[Federal Register Volume 82, Number 88 (Tuesday, May 9, 2017)]
[Notices]
[Pages 21568-21573]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-09369]


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NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-498 and 50-499; NRC-2016-0092]


STP Nuclear Operating Company, South Texas Project, Units 1 and 2

AGENCY: Nuclear Regulatory Commission.

ACTION: Environmental assessment and finding of no significant impact; 
issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing an 
environmental assessment (EA) prepared under the National Environmental 
Policy Act of 1969 (NEPA) and NRC's regulations. This EA summarizes the 
results of the NRC staff's environmental review, which evaluates the 
potential environmental impacts of granting exemptions from NRC 
regulations in response to a request from STP Nuclear Operating Company 
(STPNOC, the licensee) for Facility Operating License Nos. NPF-76 and 
NPF-80, for South Texas Project (STP), Units 1 and 2, respectively, 
located in Matagorda County, Texas. The regulatory exemptions, if 
granted, allow STPNOC to change the licensing basis loss-of-coolant 
accident analysis identified in the Updated Final Safety Analysis 
Report to use a risk-informed approach to address safety issues 
discussed in Generic Safety Issue (GSI)-191 and to close Generic Letter 
(GL) 2004-02.

DATES: May 9, 2017.

ADDRESSES: Please refer to Docket ID NRC-2016-0092 when contacting the 
NRC about the availability of information regarding this document. You 
may obtain publicly-available information related to this document 
using any of the following methods:
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2016-0092. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions, contact 
the individual listed in the FOR FURTHER INFORMATION CONTACT section of 
this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly-available documents online in the 
ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and 
then select ``Begin Web-based ADAMS Search.'' For problems with ADAMS, 
please contact the NRC's Public Document Room (PDR) reference staff at 
1-800-397-4209, 301-415-4737, or by email to [email protected]. For 
the convenience of the reader, the ADAMS accession numbers are provided 
in a table in the ``Availability of Documents'' section of this 
document.
     NRC's PDR: You may examine and purchase copies of public 
documents at the NRC's PDR, Room 01-F21, One White Flint North, 11555 
Rockville Pike, Rockville, Maryland 20852.

FOR FURTHER INFORMATION CONTACT: Lisa Regner, Office of Nuclear Reactor 
Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-
0001; telephone: 301-415-1906, email: [email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction and Background

    The NRC is considering a request to grant certain regulatory 
exemptions for Facility Operating License Nos. NPF-76 and NPF-80, 
issued to STPNOC for operation of STP, Units 1 and 2, located in 
Matagorda County, Texas, in accordance with section 50.12, ``Specific 
exemptions,'' of title 10 of the Code of Federal Regulations (10 CFR), 
``Application for amendment of license, construction permit, or early 
site permit.'' The regulatory exemptions would allow STPNOC to resolve 
concerns associated with GSI-191, ``Assessment of Debris Accumulation 
on PWR [Pressurized-Water Reactor] Sump Performance,'' and the 
associated GL 2004-02, ``Potential Impact of Debris Blockage on 
Emergency Recirculation during Design Basis Accidents at Pressurized-
Water Reactors,'' issued on September 13, 2004.
    Pursuant to 10 CFR 51.21, ``Criteria for and identification of 
licensing and regulatory actions requiring environmental assessments,'' 
the NRC has prepared an EA summarizing the findings of its NEPA review 
of the proposed action. The NRC concluded that the proposed action will 
have no significant environmental impact.
    The NRC published a draft EA on the proposed action for public 
comment in the Federal Register on May 4, 2016 (81 FR 26838) (ADAMS 
Accession No. ML16032A387). No comments were received.

Background

    The NRC established GSI-191 to determine whether the transport and 
accumulation of debris from a loss-of-coolant accident in the PWR 
containment structure would impede the operation of the emergency core 
cooling system (ECCS) or containment spray system (CSS). A loss-of-
coolant accident within the containment structure is assumed to be 
caused by a break in the primary coolant loop piping. Water discharged 
from the pipe break would collect on the containment structure floor 
and within the containment emergency sump. During this type of 
accident, the ECCS and CSS would initially draw cooling water from the 
refueling water storage tank. However, realigning the ECCS pumps to the 
containment structure emergency sump would provide long-term cooling of 
the reactor core. Therefore, successful long-term cooling depends on 
the ability of the containment structure emergency sump to provide 
adequate flow to the residual heat removal recirculation pumps for 
extended periods of time.
    One of the concerns addressed by the implementation of GSI-191 is 
that debris, such as insulation installed on piping and components, 
within the containment structure could be dislodged by a jet of water 
and steam from a loss-of-coolant accident. Water, along with debris, 
would accumulate at the bottom of the containment structure and flow 
towards the emergency sump pumps. Insulation and other fibrous material 
could block the emergency sump screens and suction strainers, which in 
turn could prevent the ability of the containment emergency sump to 
provide adequate flow to the residual heat removal recirculation pumps 
(for more information, see NUREG-0897, ``Containment Emergency Sump 
Performance'').
    The NRC issued GL 2004-02 to address this safety concern by 
requesting PWR licensees, pursuant to 10 CFR 50.54(f), to use an NRC-
approved methodology to perform a ``mechanistic evaluation of the 
potential for the adverse effects of post-accident

[[Page 21569]]

debris blockage and operation with debris-laden fluids to impede or 
prevent the recirculation functions of the ECCS and CSS following all 
postulated accidents for which the recirculation of these systems is 
required'' and submit this information to the NRC for evaluation.
    Subsequent to the issuance of GL 2004-02, the NRC staff identified 
another related concern with the potential for debris to bypass the 
sump strainers (even the new strainers) and enter the reactor core. 
This safety issue could result in the build-up of material on fuel 
assemblies and at the core inlet, inhibit heat transfer, and prevent 
adequate cooling of the reactor core. Since 2004, the NRC and industry 
have conducted tests to gain more information on this concern. In 2012, 
the NRC staff developed three options for resolution of GSI-191, which 
are discussed in SECY-12-0093, ``Closure Options for Generic Safety 
Issue 191, Assessment of Debris Accumulation on Pressurized-Water 
Reactor Sump Performance,'' dated July 9, 2012.
    The three options for demonstrating compliance with 10 CFR 50.46, 
``Acceptance criteria for emergency core cooling systems for light-
water nuclear power reactors,'' and considering the impact of debris on 
ECCS and CSS recirculation, are summarized as follows.
    1. Option 1 allows the use of approved models and test methods.
    2. Option 2 allows the industry to implement additional mitigating 
measures until resolution is completed and take additional time to 
resolve issues through further industry testing or use of a risk-
informed approach. Use of this option has two alternative methods, 
including Option 2B, chosen by STPNOC, which allows development of a 
risk-informed approach to quantify the risk associated with this 
generic issue and submit a request to the NRC for a license amendment.
    3. Option 3 allows the industry to separate the regulatory 
treatment of the sump strainer and in-vessel effects. The ECCS 
strainers will be evaluated using currently approved models, while in-
vessel effects will be addressed using a risk-informed approach.
    The STPNOC proposed to use Option 2 to demonstrate compliance with 
10 CFR 50.46, and 10 CFR part 50, appendix A, General Design Criterion 
(GDC) 35, ``Emergency core cooling,'' GDC 38, ``Containment heat 
removal,'' and GDC 41, ``Containment atmosphere cleanup,'' and to 
resolve GSI-191 for STP. The licensee proposed to use both a 
deterministic method, with plant-specific testing, and a risk-informed 
approach. Because, historically, the NRC staff has not allowed 
licensees to use a risk-informed approach to show compliance with the 
requirements of 10 CFR 50.46, and GDCs 35, 38, and 41, STPNOC requested 
exemptions from 10 CFR 50.46(a)(1) and the aforementioned GDCs, to 
allow the use of a risk-informed approach to resolve GSI-191. If 
approved, the proposed action would not authorize any modifications 
within the containment structure, physical changes to the ECCS, or 
other modifications to the plant. Rather, the proposed action would 
only allow the use of an alternate methodology to show compliance with 
the regulations that require ECCS and CSS function during certain loss-
of-coolant accident events.

II. Environmental Assessment

Description of the Proposed Action

    The proposed action is to amend Facility Operating License Nos. 
NPF-76 and NPF-80 for STP, Units 1 and 2, and to grant regulatory 
exemptions requested by STPNOC. The regulatory exemptions would allow 
STPNOC to change the licensing basis loss-of-coolant accident analysis 
identified in the Updated Final Safety Analysis Report to use a risk-
informed approach to address safety issues discussed in GSI-191 and to 
close GL 2004-02. If approved, no physical modifications to the nuclear 
plant or changes to reactor operations involving the ECCS would be 
required. The proposed action is in response to the licensee's 
application dated June 19, 2013, and supplemented by letters dated 
August 20, 2015, and April 13, 2016.

Need for the Proposed Action

    As the holder of Facility Operating License Nos. NPF-76 and NPF-80, 
STPNOC is expected to address the safety issues discussed in GSI-191 
and to close GL 2004-02 with respect to STP, Units 1 and 2. Consistent 
with SECY-12-0093, STPNOC chose an approach to use a risk-informed 
methodology. Since the NRC staff's position has long held that only 
deterministic or bounding calculations be used to show compliance with 
10 CFR 50.46, and GDCs 35, 38, and 41, the STPNOC has requested that 
the NRC grant certain regulatory exemptions for STP, Units 1 and 2.
Special Circumstances
    The NRC staff determined that special circumstances under 10 CFR 
51.21 exist to prepare an EA for the proposed action because STP is the 
pilot plant to propose a risk-informed approach to resolve GSI-191 as 
recognized in Staff Requirement Memorandum SECY 12-0093, ``Closure 
Options for Generic Safety Issue--191, Assessment of Debris 
Accumulation on Pressurized-Water Reactor Sump Performance,'' dated 
December 14, 2012. Because this is the first NRC review of the use of a 
risk-informed, instead of a deterministic, approach to determine that 
the ECCS and CSS structures, systems, and components will provide 
adequate cooling for the reactor core and containment during design-
basis accidents in accordance with 10 CFR 50.46 and GDCs 35, 38, and 
41, the NRC staff considered the issuance of an EA to be a prudent 
course of action that would further the purposes of NEPA.

Plant Site and Environs

    The STP is located on approximately 12,220 acres (4,945 hectares) 
in rural and sparsely populated Matagorda County, Texas, approximately 
70 miles (mi) [110 kilometers (km)] south-southwest of Houston. Nearby 
communities include Matagorda, approximately 8 mi (13 km) south of the 
site; the City of Palacios, 11 mi (18 km) west of the site; and Bay 
City, 13 mi (21 km) north of the site.
    The STP power plant consists of two four-loop Westinghouse PWR 
units. The reactor core of each unit heats water, which is pumped to 
four steam generators, where the heated water is converted to steam. 
The steam is then used to turn turbines, which are connected to 
electrical generators that produce electricity. A simplified drawing of 
a PWR can be viewed at http://www.nrc.gov/reactors/pwrs.html.
    The reactor, steam generators, and other components are housed in a 
concrete and steel containment structure (building). The containment 
structure is a reinforced concrete cylinder with a concrete slab base 
and hemispherical dome. A welded steel liner is attached to the inside 
face of the concrete shell to ensure a high degree of leak tightness. 
In addition, the 4-foot (1.2-meter)-thick concrete walls of the 
containment structure serve as a radiation shield. Additional 
information on the plant structures and systems, as well as the 
environmental impact statement for license renewal, can be found in 
NUREG-1437, Supplement 48, ``Generic Environmental Impact Statement for 
License Renewal of Nuclear Plants: Supplement 48 Regarding South Texas 
Project, Units 1 and 2.''

Environmental Impacts of the Proposed Action

    Radiological and non-radiological impacts on the environment that 
may

[[Page 21570]]

result from granting the regulatory exemptions are summarized in the 
following sections.
Radiological Impacts
Radioactive Gaseous and Liquid Effluents and Solid Waste
    The STP uses waste treatment systems to collect, process, recycle, 
and dispose of gaseous, liquid, and solid wastes that contain 
radioactive material in a safe and controlled manner within NRC and 
Environmental Protection Agency radiation safety standards. Granting 
the regulatory exemptions will not result in any physical changes to 
the nuclear plant or reactor operations that would affect the types and 
quantities of radioactive material generated during plant operations; 
therefore, there will be no changes to the plant radioactive waste 
treatment systems. A detailed description of the STP radioactive waste 
handling and disposal activities is contained in Chapter 2.1.2 of 
Supplement 48 to NUREG-1437.
Radioactive Gaseous Effluents
    The objectives of the STP gaseous waste management system (GWMS) 
are to process and control the release of radioactive gaseous effluents 
into the environment to be within the requirements of 10 CFR 20.1301, 
``Dose limits for individual members of the public,'' and to be 
consistent with the as low as is reasonably achievable (ALARA) dose 
objectives set forth in appendix I to 10 CFR part 50. The GWMS is 
designed so that radiation exposure to plant workers is within the dose 
limits in 10 CFR 20.1201, ``Occupational dose limits for adults.''
    Granting the regulatory exemptions will not result in any physical 
changes to the nuclear plant or reactor operations; therefore, there 
will be no changes to the GWMS. The existing equipment and plant 
procedures that control radioactive releases to the environment will 
continue to be used to maintain radioactive gaseous releases within the 
dose limits of 10 CFR 20.1301 and the ALARA dose objectives in appendix 
I to 10 CFR part 50.
Radioactive Liquid Effluents
    The function of the STP liquid waste processing system (LWPS) is to 
collect and process radioactive liquid wastes to reduce radioactivity 
and chemical concentrations to levels acceptable for discharge to the 
environment or to recycle the liquids for use in plant systems. The 
principal objectives of the LWPS are to collect liquid wastes that may 
contain radioactive material and to maintain sufficient processing 
capability so that liquid waste may be discharged to the environment 
below the regulatory limits of 10 CFR 20.1301 and consistent with the 
ALARA dose objectives in appendix I to 10 CFR part 50. The waste is 
routed through a monitor that measures the radioactivity and can 
automatically terminate the release in the event radioactivity exceeds 
predetermined levels. The liquid waste is discharged into the main 
cooling reservoir. The entire main cooling reservoir is within the STP 
site boundary and the public is prohibited from access to the area.
    Granting the regulatory exemptions will not result in any physical 
changes to the nuclear plant or reactor operations; therefore, there 
will be no changes to the LWPS. The existing equipment and plant 
procedures that control radioactive releases to the environment will 
continue to be used to maintain radioactive liquid releases within the 
dose limits of 10 CFR 20.1301 and the ALARA dose objectives in appendix 
I to 10 CFR part 50.
Radioactive Solid Wastes
    The function of the STP solid waste processing system (SWPS) is to 
process, package, and store the solid radioactive wastes generated by 
nuclear plant operations until they are shipped off site to a vendor 
for further processing or for permanent disposal at a licensed burial 
facility, or both. The storage areas have restricted access and 
shielding to reduce radiation rates to plant workers. The principal 
objectives of the SWPS are to package and transport the waste in 
compliance with NRC regulations in 10 CFR part 61, ``Licensing 
Requirements for Land Disposal of Radioactive Waste,'' and 10 CFR part 
71, ``Packaging and Transportation of Radioactive Material,'' and the 
U.S. Department of Transportation regulations in 49 CFR parts 170 
through 179; and to maintain the dose limits of 10 CFR 20.1201, 10 CFR 
20.1301, and appendix I to 10 CFR part 50.
    Granting the regulatory exemptions will not result in any physical 
changes to the nuclear plant or reactor operations; therefore, the 
waste can be handled by the SWPS without modification. The existing 
equipment and plant procedures that control radioactive solid waste 
handling will continue to be used to maintain exposures within the dose 
limits of 10 CFR 20.1201, 10 CFR 20.1301, and 10 CFR part 50, appendix 
I.
Occupational Radiation Doses
    The proposed action of granting the regulatory exemptions will not 
result in any physical changes being made to the nuclear plant or 
reactor operations; therefore, there will be no change to any in-plant 
radiation sources. The licensee's radiation protection program monitors 
radiation levels throughout the nuclear plant to establish appropriate 
work controls, training, temporary shielding, and protective equipment 
requirements so that worker doses will remain within the dose limits of 
10 CFR part 20, subpart C, ``Occupational Dose Limits.'' Granting the 
regulatory exemptions will not change radiation levels within the 
nuclear plant and, therefore, will have no increased radiological 
impact to the workers.
Offsite Radiation Dose
    The primary sources of offsite dose to members of the public from 
the STP are radioactive gaseous and liquid effluents. As discussed 
previously, there will be no change to the operation of the STP 
radioactive gaseous and liquid waste management systems or the ability 
to perform their intended functions. Also, there will be no change to 
the STP radiation monitoring system and procedures used to control the 
release of radioactive effluents in accordance with radiation 
protection standards in 10 CFR 20.1301, 40 CFR 190, ``Environmental 
Radiation Protection Standards for Nuclear Power Operations,'' and the 
ALARA dose objectives in appendix I to 10 CFR part 50.
    Based on the previous statements, the offsite radiation dose to 
members of the public would not change and would continue to be within 
regulatory limits, and, therefore, granting the regulatory exemptions 
will not change offsite dose levels and, consequently, the health 
effects of the proposed action will not be significant.
Design-Basis Accidents
    Design-basis accidents at STP, Units 1 and 2, are evaluated by both 
the licensee and the NRC to ensure that the units can withstand the 
spectrum of postulated accidents without undue hazard to the public 
health and safety and the protection of the environment.
    Separate from its environmental review in this EA, the NRC staff is 
evaluating the licensee's technical and safety analyses provided in 
support of the proposed action of granting the exemption requests to 
ensure that, following the proposed action, the licensee will continue 
to meet the NRC regulatory requirements for safe operation. The results 
and conclusion of the NRC staff's safety review will be documented in a 
publicly available safety evaluation. If the NRC staff concludes in 
this safety evaluation that taking the proposed action will (1)

[[Page 21571]]

provide reasonable assurance that the health and safety of the public 
will not be endangered by operation in the proposed manner, (2) provide 
reasonable assurance that such activities will be conducted in 
compliance with the Commission's regulations, and (3) not be inimical 
to the common defense and security or to the health and safety of the 
public, then the proposed action will also not have a significant 
environmental impact. The NRC will not take the proposed action absent 
such a safety conclusion.
Radiological Cumulative Impacts
    The radiological dose limits for protection of the public and plant 
workers have been developed by the NRC and the Environmental Protection 
Agency to address the cumulative impact of acute and long-term exposure 
to radiation and radioactive material. These dose limits are codified 
in 10 CFR part 20, ``Standards for Protection Against Radiation,'' and 
40 CFR part 190.
    Cumulative radiation doses are required to be within the limits set 
forth in the regulations cited in the previous paragraph. Granting the 
exemptions will not require any physical changes to the plant or plant 
activities, there will not be changes to in-plant radiation sources, 
and offsite radiation dose to members of the public will not change. 
Therefore, the NRC staff concludes that there would not be a 
significant cumulative radiological impact from the proposed action.
Radiological Impacts Summary
    Based on these radiological evaluations, the proposed action of 
granting the exemptions would not result in any significant 
radiological impacts. Therefore, if the NRC staff concludes in its 
separate safety evaluation that taking the proposed action will (1) 
provide reasonable assurance that the health and safety of the public 
will not be endangered by operation in the proposed manner, (2) provide 
reasonable assurance that such activities will be conducted in 
compliance with the Commission's regulations, and (3) not be inimical 
to the common defense and security or to the health and safety of the 
public, then the proposed action will not have a significant 
radiological impact.
Non-Radiological Impacts
    No physical modifications to the nuclear plant or changes to 
reactor operations involving the ECCS would be required if the NRC were 
to grant the regulatory exemptions. Also, no physical changes would be 
made to other structures or land use within the STP site. Non-
radiological liquid effluents or gaseous emissions would not change and 
therefore environmental conditions at the STP site also would not 
change. In addition, granting the regulatory exemptions would not 
result in changes to the use of resources (e.g., visual, terrestrial, 
or aquatic) or cause any new environmental impacts (e.g., noise). 
Further, granting the regulatory exemptions does not change the 
operation of the reactor, the heat load dissipated to the environment, 
or the amount of non-radiological waste.
    Therefore, there would be no non-radiological environmental impacts 
to any resource or any irreversible and irretrievable commitments of 
resources.
Non-Radiological Cumulative Impacts
    Since granting the regulatory exemptions would not result in 
environmental effects, there would be no cumulative impact.

Environmental Impacts of the Alternatives to the Proposed Action

    As discussed earlier, licensees have options in responding to GL 
2004-02 and demonstrating compliance with 10 CFR 50.46 considering the 
impacts of debris on the emergency core cooling system. Consistent with 
these options and as an alternative to the proposed action, the 
licensee could choose to not pursue exemptions (Options 1 and 3). 
Depending on the results of its analysis, the licensee would instead 
remove fibrous insulation to reduce the debris loading and the 
potential for clogging the containment sumps, and would replace 
insulation within the reactor containment building. This alternative 
would involve the physical removal and disposal of significant amounts 
of insulation from a radiation area within the reactor containment 
building and replacement with insulation less likely to impact sump 
performance. This would be considered the ``no action alternative'' in 
that it would not require exemptions (actions) from the NRC.
    Removal of the existing insulation from the containment building 
would generate radiologically contaminated waste. The STPNOC estimated 
that 4,620 cubic feet of insulation would be removed and stored onsite 
until disposal. The old insulation would require special handling and 
packaging so that it could be safely transported from the STP site. The 
licensee's existing low-level radioactive and hazardous waste handling 
and disposal activities would likely be used to process and store this 
waste material. The old insulation would then be transported to a low-
level radioactive or hazardous waste disposal site. Energy (fuel) would 
be expended to transport the insulation and land would be expended at 
the disposal site.
    The removal of the old insulation and installation of the new 
insulation would expose workers to radiation. In its application, 
STPNOC estimates that this would result in an additional collective 
radiation exposure of 158-176 person-roentgen equivalent man (rem) over 
its baseline collective radiation exposure. The NRC staff reviewed 
NUREG-0713, Volume 34, ``Occupational Radiation Exposure at Commercial 
Nuclear Power Reactors and Other Facilities 2012: Forty-Fifth Annual 
Report,'' and determined that STPNOC's average baseline collective 
radiation exposure is approximately 90 person-rem. This additional 158-
176 person-rem collective exposure would be shared across the entire 
work force involved with removing and reinstalling insulation.
    In SECY-12-0093, the NRC staff attempted to develop a total 
occupational dose estimate for the work involved in insulation removal 
and replacement associated with GSI-191. Due to uncertainties in the 
scope of work required to remove and replace insulation at a specific 
nuclear plant and other site-specific factors such as source term and 
hazardous materials, the NRC staff was unable to estimate the total 
occupational dose associated with this work. However, dose estimates 
were provided by the Nuclear Energy Institute (NEI) in a letter to the 
NRC dated March 30, 2012, based on information collected on 
occupational radiation exposures that have been, or could be, incurred 
during insulation removal and replacement. In the letter, NEI noted 
similar difficulties to those experienced by the NRC staff in 
estimating the potential amount of radiation exposure, but provided a 
``per unit'' estimate of between 80 to 525 person-rem. The NRC staff 
ultimately concluded that the NEI estimates were reasonable given the 
uncertainties in the scope of work and other nuclear plant site-
specific factors such as source term and hazardous materials. 
Therefore, since STPNOC's estimate of radiation exposure for insulation 
removal and replacement is within the NEI estimated range, the NRC 
staff considers STPNOC's estimate of an increase of 158-176 person-rem 
over the baseline exposure to be reasonable.
    As stated in the ``Occupational Radiation Doses'' section of this 
document, STPNOC's radiation protection program monitors radiation 
levels throughout the nuclear plant to establish appropriate work 
controls,

[[Page 21572]]

training, temporary shielding, and protective equipment requirements so 
that worker doses are expected to remain within the dose limits of 10 
CFR 20.1201.
    In addition, as stated in the ``Offsite Radiation Dose'' section of 
this document, STPNOC also has a radiation monitoring system and 
procedures in place to control the release of radioactive effluents in 
accordance with radiation protection standards in 10 CFR 20.1301, 40 
CFR part 190, and the ALARA dose objectives in appendix I to 10 CFR 
part 50. Therefore, radiation exposure to members of the public would 
not be significant and would be maintained within the NRC dose criteria 
in 10 CFR 20.1301, 40 CFR part 190, and the ALARA dose objectives of 
appendix I to 10 CFR part 50.
    Based on this information, impacts to members of the public from 
removing and replacing insulation within the reactor containment 
building would not be significant. However, impacts to plant workers 
and the environment from implementing this alternative would be greater 
than implementing the proposed action.

Alternative Use of Resources

    The proposed action would not involve the use of any different 
resources (e.g., water, air, land, nuclear fuel) not previously 
considered in NUREG-1437, Supplement 48.

Agencies and Persons Consulted

    In accordance with its stated policy, on May 1, 2017, the NRC staff 
consulted with the Texas State official, Mr. Robert Free, regarding the 
final environmental impact of the proposed action. The state official 
had no comments on the final EA and finding of no significant impact.

III. Finding of No Significant Impact

    The NRC is considering STPNOC's requests to amend Facility 
Operating License Nos. NPF-76 and NPF-80 for STP, Units 1 and 2, and to 
grant exemptions for STP, Units 1 and 2, from certain requirements of 
10 CFR 50.46(a)(1), and 10 CFR part 50, appendix A, GDCs 35, 38, and 
41.
    This proposed action would not result in changes to radioactive 
effluents or emissions to nuclear plant workers and members of the 
public or any changes to radiological and non-radiological impacts to 
the environment. On the basis of the EA included in Section II of this 
notice and incorporated by reference in this finding, the NRC staff 
finds that the proposed action will not have a significant effect on 
the quality of the human environment. The NRC staff's evaluation 
considered the information provided in the licensee's application as 
supplement, and the NRC staff's review of related environmental 
documents. Section IV below lists the environmental documents related 
to the proposed action and includes information on the availability of 
the documents. Accordingly, the NRC has determined not to prepare an 
environmental impact statement for the proposed action.

IV. Availability of Documents

    The documents identified in the following table are available for 
public inspection through the NRC's Agencywide Documents Access and 
Management System (ADAMS) or by using one of the methods discussed in 
Section I.A, ``Obtaining Information,'' of this document.

------------------------------------------------------------------------
             Title                    Date         ADAMS Accession No.
------------------------------------------------------------------------
NUREG-0897, Containment                 10/1985  ML112440046
 Emergency Sump Performance:
 Technical Findings Related to
 Unresolved Safety Issue A-43,
 Revision 1.
NRC Generic Letter 2004-02,           9/13/2004  ML042360586
 Potential Impact of Debris
 Blockage on Emergency
 Recirculation During Design
 Basis Accidents at Pressurized-
 Water Reactors.
NEI letter to NRC, Nuclear           03/30/2012  ML12095A319
 Energy Institute, GSI-191 Dose
 Estimates.
Commission SECY-12-0093,             07/09/2012  ML121320270
 Closure Options for Generic                     (package)
 Safety Issue-191, Assessment
 of Debris Accumulation on
 Pressurized-Water Reactor Sump
 Performance.
Commission SRM-SECY-12-0093,         12/14/2012  ML12349A378
 Staff Requirements--SECY-12-
 0093--Closure Options for
 Generic Safety Issue-191,
 Assessment of Debris
 Accumulation on Pressurized-
 Water Reactor Sump Performance.
STPNOC letter to NRC, STP Pilot      01/31/2013  ML13043A013
 Submittal and Request for
 Exemption for a Risk-Informed
 Approach to Resolve Generic
 Safety Issue (GSI)-191.
NRC letter to STPNOC, South          04/01/2013  ML13066A519
 Texas Project, Units 1 and 2--
 Supplemental Information
 Needed for Acceptance of
 Requested Licensing Action Re:
 Request for Exemption for a
 Risk-Informed Approach to
 Resolve Generic Safety Issue
 191.
STPNOC letter to NRC, Revised        06/19/2013  ML131750250
 STP Pilot Submittal and                         (package)
 Requests for Exemptions and
 License Amendment for a Risk-
 Informed Approach to Resolving
 Generic Safety Issue (GSI)-191.
STPNOC letter to NRC,                10/03/2013  ML13295A222
 Corrections to Information
 Provided in Revised STP Pilot
 Submittal and Requests for
 Exemptions and License
 Amendment for a Risk-Informed
 Approach to Resolving Generic
 Safety Issue (GSI)-191.
STPNOC letter to NRC, Submittal      10/31/2013  ML13323A673
 of GSI-191 Chemical Effects                     (package)
 Test Reports.
STPNOC letter to NRC,                11/13/2013  ML13323A128
 Supplement 1 to Revised STP                     (package)
 Pilot Submittal and Requests
 for Exemptions and License
 Amendment for a Risk-Informed
 Approach to Resolving Generic
 Safety Issue (GSI)-191.
STPNOC letter to NRC,                11/21/2013  ML13338A165
 Supplement 1 to Revised STP
 Pilot Submittal for a Risk-
 Informed Approach to Resolving
 Generic Safety Issue (GSI)-191
 to Supersede and Replace the
 Revised Pilot Submittal.
NUREG-1437, Supplement 48,              11/2013  ML13322A890
 Generic Environmental Impact
 Statement for License Renewal
 of Nuclear Plants: Supplement
 48 Regarding South Texas
 Project, Units 1 and 2: Final
 Report.
STPNOC letter to NRC, Response       12/23/2013  ML14015A312
 to STP-GSI-191 EMCB-RAI-1.
STPNOC letter to NRC, Response       12/23/2013  ML14015A311
 to NRC Request for Reference
 Document For STP Risk-Informed
 GSI-191 Application.
STPNOC letter to NRC, Response       03/17/2014  ML14086A383
 to NRC Accident Dose Branch                     (package)
 Request for Additional
 Information.
STPNOC letter to NRC, Response       01/09/2014  ML14029A533
 to Request for Additional
 Information re Use of RELAP5
 in Analyses for Risk-Informed
 GSI-191 Licensing Application.
STPNOC letter to NRC, Submittal      02/13/2014  ML14052A110 (package,
 of CASA Grande Code and                          portions redacted)
 Analyses for STP's Risk-
 Informed GSI-191 Licensing
 Application.

[[Page 21573]]

 
STPNOC letter to NRC, Submittal      02/27/2014  ML14072A075
 of GSI-191 Chemical Effects                     (package)
 Test Reports.
NRC Letter to STPNOC, Request        04/15/2014  ML14087A075
 for Additional Information,
 Round 1.
NUREG-0713, Volume 34,                  04/2014  ML14126A597
 Occupational Radiation
 Exposure at Commercial Nuclear
 Power Reactors and Other
 Facilities 2012: Forty-Fifth
 Annual Report.
STPNOC letter to NRC, Second         05/15/2014  ML14149A354
 Submittal of CASA Grande
 Source Code for STP's Risk-
 Informed GSI-191 Licensing
 Application.
STPNOC letter to NRC, First Set      05/22/2014  ML14149A439
 of Responses to April, 2014,                    (package)
 Requests for Additional
 Information Regarding STP Risk-
 Informed GSl-191 Licensing
 Application--Revised.
STPNOC letter to NRC, Second         06/25/2014  ML14178A467
 Set of Responses to April,                      (package)
 2014, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application.
STPNOC letter to NRC, Third Set      07/15/2014  ML14202A045
 of Responses to April, 2014,
 Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application.
NRC letter to STPNOC, Request        03/03/2015  ML14357A171
 for Additional Information,
 Round 2.
STPNOC letter to NRC, Submittal      03/10/2015  ML15072A092
 of Updated CASA Grande Input
 for STP's Risk-Informed GSI-
 191 Licensing Application.
STPNOC letter to NRC,                03/25/2015  ML15091A440
 Description of Revised Risk-
 Informed Methodology and
 Responses to Round 2 Requests
 for Additional Information
 Regarding STP Risk-Informed
 GSI-191 Licensing Application.
STPNOC letter to NRC,                08/20/2015  ML15246A125
 Supplement 2 to STP Pilot                       (package)
 Submittal and Requests for
 Exemptions and License
 Amendment for a Risk-Informed
 Approach to Address Generic
 Safety Issue (GSI)-191 and
 Respond to Generic Letter (GL)
 2004-02.
NRC letter to STPNOC, Request        04/11/2016  ML16082A507
 for Additional Information,
 Round 3 (without Risk).
NRC letter to STPNOC, Request        05/26/2016  ML16125A290
 of Additional Information,
 Round 3 (Risk).
STPNOC letter to NRC, First Set      05/11/2016  ML16154A117
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSl-191 Licensing
 Application.
STPNOC letter to NRC,                06/09/2016  ML16176A148
 Applicability of Application
 Supplement 1 Correspondence to
 Supplement 2 Regarding STP
 Risk-Informed GSI-191
 Licensing Application.
STPNOC letter to NRC, Second         06/16/2016  ML16196A241
 Set of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application.
STPNOC letter to NRC, Third Set      07/18/2016  ML16209A226
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application--Part A.
STPNOC letter to NRC, Third Set      07/21/2016  ML16229A189
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application--Part B.
STPNOC letter to NRC, Third Set      07/21/2016  ML16230A232
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application--Part C.
STPNOC letter to NRC, Third Set      07/28/2016  ML16221A393
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application--Part D.
STPNOC letter to NRC, Third Set      09/12/2016  ML16272A162
 of Responses to April 11,
 2016, Requests for Additional
 Information Regarding STP Risk-
 Informed GSI-191 Licensing
 Application--Part E.
STPNOC letter to NRC,                10/20/2016  ML16302A015
 Supplement 3 to Revised Pilot
 Submittal and Requests for
 Exemptions and License
 Amendment for a Risk-Informed
 Approach to Address Generic
 Safety Issue (GSl)-191 and
 Respond to Generic Letter (GL)
 2004-02.
STPNOC letter to NRC, Response        11/9/2016  ML16321A407
 to Request for Additional
 Information Regarding
 Sensitivity Studies for STPNOC
 Risk-Informed Pilot GSl-191
 Application.
STPNOC letter to NRC, Revised         12/7/2016  ML16365A006
 Applicability Matrix for
 Response to Request for
 Additional Information
 Questions APLA-1a and APLA-1b
 Regarding STP Risk-Informed
 GSl-191 Licensing Application.
STPNOC letter to NRC, Response       01/19/2017  ML17025A123
 to Request for Additional
 Information on Revised
 Applicability Matrix for
 Questions Regarding Risk-
 Informed GSI-191 Licensing
 Application.
------------------------------------------------------------------------


    Dated at Rockville, Maryland, this 2nd day of May, 2017.
    For the Nuclear Regulatory Commission.
Robert J. Pascarelli,
Chief, Plant Licensing Branch IV, Division of Operating Reactor 
Licensing, Office of Nuclear Reactor Regulation.
[FR Doc. 2017-09369 Filed 5-8-17; 8:45 am]
BILLING CODE 7590-01-P