[Federal Register Volume 61, Number 15 (Tuesday, January 23, 1996)]
[Notices]
[Pages 1787-1788]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-810]



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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-155]


Consumers Power Company (Big Rock Point Plant); Exemption

I

    Consumers Power Company (CPCo, the licensee) is the holder of 
Facility Operating License No. DPR-6 which authorizes operation of the 
Big Rock Point Plant (the facility). The facility consists of a boiling 
water reactor located at the licensee's site in Charlevoix County, 
Michigan. The license provides, among other things, that the facility 
is subject to all rules, regulations, and orders of the Nuclear 
Regulatory Commission (the Commission) now or hereafter in effect.

II

    Pursuant to 10 CFR 50.12(a), the NRC may grant exemptions from the 
requirements of the regulations (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 III.D.1.(a) of Appendix J [Option A] to 10 CFR Part 50 
requires the performance of three Type A containment integrated leak 
rate tests (ILRTs) at approximately equal intervals during each of the 
10-year service periods of the primary containment.

III

    By letter dated November 8, 1995, the licensee requested a one-time 
schedular exemption from the ``approximately equal time intervals'' 
requirement of 10 CFR Part 50, Appendix J, Section III.D.1.(a). 
Specifically, the proposed exemption would allow CPCo to delay the Type 
A test until the January 1997 refueling outage. The interval between 
the Type A tests would increase from 47 months to 59 months.
    The licensee's request cites the special circumstances of 10 CFR 
50.12, paragraph (a)(2)(ii), as the basis for the exemption. In 10 CFR 
Part 50 Appendix J, it states that the purpose of the Type A, B, and C 
tests is to assure that leakage through the primary containment shall 
not exceed the allowable leakage rate values as specified in the 
technical specifications or associated bases. CPCo stated that the 
existing Type B and Type C tests, which are unaffected by this proposed 
change, will continue to detect leakage through containment valves, 
penetrations, and airlocks.
    The licensee has analyzed the results of previous Type A tests 
performed at the Big Rock Point Plant to show adequate containment 
performance. The licensee will continue to conduct Type B and Type C 
local leak rate tests which historically have been shown to be the 
principal means of detecting containment leakage paths with the Type A 
tests confirming the Type B and C tests results. It is also noted that 
the licensee would perform a general inspection of accessible interior 
or exterior surfaces of the containment structures and components 
although it is only required by Appendix J to be conducted in 
conjunction with Type A tests.
    The testing history and structural capability of the containment 
establish that there is significant assurance that the extended 
interval between Type A tests will not adversely impact the leak-tight 
integrity of the containment and that performance of the Type A test is 
not necessary to meet the underlying purpose of Appendix J.
    The alternative actions proposed by the licensee in the exemption 
request provide reasonable assurance that leakage will not exceed 
acceptable levels. Therefore, granting this exemption does not present 
an undue risk to public health and safety.
    The underlying purpose of the requirement to perform Type A 
containment test leak rate tests at intervals during the 10-year 
service period is to ensure that any potential 

[[Page 1788]]
leakage pathways through the containment boundary are identified within 
a time span that prevents significant degradation from continuing.
    The licensee notes that the results of the Type A testing have been 
confirmatory of the Type B and Type C tests which will continue to be 
performed. The licensee has stated that it will perform the general 
inspection of accessible interior or exterior surfaces of the 
containment structures and components although it is only required by 
Appendix J to be conducted in conjunction with Type A tests. The NRC 
staff considers that these inspections, though limited in scope, 
provide an important added level of confidence in the continued 
integrity of the containment boundary.
    The NRC staff has also made use of the information in a draft staff 
report, NUREG-1493, ``Performance-based Containment Leak-Test 
Program,'' which provides the technical justification for Option B of 
Appendix J which includes a 10-year test interval for Type A tests. The 
Type A test measures overall containment leakage. However, operating 
experience with all types of containments used in this country 
demonstrates that essentially all containment leakage can be detected 
by local leak rate tests (Type B and Type C). According to results 
given in NUREG-1493, out of 180 ILRT reports covering 110 individual 
reactors and approximately 770 years of operating history, only 5 ILRT 
failures were found which local leakage rate testing could not detect. 
This is 3 percent of all failures. This study agrees well with previous 
NRC staff studies which show that Type B and Type C testing can detect 
a very large percentage of containment leaks. The Big Rock Point Plant 
experience has also been consistent with these results.
    The Nuclear Management and Resources Council (NUMARC), now the 
Nuclear Energy Institute (NEI), collected and provided the NRC staff 
with summaries of data to assist in the preparation of Option B to 
Appendix J. NUMARC collected results of 144 ILRTs from 33 units; 23 
ILRTs exceeded 1 La. Of these, only nine were not Type B or Type C 
leakage penalties. The NEI data also added another perspective. The NEI 
data show that in about one-third of the cases exceeding allowable 
leakage, the as-found leakage was less than 2 La; in one case the 
leakage was found to be approximately 2 La; in one case the 
leakage was less than 3 La; one case approached 10 La; and in 
one case the as-found leakage was found to be approximately 21 La. 
For about half of the failed ILRTs the as-found leakage was not 
quantified. These data show that, for those ILRTs for which the leakage 
was quantified, the leakage values are small in comparison to the 
leakage value at which the risk to the public starts to increase over 
the value of risk corresponding to La (approximate 200 La, as 
discussed in NUREG-1493). Therefore, based on these considerations, it 
is unlikely that an extension of one cycle for the performance of the 
Appendix J, Type A test at the Big Rock Point Plant would result in 
significant degradation of the overall containment integrity. As a 
result, the application of the regulation in these particular 
circumstances is not necessary to achieve the underlying purpose of the 
rule. Therefore, special circumstances exist pursuant to 10 CFR 
50.12(a)(2)(ii).
    Thus, the staff concludes that an exemption from the requirements 
of paragraph III.D.1(a) of Appendix J to 10 CFR Part 50 should be 
granted. The Commission further determines that special circumstances 
as provided in 10 CFR 50.12(a)(2)(ii) are present justifying the 
exemption; namely, that application of the regulation in the particular 
circumstances is not necessary to achieve the underlying purpose of the 
rule.

IV

    Accordingly, the Commission has determined, pursuant to 10 CFR 
50.12, that this exemption is authorized by law, and 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 
in that application of the regulation in these particular circumstances 
is not necessary to achieve the underlying purpose of the rule.
    Therefore, the Commission hereby grants the exemption from 10 CFR 
Part 50, Appendix J, Section III.D.1.(a) to the extent that the 
Appendix J test interval for performing Type A tests may be extended 
one cycle until the January 1997 refueling outage, on a one-time basis 
only, for the Big Rock Point Plant, provided that the general 
containment inspection is performed and as described in Section III 
above.
    Pursuant to 10 CFR 51.32, the Commission has determined that 
granting this exemption will not have a significant effect on the 
quality of the human environment (61 FR 422).
    This exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 16th day of January 1996.

    For the Nuclear Regulatory Commission.
Jack W. Roe,
Director, Division of Reactor Projects--III/IV, Office of Nuclear 
Reactor Regulation.
[FR Doc. 96-810 Filed 1-22-96; 8:45 am]
BILLING CODE 7590-01-P