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[Federal Register Volume 62, Number 232 (Wednesday, December 3, 1997)]
[Proposed Rules]
[Pages 63911-63912]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-31732]

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NUCLEAR REGULATORY COMMISSION

10 CFR Parts 50 and 70

RIN 3150-AF87

Criticality Accident Requirements

AGENCY: Nuclear Regulatory Commission.

ACTION: Proposed rule.

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SUMMARY: The Nuclear Regulatory Commission (NRC) is amending its 
regulations to provide light-water nuclear power reactor licensees with 
greater flexibility in meeting the requirement that licensees 
authorized to possess more than a small amount of special nuclear 
material (SNM) maintain a criticality monitoring system in each area 
where the material is handled, used, or stored. This action is taken as 
a result of the experience gained in processing and evaluating a number 
of exemption requests from power reactor licensees and NRC's safety 
assessments in response to these requests that concluded that the 
likelihood of criticality was negligible.

DATES: Comments on the proposed rule must be received on or before 
January 2, 1998.

ADDRESSES: Mail comments to: Secretary, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, Attention: Rulemaking and 
Adjudication Staff. Hand deliver comments to 11555 Rockville Pike, 
Maryland, between 7:45 am and 4:15 pm on Federal workdays.
    Copies of any comments received may be examined at the NRC Public 
Document Room, 2120 L Street NW. (Lower Level), Washington, DC.
    For information on submitting comments electronically, see the 
discussion under Electronic Access in the Supplementary Information 
section.

FOR FURTHER INFORMATION CONTACT: Stan Turel, Office of Nuclear 
Regulatory Research, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001, telephone (301) 415-6234, e-mail [email protected].

SUPPLEMENTARY INFORMATION: For additional information see the Direct 
Final Rule published in the rules section of this Federal Register.

Procedural Background

    Because NRC considers this action noncontroversial and routine, we 
are publishing this proposed rule concurrently as a direct final rule. 
The direct final rule will become effective on February 17, 1998. 
However, if the NRC receives significant adverse comments on the direct 
final rule by January 2, 1998, then the NRC will publish a document 
that withdraws the direct final rule. If the direct final rule is 
withdrawn, the NRC will address in a Final Rule the comments received 
in response to the proposed revisions in a subsequent final rule. 
Absent significant modifications to the proposed revisions requiring 
republication, the NRC will not initiate a second comment period for 
this action in the event the direct final rule is withdrawn.

Electronic Access

    You may also provide comments via the NRC's interactive rulemaking 
web site through the NRC home page (http://www.nrc.gov). This site 
provides the availability to upload comments as files (any format), if 
your web browser supports that function. For information about the 
interactive rulemaking site, contact Ms. Carol Gallagher, (301) 415-
6215; e-mail [email protected]

List of Subjects

10 CFR Part 50

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

10 CFR Part 70

    Criminal penalties, Hazardous materials transportation, Material 
control and accounting, Nuclear materials, Packaging and containers, 
Radiation protection, Reporting and recordkeeping requirements, 
Scientific equipment, Security measures, Special nuclear material.

    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, the National Environmental Policy Act of 1969, 
as amended, and 5 U.S.C. 553, the NRC is considering adopting the 
following amendments to 10 CFR Parts 50 and 70.

PART 50--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION 
FACILITIES

    1. The authority citation for 10 CFR 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).
    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. 5851). Sections 50.10 also issued under secs. 101, 185, 68 
Stat. 936, 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. Section 50.68 is added under the center heading ``Issuance, 
Limitations, and Conditions of Licenses and Construction Permits'' to 
read as follows:

[[Page 63912]]

Sec. 50.68  Criticality accident requirements.

    (a) Each holder of a construction permit or operating license for a 
nuclear power reactor issued under this part, or a combined license for 
a nuclear power reactor issued under part 52 of this chapter shall 
comply with either 10 CFR 70.24 of this chapter or requirements in 
paragraph (b).
    (b) Each licensee shall comply with the following requirements in 
lieu of maintaining a monitoring system capable of detecting a 
criticality as described in 10 CFR 70.24:
    (1) Plant procedures may not permit handling and transportation at 
any one time of more fuel assemblies than have been determined to be 
safely subcritical under the most adverse moderation conditions 
feasible by unborated water.
    (2) The estimated ratio of neutron production to neutron absorption 
and leakage (k-effective) of the fresh fuel in the fresh fuel storage 
racks shall be calculated assuming the racks are loaded with fuel of 
the maximum permissible U-235 enrichment and flooded with pure water 
and must not exceed 0.95, at a 95 percent probability, 95 percent 
confidence level.
    (3) If optimum moderation of fresh fuel in the fresh fuel storage 
racks occurs when the racks are assumed to be loaded with fuel of the 
maximum permissible U-235 enrichment and filled with low-density 
hydrogenous fluid, the k-effective corresponding to this optimum 
moderation must not exceed 0.98, at a 95 percent probability, 95 
percent confidence level.
    (4) If no credit for soluble boron is taken, the k-effective of the 
spent fuel storage racks loaded with fuel of the maximum permissible U-
235 enrichment must not exceed 0.95, at a 95 percent probability, 95 
percent confidence level, if flooded with pure water. If credit is 
taken for soluble boron, the k-effective of the spent fuel storage 
racks loaded with fuel of the maximum permissible U-235 enrichment must 
not exceed 0.95, at a 95 percent probability, 95 percent confidence 
level, if flooded with borated water, and the k-effective must remain 
below 1.0 (subcritical), at a 95 percent probability, 95 percent 
confidence level, if flooded with pure water.
    (5) The quantity of SNM, other than nuclear fuel stored on site, is 
less than the quantity necessary for a critical mass.
    (6) Radiation monitors, as required by GDC 63, are provided in 
storage and associated handling areas when fuel is present to detect 
excessive radiation levels and to initiate appropriate safety actions.
    (7) The maximum nominal U-235 enrichment of the fresh fuel 
assemblies is limited to no greater than five (5.0) percent by weight.

PART 70--DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL

    1. The authority citation for 10 CFR Part 70 continues to read as 
follows:

    Authority: Secs. 51, 53, 161, 182, 183, 68 Stat. 929, 930, 948, 
953, 954, as amended, sec. 234, 83 Stat. 444, as amended, sec. 1701, 
106 Stat. 2951, 2952, 2953 (42 U.S.C. 2071, 2073, 2201, 2232, 2233, 
2282, 2297f); secs. 201, as amended, 202, 204, 206, 88 Stat. 1242, 
as amended, 1244, 1245, 1246, (42 U.S.C. 5841, 5842, 5845, 5846).
    Sections 70.1(c) and 70.20a(b) also issued under secs. 135, 141, 
Pub. L. 97-425, 96 Stat. 2232, 2241 (42 U.S.C. 10155, 10161). 
Section 70.7 also issued under Pub. L. 95-601, sec. 10, 92 Stat. 
2951 (42 U.S.C. 5851). Section 70.21(g) also issued under sec. 122, 
68 Stat. 939 (42 U.S.C. 2152). Section 70.31 also issued under sec. 
57d, Pub. L. 93-377, 88 Stat. 475 (42 U.S.C. 2077). Sections 70.36 
and 70.44 also issued under sec. 184, 68 Stat. 954, as amended (42 
U.S.C. 2234).
    Section 70.61 also issued under secs. 186, 187, 68 Stat. 955 (42 
U.S.C. 2236, 2237). Section 70.62 also issued under sec. 108, 68 
Stat. 939, as amended (42 U.S.C. 2138).

    2. In Sec. 70.24, paragraph (d) is revised to read as follows:

Sec. 70.24  Criticality accident requirements.

* * * * *
    (d) The requirements in paragraph (a) through (c) of this section 
do not apply to holders of a construction permit or operating license 
for a nuclear power reactor issued pursuant to part 50 of this chapter, 
or combined licenses issued under part 52 of this chapter, if the 
holders comply with the requirements of paragraph (b) of 10 CFR 50.68 
of this chapter.

    Dated at Rockville, Maryland this 14th day of November, 1997.

    For the Nuclear Regulatory Commission.
L. Joseph Callan,
Executive Director for Operations.
[FR Doc. 97-31732 Filed 12-2-97; 8:45 am]
BILLING CODE 7590-01-P
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