ML20024A875

Forwards Summary of Evaluation on Environ Qualification Confirming Previous conclusions.Nonsafety-related Electric Equipment Evaluated to Ensure That Failure Under Postulated Accident Conditions Could Not Prevent Intended Function

ML20024A875
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	06/24/1983
From:	James Smith LONG ISLAND LIGHTING CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
SNRC-911, NUDOCS 8307010112
Download: ML20024A875 (8)

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LONG ISLAND LIGHTING COMPANY i SHOREHAM NUCLEAR POWER STATION

- - _ _ -~ < P.O. BOX 618, NORTH COUNTRY ROAD e WADING RIVER, N.Y.11792 Direct Dial Number June 24, 1983 SNRC-911 Mr. Ilarold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Environmental Qualification Shoreham Nuclear Power Station - Unit 1 Docket No. 50-322

Dear Mr. Denton:

On January 21, 1983, the final rule on environmental qualification of electric equipment important to safety for nuclear power plants, 10CFR 5 50.49, was published in the Federal Register (48F.R.2729). Shortly thereafter, on January 26, 27 and 31, 1983, issues relating to environmental qualification at Shoreham were litigated before the Atomic Safety and Licensing Board. At that time, LILCO witnesses stated that, in their view, the entire scope of equipment covered by 10CFR d 50.49 had either been included in the Shoreham environmental qualification program or been suitably isolated from the performance of safety functions so as not to require environmental qualification. LILCO witnesses also stated that they intended to perform a further review of their conclusion as of that time. This letter reports on the results of that further review which confirms the conclusions expressed in January.

The final Environmental Qualification rule established a new  !

licensing requirement of identifying and qualifying a category of equipment important to safety which includes "nonsafety-related electric equipment whose failure under postulated environmental conditions could prevent satisfactory accomplishment of safety tunctions specified in subparagraphs (i) through (iii) of paragraph (b) (1) of this section by the safety-related equipment." LILCO evaluated this specific requirement of the rule, as discussed in Enclosure 1 and verified that there is no equipment at Shoreham that satisfies this condition. Therefore, there is no equipment installed at Shoreham that falls into this category (i.e., 10CFR50.49 (b) (2)). In addition, electric equipment important to safety covered by this rule includes "certain post accident monitoring equipment" in accordance with 8307010112 830624 PDR ADOCK 0500032 FC 8935.1 8 L t\

SNRC-911 June 24, 1983 Page 2 l

the specific guidance provided in Regulatory Guide 1.97, Rev. 2.

LILCO included this electric equipment in our Equipment Qualifica-tion Program as described in our submittal dated April 14, 1983, SNRC-863, Attachment C. We wish to point out that (a) these nonsafety-related electric equipment were inclut*.ed in the program to ensure compliance with the commission's regulations and (b) these same nonsafety-related equipment were evaluated to ensure that their failure under postulated accident conditions could not prevent safety-related electrical equipment from performing their intended function.

Should you have any questions regarding this matter, do not hesitate to contact this office.

Very truly yours,

. L. Smith Manager, Special Projects Shoreham Nuclear Power Station GJG/ law Enclosures cc: J. liiggins J. F. Etzweiler All Parties Listed in Attachment 1

ATTACHMENT 1 .

Lawrence Brenner, Esq. Herbert H.', Brown, Esq.

• Administrative Judge Lawrence Coe Lanpher, Esq.

Atomic Safety and Licensing Karla J. Lotsche, Esq.

Board Panel Kirkpatrick, Lockhart, Hill U.S. Nuclear Regulatory Cormission Christoper & Phillips Washington,.D.C. 20555 8th Floor 1900 M Street, N.W.

Washington, D.C. 20036 Dr.. Peter A. Morris

• Administrative Judge .

Atomic Safety and Licensing Mr. Marc W. Goldsmith Board Panel Energy Research Group U.S. Nuclear Regulatory Commission 4001 Totten Pond Rcad Washington, D.C. 20555 . Waltham, Massachusetts 02154 Dr. James H. Carpenter MHB Technical Associates Administrative Judge 1723 Hamilton Avenue Atomic Safety and Licensing Suite K Board Panel . San Jose, California 95125 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 "

Stephen B. Latham, Esq. -

Twomey, Latham & Shea Daniel F. Brown, Esq. 33 West Second Street Attorney P.O. Box 398 Atomic Safety and Licensing Riverhead, New York 11901 Board Panel -

U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Ralph Shapiro, Esq.

Cammer and Shapiro, P.C.

9 East 40th Street Bernard M. Bordenick, Esq. New York, New York 10016 David A. Repka, Esq. '

. U.S. Nuclear Regulatory Commission Washington, D.C. 20555 '

. ' Matthew J. Kelly, Esq.

State of New York

. Department of Public Service James Dougherty Three Empire State Plaza 3045 Porter Street  !

Albany, New York 12223 Washington, D.C. 20008 i l

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Enclosure 1 Summary of LILCO's Evaluation On Environmental Qualification 10CFR50.49 Shoreham Nuclear Power Station Long Island Lighting Company The LILCO program for environmental qualification of electrical equipment important to safety has been reviewed against the re-quirements of 10CFR50.49 (Enclosure 2). It has been concluded that the existing program for Shoreham equipment qualification complies with the intent and scope of 10CFR50.49.

The final rule establishes a new licensing requirement of identi-fying and qualifying a category of equipment important to safety which includes "nonsafety-related electric equipment whose failure under postulated environmental conditions could prevent satisfactory accomplishment of safety functions..." (paragraph (b)

(2), 10CFR50.49). LILCO's conclusion is that the Shoreham plant design is such that there is no equipment in this category.

Equipment for Shoreham has been classified as either " safety-related" or "nonsafety-related". Safety-related structures, systems and components must be designed to ensure accomplishment of the three basic safety functions:

1. the integrity of the reactor coolant pressure boundary,

2. the capability to shut down the reactor and maintain it in a safe shutdown condition, or

3. the capability to prevent or mitigate the consequences of accidents which could result in potential offsite exposures comparable to the guideline exposures of (10CFR Part 100).

Thus, in accordance with 10CFR50.49, a structure, system, or com-ponent at Shoreham is " safety-related" if required to assure one of these three safety-related functions. Conversely, any struc-ture, system,-or component that is not required to assure any of these safety-related functions is classified as "nonsafety-related".

Throughout the design and classification process, equipment which had the potential for affecting any of these safety functions was either classified as safety-related or isolated in such a manner. ,

as to assure no unacceptable interaction with respect to the safety functions listed above. When evaluating the-design from the standpoint of proper isolation postulated failure mechanisms of the nonsafety-related equipment were considered.

Recently,- Shoreham has conducted certain system interaction studies as required by the NRC which reconfirmedL(for the~ scope of L

Enclosure 1 Page 2 of 2 1

these studies) that the classification system provided proper isolation and separation between safety and nonsafety equipment.

' Two studies in particular are important in that respect. The Control Systems Failure (SCF) study and the High Energy Line

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Break / Control System Failure Analysis (HELB/CSFA) study examine the consequences of failure of nonsafety-related equipment.

. The CSF study examined those control grade (nonsafety) systems with the potential to affect reactor pressure, water level, or 1

power. Two possible failure mechanisms which could affect multiple control grade systems were postulated; failure of a common power supply or f ailure of a common impulse line. The study confirmed that, for all cases examined, previously defined transient and accident limits (Chapter 15 of the Shoreham FSAR) are bounding. The HELB/CSFA study addresses this concern even more directly. This study determined the hypothetical effect on nonsafety control systems resulting from postulated high energy line breaks. Once again it was concluded that previously defined accident and transient limits are bounding. Both of these studies envelope postulated failures resulting from adverse environmental conditions and further support LILCO's position on this issue.

The electrical isolation design philosophy at Shoreham provides an additional assurance that nonsafety-related electrical equipment cannot fail in such a manner as to prevent accomplishment of the above referenced safety functions. This design assurance also takes into consideration the single failure of a safety-related component. Shoreham's compliance with the electrical separation requirements of Regulatory Guide 1.75, Revision 1 and IEEE stan-dard 384-1975 is detailed in the FSAR, specifically, in answer to NRC requests 223.12 and 223.67. .These FSAR references demonstrate that the electrical separation design for the safety-related power circuits and control circuits is such that no single failure can prevent operation of an engineered safeguard function. Therefore, there is no single credible event which is capable of disabling sufficient equipment to prevent accomplishment of the.three basic safety functions described above.

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l ENCLOSURE 2 Review of Final EO Rule  ;

10CFR50.49 SECTION SHOREHAM EQ PROGRAM l

a. Applicant for a license shall establish The Qualification Program is established. .

an EQ Program for paragraph (b) equipment. I

b. Electric equipment important to safety must be addressed and includes: )

(b) (1) Qualify safety-related electric Shoreham EQ Program identified safety-equipment relied on to remain related equipment and assigned operability functional during and after design codes "A", "B", "C" and "D" as per NUREG-basis events to ensure: 0588, Appendix E, for LOCA and PBOC.

(i) integrity of pressure boundary (ii) shutdown plant (iii) limit offsite exposure (b) (2) Qualify nonsafety-related equip- Shoreham design precludes nonsafety-related ment whose failure, under postu- equipment preventing the accomplishment of lated environmental conditions, the three basic safety functions.

could prevent satisfactory accomplishment of safety functions (i) , (ii), and (iii) in (b) (1).

(b) (3) Qualify post-accident monitoring Equipment required for implementation of equipment. Reg. Guide 1.97, Rev. 2, is designated in LILCO submittal dated April 14, 1983, SNRC-863, Attachment C and qualification commitments are stated therein.

c. Requirements for (i) dynamic and seismic No new requirements defined in this rule.

qualification, (ii) protection against" "other" phenomena, and (iii) mild envi-ronment qualification not included in the scope of the final role.

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10CFR50.49 SECTION SHOREHAM EO PROGRAM d) Prepare list of important to safety equip- This is Appendix F of the Shoreham ment identified in (b) (1) , (b) (2) , and environmental Qualification Report. *

(b) (3) . ,

(d) (1) Performance specifications under Shoreham includes these requirements in ,

conditions during and following equipment documentation files.

design basis accidents.

(d) (2) Electrical characteristics to meet Shoreham includes these characteristics in performance requirements of (d) (1) . equipment documentation files.

(d) (3) Environmental conditions defined. Environmental conditions are defined by zone for equipment items.

e) Qualification program shall include assess- Shoreham EQ program complies.

ment of electric equipment to temperature, pressure, humidity, chemical effects, radiation, aging, submergence, synergistic effects, and margins.

f) Qualification methods defined for electric Shoreham EQ program complies.

equipment.

g) Holder of an operating license shall iden- All equipment will be qualified by the first tify equipment important to safety with refueling outage in accordance with this schedule for qualification by May 20, 1983. rule.

h) Notification to NRC of significant problems Shoreham will comply as required.

to meet EQ schedule.

i) Applicant for licenses shall submit interim This is Appendix H of the Shoreham Environ-justifications for equipment not qualified mental Qualification Report.

prior to fuel load.

j) Record qualification shall be maintained in Qualification document packages are included an auditable form, in Shoreham's document control system.

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10CFR50.49 SECTION SHOREHMi EQ PROGRM1 k) No requirement to requalify if NUREG 0588 Shoreham EQ program complies. ,

was the previous basis for qualificaticn. ,

1) Replacement equipment is required to be Shoreham EQ program complies. ,

qualified to final rule unless sound reasons to contrary exist.

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