[Federal Register Volume 65, Number 94 (Monday, May 15, 2000)]
[Notices]
[Pages 31021-31022]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-12130]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-346]


FirstEnergy Nuclear Operating Co., Davis-Besse Nuclear Power 
Station, Unit 1; Environmental Assessment and Finding of No Significant 
Impact

    The U.S. Nuclear Regulatory Commission (the Commission) is 
considering the issuance of an exemption, under certain specified 
conditions, from the provisions of (1) 10 CFR part 50, appendix K, 
section I.D.1 which requires that accident evaluations use the 
combination of emergency core cooling system (ECCS) subsystems assumed 
to be operative ``after the most damaging single-failure of ECCS 
equipment has taken place;'' (2) 10 CFR part 50, appendix K, Section 
I.A.4, which specifies that 1.2 times the American Nuclear Standard 
ANS-5 decay heat generation rate for an infinite operating time shall 
be used; and (3) requirements of 10 CFR 50.46(b)(5) and 
50.46(a)(1)(ii), be applied for Facility Operating License No. NPF-3, 
issued to the FirstEnergy Nuclear Operating Company (the licensee), for 
operation of the Davis-Besse Nuclear Power Station, Unit 1, located in 
Ottawa County, Ohio.
    The Commission is taking an action to approve this request prior to 
publication in the Federal Register of its Environmental Assessment and 
Finding of No Significant Impact. In accordance with 10 CFR 51.13, the 
Commission has determined that emergency circumstances are present to 
support the issuance of this exemption prior to publication in the 
Federal Register in that failure to act in a timely way would result in 
prevention of resumption of plant operation.

Environmental Assessment

Identification of the Proposed Action

    The licensee has requested an exemption from 10 CFR 50.46 and 10 
CFR part 50 Appendix K regarding

[[Page 31022]]

proposed modifications to the equipment and procedures for boron 
precipitation control (BPC) during long-term operation following loss 
of coolant accidents (LOCAs). These modifications would be effective 
prior to returning to power following the April 2000 refueling outage. 
The proposed action is in accordance with the licensees' application 
for exemption dated March 15, 2000, as supplemented by submittal dated 
April 3, 2000.

The Need for Proposed Action

    The Code of Federal Regulations at 10 CFR 50.46 provides acceptance 
criteria for the ECCS, including long-term cooling requirements in 
50.46(b)(5) and an option to develop the ECCS evaluation model in 
accordance with appendix K requirements (50.46(a)(1)(ii)). Appendix K 
requires that the ECCS remain operable following the most damaging 
single failure, and it also specifies the decay heat generation rate 
that shall be used.
    In licensee event report (LER) 98-008 (October 1, 1998), Davis-
Besse Nuclear Power Station (DBNPS) reported that for some small-break 
LOCAs, initiation of its active method of BPC could cause steam binding 
in the suction piping of both decay heat removal (DHR) pumps. As part 
of the corrective action for LER 98-008, DBNPS committed to address all 
issues related to long-term LOCA BPC, and to complete a related plant 
modification by the end of the 12th refueling outage that began in 
April, 2000. In response to that commitment, in its March 15, 2000 and 
April 3, 2000 submittals, the licensee described a new active primary 
method for BPC--an improved auxiliary spray path into the pressurizer. 
The licensee also described that a failure anywhere in the flow path 
could result in failure of this method to provide water to the 
pressurizer. Consequently, a backup method was provided that uses flow 
into the decay heat removal suction pipe from a reactor coolant system 
hot leg pipe. The licensee conducted a common mode failure evaluation 
of the two methods and identified several areas where a single failure 
could disable both the primary and backup BPC methods. The licensee 
further, when establishing that boron precipitation will not occur in 
the decay heat removal system cooler, credited flow through hot leg 
nozzle gaps while not establishing that the gaps would always be 
effective, and it did not include all of the specific conservatisms 
required by appendix K. The licensee recognized that its changes did 
not meet all aspects of the single-failure requirement and did not 
include all of the specific required conservatisms. Consequently, it 
requested an exemption since it believed it met the intent of the 
regulations, and it justified its request on the basis of a risk 
evaluation and conservatisms in calculations that result in over-
prediction of the BPC problem. The staff considers that the licensee 
would also need to be exempted from the specific decay heat generation 
rate contained in 10 CFR part 50, appendix K, section I.A.4. Approval 
of this exemption request is needed to permit the licensee to implement 
its plans to ensure BPC.

Environmental Impacts of the Proposed Action

    With regard to potential radiological impacts to the general 
public, the exemption under consideration involves features located 
entirely within the restricted area as defined in 10 CFR part 20. The 
new active methods of BPC are an improvement when compared to the 
existing methods and the entire issue of BPC has been shown to have 
little effect on overall risk. 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 actions.
    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. However, the licensee's exemption request covers 
improvements in response to a licensee commitment to address an 
existing deficiency, improvements that will decrease the risk of BPC 
failure and hence decrease the risk of core damage.
    The licensee addressed further hardware improvements to reduce the 
likelihood of single-failure and established there was little risk 
benefit in doing so, an assessment the staff determined to be 
acceptable. There is no significant benefit in this alternative.

Alternative Use of Resources

    This action does not involve the use of any resources not 
previously considered in the ``Final Environmental Statement Related to 
the Operation of DBNPS Unit 1,'' October 1975.

Agencies and Persons Consulted

    In accordance with its stated policy, on April 18, 2000, the staff 
consulted with the Ohio State official, Carol O'Claire, of the Ohio 
Emergency Management Agency, 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 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 action.
    For further details with respect to the proposed action, see the 
licensee's letters dated March 15 and April 3, 2000, which are 
available for public inspection at the Commission's Public Document 
Room, the Gelman Building, 2120 L Street, NW, Washington, DC. Publicly 
available records are 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 5th day of May 2000.

    For the Nuclear Regulatory Commission.
Singh S. Bajwa,
Director, Project Directorate III, Division of Licensing Project 
Management, Office of Nuclear Reactor Regulation.
[FR Doc. 00-12130 Filed 5-12-00; 8:45 am]
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