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Amergen Energy Company, LLC; Three Mile Island Nuclear Station, Unit 1 Environmental Assessment and Finding of No Significant Impact

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

 [Federal Register: May 8, 2001 (Volume 66, Number 89)]
[Notices]               
[Page 23279-23280]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08my01-95]                         

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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-289]
 
Amergen Energy Company, LLC; Three Mile Island Nuclear Station, 
Unit 1 Environmental Assessment and Finding of No Significant Impact

    The U.S. Nuclear Regulatory Commission (NRC) is considering 
issuance of an exemption from certain provisions of Sections 50.44 and 
50.46 and Appendix K of Title 10 of the Code of Federal Regulations (10 
CFR) Part 50 for Facility Operating License No. DPR-50, issued to 
AmerGen Energy Company, LLC (the licensee), for operation of the Three 
Mile Island Nuclear Station, Unit 1 (TMI-1), located in Dauphin County, 
Pennsylvania.

Environmental Assessment

Identification of the Proposed Action

    The licensee requests an exemption from the provisions of: (1) 10 
CFR 50.44, ``Standards for combustible gas control system in light-
water-cooled power reactors,'' which provide requirements to control 
hydrogen generated by Zircaloy or ZIRLO fuel cladding after a 
postulated loss-of-coolant accident (LOCA); (2) 10 CFR 50.46, 
``Acceptance criteria for emergency core cooling systems for light-
water nuclear power reactors,'' which requires the calculated emergency 
core cooling system (ECCS) performance for reactors with Zircaloy or 
ZIRLO fuel cladding to meet certain criteria; and (3) Appendix K, 
``ECCS Evaluation Models,'' which presumes the use of Zircaloy or ZIRLO 
fuel cladding when doing calculations for energy release, cladding 
oxidation, and hydrogen generation after a postulated LOCA.
    The proposed action would allow the licensee to generally use the 
M5 advanced alloy for fuel rod cladding in fuel assemblies at TMI-1. 
Limited use of M5 alloy in demonstration assemblies at TMI-1 had 
previously been approved. M5 alloy would also be used in fuel assembly 
spacer grids and fuel rod end plugs and fuel assembly guide and 
instrument tubes. M5 alloy material would be used in lieu of Zircaloy 
or ZIRLO, the materials assumed to be used in the cited regulations. 
The fuel assemblies would be loaded into the TMI-1 reactor core during 
the refueling outage in the fall of 2001, and in use during Cycle 14 
and beyond operation.
    The proposed action is in accordance with the licensee's 
application for exemption dated December 20, 2000, as supplemented by 
letter dated March 14, 2001.

The Need for the Proposed Action

    Appendix K of 10 CFR part 50 and 10 CFR 50.46(a)(1)(i) require the 
demonstration of adequate ECCS performance for light-water reactors 
that contain fuel consisting of uranium oxide pellets enclosed in 
Zircaloy or ZIRLO tubes. In addition, 10 CFR 50.44(a) addresses 
requirements to control hydrogen generated by Zircaloy or ZIRLO fuel 
after a postulated LOCA. Each of these three regulations, either 
implicitly or explicitly assume that either Zircaloy or ZIRLO is used 
as the fuel rod cladding material. In order to accommodate the high 
fuel rod burnups that are required for modern fuel management and core 
designs, Framatome Cogema Fuels (FCF), developed the M5 advanced fuel 
rod cladding and fuel assembly structural material. M5 is an alloy 
comprised primarily of zirconium (~99 percent) and niobium (~ 1 
percent) that has demonstrated superior corrosion resistance and 
reduced irradiation induced growth relative to both standard and low-
tin Zircaloy. However, since the chemical composition of the M5 
advanced alloy differs from the specifications of either Zircaloy or 
ZIRLO, use of the M5 advanced alloy falls outside of the strict 
interpretation of these regulations. Therefore, approval of this 
exemption request is needed to permit the use of the M5 advanced alloy 
as a fuel rod cladding material at TMI-1. Limited use of the M5 alloy 
in demonstration assemblies at TMI-1 had previously been approved.
    Pursuant to 10 CFR 50.12, the NRC may grant exemptions which are 
authorized by law, will not present an undue risk to the health and 
safety of the public, and are consistent with the common defense and 
security, provided that special circumstances are present. Pursuant to 
10 CFR 50.12(a)(2)(ii), the Commission believes that special 
circumstances are present whenever application of the regulation in the 
particular circumstances is not necessary to achieve the underlying 
purpose of the rule. The underlying purpose of 10 CFR 50.46 is to 
ensure that facilities have adequate acceptance criteria for ECCS. FCF 
demonstrates in its topical report BAW-10227P-A, ``Evaluation of 
Advanced Cladding and

[[Page 23280]]

Structural Material (M5) in PWR [pressurized-water reactor] Reactor 
Fuel,'' submitted to the NRC for review and approval on September 30, 
1997, and approved by the NRC in a letter dated February 4, 2000, that 
the effectiveness of the ECCS will not be affected by a change from 
Zircaloy fuel rod cladding to M5 fuel rod cladding. The analysis 
described in BAW-10227P-A also demonstrates that the ECCS acceptance 
criteria applied to reactors fueled with Zircaloy clad fuel are also 
applicable to reactors fueled with M5 fuel rod cladding. Therefore, 
since the underlying purpose of 10 CFR 50.46 is achieved through the 
use of the M5 advanced alloy as a fuel rod cladding material, the 
special circumstances required by 10 CFR 50.12(a)(2)(ii) for granting 
an exemption from 10 CFR 50.46 exist. The underlying purposes of 10 CFR 
50.44 and appendix K of 10 CFR 50 are to ensure that cladding oxidation 
and hydrogen generation are appropriately limited during a postulated 
LOCA and conservatively accounted for in the ECCS evaluation model. The 
NRC staff has evaluated the impact of using M5 advanced alloy as fuel 
cladding material and determined that the impact is within that 
considered in the design basis for TMI-1. Therefore, the underlying 
purposes of 10 CFR 50.44 and appendix K of 10 CFR Part 50 are met. 
Since the underlying purposes of 10 CFR 50.44, 50.46, and appendix K of 
10 CFR Part 50 are achieved with the use of M5 advanced alloy as fuel 
rod cladding material, the special circumstances required by 10 CFR 
50.12(a)(2)(ii) for granting the exemption are met.

Environmental Impacts of the Proposed Action

    The NRC has completed its evaluation of the proposed action and 
concludes that the use of M5 advanced alloy as fuel rod cladding will 
not have a detrimental effect during a postulated LOCA. The NRC staff 
has further determined that since the geometry differences between the 
M5 alloy and Zircaloy are slight and would have virtually no thermal-
hydraulic effect while fuel rods utilizing the two alloys as cladding 
material are co-resident in the same core, there is no need for a 
mixed-core penalty in LOCA ECCS model evaluations to compensate for 
material differences.
    The proposed action will not significantly increase the probability 
or consequences of accidents, no changes are being made in the types of 
any effluents that may be released off site, and there is no 
significant increase in occupational or public radiation exposure. 
Therefore, there are no significant radiological environmental impacts 
associated with the proposed action.
    With regard to potential nonradiological impacts, the proposed 
action does not involve any historic sites. It does not affect 
nonradiological plant effluents and has no other environmental impact. 
Therefore, there are no significant nonradiological environmental 
impacts associated with the proposed action.
    Accordingly, the NRC concludes that there are no significant 
environmental impacts associated with the proposed action.

Alternatives to the Proposed Action

    As an alternative to the proposed action, the staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). 
Denial of the application would result in no change in current 
environmental impacts. The environmental impacts of the proposed action 
and the alternative action are similar.

Alternative Use of Resources

    This action does not involve the use of any resources not 
previously considered in the Final Environmental Statement for the 
Three Mile Island Nuclear Station, Unit 1, dated December 1972.

Agencies and Persons Consulted

    In accordance with its stated policy, on April 4, 2001, the staff 
consulted with the Pennsylvania State official, Mr. Michael Murphy of 
the Bureau of Radiation Protection, regarding the environmental impact 
of the proposed action. The State official had no comments.

Finding of No Significant Impact

    On the basis of the environmental assessment, the NRC concludes 
that the proposed action will not have a significant effect on the 
quality of the human environment. Accordingly, the NRC has determined 
not to prepare an environmental impact statement for the proposed 
action.
    For further details with respect to the proposed action, see the 
licensee's letter dated December 20, 2000, as supplemented by letter 
dated March 14, 2001. Documents may be examined, and/or copied for a 
fee, at the NRC's Public Document Room, located at One White Flint 
North, 11555 Rockville Pike (first floor), Rockville, Maryland. 
Publicly available records will be accessible electronically from the 
ADAMS Public Library component on the NRC Web site, http:\\www.nrc.gov 
(the Electronic Reading Room).

    Dated at Rockville, Maryland, this 2nd day of May 2001.

    For the Nuclear Regulatory Commission.
Timothy G. Colburn,
Senior Project Manager, Section 1, Project Directorate I, Division of 
Licensing Project Management, Office of Nuclear Reactor Regulation.
[FR Doc. 01-11568 Filed 5-7-01; 8:45 am]
BILLING CODE 7590-01-P

 
 

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