[Federal Register Volume 63, Number 73 (Thursday, April 16, 1998)]
[Notices]
[Pages 18943-18944]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-10103]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-286]


In the Matter of Power Authority of the State of New York; 
(Indian Point Nuclear Generating Unit No. 3); Exemption

I

    The Power Authority of the State of New York (the licensee) is the 
holder of Facility Operating License No. DPR-64, which authorizes 
operation of the Indian Point Nuclear Generating Unit No. 3 (IP3). The 
license provides that the licensee is subject to all rules, 
regulations, and orders of the U.S. Nuclear Regulatory Commission (the 
Commission) now or hereafter in effect.
    The facility is a pressurized water reactor located in Westchester 
County, New York.

II

    The Code of Federal Regulations, 10 CFR 50.60, states that the 
reactor coolant pressure boundaries for light water reactors must meet 
the fracture toughness and material surveillance program requirements 
set forth in Appendices G and H to 10 CFR Part 50.
    By letter dated November 3, 1997, the licensee requested an 
exemption from 10 CFR 50.60 to allow the use of the American Society of 
Mechanical Engineers (ASME) Code Case N-514 for the determination of 
the low temperature overpressurization system (LTOP) parameters in 
place of the margins required by Appendix G to 10 CFR Part 50. The Code 
Case limits the overpressurization system (OPS) curve to not greater 
than 110% of the pressure determined to satisfy Appendix G, paragraph 
G-2215 of ASME Code, Section XI, Division 1, further reduced to allow 
for static head due to elevation differences and dynamic head effect of 
the operation of the four reactor coolant pumps. The Code Case also 
allows some latitude in determining the OPS enable temperature.

III

    The NRC has established requirements in 10 CFR Part 50 to protect 
the integrity of the reactor coolant system pressure boundary. As a 
part of these, 10 CFR Part 50, Appendix G, requires that P-T limits be 
established for reactor pressure vessels (RPVs) during normal operation 
and vessel hydrostatic testing and as stated in Appendix G, ``The 
appropriate requirements on * * * the pressure-temperature limits * * * 
must be met for all conditions.'' The Code of Federal

[[Page 18944]]

Regulations, 10 CFR 50.60, states that ``Proposed alternatives to the 
described requirements in Appendices G and H of this part or portions 
thereof may be used when an exemption is granted by the Commission 
under Sec. 50.12.'' Since the licensee wishes to use Code Case N-514 as 
opposed to the requirements of Appendix G, an exemption to the 
regulations is necessary.

IV

    In referring to 10 CFR 50.12 on specific exemptions, the licensee 
cited special circumstance 10 CFR 50.12(a)(2)(ii) on achieving the 
underlying purpose of the regulations, 10 CFR 50.12(a)(iii) on undue 
hardship, and 10 CFR 50.12 (a)(iv) on good faith compliance as their 
bases for requesting this exemption.
    The licensee noted in support of the 10 CFR 50.12(a)(2)(ii) 
criterion that the underlying purpose of the subject regulations is to 
establish limits to protect the reactor vessel from brittle failure 
during low temperature operation and that the OPS provides a physical 
means of protecting these limits. The licensee proposed that 
establishing the OPS pressure setpoint per the N-514 provisions such 
that the vessel pressure would not exceed 110 percent of the P-T limit 
allowables ``* * * * reduces the unnecessary actuation of the LTOP 
system due to normal pressure surges that occur during low temperature 
operation * * * while maintaining acceptable safety margins.'' The 
staff determined that the ``acceptable level of safety'' using N-514 
was based on the conservatism which has been explicitly incorporated 
into the procedure for developing the P-T limits. This procedure, 
referenced from Appendix G to Section XI of the ASME Code, includes the 
following conservatisms: (1) a safety factor of 2 on the pressure 
stresses; (2) a margin factor applied to RTNDT using 
Regulatory Guide 1.99, Revision 2; (3) an assumed \1/4\ T flaw with a 
6:1 aspect ratio; (4) a limiting material toughness based on dynamic 
and crack arrest data.
    The licensee noted in support of the 10 CFR 50.12(a)(iii) criterion 
that, as the reactor vessel ages, the operating window for the LTOP 
system is reduced. This reduced window could lead to inadvertent 
actuation of the LTOP system which could, in turn, lead to rapid 
pressure changes.
    The licensee noted in support of the 10 CFR 50.12(a)(iv) criterion 
that the plant is currently in conformance with 10 CFR 50.60 and that 
relief is being requested in order to maintain sufficient operating 
margin. The licensee also notes that the staff, in Draft Regulatory 
Guide 1050, has proposed to endorse Code Case N-514.
    The staff reviewed the licensee's rationale to support the 
exemption request on the basis of 10 CFR 50.12(a)(iii) and the staff 
concluded that the use of Code Case N-514 would also meet the 
underlying intent of the regulations. Based upon a consideration of the 
conservatism which is explicitly defined in the Appendix G methodology 
(as listed Section 3.0 above), the staff concluded that permitting the 
OPS setpoint to be established such that the vessel pressure would not 
exceed 110 percent of the P-T limits would provide an adequate margin 
of safety against brittle failure of the reactor vessel. This is also 
consistent with the determination that the staff has reached for other 
licensees under similar conditions based on the same considerations.
    The staff reviewed the licensee's rationale to support the 
exemption on the basis of 10 CFR 50.12(a)(iii). The staff has 
previously granted exemptions for other licensees under similar 
circumstances; therefore, the staff has determined that operating with 
a reduced LTOP window would result in an undue hardship that is 
significantly in excess of that incurred by others similarly situated.
    The staff reviewed the licensee's rationale to support the 
exemption on the basis of 10 CFR 50.12(a)(iv) and has determined that 
the licensee has made a good faith effort to comply with the 
regulation.

V

    The NRC staff has determined that there are special circumstances 
present, as specified in 10 CFR 50.12(a)(2)(ii), in that application of 
10 CFR 50.60 is not necessary in order to achieve the underlying 
purpose of this regulation.
    Accordingly, the Commission has determined that, pursuant to 10 CFR 
50.12, this exemption is authorized by law, will not present an undue 
risk to public health and safety, and is consistent with the common 
defense and security.
    Therefore, the Commission hereby grants the following exemption.
    The Power Authority of the State of New York is exempt from the 
requirements of 10 CFR 50.60 in that they are permitted to use Code 
Case N-514 in place of the safety margins required by Appendix G to 10 
CFR Part 50 to determine the LTOP parameters.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will have no significant impact on the 
quality of the human environment (63 FR 17903).
    This exemption is effective upon issuance. Dated at Rockville, 
Maryland, this 10th day of April 1998.

    For the Nuclear Regulatory Commission.
Samuel J. Collins,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 98-10103 Filed 4-15-98; 8:45 am]
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