[Federal Register Volume 59, Number 217 (Thursday, November 10, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-27860]


[[Page Unknown]]

[Federal Register: November 10, 1994]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-237]

 

Commonwealth Edison Co.; Environmental Assessment and Finding of 
No Significant Impact

    The U.S. Nuclear Regulatory Commission (the Commission) is 
considering issuance of a schedular exemption from the requirement of 
10 CFR Part 50, Appendix J, to Facility Operating License No. DPR-19, 
issued to Commonwealth Edison Company, (ComEd the licensee), for 
operation of the Dresden Nuclear Power Station, Unit 2, located in 
Grundy County, Illinois.

Environmental Assessment

Identification of Proposed Action

    The proposed action would grant a schedular exemption from the 
requirements of Section III.A.6.(b) (Type A test) of Appendix J to 10 
CFR Part 50 relating to the primary reactor containment leakage testing 
for water cooled reactors. The purpose of the test is to assure that 
leakage through the primary reactor containment shall not exceed 
allowable leakage rate values as specified in the Technical 
Specifications (TS) and that periodic surveillance is performed.
    The proposed action is in accordance with the licensee's request 
for an exemption dated October 28, 1994.

Need for the Proposed Action

    The licensee requested, pursuant to 10 CFR 50.12(a), a one-time 
schedular exemption for Dresden, Unit 2, from the integrated leak rate 
test (ILRT) intervals for the Type A leak rate test required by 10 CFR 
Part 50, Appendix J. Section III.A.6.(b). The exemption is requested to 
avoid the potential for a reactor shutdown. If a forced outage is 
imposed to perform testing, it would present undue hardship and cost in 
the form of increased radiological exposure. Furthermore, if a forced 
outage is imposed to perform the required testing, an additional plant 
shutdown and startup will be required. ComEd has had to reschedule the 
Dresden, Unit 2, refueling outage from September 1994 to July 1995, 
because of two forced maintenance outages. Increasing the interval 
between refueling outages will cause Dresden, Unit 2, to exceed the 
Type A leak rate testing surveillance interval required for the Type A 
leak rate test which can not be performed during reactor operation.

Environmental Impacts of the Proposed Action

    The proposed action includes an exemption from performing the Type 
A test for a maximum period of 242 days beyond the required Appendix J 
test interval. As stated in 10 CFR Part 50, Appendix J, the purpose of 
the primary containment leak rate testing requirements is to ensure 
that leakage rates are maintained within the TS requirements and to 
assure that proper maintenance and repairs are performed throughout the 
service life of the containment boundary components. The requested 
exemption is consistent with the intent of 10 CFR 50.12(a), in that it 
represents a one-time only schedular extension of short duration. The 
required leak tests will still be performed to assess compliance with 
TS requirements, albeit later, and to assure that any required 
maintenance or repair is performed. As noted in Section III.A.6.(b) of 
Appendix J, it was intended that the testing be performed during 
refueling outages or other convenient intervals. Extending the Appendix 
J interval by a small amount to reach the next refueling outage will 
not significantly impact the integrity of the containment boundary and, 
therefore, will not significantly impact the consequences of an 
accident or transient in the unlikely event of occurrence during the 
242 day extended period. In order to provide an added margin of safety 
and to account for possible increases in the leakage rates of untested 
volumes during the relatively short period of the exemption, Dresden 
Unit 2 will impose an administrative limit for minimum pathway leakage 
of 85 percent of 0.75La for the remaining Unit 2 fuel cycle. Past Unit 
2 local leak rate test data have, in general, demonstrated good leak 
rate test results. The two consecutive Type A ILRT failures that have 
placed Unit 2 on the accelerated test schedule were the result of the 
addition of Type B and C test results to the Type A leakage and not 
problems with the Type A test boundaries. The containment leakage rate 
minus the Type B and C leakages for the last two Type A test failures 
during D2R12 and D2R13 were 285.50 standard cubic feet per hour (scfh) 
and 302.62 scfh, respectively. These values are 47 percent and 50 
percent of the Type A ILRT acceptance criteria of 610.56 scfh (.75La). 
The above data, along with the station imposed limit for minimum 
pathway leakage, provide a basis for showing that the probability of 
exceeding the off site dose rates established in 10 CFR Part 100, will 
not be increased by extending the current Type A testing interval for a 
maximum of 242 days. The proposed exemption does not affect plant 
nonradiological effluents and has no other environmental impact. 
Therefore, the Commission concludes there are no measurable 
environmental impacts associated with the proposed exemption.

Alternatives to the Proposed Action

    Since the Commission has concluded there is no measurable 
environmental impact associated with the proposed exemption, any 
alternatives with equal or greater environmental impact need not be 
evaluated. The principal alternative to the exemption would be to 
require rigid compliance with the requirements of Section III.A.6.(b) 
of Appendix J to 10 CFR Part 50. Such action would not enhance the 
protection of the environment and would result in unjustified costs for 
the licensee.

Alternate Use of Resources

    This action does not involve the use of any resources not 
considered previously in the Final Environmental Statements for 
Dresden, Units 2 and 3, dated November 1973.

Agencies and Persons Consulted

    The staff consulted with the Illinois State official regarding the 
environmental impact of the proposed action. The State official had no 
comments.

Finding of No Significant Impact

    Based upon the foregoing environmental assessment, the Commission 
concludes that the proposed action will not have a significant effect 
on the quality of the human environment. Accordingly, the Commission 
has determined not to prepare an environmental impact statement for the 
proposed exemption.
    For further details with respect to this action, see the licensee's 
request for exemption dated October 28, 1994, which is available for 
public inspection at the Commission's Public Document Room, The Gelman 
Building, 2120 L Street, NW., Washington, D.C., and at the local public 
document room located at the Morris Public Library, 604 Liberty Street, 
Morris, Illinois 60451.

    Dated at Rockville, Maryland, this 4th day of November, 1994.

    For the Nuclear Regulatory Commission.
Robert A. Capra,
Director, Project Directorate III/2, Division of Reactor Projects--III/
IV, Office of Nuclear Reactor Regulation.
[FR Doc. 94-27860 Filed 11-9-94; 8:45 am]
BILLING CODE 7590-01-M