[Federal Register Volume 59, Number 12 (Wednesday, January 19, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-1219]


[[Page Unknown]]

[Federal Register: January 19, 1994]


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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-325 and 50-324]

 

Carolina Power & Light Co., Brunswick Steam Electric Plant, Units 
1 and 2

Exemption

I

    The Carolina Power & Light Company (the licensee) is the holder of 
Facility Operating License Nos. DPR-71 and DPR-62 which authorize 
operation of the Brunswick Steam Electric Plant, Units 1 and 2 (BSEP or 
the facility), respectively, at steady state power levels not in excess 
of 2436 megawatts thermal. The facility consists of two boiling water 
reactors located at the licensee's site in Brunswick County, North 
Carolina. The Facility Operating License provides, among other things, 
that BSEP is subject to all rules, regulations and Orders of the 
Nuclear Regulatory Commission (the Commission) now and hereafter in 
effect.

II

    Section III.A.5.(b)(2) of Appendix J establishes an acceptance 
criterion for the total measured containment leakage rate, Lam, 
measured at the peak containment internal pressure, Pa, calculated 
for the design basis accident. Since the periodic Type A tests at BSEP 
are conducted at Pa, the acceptance criterion for these tests is 
that Lam be less than 75 percent of the maximum allowable leakage 
rate, La, as specified in Technical Specification 4.6.1.2.b; this 
value is 0.5 percent by weight of the containment air per 24 hours. 
Section III.A.6(b) of Appendix J requires that, if two consecutive 
periodic Type A tests fail to meet the criteria in section 
III.A.5.(b)(2), notwithstanding the periodic retest schedule of section 
III.D, a Type A test must be performed at each plant shutdown for 
refueling, or approximately every 18 months, whichever occurs first, 
until two consecutive Type A tests meet the criteria in section 
III.A.5.(b).
    The exemption would allow both BSEP units to return to a normal 
testing frequency so the next Unit 1 Type A test would then be 
performed during the Reload 9 outage scheduled for March 1995 and the 
next Unit 2 test during the Reload 12 outage scheduled for March 1997.
    In its letter dated October 19, 1993, requesting a one-time 
exemption from the schedular requirements of Section III.A.6.(b) of 
Appendix J, the licensee stated that each unit is currently in an 
accelerated testing condition due to as-found testing failures which, 
except for the 1987 Unit 1 test, were within La leakage limits but 
exceeded the current 0.75 La leakage limit of Section 
III.A.5.(b)(2) of Appendix J to 10 CFR Part 50. The licensee has based 
its request on the fact that the as-left limit of 0.75 La was 
specified in Appendix J to provide a margin for possible deterioration 
of the containment leak-tightness during the interval between Type A 
tests. The licensee states that this margin for deterioration is no 
longer needed when the as-found Type A test is performed. The licensee 
believes that it should be technically acceptable to use La as the 
as-found Type A test acceptance criterion. The license provides further 
justification in that the Type A test are normally terminated as soon 
as the acceptance criteria are satisfied for economic reasons. The 
licensee believes that this process may result in leak rates that may 
not be indicative of actual primary containment leakage and that, if 
the test durations were extended, the quantified leakage would be less 
than that reported to the NRC.
    The as-found Type A condition is represented by the leakage rate 
calculated by adding the differences between the as-found and as-left 
measured local leakage rates from each Type B and Type C test to the 
leakage rate measured in the Type A test. These Type B and Type C tests 
are usually conducted prior to conducting the Type A test. In the event 
that potentially excessive leakage paths are identified that would 
interfere with the satisfactory completion of a period Type A test and 
such paths are isolated during the test, the Type B or Type C as-found 
leakage rates measured on the isolated penetrations after the 
completion of the Type A test are added into the Type A as-found 
leakage rate total. The as-left Type A condition is represented by the 
periodic Type A leakage rate after any required repairs and/or 
adjustments are made.
    The staff reviewed the history of the Type A tests conducted at 
BSEP and found that the last two Type A as-found test results have been 
failures as noted below:

------------------------------------------------------------------------
                                                            As-         
                                                           left    0.75 
 Date                                                      leak     La  
  of           As-found leak rate (% wt. per day)          rate    limit
 test                                                     (% wt.  (% wt.
                                                            per     per 
                                                           day)    day) 
------------------------------------------------------------------------
                       Unit 1 Type A Test History                       
                                                                        
------------------------------------------------------------------------
1987..  Greater than La.................................   .2150   0.375
1991..  .4956...........................................   .3408    .375
                                                                        
------------------------------------------------------------------------
                       Unit 2 Type A Test History                       
                                                                        
------------------------------------------------------------------------
                                                                        
1991..  .4042...........................................   .3552    .375
1991..  .4420...........................................   .3511    .375
------------------------------------------------------------------------


    The staff noted that the last two test results for each unit has 
exceeded the acceptance criterion of 0.75 La required by Appendix 
J. Except for the 1987 test on Unit 1, the test results did not exceed 
the maximum allowable rate of 1.0 La. The licensee indicated the 
1987 Unit 1 failure was caused by a containment penetration failure 
identified during the local leak rate testing. The licensee also stated 
the primary reason for failing the as-found limits is considered to be 
the leakage savings additions from Type C testing of valves and the 
Type B testing of penetrations, where leakage rates of repaired or 
replaced components are added into the integrated Type A test results.
    The licensee stated the major contributors to the 1987 Unit 1 test 
failure were from (1) penetration X9A, Feedwater Loop A Injection, and 
(2) penetration X54E, Containment Monitor, CAC-AT-1262, Discharge. The 
licensee further stated the corrective actions to repair several valves 
associated with these penetrations were completed, and if the leakage 
from these penetrations was not considered, the as-found leakage 
savings would have been 0.049% wt. per day. For the 1991 Unit 1 Type A 
test, the majors contributors were stated to be (1) penetration X9B, 
Feedwater Loop B Injection, (2) penetration X14, Reactor Water Cleanup 
(RWCU) Suction Line, and (3) penetration X10, Reactor Core Isolation 
Cooling Turbine Steam Supply Line. These penetrations were repaired by 
the replacement or repair of affected valves.
    The licensee stated that the major contributors to the 1991 Unit 2 
test failure were from (1) penetration X220, Torus Purge to Standby 
Gas, and (2) penetration X8, Main Steam Line Drain. The major 
contributors to the 1992 Unit 2 failure were from (1) penetration X14, 
RWCU Suction, and (2) penetration X12, Residual Heat Removal Shutdown 
Cooling Suction. The licensee conducted repairs to several valves to 
correct the leakage through each of these penetrations.
    The NRC staff has reviewed the licensee's request and basis and 
finds that there is adequate assurance that there will not be any 
significant undetected degradation in the primary containment leakage 
during the next Type A test interval in that the primary contributors 
to potentially excessive leakage paths will be measured during the 
required Type B and Type C tests. These latter tests will be conducted 
at least once during each 18-month refueling outage, but in no case at 
intervals greater than 2 years (Sections III.D.2 and III.D.3 of 
Appendix J to 10 CFR Part 50).
    The staff agrees that the subject exemption request does not pose 
any undue risk to the public health and safety in that (1) the last as-
left Type A test leakage rates were below 0.75 La and (2) the 
licensee will continue to demonstrate that the test results from the 
Type B and C local leak rate tests will be no greater than their 
specified values in the Brunswick Technical Specifications prior to 
restart after a refueling outage. Any potentially excessive leakage 
paths will continue to be repaired and/or adjusted prior to restart and 
at intervals of 18 months, thereby continuing to ensure the integrity 
of the containment. Based on these considerations, the staff concludes 
that the licensee's request for a one-time exemption to Section 
III.A.6(b) of Appendix J to 10 CFR part 50 will ensure compliance with 
the maximum permissible containment leakage rate specified in the 
Brunswick Technical Specifications and, thus, should be granted.

III

    Accordingly, the Commission has determined that, pursuant to 10 CFR 
50.12, 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; namely, that the application of this 
regulation is not necessary to achieve the underlying purpose of the 
rule. The underlying purpose of the rule is to provide a margin for 
possible deterioration of the containment leak-tightness during the 
interval between Type A tests. The Licensee has provided adequate 
assurance, as set forth above, that the underlying purpose of the rule 
will be achieved in that the primary contributors to potentially 
excessive leakage paths will be measured during Type B and C testing. 
Further, the staff also finds that the protection provided by the 
licensee against potentially excessive containment leakage will not 
present an undue risk to the public health and safety. The application 
of the regulation is not necessary to assure the integrity of the 
containment in the event of a postulated design basis loss-of-coolant 
accident.
    The Commission hereby grants the one-time exemption with respect to 
the requirements of 10 CFR part 50, Appendix J, Section III.A.5.(b)(2), 
to return both BSEP units to a normal Type A test frequency. Should two 
consecutive periodic Type A tests fail to meet the criteria in section 
III.A.5.(b)(2) in the future, notwithstanding the periodic retest 
schedule of section III.D, the licensee will be required to take the 
appropriate actions as specified in Section III.A.6(b) of Appendix J to 
10 CFR 50.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of the subject exemption will not have a significant effect on 
the quality of the human environment (59 FR 1569).
    The Exemption is effective upon issuance.

    Dated at Rockville, Maryland, this 11th day of January 1994.

    For the Nuclear Regulatory Commission.
Steven A. Varga,
Director, Division of Reactor Projects--I/II, Office of Nuclear Reactor 
Regulation.
[FR Doc. 94-1219 Filed 1-18-94; 8:45 am]
BILLING CODE 7590-01-M