[Federal Register Volume 59, Number 247 (Tuesday, December 27, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-31775]


[[Page Unknown]]

[Federal Register: December 27, 1994]


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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-213]

 

Connecticut Yankee Atomic Power Company; Haddam Neck Plant; 
Environmental Assessment and Finding of No Significant Impact

    The U.S. Nuclear Regulatory Commission (the Commission) is 
considering issuance of an amendment to Facility Operating License No. 
DPR-61, issued to Connecticut Yankee Atomic Power Company (CYAPCO, the 
licensee), for operation of the Haddam Neck Plant, located in Middlesex 
County, Connecticut.

Environmental Assessment

Identification of the Proposed Action

    The proposed amendment would revise Technical Specifications (TS) 
3.4.1.1, ``Reactor Coolant Loops and Coolant Circular,'' TS 3.7.1.1., 
``Safety Valves--Self Actuation Function,'' Table 3.7-1, ``Steam Line 
Safety Valves Per Loop,'' and their associated Bases sections. In 
addition, the TS change will add a new TS 3.7.1.1.2, ``Safety Valves--
Remote Actuation Function,'' with an associated Bases change. The 
proposed action is in accordance with the licensee's amendment request 
dated May 4, 1993, as supplemented August 9 and 18, 1993, January 25, 
April 11, and June 22, 1994.

The Need for the Proposed Action

    By letter dated May 4, 1993, CYAPCO informed the staff that during 
the Cycle 17 refueling outage, four main steam safety valves (MSSVs) 
(one per steam line) were replaced with valves that would provide 
remote manual operation. These valves have dual capability, as MSSVs 
(self-actuating function) and as atmospheric dump valves (ADV) (remote-
actuation function). These valves will significantly increase the 
remote manual atmospheric steam dump capability of the Haddam Neck 
Plant. To assure the remote manual operation of the new MSSVs, the 
licensee has proposed adding the remote function of the MSSVs to the 
TS. The licensee is also removing the loop isolation valves from the 
TS. In addition, the appropriate Bases sections will be modified to 
include a discussion of the remote actuation capability of the MSSVs 
and remove the discussion regarding the use of the loop isolation 
valves for mitigation of a steam generator tube rupture (SGTR) event.

Environmental Impacts of the Proposed Action

    The TS changes, hardware modifications, and the associated analysis 
will change the licensing basis for mitigating a SGTR event at the 
Haddam Neck Plant. The new MSSVs can be operated remotely from the main 
control room, as well as locally (self-actuating) for steam generator 
overpressure protection. This modification provides the plant the 
ability to rapidly cool down and depressurize without reliance on the 
main condensor or other nonsafety-related balance of plant equipment. 
The plant will now mitigate a SGTR event with the use of the MSSVs as 
remote ADV rather than the loop isolation valves. The use of ADVs to 
limit break flow for a SGTR event is consistent with most other 
Westinghouse PWR plants. The Commission has completed its evaluation of 
the proposed TS changes and concludes that the new MSSVs still meet the 
original design (self-actuating function) and can also be used as 
atmospheric steam dump valves (remote-actuation function). The proposed 
TS changes will provide assurance of the operability of both functions. 
The removal of the loop isolation valves are acceptable because the 
licensee has demonstrated that SGTR events will now be mitigated with 
the use of the MSSVs as ADVs rather than the loop isolation valves. The 
Updated Final Safety Analysis Report will be revised to reflect the 
change in the licensing basis associated with the mitigation of a SGTR 
event.
    The proposed TS change will not increase the probability or 
consequences of accidents, no changes are being made in the types of 
any effluents that may be released offsite, and there is no significant 
increase in the allowable individual or cumulative occupational 
radiation exposure. Accordingly, the Commission concludes that there 
are no significant radiological environmental impacts associated with 
the proposed TS amendment.
    With regard to potential nonradiological impacts, the proposed 
amendment involves features located entirely within the restricted area 
as defined in 10 CFR part 20. It does not affect nonradiological plant 
effluents and has no other environmental impact. Accordingly, the 
Commission concludes that there are no significant nonradiological 
environmental impacts associated with the proposed amendment.

Alternatives to the Proposed Action

    Since the Commission has concluded there is no measurable 
environmental impact associated with the proposed amendment, any 
alternatives with equal or greater environmental impact need not be 
evaluated. The principal alternative to the amendment would be to deny 
the amendment request. Such action would not enhance the protection of 
the environment.

Alternative Use of Resources

    This action does not involve the use of resources not considered 
previously in the Final Environmental Statement for the Haddam Neck 
Plant.

Agencies and Persons Consulted

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

Finding of No Significant Impact

    Based upon 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 amendment.
    For further details with respect to the proposed action, see the 
licensee's letter dated May 4, 1993, as supplemented August 9, and 18, 
1993, January 25, April 11, and June 22, 1994, which are available for 
public inspection at the Commission's Public Document Room, the Gelman 
Building, 2120 L Street, NW., Washington, DC, and at the local public 
document room located at the Russell Library, 123 Broad Street, 
Middletown, CT 06547.

    Dated at Rockville, Maryland, this 16th day of December 1994.

    For the Nuclear Regulatory Commission.
Phillip F. McKee,
Director, Project Directorate I-4, Division of Reactor Projects--I/II, 
Office of Nuclear Reactor Regulation.
[FR Doc. 94-31775 Filed 12-23-94; 9:45 am]
BILLING CODE 7590-01-M