2010-4846. Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events; Correcting Amendment

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Final rule; correcting amendment.

SUMMARY:

The Nuclear Regulatory Commission (NRC) is revising its regulations to add a table that was inadvertently omitted in a correction document published on February 3, 2010 (75 FR 5495). The February 3, 2010 document corrected a final rule published on January 4, 2010 (75 FR 13), that amends the NRC's regulations to provide alternate fracture toughness requirements for protection against pressurized thermal shock (PTS) events for pressurized water reactor (PWR) pressure vessels.

DATES:

The correction is effective March 8, 2010, and is applicable to February 3, 2010, the date the original rule became effective.

FOR FURTHER INFORMATION CONTACT:

Michael T. Lesar, Chief, Rulemaking and Directives Branch, Office of Administration, Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone [phone], e-mail [e-mail].

SUPPLEMENTARY INFORMATION:

This document adds Table 7 to the NRC's regulations at 10 CFR 50.61a(g) which was inadvertently omitted in a document published on February 3, 2010 (75 FR 5495). Therefore, the NRC finds that notice and opportunity for public comment on this corrective action is unnecessary.

List of Subjects in 10 CFR Part 50

• Antitrust
• Classified information
• Criminal penalties
• Fire protection
• Intergovernmental relations
• Nuclear power plants and reactors
• Radiation protection
• Reactor siting criteria
• Reporting and recordkeeping requirements

For the reasons set out in the preamble and under the authority of the Atomic Energy Act of 1954, as amended; the Energy Reorganization Act of 1974, as amended; and 5 U.S.C. 552 and 553, the NRC is adopting the following amendments to 10 CFR part 50.

PART 50—DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES

1. The authority citation for part 50 continues to read as follows:

Authority: Secs. 102, 103, 104, 105, 161, 182, 183, 186, 189, 68 Stat. 936, 937, 938, 948, 953, 954, 955, 956, as amended, sec. 234, 83 Stat. 444, as amended (42 U.S.C. 2132, 2133, 2134, 2135, 2201, 2232, 2233, 2236, 2239, 2282); secs. 201, as amended, 202, 206, 88 Stat. 1242, as amended, 1244, 1246 (42 U.S.C. 5841, 5842, 5846); sec. 1704, 112 Stat. 2750 (44 U.S.C. 3504 note); Energy policy Act of 2005, Pub. L. No. 109-58, 119 Stat. 194 (2005). Section 50.7 also issued under Pub. L. 95-601, sec. 10, 92 Stat. 2951 as amended by Pub. L. 102-486, sec. 2902, 106 Stat. 3123 (42 U.S.C. 5841). Section 50.10 also issued under secs. 101, 185, 68 Stat. 955, as amended (42 U.S.C. 2131, 2235); sec. 102, Pub. L. 91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.13, 50.54(dd), and 50.103 also issued under sec. 108, 68 Stat. 939, as amended (42 U.S.C. 2138).

Sections 50.23, 50.35, 50.55, and 50.56 also issued under sec. 185, 68 Stat. 955 (42 U.S.C. 2235). Sections 50.33a, 50.55a and Appendix Q also issued under sec. 102, Pub. L. 91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.34 and 50.54 also issued under sec. 204, 88 Stat. 1245 (42 U.S.C. 5844). Sections 50.58, 50.91, and 50.92 also issued under Pub. L. 97-415, 96 Stat. 2073 (42 U.S.C. 2239). Section 50.78 also issued under sec. 122, 68 Stat. 939 (42 U.S.C. 2152). Sections 50.80-50.81 also issued under sec. 184, 68 Stat. 954, as amended (42 U.S.C. 2234). Appendix F also issued under sec. 187, 68 Stat. 955 (42 U.S.C. 2237).

2. In § 50.61a, paragraph (g) is amended by adding Table 7 directly after Table 6 to read as follows:

§ 50.61a

Alternate fracture toughness requirements for protection against pressurized thermal shock events.

* * * * *

(g) * * *

Table 7—Threshold Values for the Outlier Deviation Test (Significance Level = 1%)

Number of available data points (n)	Second largest allowable normalized residual value (r*)	Largest allowable normalized residual value (r*)
3	1.55	2.71
4	1.73	2.81
5	1.84	2.88
6	1.93	2.93
7	2.00	2.98
8	2.05	3.02
9	2.11	3.06
10	2.16	3.09
11	2.19	3.12
12	2.23	3.14
13	2.26	3.17
14	2.29	3.19
15	2.32	3.21

Dated at Rockville, Maryland, this 2nd day of March 2010.

For the Nuclear Regulatory Commission.

Michael T. Lesar,

Chief, Rulemaking and Directives Branch, Division of Administrative Services, Office of Administration.