ML20138B156

Permanent Exemptions Re Types a & C Leak Testing

ML20138B156
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	03/31/1986
From:	CONNECTICUT YANKEE ATOMIC POWER CO.
To:
Shared Package
ML20138B132	List: B11994, Requests Exemption from Requirements of App J to 10CFR50. Util Has Initiated Detailed Evaluation of Scope & Schedule for Mods Required to Achieve Compliance W/App J as Part of Facility Isap ML20138B156 ML20138B183 ML20138B200
References
NUDOCS 8603200291
Download: ML20138B156 (8)

Text

O 1 Docket No.-50-213 ATTACHMENT 1 HADDAM NECK PLANT PERMANENT EXEMPTIONS RELATED TO TYPES A AND C LEAK TESTING 8603200291 DR 860312 p ADOCK 05000213 PDR l-1 March 1986

1.0 GENER AL DISCUSSION OF REQUESTS FOR PERMANENT EXEMPTIONS 1.1 Introduction In response to an NRC request dated January 2,1975(l), Connecticut Yankee Atomic Power Company (CYAPCO), submitted proposed changes to the Haddam Neck Plant he requirementsTechnical of 10CFR50,Specifications' Appendix 3. which were intended Subsequently, on May to 28,implement 1975t }2),

CYAPCO requested exemptions from certain of the requiremen}s o Appendix 3.

These exemption requests were later supplemented and modifiedl3-9. On May 7, 1982(10), the NRC Staff issued Amendment 49 to Facility Operating License No.

DPR-61 for the Haddam Neck Plant, which issued revised Technical Specifica-tions reflecting the requirements of Appendix 3.

CYAPCO has recently completed a comprehensive review of the status of compliance with Appendix 3 for the Haddam Neck Plant. As a result of this review, CYAPCO is requesting certain permanent exemptions from the requirements of Appendix 3. In light of the attached justifications for the proposed exemptions, CYAPCO believes that adequate basis exists for granting the requested exemptions.

1.2 Exemption Criteria The Commission's regulations, specifically,10 CFR 50.12(a), provide that exemp-tions may be granted from the regulations in 10 CFR 50 provided that they are

" authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest." On December 12, 1985, the Commission published the final revisions to 10 CFR 50.12(a), regarding standards to be applied in granting exemptions (50 Federal Register 50764, December 12,1985). The purpose of the final rule was to revise and clarify the criteria for granting exemptions. CYAPCO's requests for exemptions are based on the revised 10 CFR 50.12(a), which became effective January 13,1986. An evaluation of each of the exemptions requested by CYAPCO is presented in the following sections of this attachment.

Based on the information provided in subsequent sections of this attachment, CYAPCO concludes that exemptions from the requirements of 10 CFR 50, Appendix 3 are justified pursuant to paragraph 50.12(a)(2)(ii) of the final rule.

That is, they are:

Authorized by law; Will not present undue risk to public health and safety; and Are consistent with the common defense and security.

Additicnally, application of the regulation in the particular circumstances would not serve the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule.

In general, the intent of the Commission's regulations and other NRC require-ments is to provide reasonable assurance that operation of nuclear power plants does not pose an undue risk to the health and safety of the public. The intent of specific regulations, such as Appendix J, is to set standards which will provide 1-2

reasonable assurance that the individual contributions to risk posed by specific issues or concerns will be low, such that overall plant risk remains acceptably low. While compliance with the regulations will, for the most part, provide reasonable assurance that plant operation does not pose undue risk to the health and safety of the public, noncompliance does not necessarily represent an unacceptable risk.

In the specific case of the Commission's requirements regarding containment leak rate testing, the underlying purpose of these requirements is to assure that any radioactive materials released into the containment during a postulated loss-of-coolant accident will be suitably contained and that release to the outside environment will be small, i.e., that the risk associated with such releases is low. Granting the requested exemptions will not result in an increase in the risk associated with containment leakage, as demonstrated in subsequent sections of this attachment.

1.3 Conclusion In summary, CYAPCO has concluded that exemptions from the requirements of Appendix 3 for those areas discussed in the following sections of the attachment are warranted, pursuant to 10 CFR 50.12(a)(2)(ii).

1.4 References (1) E. 3. Brunner letter to D. C. Switzer, dated January 2,1975, " Inspection Report No. 50-213/74-15."

(2) D. C. Switzer letter to R. A. Purple, dated May 28,1975, " Exemption from the Provisions of 10CFR50, Appendix 3."

(3) D. C. Switzer letter to R. A. Purple, dated August 20,1976, (Special Report re. Containment Operation and Testing).

(4) D. C. Switzer letter to A. Schwencer, dated December 27, 1976,

" Containment Leak Rate Testing."

(5) D. C. Switzer letter to A. Schwencer, dated August 8,1977, " Proposed Exemptions to 10CFR50 Appendix 3."

(6) D. C. Switzer letter to A. Schwencer, dated September 19,1977, " Proposed Exemptions to 10CFR50 Appendix 3."

(7) W. G. Counsit letter to D. L. Ziemann, dated June 12,1978, " Proposed Exemptions to 10CFR50 Appendix 3."

(8) W. G. Counsil letter to D. L. Ziemann, dated November 13,1978, " Proposed Exemptions to 10CFR50 Appendix 3."

(9) W. G. Counsil letter to D. L. Ziemann, dated July 24,1979, " Proposed Exemptions to 10CFR50 Appendix 3."

(10) D. M. Crutchfield letter to W. G. Counsil, dated May 7,1982, " Appendix 3 Requirements (Containment Leakage Testing)."

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2.0 EXEMPTIONS REQUESTED 2.1 Exemption from the Requirements of Section III.A.4.(a) of Appendix'3

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2.1.1 Exemption Requested .

Section III.A.4.(a) of Appendix 3 to 10 CFR 50 states:

"An initial test shall be performed at a pressure P ts not less than 0.50 Pa to measure a leakage rate Ltm."

i While the applicability of this provision is arguable as previously described (9),

CYAPCO hereby requests an exemption from the requirement of Appendix 3 that Pt equal 0.50 Pa- .The exemption would permit CYAPCO to continue testing

] the Haddam Neck Plant at a Pt of 15 psig.

2.1.2 Description

)r During preoperational testing (1967) at the Haddam Neck Plant, integrated leak

rate tests (ILRT) were performed at the design pressure of 40 psig and at a reduced pressure of 15 psig (Pt ); at that time, the calculated peak accident

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pressure (Pa) for the Haddam Neck Plant was 30 psig (Reference 4).

, As a result of subsequent analytical efforts, such as environmental qualification

' for safety-related electrical equipment at the Haddam Neck Plant (Reference 2),

CYAPCO generated new temperature and pressure profiles for both the LOCA and main steam line break. The calculated peak pressure was determined to be approaching 40 psig, which represents a 10 psig increase in the originally calculated accident pressure of 30 psig. Although the peak accident pressure has changed, CYAPCO has continued to perform periodic testing at the Haddam l Neck Plant at a reduced pressure (Pt ) of 15 psig.

Although the NRC Staff issued revised Technical Specifications for the Haddam

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. Neck Plant which clearly designated Pa as 40 psig and Pt as 15 psig (Reference 1), in a January 17, 1985 letter (Reference 7), the NRC requested l CYAPCO to enhance its efforts to maintain containment integrity during the

] upcoming refueling cycle by responding to several items, which included opening a dialogue with the NRC regarding test pressure and reduced test pressure

, leakage correlations. CYAPCO believes that such a dialogue has been ongoing as

reflected by its previous submittals on this issue (References 4, 5 and 8).

i However, the following discussion is provided to summarize CYAPCO's position j on the ILRT requirements for the Haddam Neck Plant.

i CYAPCO has reviewed the basis for reduced pressure testing at the Haddam i Neck Plant and, as outlined below, CYAPCO concludes that the reduced pressure j testing program utilized at the Haddam Neck Plant is acceptable and represents

a technically supportable method of confirming containment integrity. This j position is based on the following:

o CYAPCO's 1967 preoperational test results satisfactorily j demonstrated that reduced pressure testing can be

accomplished which correlates well with the results of a i

full pressure test. CYAPCO has reviewed the suitability

) of the reduced test pressure of 15 psig (Reference 6) via J

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correlation of leakage values at 40 psig and 15 psig, under 10 CFR 50, Appendi_x 3 criteria. The correlation is docu-mented in Technical . Specification 4.4.1.B.2 and 10 CFR 50, Appendix 3, Ill.A.4(a)(1)(iii). CYAPCO has submitted proposed changes to Technical Specifications on several occasions (Reference 8), reflecting the method by which the Haddam Neck Plant addresses Appendix 3.

CYAPCO has shown that reduced pressure testing (at 15 psig) is sufficient to produce the conditions necessary to cause measurable changes in containment air mass, 1 over time. ILRT verification tests have shown acceptable l results, further demonstrating suitability of reduced pres-sure testing.

o Section Ill.A.4(a)(1)(i) of Appendix 3, regarding preopera-tional testing, defines the reduced test pressure (Pt ) for Type A testing as one-half of the accident pressure (Pa)-

The reduced test pressure of 15 psig corresponded to one-half of the calculated accident pressure at the time Haddam Neck's preoperational testing was performed.

2.1.3 Justification for Exemption The requested exemption will present no significant hazard to the health and safety of the public for the following reasons:

1. The current Type B and C testing programs provide overall assurance that postulated offsite ~ dose consequences resulting from a design basis accident would be within the limits of 10 CFR 100. For this reason, the Type A test is intended to be an operational and functional check of the entire primary containment isolation system. CYAPCO's current program meets the intent of Appendix 3 by accomplishing testing which locates, quantifies and initiates repair of containment leakage sources.

2. The preoperational Type A tests at 15 psig and 40 psig were conducted to evaluate whether a correlation could be established that would allow reduced pressure testing for periodic tests. The important factor here is not that Pt is one-half of Pa, but that a correlation is demon-strated which will allow a reduced pressure to be used without compromising public safety. CYAPCO believes that this goal has been accomplished and that a Type A test at P t is a valid method of ensuring public safety during a Pa accident.

3. If CYAPCO were to begin testing at 20 psig, a 40 psig ILRT would likely have to be conducted following the initial 20 psig test. This test would verify that a correlation exists between the 20 psig and 40 psig ILRTs and that future 20 psig ILRTs will establish the 1-5

containment's integrity at Pa. Since an ILRT involves one week during an outage, the current projected cost of performing a 40 psig ILRT is $3,200,000 for replacement power and $60,000 for the test itself (Reference 4). Since the current P tof 15 Psig is an assurance of public safety during a postulated Pa accident, CYAPCO contends that i

this additional cost would result in no additional signifi-cant improvement in public safety and, therefore, is not justified.

I Based on the above information, CYAPCO concludes that the requested exemption is warranted.

2.1.4 References

1. R.A. Purple letter to D.C. Switzer, dated May 20,1975 (issued Ammend-ment No. 2 to Facility License No. DPR-61).

2. W.G. Counsil letter to D.M. Crutchfield, dated April 1,1981, " Environ-mental Qualification of Electrical Equipment."

3. D.M. Crutchfield letter to W.G. Counsil, dated July 23,1982, " Containment Pressure During a Loss-of-Coolant Accident (LOCA)."

4. W.G. Counsil letter to T.E. Murley, dated October 19, 1984, "1984 Appendix 3 Type A Test."

5. W.G. Counsil letter to T.E. Murley, dated October 24, 1984, "1984 Appendix 3 Type A test."

6. W.G. Counsil letter to T.E. ' Murley, dated November 2, 1984, "1984 Appendix 3 Type A Test."

7. T.T. Martin letter to W.G. Counsil, dated January 17,1985 (Inspection Report No. 50-213/84-25).

8. W.G. Counsil letter to T.E. Murley, dated January 31, 1985,"1984 Appendix 3 Type A Test."

9. J. F. Opeka letter T. E. Murley, dated December 23,1985, "10CFR 50, Appendix 3 Compliance."

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2.2 Exemption from the Requirements of Section II.H of Appendix 3 2.2.1 Exemption Requested Section II.H of 10 CFR 50, Appendix 3 requires that Type C tests be performed for containment isolation valves that:

"1. Provide a ~ direct connection between the inside and out-side atmospheres of the primary reactor containment under normal operation, such as purge and ventilation, vacuum relief, and instrument valves;

2. Are required to close automatically upon receipt of a containment isolation signal in response to controls intended to effect containment isolation;

3. Are required to operate intermittently under postaccident conditions; and

4. Are in main steam and feedwater piping and other systems which penetrate containment of direct-cycle boiling water power reactors."

CYAPCO requests exemption from the Type C testing requirements of Section II.H. of Appendix 3 for the steam generator blowdown (P-15,16,17,18), and auxiliary feedwater (P-81) penetrations.

2.2.2 Justification for Exemption Section II.H.4 of Appendix 3 does not require that the main steam and feedwater systems in PWRs be Type C tested. These systems are not directly connected to the reactor coolant system and are not postulated to rupture as a result of a loss-of-coolant accident (LOCA). Consequently, these systems do not experience post-LOC A leakage of containment atmosphere. Further, CY APCO has imple-mented post-accident emergency procedures to maintain steam generator water level above the tube bundle and to pressurize the secondary side to a pressure greater than Pa as soon as practical following the onset of a postulated LOCA.

The steam generator blowdown (P-15,16,17, and 18) and auxiliary feedwater (P-81) penetrations are not connected to the reactor coolant system and are not relied upon to prevent the escape of containment air following a postulated LOCA, Consistent with the application of Section II.H.4 to the main steam and feedwater penetrations (P-42 through P-49) at the Haddam Neck Plant, CY APCO maintains that the steam generator blowdown and auxiliary feedwater penetra-tions should be permanently exempt from Type C testing.

2.3 Exemption from the Requirements of Section III.C.1 of Appendix 3 2.3.1 Exemption Requested Section Ill.C.1 of Appendix 3 to 10 CFR 50 states:

" Type C tests shall be performed by local pressurization.

The pressure shall be applied in the same direction as that 1-7

when the valve would be required to perform its safety function, unless it can be determined that the results from ~ the tests for a pressure applied in a different direction will provide equivalent or more conservative results."

CYAPCO requests an exemption from the above requirement so that valves in the auxiliary spray penetration (P-80) may be tested in the reverse direction:

2.3.2 3ustification for Exemptions The auxiliary spray (P-80) penetration is isolated by motor-operated valve RH-MOV-31 which is tested in the reverse direction. Piping associated with this penetration is pressurized by the fire water system at a minimum pressure of 80 psig. The~ fire water system uses the Conhecticut River as its source of water, and the system pumps have a capacity of 2900 gpm at 100 psig. The system is comprised of an electric driven pump with a backup diesel driven pump; the status of the pumps is provided in the control room, and the pumps may be operated from the control room. The fire water system is maintained in accordance with the quality assurance requirements of the fire protection program. System pressure is normally controlled at 100 to 110 psig by a hydropneumatic pressure maintenance system.

While the yard piping loop is a single line, sectionalizing valves are provided to permit partial line isolation without interruption of service to the entire system.

Thus, a pressure at least double accident pressure (Pa) is reliably maintained in' this piping, which would assure that the valves in this penetration are not i

exposed to containment atmusphere leakage. Although this penetration is not

sealed by an installed seal system, the penetration is effectively sealed by the system itself, and water testing of this penetration at a pressure not less than 1.1 Pa is appropriate. Further, reverse direction testing of this penetration is appropriate since post-accident leakage would tend to occur into the containment. On this basis, CYAPCO believes that a permanent exemption from the requirements of Appendix 3 to permit reverse direction testing of Penetration P-80 is justified; based upon demonstration of an effective 30-day

water seal, no exemption is required to test this penetration with water.

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