing of the logic

circuits has not been complete, it is

likely that only very small portions of

the circuit have been omitted from the

test. Further, the NRC staff is not aware

of instances of specifically identified

surveillance inadequacies that resulted

in the unavailability of the safety system

when called on during an event.

Nevertheless, as indicated above, the

NRC staff finds that compliance with

the plant-specific technical

specifications is essential in order to

maintain the validity of the assumptions

in the licensing basis accident analyses.

On the basis of the recent events,

previously issued INs, complexity of the

logic, and contribution to the core

damage frequency, the NRC staff has

further determined that licensees should

review their surveillance procedures for

the reactor protection system, EDG load

shedding and sequencing, and actuation

logic for the engineered safety features

systems to ensure that complete testing
Federal Register / Vol. 60, No. 98 / Monday, May 22, 1995 / Notices 27143

is being performed as required by the

technical specifications.

Requested Actions

The NRC staff requests that all holders

of operating licenses for nuclear power

reactors take the following actions:

(1) Compare electrical schematic

drawings and logic diagrams for the

reactor protection system, EDG load

shedding and sequencing and actuation

logic for the engineered safety features

systems against technical specification

surveillance test procedures to ensure

that all portions of the logic circuitry,

including the parallel logic, interlocks,

bypasses and inhibit circuits, are

adequately covered in the surveillance

procedures. This review should also

include relay contacts, control switches,

and other relevant electrical

components within these systems,

utilized in the logic circuits.

(2) Modify the surveillance

procedures as necessary for complete

testing to comply with the technical

specifications. Additionally, the

licensee may request an amendment to

the technical specifications if relief from

certain testing requirements can be

justified.

It is requested the completion of these

actions not go beyond the first refueling

outage commencing 90 days after the

issuance of this generic letter.

Note: Some licensees may have already

performed the requested reviews and taken

appropriate corrective actions. These

licensees do not need to perform any

additional review unless modifications have

been made to the logic circuits for these

systems. In these cases the modifications

should be reviewed.

Required Response

All addressees, including those who

have already completed the requested

actions, are required to submit a written

response to this generic letter as follows:

(1) Within 60 days of the date of this

generic letter, a written response

indicating whether or not the addressee

will implement the actions requested

above. If the addressee intends to

implement the requested actions,

submit a schedule for completing

implementation. If an addressee chooses

not to take the requested actions, submit

a description of any proposed

alternative course of action, the

schedule for completing the alternative

course of action (if applicable), and the

safety basis for determining the

acceptability of the planned alternative

course of action.

(2) Within 30 days of completion of

the requested actions, a response

confirming completion.

Backfit Discussion

The actions requested in this generic

letter are considered backfits in

accordance with NRC procedures.

Because established regulatory

requirements exist but were not

satisfied, these backfits are necessary to

bring the addressees into compliance

with existing requirements. Therefore,

on the basis of 10 CFR 50.109(a)(4)(i), a

full backfit analysis was not performed.

An evaluation was performed in

accordance with NRC procedures,

including a statement of the objectives

of and reasons for the requested actions

and the basis for invoking the

compliance exception. Response to

question ix in the CRGR review package

contains this evaluation.

Dated at Rockville, Maryland, this 15th day

of May, 1995.

For the Nuclear Regulatory Commission.

Brian K. Grimes,

Director, Division of Project Support, Office

of Nuclear Reactor Regulation.

[FR Doc. 95–12468 Filed 5–19–95; 8:45 am]

BILLING CODE 7590–01–M

Advisory Committee on Reactor

Safeguards; Meeting Agenda

In accordance with the purposes of

Sections 29 and 182b. of the Atomic

Energy Act (42 U.S.C. 2039, 2232b), the

Advisory Committee on Reactor

Safeguards will hold a meeting on June

8–10, 1995, in Conference Room T2B3,

11545 Rockville Pike, Rockville,

Maryland. The date of this meeting was

previously published in the Federal

Register on Wednesday, December 28,

1994 (59 FR 66977).

Thursday, June 8, 1995

8:30 a.m.–8:45 a.m.: Opening

Remarks by the ACRS Chairman

(Open)—The ACRS Chairman will make

opening remarks regarding conduct of

the meeting and comment briefly

regarding items of current interest.

During this session, the Committee will

discuss priorities for preparation of

ACRS reports.

8:45 a.m.–9:15 a.m.: Preparation for

Meeting with the Commissioners

(Open)—The Committee will discuss

topics scheduled for the meeting with

the Commissioners.

9:30 a.m.–11:00 a.m.: Meeting with

the Commissioners (Open)—The

Committee will meet with the

Commissioners, in the Commissioner’s

Conference Room, One White Flint

North, to discuss items of mutual

interest.

11:15 a.m.–12:00 noon: Ethics

Training (Open)—The Committee will

hear presentations by and hold

discussions with representatives of the

NRC Office of the General Counsel

regarding the provisions of the Ethics

regulations which apply to Special

Government Employees.

1:00 p.m.–3:00 p.m.: Proposed Final

PRA Policy Statement (Open)—The

Committee will hear presentations by

and hold discussions with

representatives of the NRC staff

regarding the proposed Final PRA

Policy Statement. Also representatives

of the Nuclear Energy Institute (NEI)

will brief the Committee regarding the

NEI/EPRI Probabilistic Safety

Assessment (PSA) Application Guide.

3:15 p.m.–4:45 p.m.: Proposed Final

Rule on Reactor Vessel Annealing

(Open)—The Committee will hear

presentations by and hold discussions

with representatives of the NRC staff

regarding the proposed final rule on

reactor vessel annealing.

Representatives of the industry will

participate, as appropriate.

5:00 p.m.–6:30 p.m.: Preparation of

ACRS Reports (Open)—The Committee

will discuss proposed ACRS reports on

matters considered during this meeting.

Friday, June 9, 1995

8:30 a.m.–8:35 a.m.: Opening

Remarks by the ACRS Chairman

(Open)—The ACRS Chairman will make

opening remarks regarding conduct of

the meeting.

8:35 a.m.–9:45 a.m.: Status of Issues

Associated with the AP600 Design

Certification Review (Open)—The

Committee will hear presentations by

and hold discussions with

representatives of the NRC staff

regarding the status of issues associated

with the AP600 design certification

review.

Representatives of the industry will

participate, as appropriate.

9:45 a.m.–10:45 a.m.: Policy and

Technical Issues for Passive Plant

Designs (Open)—The Committee will

hear presentations by and hold

discussions with representatives of the

NRC staff regarding policy and technical

issues for passive plant designs.

Representatives of the industry will

participate, as appropriate.

11:00 a.m.–12:30 p.m.: Prioritization

of Generic Safety Issues (GSIs) (Open)—

The Committee will hold discussions

with representatives of the NRC staff

regarding the comments from cognizant

subcommittee chairman on the priority

rankings proposed by the Staff for a

group of GSIs, and also the schedule for

prioritizing the remaining GSIs.

1:30 p.m.–2:30 p.m.: Fire-Protection

Related Issues (Open/Closed)—The

Committee will hear presentations by