Information Notice 2019-01, Inadequate Evaluation of Temporary Alterations
| ML18115A338 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom, Salem, Watts Bar, Sequoyah  |
| Issue date: | 03/12/2019 |
| From: | Alfred Issa NRC/NRR/DIRS/IOEB, NRC/NRR/DIRS/IRGB |
| To: | |
| Benney B | |
| References | |
| IN-19-001 | |
| Download: ML18115A338 (5) | |
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
OFFICE OF NEW REACTORS
WASHINGTON, DC 20555-0001 March 12, 2019 NRC INFORMATION NOTICE 2019-01: INADEQUATE EVALUATION OF TEMPORARY
ALTERATIONS
ADDRESSEES
All holders of an operating license or construction permit for a nuclear power reactor under
Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of
Production and Utilization Facilities, except those that have permanently ceased operations
and have certified that fuel has been permanently removed from the reactor vessel.
All holders of and applicants for a combined license under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
PURPOSE
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert
licensees about recent operating experience at nuclear power facilities where temporary
alterations were installed that either negatively impacted the operability of affected Systems, Structures, and Components or without performing required 10 CFR 50.59 reviews.
The NRC expects that recipients will review the information contained in this IN for applicability
to their facilities and consider actions, as appropriate, to avoid similar issues. INs may not
impose new requirements, and nothing in this IN should be interpreted to require specific action.
DESCRIPTION OF CIRCUMSTANCES
Sequoyah, Units 1 and 2
On November 24, 2018, the licensee for Sequoyah, Units 1 and 2, discovered that a door was
blocked open to allow a hose to be routed from an outside vacuum truck to an ice bin inside the
Unit 2 Additional Equipment Building without meeting the compensatory measures required by
the related breach permit. This condition created a breach of the auxiliary building secondary
containment enclosure (ABSCE) boundary that exceeded the allowed ABSCE breach margin of
three minutes. As a result, Unit 1 entered Technical Specification (TS) Limiting Condition of
Operation 3.7.12, Condition B for two trains of Auxiliary Building Gas Treatment System
(ABGTS) inoperable due to an inoperable ABSCE boundary in MODE 1, 2, 3, or 4, and both
Units entered Condition E for one required ABGTS train inoperable with fuel stored in the spent
fuel pool. The event was caused by a failure to cover in the pre-job brief the ABSCE breach
permit, required compensatory measures and internal and external operating experience.
Corrective actions included closing the door and revising the associated work order to add a
hold point to ensure the ABSCE permit is reviewed, understood, and adhered to prior to and
during the breach. See Licensee Event Report 2018-002-00, Exceeded Breach Margin
Renders Both Trains of the Auxiliary Building Gas Treatment System Inoperable dated January
ML18115A338 22, 2019, (Agencywide Documents Access and Management System (ADAMS) No.
ML19022A040) for more details.
Sequoyah, Units 1 and 2
On March 3, 2017, Door A212 was improperly breached at the Sequoyah nuclear power plant to
facilitate a continuous fire watch. Although a fire protection impairment permit was generated, the permit did not evaluate the impact of the breach on the ABSCE boundary. On March 7,
2017, a senior reactor operator discovered the breach during a walk down of the Auxiliary
Building. The breach resulted in the inoperability of two trains of the ABGTS due to an
inoperable ABSCE boundary. An evaluation determined the cause to be a less than adequate
single barrier breaching standard. A contributing cause was an inconsistent approach to entry
into the barrier breaching process. In addition to restoring operability by closing the door, corrective actions included revising the breaching procedure to address all possible breaches
and to include a matrix for doors and their associated impacts. See Licensee Event Report
2017-001-00 Breached Door Renders Both Trains of the Auxiliary Building Gas Treatment
System Inoperable dated April 26, 2017, (ADAMS No. ML17117A495) for more details.
Salem, Unit 2
On August 26, 2015 and again on or about September 10, 2015, NRC inspectors conducting
walkdowns at the Salem, Unit 2 while in Mode 1, noted that the boric acid evaporator rooms
interior wall had been removed while two watertight doors were fully open. Given Salem TS 3.7.7 requires that auxiliary building differential pressure be slightly negative in Mode 1, the
inspectors made the control room aware of concerns regarding operability of the auxiliary
building differential pressure as well as the impairment of the barrier. The licensee closed the
outer watertight doors and subsequently, confirmed the doors classification as high energy line
break (HELB) and flooding doors. The impairment required a plant barrier impairment (PBI)
which had not been previously completed. In addition, the licensee determined that removing
the interior wall made the evaporator room part of the auxiliary building contiguous zone
envelope. The licensees investigation and causal evaluation determined that technicians had
breached the metal panel that formed the interior wall of the evaporator room on or around
November 11, 2014, and that the outer doors had been opened on numerous occasions from
that time through September 2015. The licensee determined that one apparent cause was
inadequate procedural guidance that resulted in work planners not requesting a PBI, personnel
not meeting the intent of the attendant requirement, and departments not requiring proof that the
Technical Specifications would be met prior to opening the doors. Corrective actions included
properly implementing barrier controls that included compensatory actions for the flooding and
occupational radiation barrier aspects of the program.
As a result, the NRC inspectors issued a non-cited violation for the improper implementation of
barrier controls while performing maintenance that could affect the performance of the auxiliary
building envelope. NRC Inspection Report 05000272/2015004 and 05000311/2015004, dated
February 10, 2016 (ADAMS No. ML16043A169), provides more details about this finding.
Salem, Units 1 and 2
On October 3, 2013, an NRC Resident Inspector observed that the Turbine Driven Auxiliary
Feedwater (TDAFW) pump room enclosure HELB barrier door was being held open for an
extended period by an assigned door attendant. The Motor Driven Auxiliary Feedwater
(MDAFW) pumps are located adjacent to the enclosure such that if a secondary steam HELB
event were to occur in the TDAFW pump room while its door was open or disabled, the steam
ML18115A338 plume from the room could render both MDAFW pumps inoperable. The cause of this event is
attributed to an organizational failure to ensure that guidance provided in plant HELB program
procedures contained sufficient justification for compensatory actions used for barrier
impairments. Corrective actions taken by the licensee included: a plant-wide communication
was made describing the HELB event and its impact on operability of plant equipment; a
revision to the Operability Assessment and Equipment Control Program procedure was made to
ensure it conforms to the guidance of NRC Regulatory Issue Summary 2001-09, Control of
Hazard Barriers; and permanent signs were installed on all HELB barrier doors prohibiting them
from being blocked open without authorization from Salem Operations. See Licensee Event
Report 2014-001-00, High Energy Line Break Door Blocked Open During Maintenance Activity
dated March 10, 2014 (ADAMS No. ML14069A245), for more details.
Watts Bar, Unit 1
On July 9, 2012, inspectors from the NRC identified a finding related to a failure to correctly
translate the design basis related to onsite flooding into the instructions for a plant design
change temporary alteration. Specifically, a procedure provided a means to erect a temporary, water-tight flood barrier around both trains of the Thermal Barrier Booster Pumps (TBBP). This
barrier was designed to be sealed with a sealant that would not prevent water intrusion as
required. Additional design issues were identified by the inspectors on July 14, 2012, that
included: (1) the lack of adequate preparation/cleaning of surfaces as recommended by the
sealant manufacturer prior to applying the sealant; (2) failure to perform load calculations for
panel deformation; and (3) failure to include provisions in the design and installation to support
the temporary panels to resist deflection from hydrostatic pressure/force and potential uplift
forces, since the panels were not anchored to the floor. As a result, the TBBP flood barrier
would have failed during a probable maximum flood event, thereby submerging the TBBPs and
rendering the equipment inoperable. Corrective actions included the removal of the installed
panel assembly and its replacement. The replacement activity included the preparation/
cleaning of surfaces to be sealed and the use of an approved sealant primer, as recommended
by the sealant manufacturer, prior to applying the sealant. A vertical brace was also installed to
resist potential uplift forces. NRC Inspection Report 05000390/2012009, dated March 12, 2013 (ADAMS No. ML13071A289), provides more details about this finding.
Peach Bottom, Unit 3
Between January 21, 2009 and September 9, 2009, the licensee for Peach Bottom, Unit 3 declared the E Wide Range Neutron Monitor (WRNM) inoperable and installed a jumper that
bypassed its trip feature instead of using the WRNM bypass switch as is described in their
plant's Final Safety Analysis Report. Since only 3 of 4 WRNMs were required by Technical
Specifications, no action statement was entered and installing the jumper was thought to be
acceptable. However, installing the jumper was done without performing a 10 CFR 50.59 review. This installation involved a facility change that likely would have required a license
amendment before its implementation. Corrective actions included entering the issue into the
licensees Corrective Action Program and the removal of the jumper restoring the system to its
configuration. For more details, see NRC Inspection Report 05000277/2009004 and
05000278/2009004, Peach Bottom Atomic Power Station - NRC Integrated Inspection Report
dated November 12, 2009 (ADAMS No. ML093160608).
DISCUSSION
The above events highlight the need to adequately establish and implement procedural controls
for temporary alterations to insure their compliance with the requirements of all NRC regulations
ML18115A338 such as 10 CFR 50.59, Changes, tests and experiments and 10 CFR 50.65, Requirements for
monitoring the effectiveness of maintenance at nuclear power plants. The first five events
resulted in equipment inoperability while the sixth event resulted in a violation of 10 CFR 50.59 requirements.
NRC Regulatory Guide 1.187, Guidance for Implementation of 10 CFR 50.59, Changes, Tests, and Experiments, endorses the Nuclear Energy Institute (NEI) document NEI 96-07, Guidelines for 10 CFR 50.59 Evaluations, Revision 1 ADAMS No. ML003771157). Temporary
alterations include jumpering terminals, lifting leads, placing temporary lead shielding on pipes
and equipment, removal of barriers, and use of temporary blocks, bypasses, scaffolding and
supports. Although the requirements of 10 CFR 50.59 do not generally apply to temporary
alterations, there are some exceptions that are listed in NEI 96-07. Exceptions include
compensatory actions to address degraded or nonconforming conditions, and temporary
alterations expected to be in effect during at-power operations for more than 90 days. In
addition, regardless of whether the requirements of 10 CFR 50.59 apply, Section 4.1.2, Maintenance Activities of NEI 96-07, requires licensees to ensure equipment operability in
accordance with the technical specifications is maintained as a result of maintenance activities
and to assess and manage their risk impact per 10 CFR 50.65(a)(4). Note that maintenance
activities include temporary alterations.
Related NRC Generic Communications
The NRC has previously issued the following two related generic communications:
Information Notice 2007-29, Temporary Scaffolding Affects Operability of Safety-Related
Equipment, dated September 17, 2007, describes similar issues to the ones discussed in this
IN as they relate to scaffolding. Events discussed include scaffolding that: interferes with the
operation of equipment, blocks access to fire protection equipment, is improperly braced to
prevent sliding during use or during a seismic event, or is attached to instrument racks or piping
supports without adequate justification.
Regulatory Issue Summary 2001-09, Control of Hazard Barriers, dated April 2, 2001, clarifies
the NRC position on the temporary removal of hazard barriers.
CONTACT
S
Please direct any questions about this matter to the technical contact listed below.
Christopher G. Miller, Director Timothy J. McGinty, Director
Division of Inspection and Regional Division of Construction Inspection and
Support Operational Programs
Office of Nuclear Reactor Regulation Office of New Reactors
Technical Contacts: Alfred Issa, NRR Brian Benney, NRR
301-415-5342 301-415-2767 E-mail: Alfred.Issa@nrc.gov Email: Brian.Benney@nrc.gov
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, under NRC Library.
ML18115A338 OFFICE NRR/DIRS/IOEB QTE RES/DE/RGGIB NRO/DCIP/CIPB
NAME AIssa JDougherty TBoyce VHall
DATE 2/26/2019 9/26/2018 9/28/2018 2/13/19 OFFICE NRR/DIRS/IOEB NRR/DIRS/IRGB NRR/DIRS/IRGB NRO/DCIP
NAME RElliott BBenney TInverso TMcGinty
DATE 2/4/2019 2/26/2019 2/26/2019 02/27/2019 OFFICE NRR/DIRS
CMiller
NAME
/RA by B. Dickson for/
DATE 03/12/2019