[Federal Register Volume 69, Number 184 (Thursday, September 23, 2004)]
[Proposed Rules]
[Pages 56958-56961]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-21337]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 69, No. 184 / Thursday, September 23, 2004 /
Proposed Rules
[[Page 56958]]
NUCLEAR REGULATORY COMMISSION
10 CFR Part 50
[Docket No. PRM-50-78]
Robert H. Leyse; Denial of Petition for Rulemaking
AGENCY: Nuclear Regulatory Commission.
ACTION: Petition for rulemaking; denial.
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SUMMARY: The Nuclear Regulatory Commission (NRC) is denying a petition
for rulemaking submitted by Mr. Robert H. Leyse (PRM-50-78). The
petitioner requested that the NRC's regulations governing domestic
licensing of production and utilization facilities and associated
guidance be amended to address the impact of fouling on the performance
of all heat exchange surfaces in a nuclear power plant. The petitioner
further stated that the fouling of heat transfer surfaces is not
adequately considered in licensing and compliance inspections, testing
programs, and computer codes used for nuclear power facilities.
ADDRESSES: Copies of the petition for rulemaking, the public comments
received, and the NRC's letter of denial to the petitioner may be
examined, and/or copied for a fee, at the NRC's Public Document Room,
located at One White Flint North, 11555 Rockville Pike, Public File
Area O1F21, Rockville, Maryland. These documents are also available
electronically at the NRC's Public Electronic Reading Room on the
Internet at http://www.nrc.gov/reading-rm/adams.html. From this site,
the public can gain entry into the Agencywide Document Access and
Management System (ADAMS), which provides text and image files of NRC's
public documents. For further information contact the PDR reference
staff at (800) 387-4209 or (301) 415-4737 or by e-mail to [email protected].
FOR FURTHER INFORMATION CONTACT: Tim A. Reed, Office of Nuclear Reactor
Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-
0001, telephone (301) 415-1462, e-mail [email protected].
SUPPLEMENTARY INFORMATION:
Background
The petition for rulemaking designated PRM-50-78 was received by
the NRC on September 9, 2002. A notice of receipt of the petition and
request for public comment was published in the Federal Register (FR)
on October 31, 2002 (67 FR 66347). The public comment period closed
January 16, 2003. Four letters of public comment were received in
response to the Federal Register notice.
The Petition
In PRM-50-78, the petitioner, Mr. Robert H. Leyse, requested that
regulations be developed to require addressing the impact of fouling on
the performance of all significant heat transfer surfaces in nuclear
power plants (NPPs). The requested rule changes would also require that
fouling impact be addressed in NRC-funded test programs and NRC-
produced computer codes that are used to assess cooling and heat
exchanger performance. The petitioner contended that fouling of heat
exchange surfaces is not adequately considered in the licensing and
compliance inspection of NPPs, for example, licensing bases and
technical specifications do not specifically limit fouling on fuel
elements. The petitioner also requested that regulations be added to
require publicly available performance reports on these surfaces,
including records of mechanical degradation, and cleaning procedures
and their effectiveness.
In addition, the petitioner contended that fouling would restrict
fuel element cooling and that axial growth beyond design limits would
cause fuel rods to bow, and contact other fuel rods and control rod
guide tubes. The petitioner claimed that this would lead to a safety
problem. In addition, the petitioner proposed that the rules should
require investigating grossly off-normal performance of heat exchange
equipment. For example, the petitioner stated that fouling of steam
generator tubes should be investigated because it has occasionally
reduced heat transfer effectiveness to force operation at below-normal
secondary side pressure, creating a safety issue.
Public Comments on the Petition
Four letters of public comment were received on PRM-50-78. Two were
from the petitioner, who noted in support of his petition that the
Advisory Committee on Reactor Safeguards (ACRS) did not address fouling
of heat exchange surfaces during a meeting with Electric Power Research
Institute (EPRI) in October 2002 and that one of the numerous heat
transfer tests done for the NRC by Westinghouse (FLECHT Run 9573)
resulted in tube failure. In addition, the petitioner noted that five
additional ACRS subcommittee meetings did not address fouling issues.
The Nuclear Energy Institute (NEI) opposed the petition, noting
that current reporting requirements in 10 CFR 50.72 and 50.73 require
reporting any event or condition that could interfere with a safety
function of any system needed to shutdown that plant and maintain it in
a safe condition, remove residual heat, control radiological material,
or mitigate accident consequences.
The Strategic Teaming and Resource Sharing (STARS) group, a
consortium of nuclear utilities, opposed the petition noting that these
same concerns were previously addressed by industry organizations in
comments on PRM-50-73, PRM-50-73A, and PRM-50-76. In the STARS group's
view, this latest petition restates the same concern in a different
context, without presenting any further evidence to provide a basis for
revising the regulations. The STARS group believes that the requested
additional reporting burden would not be justified by the unproven and
questionable scenarios presented in the petition.
NRC Technical Evaluation
The NRC reviewed each of the petitioner's requests and concluded
that none of the requests justified the initiation of rulemaking. The
NRC's responses to each of the petitioners' requests are as follows:
1. Regulations are needed to address the impact of fouling on the
performance of heat exchange surfaces throughout licensed nuclear power
plants. The petitioner stated that this included fuel elements, steam
generators, condensers, fan coolers, etc.
The NRC disagrees with the petitioner's assertion. The petitioner's
assertion that regulations are needed to address the impact of fouling
on fuel
[[Page 56959]]
elements was addressed previously in a Federal Register notice of
denial of PRM-50-73 and PRM-50-73A (also submitted by the petitioner)
published at 68 FR 41963 on July 16, 2003. The petitioner did not
submit any new information or provide any additional considerations
that would cause the NRC to reconsider the denial of PRM-50-73 and PRM-
50-73A.
In regard to other heat exchange surfaces, regulations and guidance
addressing fouling effects on heat exchanger performance already exist
for the primary and secondary sides of NPPs.
Specifically:
10 CFR 50.65 requires licensees to monitor performance
parameters or to demonstrate that monitoring is not needed, and to
provide preventive maintenance sufficient to ensure that all safety
related structures, systems, or components (e.g., heat exchangers
important to safety) are capable of fulfilling their intended
functions.
10 CFR part 50, Appendix A, Criterion 14 (or plant-
specific principal design criteria in the plant design basis for plants
issued construction permits before the effective date of 10 CFR part
50, Appendix A), requires that the reactor coolant pressure boundary
heat exchangers critical to safety (e.g., steam generators) be designed
and tested to ensure an extremely low probability of abnormal leakage
that might be caused by fouling or other factors. Steam generator tube
performance is closely monitored by inspection as detailed in plant
technical specifications. Technical specifications vary from plant to
plant, but each pressurized-water reactor (PWR) plant has requirements
to monitor steam generator tube performance.
10 CFR part 50, Appendix A, Criterion 44 (and equivalent
plant-specific criteria for pre-General Design Criteria (GDC) plants),
requires provision of a cooling system to transfer heat from
structures, systems, and components to an ultimate heat sink under
normal operating and accident conditions. This heat transfer function
is accomplished by structures and components (including heat
exchangers) in key safety systems such as the residual heat removal and
essential service water systems.
10 CFR part 50, Appendix A, Criteria 45 and 46 (and
equivalent plant-specific criteria for pre-GDC plants), require the
capability by design to perform inspection and testing of cooling water
systems to ensure integrity and adequate performance. The technical
specifications for each plant define limiting conditions for operation
(LCO) for systems that mitigate design basis transients and accidents.
The operability requirements for those systems defined in LCOs include
the adequate performance of heat exchangers needed for the systems to
perform their safety functions. The specific LCOs vary by plant type
and format of the plant-specific technical specifications. However,
each plant does have requirements related to safety-significant heat
removal systems such as residual heat removal and safety-related
service water. For a typical boiling water reactor, the LCOs include
but are not limited to LCOs 3.4.9 and 3.4.10 for residual heat removal,
LCO 3.5.1 for emergency core cooling, LCO 3.6.5.5 for drywell air
temperature, LCO 3.7.1 for standby service water and ultimate heat
sink, LCO 3.7.2 for high pressure core spray service water, and LCO
3.8.1 for diesel generators. Degradation of a heat exchanger that
renders a system covered by an LCO inoperable would require completion
of required actions, possibly including a shutdown of the affected
unit, within the required completion times. The administrative
requirements defined within all plants' technical specifications also
require licensees to establish and maintain various procedures related
to the operation and testing of plant requirement. A partial list of
the required procedures is provided in Regulatory Guide 1.33, ``Quality
Assurance Program Requirements (Operation).'' The NRC routinely
performs inspections of licensees' programs for implementing the
required procedures.
Generic Letter (GL) 89-13, ``Service Water System Problems
Affecting Safety-Related Equipment,'' July 18, 1989, recommended that
licensees initiate test programs to verify heat transfer capability of
all safety-related heat exchangers cooled by service water and routine
inspection and maintenance programs to ensure serviceability of safety-
related systems supplied by service water. Generic Letter 89-13
specifies that a continuing program for periodic retesting should
address the effects of fouling, and licensees monitor parameters such
as coolant flow, temperature, and pressure indicative of acceptable
heat exchanger performance.
The NRC oversees the licensees' testing and maintenance
programs via the inspection and assessment procedures included in the
reactor oversight process. The NRC inspection procedure IP 71111.07,
``Heat Sink Performance,'' defines the current sampling and review
process for NRC inspectors assessing licensees' programs for the
testing and maintenance of safety-significant heat exchangers.
Standard Review Plan (SRP) 4.2 describes the NRC review of
thermal margins, effects of corrosion products, and hydraulic loads.
This review also addresses postulated fuel failure resulting from
overheating of fuel cladding.
SRP 4.2 also describes the NRC review of licensee fuel
design analyses to ensure that dimensional changes due to thermal or
irradiation effects (such as fuel rod bowing or growth) are addressed.
Thus, the NRC believes that additional regulations are not needed
to address the impact of fouling on the performance of heat exchange
surfaces throughout licensed nuclear power plants.
2. Fouling of heat exchange surfaces in reactors has the potential
to cause significant safety problems.
The NRC acknowledges that, left undetected, excessive fouling of
key heat exchange surfaces, or other problems that challenge the safety
function of those heat exchangers, could represent a significant safety
problem. The classification of the important heat exchangers as safety-
related equipment, and the resultant requirements associated with their
design and maintenance, demonstrates their importance. The NRC
determined, for example, that the clogging of service water heat
exchangers could have caused safety significant problems in the past
and as a result issued several generic communications culminating in
Generic Letter 89-13, ``Service Water System Problems Affecting Safety-
Related Equipment,'' July 18, 1989. The NRC believes that the current
regulatory requirements for the testing and maintenance of heat
exchangers (as described in GL 89-13 along with recommendations for
meeting the requirements) are adequate to identify and correct
potential safety significant problems in safety-related heat
exchangers. Consequently, the NRC has determined that no new
regulations are required to address this issue. The NRC will continue
to monitor the implementation of GL 89-13 and will take appropriate
action if adverse trends are observed.
3. NRC regulations must require publicly available reporting on the
performance of heat exchange surfaces, including records of mechanical
degradation of heat transfer assemblies, and cleaning procedures and
their effectiveness.
The NRC believes that it is not necessary to report the routine
operational matters involving heat
[[Page 56960]]
exchanger degradation and cleaning which the petitioner proposes. The
NRC is interested in system performance degradation when the situation
might lead to a loss of safety function and regulations requiring such
reporting already exist. 10 CFR 50.72, ``Immediate notification
requirements for operating nuclear power reactors,'' and 10 CFR 50.73,
``Licensee event report system,'' require licensees to report on
performance of any safety system in the primary or secondary sides of
reactors if an event occurs that might compromise safe operating
conditions, such as a deviation from plant technical specifications
pertaining to residual heat removal systems.
Specifically, section 50.72(b)(3)(ii) requires reporting to the NRC
within eight hours any event or condition that results in: (1) the
condition of the nuclear power plant, including its principal safety
barriers, being seriously degraded, or (2) the nuclear power plant
being in an unanalyzed condition that significantly degrades plant
safety. In addition, section 50.72(b)(3)(v) requires eight hour
reporting of any event or condition that at the time of discovery could
have prevented fulfillment of the safety function of structures or
systems needed to: (1) Shutdown the reactor and maintain it in a safe
shutdown condition, (2) remove residual heat, (3) control the release
of radioactive material, and (4) mitigate the consequences of an
accident. Section 50.73 (a)(2)(i)(B) requires submittal of a Licensee
Event Report (LER) within sixty days regarding any operation or
condition prohibited by the plants' Technical Specifications, such as
failure of a covered heat exchanger, and 50.73(a)(2)(ii)(A) requires an
LER for any event or condition that resulted in the condition of the
nuclear power plant, including its principal safety barriers, being
seriously degraded. The NRC believes that existing reporting
requirements adequately address degradation of performance of heat
exchange surfaces in nuclear power plants.
4. NRC regulations must address the need for investigating the
grossly off-normal performance of heat exchange equipment in NPPs.
The NRC believes that the existing structure of regulations,
technical specifications, reporting requirements, and licensee programs
subject to NRC inspection provides the necessary confidence that plant
safety systems, including heat exchangers, are properly designed and
maintained. A discussion of the existing structure of requirements and
programs is provided in the NRC response to the petitioner's first
request. An additional regulatory requirement related directly to the
need for investigating the degradation of heat exchange equipment and
to take those actions necessary to ensure that the performance of the
equipment will support its safety function is provided by, Criterion
XVI, ``Corrective Action,'' of Appendix B to 10 CFR Part 50. This
regulation requires that conditions adverse to quality, such as a
significant degradation of a heat exchanger that is important to
safety, be promptly identified and corrected. The NRC ensures
compliance with these requirements by routinely performing inspections
of licensees' programs for identifying and correcting problems.
5. Severe fouling of nuclear fuel elements leads to axial growth of
the fuel rods beyond design limits as the operating temperature of the
fuel rods becomes greater than allowed for in design. This would cause
fuel rods to bow and contact adjacent rods and control rod guide tubes,
interfering with coolant flow.
The NRC believes that pressurized water reactor (PWR) and boiling
water reactor (BWR) fuel bundle designs provide ample space for fuel
pins to expand in the axial direction. A PWR fuel pin is neither
supported at the bottom nor at the top; instead, spacers are used to
hold the fuel pins together. Designed space both at the bottom and at
the top of fuel bundles permits fuel pins to expand thermally without
touching any other structures. A BWR fuel bundle is normally seated at
the bottom and there is no restriction to prevent thermal expansion
into the upper plenum. Expansion springs are sometimes used between
fuel pins to allow nonuniform axial expansion within a fuel bundle. For
these reasons, the NRC considers it unlikely that a fuel pin will bow
enough to contact adjacent rods and control rod tubes and interfere
with coolant flow. SRP 4.2 requires the NRC to review licensee fuel
design analysis to confirm that dimensional changes due to thermal or
irradiation effects such as fuel pin bowing or axial growth are
adequately addressed.
6. Fouling of heat-transfer surfaces is generally not adequately
considered in the licensing and compliance inspections of NPPs.
The NRC believes that the effects of fouling of heat transfer
surfaces are adequately addressed in the following NRC licensing and
compliance inspection program elements:
The NRC conducts an extensive review of the licensee's
design of key safety systems, structures, and components, including
heat exchangers in the primary and secondary sides of a plant. NRC
staff analyses of all key safety systems, including heat exchangers,
are performed during development of NRC safety evaluation reports
(SERs) pertaining to a license application. As previously discussed,
various regulatory requirements such as 10 CFR 50.65, Appendix B to
Part 50, and plant technical specifications require that licensees
maintain, test and restore equipment such that the safety functions are
maintained consistent with the licensing of the plant. These processes
are subject to NRC inspection to ensure that the requirements are met.
Inspections of safety systems, structures, and components,
including safety-significant heat exchangers, are designed to determine
compliance with Appendix A to Part 50, ``General Design Criteria for
Nuclear Power Plants.'' Specifically, in the Reactor Oversight Program,
Inspection Procedure 71111.07, ``Heat Sink Performance,'' requires that
a sample of safety significant heat exchangers (e.g., for the residual
heat removal, component cooling water, emergency core cooling systems)
be inspected both annually for specific performance issues and
biennially for an intense review of heat transfer characteristics.
7. The NRC must require by rule the inclusion of fouling
considerations in NRC-funded heat transfer test programs and in the
several heat exchanger computer programs produced by the NRC.
The NRC believes that these requirements do not need to be included
by regulation.
NRC-funded computer codes used to audit emergency core
cooling system (ECCS) performance are capable of considering the impact
of fouling on the performance of fuel element surfaces, and these codes
have been used for that purpose when warranted.
Ongoing experimental and analytical test programs (e.g.,
Argonne National Laboratory study on fuel cladding performance) in the
NRC Office of Nuclear Regulatory Research (RES) are investigating
transient and operational oxidation models, including effects of
significant pre-oxidation.
Calculations were performed by RES to support the
evaluation of this petition using NRC computer codes. These
calculations showed that fouling and excess pre-oxidation would not
have a significant effect on reflood heat transfer capability.
The NRC fuel performance code FRAPCON-3 can calculate
enhanced oxidation from crud buildup on fuel element surfaces.
[[Page 56961]]
The RELAP and TRACE codes use the FRAPCON information to
calculate transient effects.
The NRC has evaluated the advantages and disadvantages of the
rulemaking requested by the petitioner with respect to the five
performance goals set out by the Commission in the Strategic Plan for
Fiscal years 2004-2009 announced on August 12, 2004.
1. Maintaining Safety: The NRC believes that the requested
rulemaking would not make a significant contribution to maintaining
safety because current regulations, regulatory guidance and practices
already provide for monitoring, detecting, and correcting possible
fouling effects on heat exchanger performance. In addition, no data or
evidence was provided by the petitioner to suggest that fouling of heat
exchanger surfaces created any significant safety problems.
2. Ensure Secure Use and Management of Radioactive Material: The
petitioner has not established, nor has the NRC found the existence of,
any safety issues regarding the performance of heat exchange surfaces
that would compromise the secure use of licensed radioactive material.
3. Ensuring Openness in the NRC Regulatory Process: The
Administrative Procedures Act provides that any interested person has
the right to petition an agency for issuance, amendment, or repeal of a
rule. This statute expands on the ``right to petition'' provided by the
First Amendment to the Constitution. The NRC implements this statute
through 10 CFR 2.802, Petition for rulemaking, using guidance provided
in NUREG-BR-0053, Revision 5, U.S. NRC Regulations Handbook, to ensure
that the regulatory process takes place in an open manner.
4. Improving Efficiency, Effectiveness, and Realism: The proposed
revisions would not improve efficiency, effectiveness, and realism
because licensees and the NRC would be required to generate additional
and unnecessary information as part of the evaluation of numerous heat
exchanger surfaces throughout the nuclear power plant. Revising the
regulations to be more specific about effects of fouling on heat
exchanger performance would require an expenditure of NRC resources
with little or no added safety benefit.
5. Ensure Excellence in NRC Management: The petitioner's request to
revise the regulations to address the impact of fouling on all heat
exchange surfaces in a nuclear power plant is not applicable to the
strategic goal of continuous improvement in NRC management
effectiveness.
Reasons for Denial
The Commission is denying the petition for rulemaking (PRM-50-78).
The NRC regulation and oversight of nuclear power plants includes
the establishment of regulations, the issuance of operating licenses
and technical specifications, and continual inspections and technical
reviews of licensee programs and plant performance. When viewed in
total, these regulatory requirements and related oversight practices
provide confidence in the safety of operating nuclear power plants. The
NRC's finding that no rulemaking is required, is based on the
determination that the existing structure of regulations (i.e., 10 CFR
50.65, Appendix A and B to part 50), technical specifications, and
licensee programs subject to NRC inspection provides confidence that
plant safety features, including heat exchangers, are properly designed
and maintained in order to fulfill their intended function.
The Commission concludes that the integration of the various
requirements and related NRC oversight functions provide reasonable
assurance that systems important to safety, such as heat exchangers,
will perform their intended functions. The addition of specific
requirements to a regulation to address heat exchanger performance is
not necessary.
For these reasons, the Commission denies PRM-50-78.
Dated in Rockville, Maryland, this 17th day of September, 2004.
For the Nuclear Regulatory Commission.
Annette L. Vietti-Cook,
Secretary of the Commission.
[FR Doc. 04-21337 Filed 9-22-04; 8:45 am]
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