Commonwealth Edison Co., (Zion Nuclear Power Station, Unit Nos. 1 and 2); Exemption

NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-295 and 50-304]

Commonwealth Edison Co., (Zion Nuclear Power Station, Unit Nos. 1

and 2); Exemption

I

Commonwealth Edison Company (ComEd or the licensee) is the holder

of Facility Operating License Nos. DPR-39 and DPR-48, which authorize

operation of the Zion Nuclear Power Station, Unit Nos. 1 and 2, at a

steady-state reactor power level not in excess of 3250 megawatts

thermal. The facilities are pressurized water reactors located at the

licensee's site in Lake County, Illinois. The licenses provide, among

other things, that the Zion Nuclear Power Station is subject to all

rules, regulations, and Orders of the U.S. Nuclear Regulatory

Commission (the Commission or NRC) now or hereafter in effect.

II

Sections III.C and III.D.3 of 10 CFR part 50, appendix J, option A,

require that Type C local leakage rate periodic tests shall be

performed during reactor shutdown for refueling, or other convenient

intervals, but in no case at intervals greater than 2 years. These

requirements are reflected in the Zion Technical Specifications (TS) as

requirements to perform Type C containment leakage rate testing in

accordance with 10 CFR part 50, appendix J, and approved exemptions.

III

The licensee has determined that certain containment isolation

pathways have not been locally leakage rate tested (Type C tests) as

required by option A of appendix J to 10 CFR part 50. In a letter dated

August 16, 1995, the licensee requested relief from the requirement to

perform the Type C containment leakage rate tests of certain

penetrations and valves in these pathways in accordance with the

requirements of sections III.C and III.D of 10 CFR part 50, appendix J,

option A. On August 16, 1995, the staff authorized in writing,

continued operation of the Zion units in a notice of enforcement

discretion (NOED) until such time as the

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staff acted on the exemption requests. In a letter dated November 20,

1995, the staff granted the schedular exemptions requested in the

licensee's letter of August 16, 1995, and granted schedular exemptions

for the permanent exemption requests to allow time for additional staff

review and until final staff action could be taken. In its letter of

November 28, 1995, and supplemented on December 6, 1995, the licensee

requested, in part, that certain schedular exemption requests be

granted as permanent exemptions. As requested, the staff granted

permanent exemptions for the containment isolation valves in

containment penetrations P-70 and P-99 by letter dated December 11,

1995.

The licensee's letter of November 28, 1995, also requested that the

following permanent exemption requests be changed to schedular

exemption requests.

Units 1 and 2: P-77, 1(2)PP0101, 1(2)PP0102, 1(2)PP0103,

1(2)PP0104, Penetration Pressurization to Containment Valve Stations;

and P-102, 1(2)AOV-RC8029, Primary Water to the Pressurizer Relief

Tank.

For Unit 1, the penetrations would be tested during the refueling

outage in the fall of 1995, and for unit 2, they would be tested during

the next cold shutdown of sufficient duration, and subsequently

thereafter as required. For P-77 and P-102, the staff's letter of

November 20, 1995, granted schedular exemptions until December 31,

1995. The final action for these penetrations is addressed below.

The licensee's letter of November 28, 1995, also requested that the

staff grant a schedular exemption for penetration P-44. In a letter

dated December 6, 1995, the licensee withdrew the request because it

had recently tested the penetration for both units 1 and 2 and intends

to continue to test the penetration in accordance with the requirements

of 10 CFR part 50, appendix J, option A.

The final resolution of the remaining issues is provided below.

Pathways Listed in Licensee's Letter Dated August 16, 1995

Attachment 2 of the licensee's letter of August 16, 1995, requested

permanent exemptions for components in the following containment

penetrations:

Units 1 and 2: P-14, Valve 1(2) FCV-SA01A, Service Air Supply to

Containment; P-19, Valve 1(2) MOV-CC9413A, Component Cooling Water

Supply to the Reactor Coolant Pumps; P-34, Valve 1(2) DW0030,

Demineralized Flushing Water to Containment; P-43, Valve 1(2) LCV-

DT1003, Reactor Coolant Drain Tank Pump Discharge; P-75, Valves 1(2)

VC8402A, 1920HCV-VC182, 1(2) VC8402B, 1(2) VC8403, Chemical and Volume

Control to Regenerative Heat Exchanger; P-76, Valve 1(2) VC8480A,

Reactor Coolant Loop Fill Header; P-77, Valves 1(2) PP0101, 1(2)

PP0102, 1(2) PP0103, 1(2) PP0104, Penetration Pressurization to

Containment Valve Stations; P-88, Valve 1(2) FCV-RV112, Containment Hot

Water Supply; and P-102, Valve 1(2) AOV-RC8029, Primary Water to the

Pressurizer Relief Tank.

Unit 1 only: P-16, Compression Fittings on Five Reactor Vessel Leak

Detection System Lines.

As stated above, the requests for P-77 and P-102 were changed from

permanent to schedular exemptions.

Also, in attachment 3 of the licensee's letter of August 16, 1995,

the licensee requested staff concurrence concerning certain

clarifications for the testing of P-23, P-44, and P-66.

Schedular Exemptions

As requested, penetrations P-77 and P-102 will receive extensions

of the schedular exemptions granted on November 20, 1995, rather than

permanent exemptions. For Unit 1, the penetrations were tested during

the refueling outage which concluded on December 17, 1995, and will be

tested hereafter as required by Appendix J, Option A, so no further

exemption is needed. For Unit 2, they will be tested during the next

cold shutdown of sufficient duration (no later than the next refueling

outage), and subsequently thereafter as required. The staff's review

and justification for the schedular exemptions granted for these

penetrations on November 20, 1995, remains valid and will not be

repeated here. The staff finds that, on the basis stated in the

November 20, 1995, exemption, it is acceptable to delay the testing of

P-77 and P-102 until the next cold shutdown of sufficient duration, but

no later than the next refueling outage, for Unit 2. The next Unit 2

refueling outage is currently scheduled for September 1996. Further,

the staff finds that the special circumstances required by 10 CFR

50.12(a)(2)(v) are present as described in the November 20, 1995

exemption, namely, that the requested exemptions provide only temporary

relief and the licensee made good faith efforts to comply.

Permanent Exemptions

The licensee has requested permanent exemptions for several

penetrations because it is not possible to perform the required testing

with the current hardware configurations, such as the absence of test

taps or block valves that would be needed to perform the tests. In each

case, the relief is not from testing through-valve leakage paths, but

rather leakage paths out of containment isolation valves through valve

packing, diaphragms, or compression fittings. The permanent exemption

requests may be divided into three groups, as follows:

1. P-14: The licensee proposes to test the valve packing by

pressurizing it with air to a pressure greater than or equal to Pa

and performing a soap bubble test on the packing, with an acceptance

criterion of zero observed bubbles. This will be done at the normal

Type B and C testing frequency; further, the test was performed and

passed during the recent Unit 1 refueling outage and during January

1995 for Unit 2. Generally, a soap bubble test cannot be used to

quantify a leakage rate, which is required by the regulation, but when

the observed leakage is zero (no bubbles being produced), then the

leakage rate is also zero. Therefore, the proposed testing method in

fact complies with the requirements of Appendix J, Option A, and no

exemption is required.

2. P-19, P-34, P-43, P-75, P-76, P-88: In each case, the licensee

proposes to test the valve packing (or, in the case of P-43, the valve

diaphragm) by pressurizing it with water to a pressure greater than or

equal to 1.1 Pa and then visually examining the packing or

diaphragm for water leakage, with an acceptance criterion of zero

observed leakage. This will be done at the normal Type B and C testing

frequency. The significant difference between these penetrations and P-

14 is the use of water instead of air as the test medium. The proposed

test, with water as the test medium and with a zero leakage acceptance

criterion, is conservative enough to provide reasonable assurance of no

significant increase in risk to health and safety of the public when

compared to testing with air, especially when considering the nature of

the potential leakage paths. The leakage pathways do not consist of

through-valve leakage paths, but rather leakage paths out of

containment isolation valves through valve packing or diaphragms. The

potential leakage paths are small or restrictive, through packing

openings or through cracks or tears in valve diaphragms. The leakage

path for a significant leak to occur also requires a sequence of events

for which the probability of occurrence is low, as detailed in the

licensee's letter of August 16, 1995. In addition, for some of the

systems, seismic support and the isolation valve seal water system

provide additional assurance that the risk of a significant leak is

minimal.

[[Page 418]]

Therefore, the proposed testing provides an acceptable alternative to

the requirements of Appendix J, Option A.

3. P-16 (Unit 1 only): The licensee proposes to test the

compression fittings on five small lines by pressurizing them with air

to a pressure greater than or equal to Pa and performing a soap

bubble test on the fittings, with an acceptance criterion of zero

observed bubbles. However, these lines cannot be locally pressurized to

the test pressure, so this will be done only during Type A tests, which

are required at a frequency of 3 times in 10 years, instead of the Type

B and C testing interval (every refueling outage, but not to exceed 2

years). The staff will accept the proposed testing frequency because

Type A test history at Zion Station has shown that this type of fitting

has not been problematic. Further, these particular fittings have never

caused a Type A test failure by leaking excessively. As such, the staff

does not expect the lesser testing frequency to significantly impact

the leak-tightness of the containment boundary. However, this exemption

is applicable only to Option A of Appendix J. If the licensee adopts

Option B of Appendix J for containment leakage rate testing at Zion

Unit 1, the exemption for P-16 is hereby revoked and the matter will

have to be reexamined under the requirements of Option B.

Clarifications for P-23, P-44, and P-66

P-23: 1(2) MOV-CC9414, CC Return from the RPC Lube Oil Coolers.

The licensee requested staff concurrence that this valve is a

single barrier and that the Type C test performed on the outboard disk

is adequate. As stated in the staff's Request for Additional

Information letter of December 11, 1995, the staff concurs with the

licensee.

P-44: 1(2) PR0029, Containment Sping Return Line to the

Containment.

As stated above, the licensee withdrew its request and will test

the penetration in accordance with Appendix J, Option A.

P-66: Reactor Coolant Pump Seal Injection System.

The licensee requested staff concurrence that the subject system

may be considered a qualified water seal system for penetration P-66.

In its letter of November 28, 1995, the licensee provided additional

details as to the procedural requirements and the time frames involved

in the switch over from the injection phase to cold leg recirculation

using the containment sump as a water supply. The additional

information indicates that, although there may be a brief interruption

in sealing water pressure during switch over, the water-sealing action

of the system would be essentially continuous throughout the 30-day

post-accident period. Therefore, the staff concurs that the subject

system may be considered a qualified water seal system for penetration

P-66.

To justify granting an exemption to the requirements of 10 CFR Part

50, Appendix J, Option A, a licensee must show that the requirements of

10 CFR 50.12(a)(1) are met. The licensee stated that all its exemption

requests meet the requirements of 10 CFR 50.12(a)(1), for the following

reasons:

Criteria for Granting Exemptions are Met Per 10 CFR 50.12(a)(1)

1. The requested exemptions and the activities which would be

allowed thereunder are authorized by law.

If the criteria established in 10 CFR 50.12(a) are satisfied, as

they are in this case, and if no other prohibition of law exists to

preclude the activities which would be authorized by the requested

exemption, and there is no such prohibition, the Commission is

authorized by law to grant this exemption request.

2. The requested exemption will not present undue risk to the

public.

As stated in 10 CFR 50, Appendix J, Option A, the purpose of

primary containment leak rate testing is to assure that leakage

through primary containment and systems and components penetrating

primary containment shall not exceed the allowable leakage rate

values as specified by the Technical Specifications or associated

bases and to ensure that the proper maintenance and repairs are made

during the service life of the containment and systems and

components penetrating primary containment. The requested exemption

is consistent with this intent for those penetrations in that

alternate means of ensuring leakage remains acceptably low will be

performed as proposed herein.

3. The requested exemption will not endanger the common defense

and security.

The common defense and security are not in any way compromised

by this exemption request.

In addition, the licensee must show that at least one of the

special circumstances, as defined in 10 CFR 50.12(a)(2) is present. One

of the special circumstances that a licensee may show to exist is that

the application of the regulation in the particular circumstance is not

necessary to achieve the underlying purposes of the rule. The purposes

of the rule, as stated in Section I of 10 CFR 50, Appendix J, Option A,

are to ensure that: (1) Leakage through the primary reactor containment

and systems and components penetrating containment shall not exceed

allowable values, and (2) periodic surveillance of reactor containment

penetrations and isolation valves is performed so that proper

maintenance and repairs are made. The staff has reviewed the licensee's

proposal and has concluded for the reasons discussed above that the

proposed alternative tests will confirm the integrity of the subject

pathways. Therefore, application of the regulation in this particular

circumstance is not necessary to achieve the underlying purpose of the

rule.

IV

Sections III.C and III.D.3 of 10 CFR Part 50, Appendix J, Option A,

require that Type C local leak rate periodic tests shall be performed

during reactor shutdown for refueling, or other convenient intervals,

but in no case at intervals greater than 2 years.

The licensee proposes exemptions to these sections which would

provide relief from the requirement to perform the Type C containment

leak rate tests of certain valves in accordance with the requirements

of Sections III.C and III.D of 10 CFR Part 50, Appendix J, Option A.

The Commission has determined that, pursuant to 10 CFR 50.12(a)(1),

this exemption is authorized by law, will not present an undue risk to

the public health and safety, and is consistent with the common defense

and security. The Commission further determined that special

circumstances, as provided in 10 CFR 50.12(a)(2) (ii), or (v) are

present justifying the exemption; namely, that the application of the

regulation is not necessary to achieve the underlying purpose of the

rule; or the exemptions provide only temporary relief and the licensee

made good faith efforts to comply.

Therefore the Commission hereby grants the following exemptions:

The requirement of 10 CFR Part 50, Appendix J, Option A, to

perform Type C local leakage rate periodic tests of penetrations P-

77 and P-102 at intervals no greater than 2 years is not required.

For P-77 and P-102, for Unit 1, the penetrations were tested during

the Unit 1 refueling outage in the fall of 1995, and for Unit 2,

they will be tested during the next cold shutdown of sufficient

duration, but no later than the next refueling outage and

subsequently thereafter as required.

The requirement of 10 CFR Part 50, Appendix J, Option A, to test

penetrations P-19, P-34, P-43, P-75, P-76, and P-88 for Units 1 and

2 with air is not required. Instead, the test pressure medium may be

water. These tests will be performed at the normal Type B and C

testing frequency.

The requirement of 10 CFR Part 50, Appendix J, Option A, to test

penetration P-16 for Unit 1 at intervals no greater than 2 years is

not required. Instead, this penetration may be tested during Type A

tests, which are required 3 times at approximately equal intervals

each 10 year

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service period. However, if the licensee adopts 10 CFR Part 50,

Appendix J, Option B, for containment leakage rate testing at Zion,

Unit 1, with the potential for Type A test intervals of 10 years,

the exemption for P-16 is hereby revoked.

Pursuant to 10 CFR 51.32, the Commission has determined that

granting these exemptions will not have a significant impact on the

human environment (60 FR 45499).

Dated at Rockville, Maryland, this 28th day of December 1995.

For the Nuclear Regulatory Commission.

Gail Marcus,

Acting Director, Division of Reactor Projects--III/IV, Office of

Nuclear Reactor Regulation.

[FR Doc. 96-146 Filed 1-4-96; 8:45 am]

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