[Federal Register Volume 62, Number 197 (Friday, October 10, 1997)]
[Notices]
[Pages 53029-53031]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-26991]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-255]


In the Matter of Consumers Energy Company (Palisades Plant); 
Exemption

I

    Consumers Energy Company (the licensee) is the holder of Facility 
Operating License No. DPR-20 which authorizes operation of the 
Palisades Plant. The Palisades facility is a pressurized-water reactor 
located at the licensee's site in Van Buren County, Michigan. The 
license provides, among other things, that the facility is subject to 
all rules, regulations, and orders of the Commission now or hereafter 
in effect.

II

    Pursuant to 10 CFR 50.12(a), ``Specific exemptions,'' the 
Commission may grant exemptions from the requirements of the 
regulations of this part (1) which are authorized by law, will not 
present an undue risk to the public health and safety, and are 
consistent with the common defense and security; and (2) where special 
circumstances are present.
    Section II.G. of 10 CFR Part 50, Appendix J, Option A, defines Type 
B tests as ``tests intended to detect local leaks and to measure 
leakage across each pressure-containing or leakage-limiting boundary * 
* *.'' which includes air lock door seals.
    Section III.D.2.(b)(ii) of 10 CFR Part 50, Appendix J, Option A, 
requires air locks opened during periods where containment integrity is 
not required to undergo a full air lock pressure test at the end of 
such periods.
    Section III.D.2.(b)(iii) of 10 CFR Part 50, Appendix J, Option A, 
requires air locks opened during periods where containment integrity is 
required to undergo a full air lock pressure test within 3 days after 
being opened.

III

    By letters dated January 10, 1996, and February 20, 1997, the 
licensee requested an exemption from 10 CFR Part 50, Appendix J, Option 
A, Sections III.D.2.(b)(ii) and III.D.2.(b)(iii), for Type B testing of 
the emergency escape air lock. Specifically, this exemption would 
permit the licensee to perform a door seal contact verification check 
in lieu of the final pressure test required by Appendix J following 
opening the air lock doors for post-test restoration or seal 
adjustment.
    The exemption request is necessary due to the original design of 
the emergency escape air lock. During special testing in 1992, the 
licensee showed that the annulus between the door seals could not be 
successfully tested without the door strongback installed even at 
pressures as low as 2 psig. This testing, along with information from 
the vendor, confirms that between-the-seal pressure testing on the 
emergency escape air lock doors cannot be properly measured or 
evaluated if the door strongbacks are not installed. Similarly, the 
inner door does not fully seal with the reverse-direction pressure of a 
full air lock pressure test unless the strongback is installed.
    Since the removal of the inner door strongback after pressure 
testing requires the outer door to be opened, a between-the-seals test 
of the outer door would be required by the regulation. This test would 
require the installation of a strongback on the outer door. Further, 
full pressure testing or the pressure induced by the strongback may

[[Page 53030]]

cause the seals to take a set. It is therefore necessary to open both 
doors (one at a time) after any pressure testing to ensure full seal 
contact, and there is a potential need to readjust the seals to restore 
seal contact.
    As an alternative to a final pressure test required by Appendix J 
for verification of door seal functionality, the licensee has proposed 
a final door seal contact verification. This seal performance 
verification is completed following the full pressure air lock test, 
after the removal of the inner door strongback, and just prior to final 
closure of the air lock doors. The requested exemption would not affect 
compliance with the present requirement to perform a full pressure 
emergency escape air lock test at 6-month intervals. It would also not 
affect the requirement to perform a full pressure emergency escape air 
lock test within 72 hours of opening either door during periods when 
containment integrity is required. The seal contact check replaces the 
pressure test required by Appendix J for the door opening(s) and/or 
seal adjustments associated with restoration from the required full 
pressure tests.
    The licensee has performed additional low pressure between-the-
seals testing on the escape lock door seals to measure seal leak rates 
at low initial pressures and without the door strongbacks installed, to 
see if such tests would yield useful results. The tests indicated that 
meaningful between-the-seals testing is not possible with the present 
design of the escape air lock, without strongbacks installed.
    The licensee has also considered possible modifications to the 
existing emergency escape air lock doors in an attempt to identify 
other methods of complying with the Appendix J requirements. The 
modifications that were considered were:

1. Modify the Seal Design or Change the Seal Material

    A proposal was received from the air lock vendor to perform testing 
of different seal shapes and materials. This was later withdrawn. The 
vendor believes, and the licensee concurs, that the seal material and 
shape currently in use are reliable and adequate to maintain 
containment integrity. Simply changing the seal material or shape would 
be unlikely to allow meaningful between-the-seals tests with 
strongbacks removed.

2. Perform Door Modifications by Removing the Doors and Altering the 
Sealing Surfaces

    Minor modifications were considered for the door mechanisms in 
conjunction with reconfigured sealing surfaces. This modification has 
never been performed by the air lock vendor and would be experimental. 
There is no guarantee that these efforts would be successful in 
allowing Palisades to perform between-the-seals testing. The cost of 
this modification is estimated by the licensee to be roughly equal to 
performing an air lock retrofit, as described below.

3. Perform an Air Lock Retrofit Which Would Include Removing and 
Replacing the Doors, the Ends of the Bulkhead, and the Door Mechanisms

    The doors would be replaced with doors of a design whose seals can 
be tested per Appendix J without additional restraint or subsequent 
seal restoration. The mechanisms would be updated for smoother 
operation but their function would not be altered.
    The only viable alternative found was the replacement of the air 
lock doors, which the licensee has estimated would cost a minimum of 
$700,000. The licensee states that the cost of performing the 
modification is not warranted because no increase in plant or public 
safety would be realized. The other modifications to the present doors 
or seals would not ensure adequate performance improvement for 
unrestrained between-the-seals testing.
    During its review, the staff questioned whether post-test seal 
adjustment or ``fluffing'' was necessary because the door seals were 
too old or worn out to rebound properly to their original shape after 
leakage rate testing or whether past fluffing had damaged the seals, 
such that replacement of the seals could result in acceptable between-
the-seals testing. The licensee's response, dated February 20, 1997, 
stated that the seals are replaced approximately every 3 years and that 
the seals have not exceeded their service lives. Also, the licensee 
stated that fluffing has not damaged the seals, as indicated by 
continued successful Type B tests on both the emergency escape air lock 
and on the personnel air lock, on whose seals fluffing is also 
performed.
    The licensee's proposed test methods deviate from the requirements 
of Appendix J in two ways:
    (1) The seals are not leakage rate tested after opening the doors 
for post-test restoration, such as removing the strongbacks; and
    (2) The seals are not leakage rate tested after being adjusted 
(e.g., fluffed).
    The following quotation from American National Standard ANSI/ANS-
56.8-1994, ``Containment System Leakage Testing Requirements,'' is 
pertinent. Section 3.3.4.2 states, in part:

    An airlock test shall be performed whenever repairs or 
adjustments have been performed that affect the leakage rate 
characteristics of the airlock. Opening of the airlock for the 
purpose of removing airlock testing equipment following an airlock 
test does not require further testing of the airlock.

    The quoted provisions have been endorsed by the staff through 
Regulatory Guide 1.163, ``Performance-Based Containment Leak-Test 
Program,'' dated September 1995, for plants following Option B of 
Appendix J. Although Palisades follows Option A of Appendix J for Type 
B and C leakage tests, in this case the quoted provisions represent a 
valid technical position that may be used to help establish a basis for 
granting an exemption from the requirements of Option A of Appendix J.
    Therefore, concerning deviation (1) described above, the staff's 
technical position is that leakage rate testing is not necessary after 
opening the doors for post-test restoration. Option A of Appendix J 
requires a leakage rate test after opening a door, with the idea that 
the door opening is a relatively isolated event. Requiring another test 
immediately after a valid test simply because the door was opened again 
to remove test equipment is not necessary to meet the intent of the 
regulation, especially if it leads to an infinite series of tests, as 
in this case. Thus, deviation (1) is acceptable as part of an exemption 
from Option A of Appendix J.
    Concerning deviation (2) above, there is considerable evidence that 
post-test seal adjustment should not necessitate a follow-up leakage 
rate test in this case. The present practice ensures proper door seal 
contact prior to final door closure. The performance of this door seal 
contact check has led to the successful completion of subsequent 
emergency escape air lock full pressure tests since the procedural 
practice began in 1987. Also, no ILRT in that period has failed because 
of emergency escape air lock door seal leakage. Based on these results, 
the air lock doors have been proven to function as designed using 
current methods of testing and maintenance, including seal contact 
checks. Alternatives would only provide approximately the same level of 
protection for public health and safety as currently exists. Continuing 
with the current methods of testing will not result in undue risk to 
public health and safety and is consistent with the common defense and 
security. Further,

[[Page 53031]]

the underlying purpose of between-the-seals testing is to verify the 
seal integrity after an air lock door is opened or its seals adjusted. 
The seal contact check performed on the emergency escape air lock door 
seals serves this purpose and ensures the doors are sealing properly. 
Therefore, application of the regulation to perform between-the-seals 
leakage rate tests after seal adjustment is not necessary in this case 
to achieve the underlying purpose of the rule.

IV

    Accordingly, the Commission concludes that the licensee's proposal 
to perform seal contact testing instead of Type B leakage rate between-
the-seals testing on the emergency escape air lock door seals is 
acceptable. There is reasonable assurance that the containment leakage 
limiting function will be maintained.
    The licensee's request cites the special circumstances of 10 CFR 
50.12, Sections (a)(2)(ii) and (a)(2)(iii), as the basis for the 
exemption. Appendix J to 10 CFR Part 50 requires full pressure tests 
following air lock door openings. The licensee stated that the proposed 
alternate seal contact verification check will ensure that the air lock 
doors are sealing properly. The licensee also stated that the only 
viable alternative to the proposed exemption would be to perform an air 
lock retrofit that would involve a significant cost to the licensee. 
The Commission concludes that the special circumstances of 10 CFR 
50.12(a)(2)(ii) are present in that application of the regulation in 
these particular circumstances is not necessary to achieve the 
underlying purpose of the rule.

V

    Accordingly, the Commission has determined, pursuant to 10 CFR 
50.12(a), that 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 determines that 
special circumstances as provided in 10 CFR 50.12(a)(2)(ii) are present 
justifying the exemption.
    Therefore, the Commission hereby grants the exemption from 10 CFR 
Part 50 Appendix J, Option A, Sections III.D.2.(b)(ii) and 
III.D.2.(b)(iii), to the extent that leakage rate testing is not 
necessary after opening the emergency escape air lock doors for post-
test restoration or post-test adjustment of the airlock door seals.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will not have a significant effect on the 
quality of the human environment (62 FR 34720).
    This exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 30th day of September 1997.

    For the Nuclear Regulatory Commission.
Frank J. Miraglia,
 Acting Director, Office of Nuclear Reactor Regulation.
[FR Doc. 97-26991 Filed 10-9-97; 8:45 am]
BILLING CODE 7590-01-P