ML22139A309
| ML22139A309 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 05/19/2022 |
| From: | Jorge Corujo-Sandin NRC/RGN-III/DRS/EB2 |
| To: | Domingos C Northern States Power Co |
| References | |
| IR 2022003 | |
| Download: ML22139A309 (11) | |
See also: IR 05000263/2022003
Text
May 19, 2022
Mr. Christopher Domingos
Site Vice President
Monticello Nuclear Generating Plant
Northern States Power Company, Minnesota
2807 West County Road 75
Monticello, MN 55362-9637
SUBJECT: MONTICELLO NUCLEAR GENERATING PLANT - REQUEST FOR
INFORMATION FOR AN NRC TRIENNIAL HEAT EXCHANGER/SINK
PERFORMANCE INSPECTION AND REQUEST FOR INFORMATION;
INSPECTION REPORT 05000263/2022003
Dear Mr. Domingos:
On August 22, 2022, the U.S. Nuclear Regulatory Commission (NRC) will begin the onsite
portion of the Triennial Heat Exchanger/Sink Performance Inspection at Monticello Nuclear
Generating Plant. This inspection will be performed in accordance with NRC baseline
Inspection Procedure 71111.07.
The Triennial Heat Exchanger/Sink Performance Inspection focuses on service water cooled
heat exchangers, closed loop heat exchangers and the ultimate heat sink (UHS). The
inspection verifies that the selected service water cooled heat exchanger(s), closed loop heat
exchanger(s) and the UHS remain capable of performing their intended safety functions.
The inspection includes 1 week onsite. The inspection team will consist of two NRC inspectors.
The current inspection schedule is as follows:
Preparation week: August 15-19, 2022
Onsite week: August 22-26, 2022
In order to minimize the impact that the inspection has on the site and to ensure a productive
inspection, a request for documents needed for the inspection is enclosed. The information
request has been divided into three groups:
The first group lists information necessary for the initial inspection scoping activities.
This information should be available to the lead inspector no later than June 27,
2022. The lead inspector will communicate the initial selected set of approximately
2-3 risk significant heat exchangers by July 11, 2022.
The second group is needed to support the in-office preparation activities. This set
of documents, including the calculations associated with the selected heat
exchangers, should be available at the Regional Office no later than August 01,
2022. This information should be separated for each selected component, especially
if provided electronically (e.g., folder with component name that includes
C. Domingos -2-
calculations, condition reports, maintenance history, etc.). During the in-office
preparation activities, the inspector may identify additional information needed to
support the inspection.
The last group includes the additional information above as well as plant specific
reference material. This information should be available to the inspector on
August 15, 2022. It is also requested that corrective action documents and/or
questions developed during the inspection be provided to the inspector as the
documents are generated.
All requested documents are to be for the time period from the onsite inspection period back to
the documents that were provided in response to the previous heat sink performance
inspection. If no activities were accomplished in that time period, then the request applies to the
last applicable document in the previous time period. It is important that these documents be as
complete as possible, in order to minimize the number of documents requested during the
preparation week or during the onsite inspection.
The lead inspector for this inspection is Jorge Corujo-Sandin. We understand that our licensing
contact for this inspection is Carrie Seipp of your organization. If there are any questions about
the inspection or the material requested in the enclosure, please contact the lead inspector at
630-829-9741 or via e-mail at jorge.corujo-sandin@nrc.gov.
This letter does not contain new or amended information collection requirements subject to the
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Existing information collection
requirements were approved by the Office of Management and Budget, Control
Number 3150-0011. The NRC may not conduct or sponsor, and a person is not required to
respond to, a request for information or an information collection requirement unless the
requesting document displays a currently valid Office of Management and Budget Control
Number.
C. Domingos -3-
In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 2.390, Public
Inspections, Exemptions, Requests for Withholding, of the NRC's "Rules of Practice," a copy of
this letter and its enclosure will be available electronically for public inspection in the NRC Public
Document Room or from the Publicly Available Records (PARS) component of NRCs
Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible
from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic
Reading Room).
Sincerely,
Signed by Corujo-Sandin, Jorge
on 05/19/22
Jorge Corujo-Sandin, Senior Reactor Inspector
Engineering Branch 2
Division of Reactor Safety
Docket No. 50-263
License No. DPR-22
Enclosure:
Triennial Heat Sink Performance Inspection
Document Request
cc: Distribution via LISTSERV
C. Domingos -4-
Letter to Christopher Domingos from Jorge Corujo-Sandin dated May 19, 2022.
SUBJECT: MONTICELLO NUCLEAR GENERATING PLANT - REQUEST FOR
INFORMATION FOR AN NRC TRIENNIAL HEAT EXCHANGER/SINK
PERFORMANCE INSPECTION AND REQUEST FOR INFORMATION;
INSPECTION REPORT 05000263/2022003
DISTRIBUTION:
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ADAMS Accession Number: ML22139A309
Publicly Available Non-Publicly Available Sensitive Non-Sensitive
OFFICE RIII
NAME JCorujo-Sandin:mb
DATE 05/19/2022
OFFICIAL RECORD COPY
TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
HEAT EXCHANGER/SINK PERFORMANCE
REQUEST FOR INFORMATION
I. ADMINISTRATIVE INSPECTION INFORMATION
Inspection Report Number: 05000263/2022003
Onsite Inspection Dates: August 22-26, 2022
Inspection Procedure: IP 71111.07, HEAT EXCHANGER/SINK PERFORMANCE
Jorge Corujo-Sandin, Senior Reactor Inspector, DRS
Lead Inspector: 630-829-9741
jorge.corujo-sandin@nrc.gov
Teammates: Daneira Meléndez-Colón, Reactor Inspector, RIII/DRS
I. Information Requested by: June 27, 2022
1. List of the Generic Letter (GL) 89-13, Service Water System Problems Affecting
Safety-Related Equipment, heat exchangers in order of risk significance.
a. Identify if the heat exchanger is service water cooled or a closed loop heat
exchanger.
2. Copy of heat exchanger performance trending data tracked for each GL 89-13 heat
exchanger.
3. List of corrective action program documents (with a short description) associated
with GL 89-13 heat exchangers, heat sinks, silting, corrosion, fouling, or heat
exchanger testing, for the previous 3 years or since the last corrective action
program document list was sent to the NRC for the previous heat sink performance
inspection. The list should include all corrective action program documents not on
the last corrective action program document list.
4. Copy of any self-assessment done on any of GL 89-13 heat exchangers.
5. Last two System Health Report(s) and maintenance rule system notebooks for all the
GL 89-13 heat exchangers.
6. List of engineering-related operator workarounds (with a short description)
associated with GL 89-13 heat exchangers. The requested documents are to be for
the time period from the onsite inspection period back to the documents that were
provided in response to the previous heat sink performance inspection.
Enclosure
TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
7. List of permanent and temporary modifications (with a short description) associated
with GL 89-13 heat exchangers. The requested documents are to be for the time
period from the onsite inspection period back to the documents that were provided in
response to the previous heat sink performance inspection.
8. Provide a list of all corrective action documents, with a short description, associated
with the UHS for the previous three years or since the last corrective action program
document list was sent to the NRC for the previous Triennial heat sink performance
inspection.
II. Information Requested by: August 01, 2022
1. Copies of the GL 89-13 responses.
2. Copy of the Updated Final Safety Analysis Report (UFSAR) section applicable to the
GL 89-13 Heat Exchanger Program.
3. Copies of procedures developed to implement the recommendations of GL 89-13
(e.g., the GL 89-13 Heat Exchanger Program description).
4. Copies of the selected corrective action program documents.
5. For the specific heat exchangers selected:
a. Copies of the UFSAR sections applicable for each heat exchanger.
b. Copy of system description and design basis document for the heat exchangers
(as applicable).
c. Provide a list of calculations (with a short description) which currently apply to
each heat exchanger.
i. Establish the limiting design basis heat load required to be removed by
each of these heat exchangers;
ii. Demonstrate the heat exchangers capacity to remove the limiting heat
load;
iii. Correlate surveillance testing and/or inspection results from these heat
exchangers with design basis heat removal capability (e.g., basis for
surveillance test and/or inspection acceptance criteria);
iv. Evaluate the potential for water hammer in each heat exchanger or
associated piping; and
v. Evaluate excessive tube vibration in each heat exchanger.
d. Copy of any operability determinations or other documentation of degradation
associated with the heat exchangers or the systems that support the operation
for the selected heat exchangers.
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TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
e. Copy of the construction code, Design Specification, heat exchanger data
sheets, and vendor documents including component drawings applicable for the
heat exchangers.
f. Copies of normal, abnormal, and emergency operating procedures associated
with the selected heat exchangers.
6. For the ultimate heat sink (UHS):
a. Copies of the applicable UFSAR sections.
b. Copy of system description and design basis document (as applicable).
c. Copy of any operability determinations or other documentation of degradation
associated with the UHS.
d. Copy of the document (e.g., UFSAR, Technical Requirements Manual or
procedure) that states the maximum cooling water system inlet temperature limit
that still allows full licensed power operation of the nuclear reactor.
e. Copy of system description and design basis document (as applicable).
f. Copy of the construction code and Design Specification.
g. Copies of normal, abnormal, and emergency operating procedures associated
with the UHS including procedures for loss of this systems.
h. Provide a list of calculations (with a short description), which currently apply to
UHS.
i. Provide a list of instruments (with a short description) associated with automatic
or alarm functions for the UHS.
j. Provide a list of any design change (with a short description) performed on the
UHS since the last heat sink performance inspection.
7. A schedule of all inspections, cleanings, maintenance, or testing of any
safety-related plant heat exchanger to be performed during the on-site portion of the
inspection.
III. Information Requested to be Available for Inspection Preparation by: August 15, 2022
1. For the specific service water cooled heat exchangers selected:
a. Copy of the calculation which correlates surveillance testing results from these
heat exchangers with design basis heat removal capability (e.g., basis for
surveillance test acceptance criteria).
b. Copies of the two most recent completed tests and evaluation data confirming
thermal performance for those heat exchangers which are performance tested.
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TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
c. Documentation and procedures that identify the types, accuracy, and location of
any special instrumentation used for the two most recently completed thermal
performance tests for the heat exchangers (e.g., high accuracy ultrasonic flow
instruments or temperature instruments). Include calibration records for the
instruments used during these tests.
d. Information regarding any alarms which monitor on-line performance.
e. Copy of the document describing the inspection results of each heat exchanger.
The requested documents are to be for the time period from the onsite inspection
period back to the documents that were provided in response to the previous
heat sink performance inspection.
f. The cleaning and inspection maintenance schedule for each heat exchanger for
the next 5 years.
g. Copy of the design specification and heat exchanger data sheets for each heat
exchanger.
h. Copy of the vendor manuals including component drawings for each heat
exchanger.
i. Copy of the calculation which establishes the limiting (maximum) design basis
heat load which is required to be removed by each of these heat exchangers.
j. Copy of the operating procedures that ensure that the maximum cooling water
system inlet temperature limit is not exceeded.
k. Copy of the calculations or documents which evaluate the potential for water
hammer in each heat exchanger or associated piping.
l. Copy of the calculations that evaluate excessive tube vibration in each heat
exchanger and the documents that describe the controls that prevent heat
exchanger degradation due to excessive flow induced vibration during operation.
m. Copy of the periodic flow testing at or near maximum design flow. The requested
documents are to be for the time period from the onsite inspection period back to
the documents that were provided in response to the previous heat sink
performance inspection.
n. Copy of the document which identifies the current number of tubes in service for
each heat exchanger and the supporting calculation which establishes the
maximum number of tubes which can be plugged in each heat exchanger.
o. Copy of the document establishing the repair criteria (plugging limit) for degraded
tubes which are identified in each heat exchanger.
p. Copies of the documents that verify the structural integrity of the heat exchanger
(e.g., eddy current summary sheets, ultrasonic testing results, and visual
inspection results).
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TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
2. For the specific closed loop heat exchangers selected:
a. Copy of the design specification and heat exchanger data sheets for each heat
exchanger.
b. Copy of the vendor manuals including component drawings for each heat
exchanger.
c. Copy of the calculation which establishes the limiting (maximum) design basis
heat load which is required to be removed by each of these heat exchangers.
d. Copy of the operating procedures that ensure that the maximum cooling water
system inlet temperature limit is not exceeded.
e. Copy of the calculations or documents which evaluate the potential for water
hammer in each heat exchanger or associated piping.
f. Copy of the calculations that evaluate excessive tube vibration in each heat
exchanger and the documents that describe the controls that prevent heat
exchanger degradation due to excessive flow induced vibration during operation.
g. Copy of the periodic flow testing at or near maximum design flow. The requested
documents are to be for the time period from the onsite inspection period back to
the documents that were provided in response to the previous heat sink
performance inspection.
h. Copy of the document which identifies the current number of tubes in service for
each heat exchanger and the supporting calculation which establishes the
maximum number of tubes which can be plugged in each heat exchanger.
i. Copy of the document establishing the repair criteria (plugging limit) for degraded
tubes which are identified in each heat exchanger.
j. Copies of the documents that verify the structural integrity of the heat exchanger
(e.g., eddy current summary sheets, ultrasonic testing results, and visual
inspection results).
k. Copies of those documents that describe the methods taken to control water
chemistry in the heat exchangers.
3. For the review of the operation of the UHS:
For review of the operation of the service water system and UHS:
a. Copies of any design change performed on the UHS. The requested documents
are to be for the time period from the onsite inspection period back to the
documents that were provided in response to the previous heat sink performance
inspection.
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TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
b. Copies of any design change performed on the safety-related service water
system. The requested documents are to be for the time period from the onsite
inspection period back to the documents that were provided in response to the
previous heat sink performance inspection.
c. Copies of procedures for a loss of UHS. Provide documentation that the
instrumentation, which is relied on for decision-making is available and
functional.
d. Copies of procedures for a loss of service water system.
e. Inspections and/or maintenance related to preventing macrofouling (e.g., silt,
dead mussel shells, or debris) and biotic fouling (e.g., fish, algae, grass, or kelp).
The requested documents are to be for the time period from the onsite inspection
period back to the documents that were provided in response to the previous
heat sink performance inspection.
f. Copies of chemistry procedures that monitor for pH, calcium hardness, etc.
Also, provide copies of the associated results. The requested documents are to
be for the time period from the onsite inspection period back to the documents
that were provided in response to the previous heat sink performance inspection.
g. Copies of documents associated with the monitoring of pump performance for
potential strong-pump vs. weak-pump interaction.
For the review of the performance testing of the safety-related service water system
(or equivalent) and the UHS:
h. Copies of the last two performance tests, such as the American Society of
Mechanical Engineers in-service test, for the pumps, valves, and, if applicable,
the towers fans in the safety-related service water system. If the components are
not performance tested, please provide documentation verifying performance by
the methods actually used.
i. Copies of the documents that demonstrate that flow balance testing was
performed during the last 3 years. If the last flow test was performed longer than
3 years, then provide the last flow test.
j. Copies of the documents that demonstrate that flow balance testing will continue
to be periodically done in the future.
k. Copies of procedures used to monitor interface valves between the safety related
section of the service water system and the non-safety related section and the
associated results. The requested documents are to be for the time period from
the onsite inspection period back to the documents that were provided in
response to the previous heat sink performance inspection.
l. Copies of the procedures that verify the performance of risk significant non-safety
functions and the associated results. The requested documents are to be for the
time period from the onsite inspection period back to the documents that were
provided in response to the previous heat sink performance inspection.
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TRIENNIAL HEAT EXCHANGER/SINK PERFORMANCE DOCUMENT REQUEST
4. For review of the UHS Containment Device or Dam:
a. Copies of the toe of the weir or embankment inspection procedures and the
associated results. The requested documents are to be for the time period from
the onsite inspection period back to the documents that were provided in
response to the previous heat sink performance inspection.
b. Copies of the inspection procedures of the rip rap protection placed on excavated
side slopes and the associated results. The requested documents are to be for
the time period from the onsite inspection period back to the documents that
were provided in response to the previous heat sink performance inspection.
c. Copies of the dam inspection procedures that monitor the integrity of the heat
sink and the associated results. The requested documents are to be for the time
period from the onsite inspection period back to the documents that were
provided in response to the previous heat sink performance inspection.
d. Copies of calculations and surveillances that determine the UHS reservoir
capacity and heat transfer capability.
e. Copies of surveillance procedures and testing results performed on the
instrumentation relied upon to determine UHS reservoir capability. The
requested documents are to be for the time period from the onsite inspection
period back to the documents that were provided in response to the previous
heat sink performance inspection.
f. Copies of the inspection procedures for the verification of the structural integrity
of underwater UHS and the associated results. The requested documents are to
be for the time period from the onsite inspection period back to the documents
that were provided in response to the previous heat sink performance inspection.
g. Copies of the maintenance and/or inspection procedures for underwater UHS
sediment intrusion and the associated results including underwater diving
inspections and/or sediment removal activities. The requested documents are to
be for the time period from the onsite inspection period back to the documents
that were provided in response to the previous heat sink performance inspection.
h. Copies of calculations and surveillances that determine the UHS reservoir
capacity and heat transfer capability.
i. Copies of surveillance procedures and testing results performed on the
instrumentation relied upon to determine UHS reservoir capability. The
requested documents are to be for the time period from the onsite inspection
period back to the documents that were provided in response to the previous
heat sink performance inspection.
If the information requested above is not be available, please contact Jorge Corujo-Sandin as
soon as possible at 630-829-9741 or via e-mail at jorge.corujo-sandin@nrc.gov.
7