[Federal Register Volume 62, Number 28 (Tuesday, February 11, 1997)]
[Notices]
[Pages 6278-6279]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-3322]


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NUCLEAR REGULATORY COMMISSION
[Docket 70-7002]


Notice of Amendment to Certificate of Compliance GDP-2 for the 
U.S. Enrichment Corporation, Portsmouth Gaseous Diffusion Plant, 
Portsmouth, OH

    The Director, Office of Nuclear Material Safety and Safeguards, has 
made a determination that the following amendment request is not 
significant in accordance with 10 CFR 76.45. In making that 
determination, the staff concluded that: (1) There is no change in the 
types or significant increase in the amounts of any effluents that may 
be released offsite; (2) there is no significant increase in individual 
or cumulative occupational radiation exposure; (3) there is no 
significant construction impact; (4) there is no significant increase 
in the potential for, or radiological or chemical consequences from, 
previously analyzed accidents; (5) the proposed changes do not result 
in the possibility of a new or different kind of accident; (6) there is 
no significant reduction in any margin of safety; and (7) the proposed 
changes will not result in an overall decrease in the effectiveness of 
the plant's safety, safeguards, or security programs. The basis for 
this determination for the amendment request is described below.
    The NRC staff has reviewed the certificate amendment application 
and concluded that it provides reasonable assurance of adequate safety, 
safeguards, and security and compliance with NRC requirements. 
Therefore, the Director, Office of Nuclear Material
    Safety and Safeguards, is prepared to issue an amendment to the 
Certificate of Compliance for the Portsmouth Gaseous Diffusion Plant 
(PORTS). The staff has prepared a Compliance Evaluation Report which 
provides details of the staff's evaluation.
    The NRC staff has determined that this amendment satisfies the 
criteria for a categorical exclusion in accordance with 10 CFR 51.22. 
Therefore, pursuant to 10 CFR 51.22(b), no environmental impact 
statement or environmental assessment need be prepared for this 
amendment.
    USEC or any person whose interest may be affected may file a 
petition, not exceeding 30 pages, requesting review of the Director's 
Decision. The petition must be filed with the Commission not later than 
15 days after publication of this Federal Register Notice. A petition 
for review of the Director's Decision shall set forth with 
particularity the interest of the petitioner and how that interest may 
be affected by the results of the decision. The petition should 
specifically explain the reasons why review of the Decision should be 
permitted with particular reference to the following factors: (1) The 
interest of the petitioner; (2) how that interest may be affected by 
the Decision, including the reasons why the petitioner should be 
permitted a review of the Decision; and (3) the petitioner's areas of 
concern about the activity that is the subject matter of the Decision. 
Any person described in this paragraph (USEC or any person who filed a 
petition) may file a response to any petition for review, not to exceed 
30 pages, within 10 days after filing of the petition. If no petition 
is received within the designated 15-day period, the Director will 
issue the final amendment to the Certificate of Compliance without 
further delay. If a petition for review is received, the decision on 
the amendment application will become final in 60 days, unless the 
Commission grants the petition for review or otherwise acts within 60 
days after publication of this Federal Register Notice.
    A petition for review must be filed with the Secretary of the 
Commission, U.S. Nuclear Regulatory Commission, Washington, DC 20555-
0001, Attention: Docketing and Services Branch, or may be delivered to 
the Commission's Public Document Room, the Gelman Building, 2120 L 
Street, NW, Washington, DC, by the above date.
    For further details with respect to the action see: (1) The 
application for amendment and (2) the Commission's Compliance 
Evaluation Report. These items 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.
    Date of amendment request: November 8, 1996, as modified by USEC 
responses dated December 13, 1996, and January 16, 1997, to NRC 
requests for additional information dated November 29, 1996, and 
December 31, 1996, respectively.
    Brief description of amendment: The amendment changes the Technical 
Safety Requirement (TSR) Standby Operational Mode definition for the 
UF6 Withdrawal Stations by allowing the compression loop vent path to 
the cascade to be open. It should be noted that venting of the 
Withdrawal Station compression loop to the cascade is routinely done at 
PORTS. However, accounting for this procedure was inadvertently left 
out of the Standby Operational Mode definition by USEC from its 
proposed TSRs which have been approved by the NRC.
    Basis for finding of no significance:
    1. The proposed amendment will not result in a change in the types 
or significant increase in the amounts of any effluents that may be 
released offsite.
    The proposed change to TSR 2.5.1 permits evacuating UF6 from the 
compression loop in the UF6 withdrawal station to the cascade, which 
acts as a low pressure sink, in the Standby Operational Mode. This 
change will not result in significantly increasing the potential for 
unconfinement of UF6 which could lead to an increase in effluents that 
may be released offsite since it only involves venting of UF6 from one 
portion of process piping, which confines UF6 in the Withdrawal 
Station, to another portion of process piping which confines UF6 in the 
enrichment cascade. Confinement of UF6 within the cascade is primarily 
provided by maintaining the cell high-side (compressor discharge) gas 
pressure below 25 psia (TSR 2.2.3.13) and by applying appropriate 
quality assurance requirements to process gas piping and equipment 
(Safety Analysis Report Section 3.8.2.2). Therefore, this TSR amendment 
will not result in significant amounts of effluents that may be 
released offsite.
    2. The proposed amendment will not result in a significant increase 
in individual or cumulative occupational radiation exposure.
    Evacuating UF6 from the compression loop to the cascade in the 
Standby Operational Mode will not significantly impart additional 
occupational radiation exposure. The cascade or the withdrawal loops do 
not result in significant occupational radiation exposures. Some of the 
reasons being that: (1) The occupancy factor is low, (2) distance from 
the source is generally high, (3) significant shielding is provided by 
piping and equipment, (4) depleted and low enriched uranium has low 
specific activities and are also comparatively low gamma radiation 
emitters, (5) most of the uranium is in gaseous form (low density), and 
(6) UF6 is confined within quality controlled equipment and piping. 
Therefore, any transfer of confined UF6 from the withdrawal station to 
the cascade would not measurably modify individual or

[[Page 6279]]

cumulative occupational radiation exposures.
    3. The proposed amendment will not result in a significant 
construction impact.
    Since the proposed changes do not involve any construction, 
therefore, there will be no construction impacts.
    4. The proposed amendment will not result in a significant increase 
in the potential for, or radiological or chemical consequences from, 
previously analyzed accidents.
    The proposed changes which involve evacuating UF6 from the 
compression loop to the cascade (low pressure sink) in the Standby 
Operational Mode will not result in a significant increase in the 
potential for UF6 releases. In fact, venting the compression loop to 
the cascade may enhance safety by minimizing the potential for over-
pressurization of the UF6 withdrawal loop with subsequent confinement 
rupture. To avoid enrichment losses, UF6 is vented back to the A-
suction of a compressor in the cascade that has UF6 of similar 
enrichment. All A-suction pressures in lines that would receive the 
vented UF6 are subatmospheric. Therefore, any confinement failure would 
likely result in inleakage as opposed to outleakage. In addition, 
cascade units that would receive vented UF6 would likely be comprised 
of relatively smaller sized equipment containing relatively smaller 
quantities of UF6 since they would be located near the top and at the 
bottom of the cascade. Therefore, the proposed change will not result 
in a significant increase in the potential for UF6 releases.
    Going from a closed compression loop vent path to an open 
compression loop vent path will not result in a significant increase 
for, or radiological consequences from, previously evaluated 
criticality accidents. The likelihood of an accidental criticality in 
the cascade due to wet-air (moderator) inleakage would not be increased 
significantly for the following reasons:
    a. This amendment involves a valve that is internal to several 
valves even when the pigtail is not attached to the withdrawal 
manifold. These valves would be in the closed position. Therefore, 
several misvalving errors would be required to permit significant wet-
air inleakage into the cascade through the compression loop vent valve.
    b. To maintain the integrity of the UF6 pressure boundary, USEC is 
committed to applying appropriate quality assurance requirements to 
process gas piping and equipment (including valves) with diameters of 2 
inches or larger.
    c. Formation of UO2F2 in the cascade due to significant inleakage 
of wet-air would result in compressor vibration and would reduce 
barrier permeability thus affecting cascade compressor performance 
which would be observed in the control rooms via motor load 
indications. Changes in compressor A-suction pressures would also be 
detected.
    d. Introduction of wet-air into the cascade would be detected on 
the line recorders that continuously indicate nitrogen and oxygen 
concentrations.
    Based on the primary reasons provided above, the proposed TSR 
change will also not significantly raise the probability or 
consequences of a criticality accident.
    5. The proposed amendment will not result in the possibility of a 
new or different kind of accident.
    For similar reasons provided in the assessment of criterion 4, 
evacuating UF6 from the compression loop to the cascade in the Standby 
Operational Mode will not result in a new potential accident involving 
UF6 releases or criticality. In fact, venting the compression loop to 
the cascade may enhance safety by minimizing the potential for over-
pressurization of the UF6 withdrawal loop with subsequent confinement 
rupture.
    6. The proposed amendment will not result in a significant 
reduction in any margin of safety.
    As discussed above, from a UF6 release accident standpoint, venting 
to the cascade may enhance safety, and from a criticality accident 
standpoint, the safety impact is insignificant. This procedure, which 
is routine operation at PORTS, will not result in the violation of any 
limiting condition of operation. Therefore, the opening of the vent 
pathway in the Standby Operational Mode will not significantly reduce 
any margin of safety.
    7. The proposed amendment will not result in an overall decrease in 
the effectiveness of the plant's safety, safeguards, or security 
programs.
    As discussed above, from a UF6 confinement standpoint venting to 
the cascade may enhance the plant's safety program and from a 
criticality safety program standpoint, the safety impact is 
insignificant.
    The staff has not identified any safeguards or security related 
implications from the proposed amendment. Therefore, the opening of the 
vent pathway in the Standby Operational Mode will not result in an 
overall decrease in the effectiveness of the plant's safety, 
safeguards, or security programs.
    Effective date: This amendment becomes effective at 12:00 noon on 
the day following the day issued.
    Certificate of Compliance No. GDP-2: Amendment will revise the 
Technical Safety Requirements.
    Local Public Document Room location: Portsmouth Public Library, 
1220 Gallia Street, Portsmouth, Ohio 45662.

    Dated at Rockville, Maryland, this 4th day of February 1997.

    For the Nuclear Regulatory Commission.
Carl J. Paperiello,
Director, Office of Nuclear Material Safety and Safeguards.
[FR Doc. 97-3322 Filed 2-10-97; 8:45 am]
BILLING CODE 7590-01-P