[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
