ML20195J599
| ML20195J599 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/19/1998 |
| From: | Cruse C BALTIMORE GAS & ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9811250026 | |
| Download: ML20195J599 (23) | |
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CHAnus H.C u:E Baltimore Gas and Electric Company Vice President Calvert Cliffs Nuclear Power Plant Nuclear Energy 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 410 495-4455 November 19,1998 l
i U. S. Nuclear Regulatory Commission i
Washington, DC 20555 ATTENTION:
Document Control Des'k
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2; Docket Nos. 50-317 & 50-318 Response to Request for Additional Information for the Review of the Calvert Cliffs Nuclear Power Plant, Units 1 & 2, Integrated Plant Assessment Reports j
for Component Supports and Piping Segments that Provide Structural Support, and Errata
REFERENCES:
(a)
Letter from Mr. C. II. Cruse (DGE) to NRC Document Control Desk, dated October 22,1997, " Request for Review and Approval of System and Commodity Reports for License Renewal" (b)
Letter from Mr. C.11. Cruse (BGE) to NRC Document Control Desk, dated March '27 1998, " Request for Review and Approval of Commodity and System Reports and the Time-Limited Aging Analyses for License Renewal" (c)
Letter from Mr. D. L. Solorio (NRC) to Mr. C. H. Cruse (BGE),
j September 7,1998," Request for Additional Information for the Review i
of the Calvert Cliffs Nuclear Power Plant, Unit Nos.1 & 2, Commodity Reports for Component Supports and Piping Segments that Provide Structural Support" (d)
Letter from Mr. D. L. Solorio (NRC) to Mr. C. H. Crr.se (BGE),
September 24,1998, " Renumbering of NRC Requests for Additional
, Y,>Q s
Information on Calvert Cliffs Nuclear Power Plant License Renewal )
Q' Application Submitted by the Baltimore Gas and Electric Company" References (a) and (b) forwarded Baltimore Gas and Electric Company (BGE) system and commodity reports, plus the Time-Limited Aging Analyses, for license renewal. Reference (c) forwarded questions from NRC staff on two of those reports, the Integrated Plant Assessment Report on the Component Supports and the Integrated Plant Assessment Report on Piping Segments that Provide Structural Support. Reference (d) forwaided a numbering system for tracking BGE's response to all of the BGE License Renewal Application requests for additional information and the resolution of the responses.
~ Attachment (1) provides our responses to the questions contained in Reference (c). The questions are 9811250026 981119 PDR ADOCK 05000317-NRC Distribution Code A036D P
-1 1
Documtnt Control Desk Nov:;mber 19,1998 Page 2 renumbered in accordance with Reference (d).
Attachment (2) provides errata to Section 3.1, Component Supports, of the BGE LRA.
Should you have further questions regarding this matter, we will be pleased to discuss them with you.
Very truly yours,
/
STATE OF MARYLAND
- TO WIT:
COUNTY OF CALVERT 1, Charles H. Cruse, being duly sworn, state that I am Vice President, Nuclear Energy Division, Baltimore Gas and Electric Company (BGE), and that I am duly authorized to execute and file this response on behalf of BGE. To the best of my knowledge and belief, the statements contained in this document are true and correct. To the extent that these statements are not Sased on my personal knowledge, they are based upon information provided by other BGE employees and/or consultants. Such information has been reviewed in accordance with company practice and I believe it to be reliable.
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Subscribed and sworn before me, a Notary Public in and for the State of Maryland and County of OA./w.68'
. this /9 dayof, M,1998.
' WITNESS my Hand and Notarial Seal:
N Notary Public My Commission Expires:
! SOOM t$te '
CHC/KRE/ dim Attachments: (1) Response to Request for Additional Information; Integrated Plant Assessment Reports for the Component Supports and Piping Segments that Provide Structural Support (2) Errata to Section 3.1, Component Supports; License Renewal Application ec:
' R. S. Fleishman, Esquire C. I. Grimes, NRC J. E. Silberg, Esquire D. L. Solorio, NRC S. S. Bajwa, NRC Resident inspector, NRC A. W. Dromerick, NRC R. I. McLean, DNR.
H. J. Miller, NRC J. H. Walter, PSC
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ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORT COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE STRUCTURAL SUPPORT 1
Baltimore Gas and Electric Company Calvert Cliffs Nuclear Power Plant November 19,1998
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1 ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR Tile COMPONENT SUPPORTS AND PIPING SEGMENTS TilAT PROVIDE STRUCTURAL SUPPORT a
NRC Ouestion No. 3.1.1 Table 3.1-1 contains a list of systems within the scope of license renewal that contain component supports within the commodity evaluation cover under Section 3.1, " Components Supports," of the Baltimore Gas and Electric Company (BGE) License Renewal Application (LRA). This list was compared to the list of all the systems within the scope of license renewal. This review revealed five systems (System 68, Spent Fuel Storage; System 70, Refuel Pool; System 76, Secondary Sampling System; System 103, Emergency Diesel Generator HVAC [ heating, ventilation, and air conditioning /;
and System 120, Barriers and Barrier Penetrations) that were identified as being within the scope of license renewal but not having component supports within the scope of the commodity evaluation provided in Section 3.1 of the LRA. Please identify the scope of component supports from these five systems that are included within the scope of the aging management review (AMR) under the component supports commodity groups. Indicate whether any of these five systems have no component supports that require an AMR.
BGE Responac Spent Fuel Storage (68) component supports are addressed in the cranes and fuel handling commodity evaluation.
Refueling Pool (70) is part of Containment and has no supports.
Barriers and Barrier Penetrations (120) (fire walls, ceilings, floors, doors, etc.) are part of other structures and have no supports.
Secondary Sampling System (76) is not within the scope oflicense renewal.
The Diesel Generator Building HVAC System (103) was inadvertently omitted from the list due to its location in the BGE LRA and the manner in which the aging of its components are being managed.
In the LRA, Emergency Diesel Generator HVAC was reviewed by comparison with the Control Room HVAC, as discussed in Section 5. llc. The aging management of System 103 is discussed in Section 5.l lC.l.4.
The changes needed due to this inadvertent omission are detailed in Attachment (2).
NRC Ouestion No. 3.1.2 Subsection 3.l A.l.1 includes a statement that the system's seismic structural boundary extends beyond the valve to the first seismic anchor or " equivalent." Provide a discussion to explain what kind of piping support arrangement is " equivalent" to the " seismic anchor."
BGE_ Response This term " equivalent" means a series of supports and changes in a piping geometry that combine to provide restraint to the piping in six degrees of freedom beyond the safety-related (SR) pressure boundary. It refers to some situations where we used an arrangement other than the classical seismic anchors. For instance, we have six snubbers on the main steam piping at the K-line (the wall between the Turbine Building and Auxiliary Building) arranged to provide restraint in six degrees of freedom.
We also have instances where we credit the concrete walls as anchors.
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j A*ITACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT l
REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE l
STRUCTURAL SUPPORT NRC Ouestion No. 3.1.3 Page 3.1-1 of Section 3.1 described that the Seismic Qualification Utility Group (SQUG) guidance was used as one of the sources for grouping the component supports and was used for the baseline inspections. As stated on page 5 of Supplemental Safety Evaluation Report No. 3.1.2 (SSER-2)
[ Reference IJ the qualification of seismic adequacy of equipment (including supports) in older operating l
nuclear plants does not address the aging effects of equipment. The SSER-2 also stated that the staff will not accept any claim that the experience data collected by the SQUG for the Unresolved Safety I
Issue A-46 program adequately addressed the aging effects of equipment. Provide a justification for using the Generic Implementation Plan (GIP) 2 for scoping component supports.
BGE Response Baltimore Gas and Electric Company has not credited SQUG GIP for aging management. Credited programs for supports are summarized in Table 3.1-4. The SQUG GIP approach is one source for grouping supports. We see no issue in using our Seismic Verification Project (SVP) techniques as one of the sources for grouping component supports.
NRC Ouestion No. 3.1.4 Page 3.1-1 of Subsection 3.1.1.1 provides the definition of component supports,"a component sunoort is defined as the connection between a system, or component within a system, and a plant structural member (e.g., the concrete floor or wall, structural beam or column, or ground outside the plant buildings)." From the review of Section 3.1, it is not clear that the steel structural frames used for the support of piping systems were treated as component support or as structural components. If the steel structural frames are considered as components, which of the aging management programs (existing or new) will be used for managing the aging effects of the steel structural frames?
BGE Response The piping support frames are treated as component supports. They will be managed by Calvert Cliffs Administrative Procedure MN-1-319," Structure and System Walkdowns." Those that support piping in the inservice inspection (ISI) scope will also be inspected per American Society of Mechanical Engineers (ASME)Section XI. Many will also be inspected as part of the additional Baseline Walkdown Inspection Program.
NRC Ouestion No. 3.15 Page 3.1-1 in Section 3.1 includes a statement that the structures AMR considered the effects of aging caused by the surrounding environment, while the component supports AMR considered the effects of aging caused by the supported equipment (thermal expansion, rotating equipment, etc.) as well as the surrounding environment. Clarify how the aging effects of the supported equipment was considered in the AMR for the component supports.
B.GE Response l
The " effects of aging caused by the supported equipment" were considered. Please see page 3.1-1.
I The intent of that statement is to emphasize the potential effects of local phenomena on the component supports - what might be considered as " loading dependent" rather than " environment r
dependent." Some examples are loads imparted on the suppoits by vibrating equipment such as pumps and fans, flow induced vibration in piping systems, and thermal expansion.
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i A'ITACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR Tile COMPONENT SUPPORTS AND PIPING SEGMENTS TIIAT PROVIDE STRUCTURAL SUPPORT NRC Ouestion No. 3.1.6 Please address the following questions related to the commodity description and the boundary for component supports:
Are all types of fasteners (such as bolts, nuts, clips, clamps, brackets, etc.) used to attach a.
component supports to components and component supports to structures included within the scope of component supports requiring an AMR7 If so, in what section of the LRA is the AMR of fasteners addressed? If not, provide a justification for not including fasteners within the scope of an AMR.
- b. For fasteners that rely on welded connections to the components (e.g., pipe stanchions with j
welded Attachment to a pipe or a piece of equipment), identify if the welds are considered part of the fastener, component being supported or the component support. Identify where in the LRA is the AMR for these fasteners and welds are located, or provide a justification for not including these fasteners and welds within the scope of an AMR.
Structural steel members such as supplementej steel members (e.g., HVAC duct supports c.
labeled as " rod hanger trapeze supports) de not identified as within the scope of component supports. Identify where in the LRA the AMR for these components is addressed or provide a justification for not performing an AMR of these components.
BGE Res_nonse Attachments / fasteners to the line commodities (piping, conduit, etc.) are included with the a.
component supports. They are generally not mentioned specifically. The walkdowns conducted under Procedure MN-1-319 will detect degraded conditions. There is no separate AMR for fasteners.
Attachments / fasteners to the structures (anchor bolts and expansion anchors) are included twice -
in the component supports Section 3.1.2 and in the structures (BGE LRA Sections 3.3A,3.3B, 3.3C,3.3D, and 3.3E). High strength anchor bolts are discussed on pages 3.1-41 through -44.
- b. In our AMR, the welds and fasteners are generally not identified specifically. They are considered part of the supports. Discussions of welds and fasteners are found, for example, on pages 3.1-15,3.1-16,3.1-21,3.1-22,3.1-25,3.1-35,3.1-36,3.1-37 and 3.1-39 of the BGE LRA.
c.
We intended this to be " rod hanger, trapeze supports" as written in Table 3.1-3, but inadvertently omitted the comma in some places in the LRA, such as Table 3.1-2.
This is addressed in Attachment (2).
NRC Ouestion No. 3.1.7 Page 3.1-2 in Subsection 3.1.1.1 includes the statement that supports for tubing are included in Section 6.4 of the LRA entitled " Instrument Lines." How is the distinction made (or boundary) between piping and tubing for defining the scope to be covered under Section 3.1 versus Section 6.47 BGE Res_nonse Plant drawings and other plant information indicates the boundary between piping and tubing.
Standard industry practice is used to differentiate between piping and tubing.
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ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE STRUCTURAL SUPPORT Baltimore Gas and Electric Company LRA Section 6.4, page 6.4-2, indicates that supports for tubing are included in the Instrument Line Commodity Evaluation (of Section 6 'd, and supports for small bore piping are included in the Component Supports Commodity Evaluation, Section 3.1.
NRC Ouestion No. 3.1.8 Table 3.1-1 on page 3.1-3 defines the systems within the scope of license renewal containing supports within the commodity evaluation. This table does not include the Steam Generator Blowdown System; Containment Isolation Group; Control Room and Diesel Generator Building HVAC Systems. Identify the section within the LRA that addresses the AMR for the associated supports for these systems and structures or provide ajustification for not including them within the scope of components requiring an AMR.
BGE Respnnse All of the systems included in this question have been included in the Component Supports commodity evaluation as follows:
The Steam Generator Blowdown System is part of the Main Steam System (083), which is included in Table 3.1-1.
The systems included in Section 5.5, " Containment Isolation Group," of the BGE LRA (Fire Protection (013), Plant Heating (029), Demineralized Water and Condensate Storage (037), Plant Water (051), Plant Drains (053), Waste Gas (069), and Liquid Waste (071)], are listed individually in Table 3.1-1.
The Control Room HVAC System is included in Table 3.1-1, as HVAC (030). The words " Control Room" were inadvertently omitted from the system name in that listing.
Please see the response to Question 3.1.1 for a discussion of the Diesel Generator Building HVAC System.
NRC Ouesting No. 3.1.9 In Table 3.1-2, only the rod hanger trapeze supports are listed for the HVAC ducting supports. Based on the staff's experience, unistrut type of supports are widely used for the HVAC ductworks in operating nuclear power plants. Clarify if the rod hanger trapeze type of support is the only type of support used for the HVAC ducting systems. If any other type of support is used for the HVAC ducting systems, identify where in the LRA these supports are addressed or provide a justification for not subjecting these components to an AMR.
RGE Response We intended this to be " rod hanger, trapeze supports." and this correction is made in Attachment (2).
This is meant to include Unistrut (or equal) types of light steel framing members, which are also in l
common use as electrical raceway supports.
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Also, there are some instances of HVAC duct support frames made of structural steel members (similar to piping support frames). These should be included as support types for HVAC Ducting i
Supports in Table 3.1-2 and Table 3.1-3. Their aging management is included with the Group 2 I
discussions on pages 3.1-23 through 3.1-29.
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ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS TilAT PROVIDE STRUCTURAL SUPPORT NRC Ouestion No. 3.1.10 Table 3.1-2 cnly identifies ring foundations for supports of the flat bottom field-erected vertical tanks.
Provide the basis for not considering the degradation due to aging (loose anchors, general corrosion of anchor chairs and long anchor bolts, etc.) of the anchorage systems in the component support AMR.
BGE Response The anc5or bolts for the ring foundations and the chairs were considered in the AMR. Baltimore Gas and Electric Company LRA Table 3.1-3 indicates that ' General Corrosion of Steel' and " Loading Due to Thermal Expansion of Piping / Component' are plausible for ' Equipment Support Type - Ring Foundation for Flat-bottom Vertical Tanks,' and are discussed in Groups 2 and 6, respectively.
Please see BGE LRA Section 3.1, page 3.1-18, and BGE response to NRC Question No. 3.1.15 for a discussion on loss of clamping force, i.e., loose bolts.
NRC Ouestion No. 3.1.11 Provide a discussion of how dynamic loading (e.g., vibrations) aging effects for the anchorage systems of elements inside electrical cabinets (such as relays) are managed.
BGE Response The discussion requested is available in Section 6.2, " Electrical Commodities," of the BGE LRA, under Group 5. As noted there, dynamic loading for panels is limited to the emergency diesel j
generator engine auxiliary motor control center panels. They are subject to the effects of vibration induced by and associated with the periodic testing of the emergency diesel generator. Such dynamic loading can cause the failure of welds, and failure or degradation of fasteners, hardware, and supports.
There are no practical ways to mitigate the effects. Discovery is by an age-related degradation inspection (ARDI), as described on page 6.2-20 of the BGE LRA.
NRC Ouestion No. 3.1.12 Table 3.1-3 indicates that general corrosion is not plausible for frames and saddles. Please provide the basis for this conclusion.
RGE Response Table 3.1-3 indicates that general corrosion of steel is plausible for frames and saddles.
NRC Ouestion No. 3.1.13 l
Based on the staff's experience, " loose bolts" (high strength bolts, anchor bolts, etc.) due to vibration is a l,
common type of aging effect of component supports with bolt-connections. Provide the basis for excluding this as an applicable aging effect. If applicable, please include a discussion of how the plant operating and maintenance history support this conclusion.
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A'ITACI1 MENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS TilAT PROVIDE STRUCTURAL SUPPORT BGE.Restannac We agree that vibratory loads are significant for bolted connections, and included both equipment and hydraulic vibration sources in Table 3.1-3. " Loose bolts" is an effect, rather than an ARDM. That effect and its management are discussed in Section 3.1 of the BGE LRA in Groups 1 and 5.
HRC Ouestion No. 3.1.14 Provide the basis for excluding concrete cracking as an applicable aging effect requiring an aging management program for the flat-bottom vertical tank ring foundation.
BGE Response On page 3.1-39 of the BGE LRA, concrete cracking was identified as an effect of loading due to thermal expansion for the ring foundation for flat-bottom vertical tanks. The Group 6 discussion of aging management program (s) on pages 3.1-38 and 3.1-40 identifies the programs that would lead to i
discovery of concrete cracking. Specifically, all of the ring foundations for flat-bottom vertical tanks were subject to the SVP baseline inspection, which included checks for grout / concrete local deterioration. Some of the ring foundations are also included in the ISI Program, which includes a check for concrete damage. The results of the SVP baseline and continual Isis concluded that no additional actions, other than follow-on activities discussed on page 3.1-40, are needed.
NRC Ouestion No. 3.1.15 Regarding expansion anchors and embedded anchors, which are commonly used for the connections between the component supports and structural components (walls, floors and beams), please clarify the following:
- a.. Any loss of clamping force over time (age-related degradation) associated with expansion anchors should be properly managed, because it will affect the stiffness properties of supports and will change the behavior of components under dynamic loading such as an earthquake. Please clarify how the loss of clamping force was addressed in the AMR for these components. If not addressed, provide the basis for not addressing the loss of clamping force for these components.
- b. The cracking of surrounding concrete (age-related degradation) that typically occurs around concrete expansion and embedded anchors was not identified as a potential aging effect. Provide the basis for not considering this as a potential aging effect.
c.
Provide the basis for not including corrosion of steel chairs, loose long anchor bolts, and deterioration of the nozzle between tanks and connected pipes within the scope of an AMR.
Based on the staff's experience, these components would have been expected to be addressed within the " support /ARDM combination" Group 6.
BGE Respenst a.
Loss of clamping force associated with expansion anchors is discussed on pages 3.1-17 and 3.1-18 of the LRA. Baltimore Gas and Electric Company considers failure of concrete expansion anchors more of a design / installation issue rather than an aging issue. Ilowever, to be conservative, BGE credited the follow-on activities discussed on pages 3.1-19 through 3.1-21 for the aging management of expansion anchors.
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A'ITACHMENT (1)
RESPONSE TO REQUEST FOR ads)lTIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS TIIAT PROVIDE STRUCTURAL SUPPORT
- b. Cracking at anchor bolts rarely occurs. NUREG/CR-5434," Anchor Bolt Behavior and Strength During Earthquakes," describes the special steps needed to cause cracks in the NRC-sponsored anchor bolt testing program. Concrete cracking is usually the result of concrete shrinkage, a j
relatively quick phenomenon. As noted on page 3.1-18, American Concrete Institute (ACl)
Standard ACI-209R says 91% of shrinkage occurs in the first year,98% in 5 years, and 100% in 20 years. Therefore, cracking due to shrinkage is not considered an ARDM.
Concrete cracking was identified as an effect of aging of Group 1, pipe supports, for the ARDMs loading due to thermal expansion of piping / component on pages 3.1-12 and 3.1-14 of the LRA. It was also identified as an effect of aging of Group 6 frames and saddles and ring foundation for the ARDM loading due to thermal expansion. The demonstration of aging management for these ARDMs is provided in the discussion for Group 1 on pages 3.1-10 through 3.1-22 of the LRA, and for Group 6 on pages 3.1-38 through 3.1-41 of the LRA.
Tanks and piping connected to them are addressed in the LRA sections for the applicable fluid c.
systems. Please see BGE response to NRC Question No. 3.1.10 concerning anchor bolts and chairs.
NRC Ouestion No. 3.1.16 Please clarify the following questions related to the baseline walkdowns or inspections described on pages 3.1-6 and 3.1-7.
Will the baseline walkdowns (or inspections) involve any actions other than visual observations?
a.
If not, explain how will cracks associated with incipient fatigue failures or with bolt cracking be detected.
b.
What parameters will be reviewed and/or inspected and what acceptance criteria wi!! be used?
Please clarify how the baseline procedure implements expansion of the sample size and scope c
based on the findings from the initial sampling? For example, if an ARDM is identified for a specific support-type sample, then will all supports for that " type" be inspected and will the scope be increased for other support types having a similar environment, design, or loading?
- d. General corrosion of steel is identified as an ARDM that applies to all support types. Will every support be included in the baseline walkdown/ inspection? If not, describe the process and the basis that will be used to determine the walkdown/ inspection sample size?
The LRA states that follow-on will be undertaken if evidence of significant aging is found.
e.
Clarify what is meant by significant aging? Provide examples of"significant aging" and what elements would be included in the follow-on actions. Also, what actions are taken if the identified ARDM is not significant at the time of baseline inspection?
BGE Response a.
The actions included in the additional baseline walkdown inspections are delineated on pages 3.1-17, -18, and -19 of the LRA for the Group I components (piping supports - general corrosion of steel, loading due to hydraulic vibration or water hammer, and loading due to thermal expansion of piping / components),3.1-27 and -28 for the Group 2 components (cable raceway supports, HVAC ducting supports, and equipment supports - general corrosion of steel),
and 3.1-43 for the Group 7 components (frames and saddles inside containment / loss-of-coolant accident restraints-stress corrosion cracking of high strength bolts).
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ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR Tile COMPONENT SUPPORTS AND PIPING SEGMENTS TilAT PROVIDE STRUCTURAL SUPPORT Fatigue is not a plausible ARDM for any of these supports or their bolting (see pages 3.1-8 and -9 of the LRA). There cannot, therefore, be any failures caused as a result of this phenomenon.
The high strength bolting of the safety injection tank supports is the only bolting included in these additional baseline walkdowns for which bolt cracking (stress corrosion cracking, specifically) is deemed to be plausible. This bolting is 1-1/4", A354, Grade BC. As such, it has a minimum tensile strength of 125,000 psi. Per Electric Power Research Institute (EPRI) NP-5769,
" Degradation and Failure of Bolting in Nuclear Power Plants," materials with specified minimum tensile strengths of <l50,000 psi may be screened from stress corrosion cracking evaluations. In keeping with the contents of NP-5769, the Good Bolting Practices reference manuals, NUREG-1339, " Resolution of Generic Safety Issue 29: Bolting Degradation or Failure in Nuclear Power Plants," and Generic Letter 91-17, " Generic Safety Issue 29, Bolting Degradation or Failure in Nuclear Power Plants," BGE has provided the NRC with its position on high strength bolting and the performance of additional testing in its response to Question 10 in Reference (2).
For conservatism, however (see the last two paragraphs on page 3.1-41 of the LRA), this bolting has been included in the scope of these additional baseline walkdowns for a one-time inspection using Section XI ISI procedures and their inspection criteria. This inspection will serve to document the condition of the safety injection tank support bolting and provide a basis for determining the extent of future aging management activities for it. [See also the response to Question 3.1.24.]
b.
See the first paragraph of the response to Question 3.1.16.a.
See the first paragraph of the response to Question 3.1.16.a. The increase in sample size will be c.
on a system and, where applicable, an environmental basis. For example, the entire Plant Heating System (over 4" piping) is included within the scope of these baseline walkdowns. If during the inspection of a sample ofits suppons for general corrosion, a condition is found that warrants an increase in sample size, the location of that found condition and its environmental conditions, i
compared to the rest of the system, will be taken into account when expanding the system walkdown sample size. If it is in an environment that is more conducive to corrosion than the environment for other pans of the system, the sample size will be increased based on the system supports that exist in that environment. If the condition is found to exist in an environmental condition that is not as conducive to corrosion as other parts of the system, then those other parts of the system will also be included in the new population sample,
- d. See the first paragraph of the response to Question 3.1.16.a.
e.
Significant aging will be determined by the inspectors performing the baseline walkdowns using the guidelines provided in plant procedure MN-1-319, specifically for the inspection of the different types of piping supports. This site maintenance procedure has superseded PEG-7, System Walkdowns, which is referenced in Section 3.1 of the BGE LRA.
It has been implemented to moet the requirements for evaluating structure and system material condition in accordance with the Maintenance Rule at Calvert Cliffs. The results of the baseline walkdowns will be documented as stated in the LRA and will be provided to the system engineers. The subsequent follow-on periodic walkdowns that occur, per the requirements of MN-1-319, by the system engineers will have the baseline results for continued condition monitoring purposes. The MN-1-319 walkdowns also have specific walkdown documentation requirements.
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ATTACHMENT (1)
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SECMENTS TIIAT PROVIDE STRUCTURAL SUPPORT NRC Ouestion No 3.1.17 Table 3.1-3 lists potential and plausible ARDMs for component supports. Please clarify the following related to the headings and potential ARDMs.
Provide the basis for excluding mechanical wear as an ARDM for supports containing pins, a.
springs, sliding plates, etc., from an AMR.
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- b. For general corrosion of steel, is corrosion attack by any medium other than water or moisture considered (e.g., chemical attack due to leaks, spills, or effluents)?
Are any materials other than steel and elastomer elements used in component supports c.
(e.g., Teflon coated or Lubrite plates)?
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- d. Did you include thermal striping and thermal stratification in your assessment of thermal expansion loading? If not, provide a justification for excluding these ARDMs fVom the scope of your AMR.
Referring to the ARDMs shown in Table 3.1-3, discuss the consideration given to possible e.
interaction between individual ARDMs. (As an example, vibratory loads in conjunction with irradiation embrittlement might be a very critical combination.)
BGE Response
'Ihis has not been excluded from AMR. It isjust not included as a separate specific ARDM. It is a.
implicit in the AMRs for the ARDMs loading due to rotating / reciprocating machinery, loading due to hydraulic vibration or water hammer, and loading due to thermal expansion of piping / components. These are the only plausible ARDMs evaluated in Section 3.1 where there is the potential for relative motion between support subcomponents. The potential adverse effects due to this relative motion (including wear) and their discovery are discussed in the Group 1, Group 4, Group 5, and Group 6 sections of Section 3.1 of the BGE LRA.
- b. Yes, corrosion of component supports due to boric acid leakage, in locations where that is possible, was considered; however, it was deemed to be not plausible. Evaluation for plausibility resulted in the conclusion that the system engineering walkdowns (MN-1-319), operator rounds and walkdowns (NO-1-200 and NO-1-107), and the Boric Acid Inspection Program (MN-3-301) would result in the discovery of crystal formation at the onset of leakage at its source before it could get bad enough to leak onto any supports.
c.
Teflon coated steel plates are used for the sliding surfaces of supports for in-scope heat exchangers. The Teflon is considered a solid lubricant and is not explicitly discussed in the LRA.
The purpose of the Teflon was taken into consideration during evaluation of the aging effects due l
to thermal expansion for Group 6 supports.
Lubrite plates constructed of cast manganese bronze with a mastic lubricant are used for the sliding surfaces of supports for the reactor vessels and steam generators. The reactor vessels' Lubrite plates are addressed in Section 4.2 of the LRA, and the steam generators' Lubrite plates are addressed in Section 3.3n of the LRA. (Also, see Attachment 2 of Reference 3)
Othenvise, materials not descr bed in LRA Section 3.1 are not used for supports.
- d. Yes, support reactions due to 6ermal expansion have been included as part of the support qualification. When conditions scch as thermal stratification are identified, and are shown to impact support loading, the support gealification is re-assessed for the increased loads.
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Our Methodology does not specifically require the evaluation of the interaction between individual ARDMs. However, as part of our AMR process, our research would identify known synergistic ARDM combinations and they would be appropriately considered.
> NRC OuestioqEo. 3.1.18 Please clarify the following concerns regarding the information described in Table 3.1-3:
He loading due to rotating / reciprocating machinery has the potential to affect many of the a.
supports listed in the table. Provide the basis for the "N/A" and "not plausible" determination for supports other than electrical raceways, electrical cabinets and instruments, and tanks potentially affected by rotating / reciprocating machinery loads,
- b. Provide the basis for the "not plausible" determination for piping frame and stanchion supports and for metal spring isolators and fixed base supports potentially alTected by loading due to hydraulic vibration or water hammer.
Provide the basis for the "not plausible" and "N/A" determination for piping frame and stanchion c.
supports, for metal spring isolators and fixed base supports, and for loss-of-coolant accident restraints potentially affected by loading due to thermal expansion of piping and/or components.
- d. Provide the basis for the "not plausible" determination for supports potentially affected by stress corrosion cracking of high strength bolts.
Provide the basis for the "not plausible" determination for supports potentially affected by e.
radiation embrittlement of steel.
f.
Provide the basis for the "not plausible" determination for supports potentially affected by grout / concrete local deterioration.
- g. Provide the basis for the "not plausible" devrmination for supports potentially affected by lead anchor creep.
BGE Response a Baltimore Gas and Electric Company excluded (marked N/A) fatigue due to rotating / reciprocating equipment as a potential ARDM for piping and HVAC duct supports and certain types of equipment supports. Loading due to rotating / reciprocating equipment causes high-cycle, low-stress fatigue, which is potential for supports of rotating or reciprocating components that are anchored to concrete. Some concrete components in Calvert Cliffs structures l
are subject to high cycles of low-level repeated load. These components were designed in I
accordance with ACI-318-63, which limits the maximum design stress to less than 50 percent of the static stress of the concrete. The concrete fatigue strength is about 55 percent ofits static strength at 7
the extremely high cycles (>10 cycles) ofloading. Therefore, fatigue will not degrade any concrete component and requires no further evaluation.
Equipment bolted to structural steel could experience fatigue failure of the bolts; however, such failure could only occur if the bolting were improperly designed or installed without adequate preload. His type of failure would occur within weeks or months, not years, after installation; this failure is visually detectable and usually results in a change in vibration tha't the vibration monitoring program would detect.
Some structural steel supports are subject to high cycle, low-level repeated loads from rotating / reciprocating equipment operation. Rotating machinery speeds are usually 1800 rpm, l
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RESPONSE TO REQUEST FOR ADDITIONAL INFORfetATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR TIIE COMPONENT SUPPORTS AND PIPING SEGMENTS TilAT PROVIDE STRUCTURAL SUPPORT 3600 rpm, or 5400 rpm. Thus the vibration frequencies generated are multiples of 30 Hz - 30,60, or j
90 Hz. Unless the machinery is out-of-balance, the loads are small.
He most significant repetitive loads are from flow-induced vibration, especially in the main steam piping. The frequency range is 2-40 Hz. An intermediate frequency of 20 Hz suggests about 2x10 cycles over the first 40 years. The fatigue " shelf" of metals is on the order of 10 cycles.
7 This means that fatigue damage to steel components is not age-related, so we do not expect damage to the plant unless there are modifications. However, if modifications are not properly engineered, vibratory loads cause failures within a few weeks to months, rather than years.
The "not plausible" determination for elastomer vibration isolators logic is that the elastomers reduce the stresses on the steel components. Elastomer degradation is addressed in " elastomer hardening." The discussion begins on page 3.1-29 of the BGE LRA.
- b. Structural steel pipe supports are subject to high cycle, low-level repeated loads from hydraulic vibration. He most significant repetitive loads are from flow-induced vibration, especially in the main steam giping. The frequency range is 2-40 Hz. An intermediate frequency of 20 Hz suggests about 2x10' cycles over the first 40 years. The fatigue " shelf" of metals is on the order of 10' cycles. This means that fatigue damage to steel components is not age-related, so we do not expect damage to the plant unless there are modifications. However, if modifications are not t
properly engineered, vibratory loads cause failures within a few weeks to months, rather than years.
Please also see the discussion in 3.1.18.a above, and BGE's response to NRC Question 3.1.19 regarding threaded fasteners in these supports.
For piping frame and stanchion supports, there are few cycles of thermal loading, and thermal c.
expansion is usually treated as an additional static load. However, these supports are designed for friction loads due to thermal expansion that are small relative to other design loads, so fatigue is not a concern. Please see BGE's response to NRC Question 3.1.19 regarding threaded fasteners in these i
supports.
Metal spring isolators provide ample allowance for thermal effects, so this class of equipment is 3
marked "N/A." For small to moderate size fixed-base equipment, internal thermal effects are small.
The equipment is considered an anchor and the piping is designed to allow thermal expansion away from the equipment. Large equipment bases are designed for thermal effects.
Supports designed for loss-of-coolant accident loading, such as those for the pressurizer and reactor coolant pumps, are designed so thermal expansion is accommodated without significantly loading the supports, so this type is marked "not plausible."
- d. Please see discussion in the response to NRC Question Nos. 3.1.16.a and 3.1.24.
e.
Electric Power Research Institute Report TR-103842, " Class I Structures License Renewal Industry Report," Revision 1, cites changes in yield strength and ductility when steel is subjected to fluence above 10'8 neutrons /cm. A Sandia National Laboratory study (Reference 4) reported no change at 2
slightly lower limits. The maximum fluence for component supports is considerably lower.
Therefore, this ARDM is not plausible for component supports.
f.
Industry experience has shown that supports anchored in concrete that experience static or limited dynamic loading are not subject to grout or local deterioration from environmental factors alone.
Deterioration of grout and localized concrete from loading stressors is considered separately under other ARDMs (loading due to rotating / reciprocating equipment, hydraulic vibration / water hammer, and thermal expansion.)
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' STRUCTURAL SUPPORT l
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- g. Lead anchors degrade by creep at room temperature. However, the current Calvert Cliffs design standsid for pipe and pipe supports does not allow the'use of lead anchors. Discussions with personnel involved with equipment installation concluded that cinch (lead) anchors may have been used to attach some lightweight, NSR electrical equipment to block walls. Since wall-mounted l
equipment imposes dead kmds on anchors, load relaxation due to creep would occur quickly.
Therefore, this mechanism is considered "not plausible."
NRC Ouention No. 3.112
~
Based on the staff's experience, a large number of frame types of piping supports are fabricated with
' threaded fasteners. If the bolted piping frame supports are used, clarify the basis for the following conclusion, "the aging effects are not expected to prevent the piping frames from performing their intended support function," described on page 3.1-11; and the conclusion, "while hydraulic vibration or water hammer and thermal expansion have been observed, the aging efTects are not expected to prevent the pipe frames from performing their intended support function and these ARDMs are considered to be not plausible for this kind of supports," on page 3.1-12.'
BGE Response There is only a small percentage of piping frames at Calvert Cliffs with threaded fasteners, and most are welded frames. The discussions on pages 3.1-11 and 3.1-22 describe stanchions along with the piping frames; the stanchions may also contain threaded fasteners. Therefore, BGE now considers the ARDMs " loading due to hydraulic vibration or water hammer" and " loading due to theimal expansion of piping / component" as plausible for these component support types because of the potential for the threaded fasteners to become loose. This determination is consistent with that made for other component supports with threaded fasteners, and the aging management programs will be the same as discussed in Group 1, Aging Management Program (s), starting on page 3.1-14 of the LRA. On page 3.1-8 of the BGE LRA, Table 3.1-3, under both " Piping Frames and Stanchions Outside Containment" and " Piping Frames and Stanchions Inside Containment," change the "not plausible" entries for " Loading Due to Hydraulic Vibration or Water Hammer and Loading Due to Thermal Expansion of Piping / Component," to "/ (1)"." Also, add a note to the bottom of the Table as follows: "" For consideration of threaded fasteners only." Baltimore Gas and Electric Company continues to consider the fatigue and wear concerns related to the subject loading conditions as not plausible for these component supports. Please refer to the response to NRC Question 3.1.18 for further information, l
l NRC Ouestion No. 3.1.20 A statement was made in the application that the ASME Section XI ISI for component supports includes a visual examination of a prescribed sampling of the systems covered by the program. In addition to the sampling criteria adopted from the ASME Code,Section XI (as stated in the last paragraph of p
L page 3.1-14), provide a description of the criteria for sample expansion (how the sample size of L
component supports are to be expanded when degradations are identified discussed on page 3.1-15).
l BGE Response In accordance with ASME Section XI IWF-2430, when the results of component support examinations require corrective actions in accordance with the provisions of ASME Section XI, the component supports immediately adjacent to those requiring corrective action shall be examined.
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' Also, the examinations shall be extended to include additional supports equal in number and similar in type, design, and function to those initially examined during the inspection.
If results of these additional examinations require corrective measures in accordance with ASME Section XI, the remaining component supports within the system of the same type, design, and function as described in the paragraph above shall be examined.
1 NRC Ouestion No. 3.1.21 With regard to the description in the second paragraph of page 3.1-17, please clarify the following:
j a.
The second sentence states that the sample approach will be comparable to the approach required by ASME Section XI for piping supports of ASME Class 3 systems. Clarify the definition of the word " Comparable." Identify the specific differences and describe why are these differences being implemented.
i
- b. The fourth and fifth sentence state that these walkdowns document the condition of the piping supports within the scope of license renewal for all piping s'upport types, except piping frames outside the containment. If an active corrosion mechanism is found during the additional sampling baseline walkdowns for pipe hangers outside the containment, then the inspection scope for that system would be expanded to pipe frame supports outside containment. Provide justification why the pipe frame supports outside the containment are included in the scope only when an active corrosion mechanism is found during the additional sampling baseline walkdowns for pipe hangers outside the containment.
BGE Response
~
a.
" Comparable" in this case means that, like the ASME Section XI Class 3 inspections, these Additional Baseline Walkdown Inspections will be performed on a sampling basis such that the discovery of a " discrepant" condition will result in the escalation of the sample size to include a larger percentage of the support population. Since this is a one-time " inspection" to establish and i
document the condition of the scoped supports as a benchmark, it differs from the ASME inspections that are performed on a prescribed periodic basis such that the entire sample population is examined four times over the course of the plant's operation. Our support population sample for the Additional Baseline Walkdowns will be determined, on a system basis, using our ARDI sampling methodology and escalated, if required, as discussed in the response to Question 3.1.16.c. Like the ASME Section.XI Class 3 methodology, the increased sample size will be determined based on an engineering evaluation of the conditions that have been found to exist. Also, like the ASME methodology, the inspection will be limited to greater than 4" piping supports. Subsequent to, and concurrent with, the performance of this baseline inspection, system l
inspections will be regularly performed per the requirements of Procedure MN-1-319. That procedure applies to 100% of all systems, notjust the systems or portions of systems within the scope oflicense renewal. The baseline inspections will serve to provide a specific benchmark of the condition of the supports that are within the scope of license renewal as a tool for the i
{
continued use of MN-1-319 for the balance of the current licensing period, as well as the period of extended operation.
- b. The License Renewal Rule does not require baseline inspections. We planned sampling baseline inspections on 13 additional systems. These are on the population of what we termed " pipe hangers," which includes spring hangers, constant load supports and rod hangers. Since ISI 13
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inspectors occasionally find loose bolts on these types of pipe supports, ARDMs were considered more likely on them than on frames.
Any frame degradation will be discovered by system walkdowns under Procedure MN-1-319. If the piping is in the scope of the ISI Program, hanger inspections will also detect any plausible degradation.
l NRC Ouestion No. 3.1.22 Page 3.1-18 states that "None of the failure modes is expected to be affected by age-related effects, such as anchor-bolt relaxation or concrete shrinkage because:" bolt preload in the anchor is not counted on for anchor function. Once an anchor is " set" by torque, anchor function is maintained by the irrevmible expansion of the anchor expansion ring or cone into the concrete. Summarize the information that provides the basis for this conclusion. Based on the staff's experience, once tlw anchor bolt is " set," the result of anchor-bolt relaxation or concrete shrinkage will cause the anchor-bolt function change due to l
the reduction of anchor-bolt stiffness (the stiffness of anchor-bolt systems will decrease with time, and only the anchor strength is maintained) and, in turn, the reduction of anchor-bolt stiffness will modify the dynamic behavior of the supported components.
BGE Response This is an engineering interpretation of informs + ion presented in EPRI NP-5228-SL, " Seismic Verification of Nuclear Plant Egipment Anchorage," especially in Volume 1. It addresses the failure mechanisms listed, all of which are related to anchor strength. The reviewer makes a point on reduction of stiffness, which may affect dynamic behavior. This also is addressed in the EPRI document. Please refer to the response to Question No. 3.1.15-a.
NRC Ouestion No. 3.1.23 Page 3.1-23 states that the Group 2 " support /ARDM combination" includes all 15 component support types within the three component support groups (cable-tray supports, HVAC ducting supports, and equipment supports). This section also provides a description on page 3.1-26 that the aging management approach for the three component support groups rely on inspections performed by the SVP for eight support-types, inspections performed by the ISI Program for three support-types, and additional sampling baseline walkdowns for two support-types. Please clarify what are the two support types that are not covered by these three baseline walkdown activities. Are they the two support types for which no baseline walkdowns were required? If so, what is the basis for this determination?
BGE Response The table below summarizes the baseline inspections that either have been or will be performed for each of the 15 component support types in question. There is only one component support type for which no baseline inspection was deemed to be required. This was the HVAC Support Ducting l
Outside Containment. The reason for this was that ducting supports outside Containment are constructed of the same materials, and are located in the same building areas, as the cable trays and raceways that were included in the SVP walkdowns. These supports were found to have no active ARDMs. Because the HVAC supports are of similar configuration, are constructed of the same materials, and are located in the same controlled environments, i.e., the Auxiliary Building, Control Room, and Diesel Generator Buildings, it was judged that these HVAC supports were bounded by those SVP walkdowns.
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_ RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS'FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE STRUCTURAL SUPPORT 1
. BASELINE INSPECTION PROGRAM -
l
~ COMPONENT SUPPORTTYPES
-. ISI
'SVP.
1 ABl* -
Trapeze, Cantilever, & other Cable Raceway y
Support Types, Outside Containment Trapeze, Cantilever, & other Cable Raceway j
l Support Types,Inside Containment HVAC Ducting Supports, Outside Containment HVAC Ducting Supports, Inside Containment
/
Elastomer Vibration Isolators Outside j
Conta, ment m
Electrical Cabinet Anchorage, Outside j
j Contamment Electrical Cabinet Anchorage,inside j
Containment Equipment Frames and Stanchions for j
Instruments & Batteries, Outside Containment li Equipment Frames and Stanchions for j
Instruments & Batteries, Inside Containment l-Frames and Saddles for Tanks & Heat j
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Exchangers, Outside_ Containment Frames and Saddles for Tanks & Heat j
j j,
Exchangers,Inside Containment -
Metal Spring Isolators & Fixed Bases, Outside j
Containment l.
Metal Spring isolators & Fixed Bases, Inside j-j Containment Loss-of-Coolant Accident Restraints
/
L.
Ring Foundations for Flat-Bottom Vertical jo j
L Tanks Additional Baseline Inspection Inadvertent omissions from the listings on page 3.1-27 and into -28 of the LRA. These are i
addressed in Attachment (2).
NRCDyestion No. 3.L14 Ermally, ' resistance or susceptibility to stress corrosion cracking of high strength steel bolts is established by hardness of the bolt material. Discuss what plans, if any, do you have to check the hardness of the bolts either from in place bolts or bolting in the warehouse. If applicable, provide hardness data for the bolting material as necessary to support the response.
BGE Response This issue is discussed in the response to Question No.10 of the set of 248 requests for additional information in Reference (5). These requests were answered in a letter in Reference (2). Baltimore Gas and Electric Company's response to Question No.10 concluded that a commitment to hardness 15 I
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testing was not required and provided the basis for that position. Also please see the response to
- Question No. 3.1.16.a above.
j NRC Ouestion No. 3.1.25 Describe the visual inspection activities performed during the SVP walkdown that were used to identify j.
potential ARDM effects such as loosening of bolted connections or loss of weld integrity. Please I
identify what documentation is used to implement these inspection activities.
BGE Response Walkdowns in the SVP were conducted in accordance with the GIP-2. The NRC's acceptance is documented in SSER-2.
The visual inspections applicable to component supports are documented in accordance with the GIP.
The forms are available onsite. The inspections are in three categories:
1.
Direct inspections of equipment anchorages for mechanical and electrical " equipment" identified as in the scope of the SSER; these were supplemented by anchorage calculations and a sampling program of torque tests;
- 2. General area inspections to identify any hazards to equipment within scope; and
- 3.,Walkdown of all electrical raceway supports to identify the limiting cases for analysis.
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NRC Ouestion No. 3.1.26 Section 3.1.A.2 indicates that piping segment beyond the SR/non-safety-related (NSR) boundary to the l
first seismic restraint is considered as structural support for the system pressure boundary isolation valve.
Therefore, piping segments beyond the SR/NSR boundary are classified as Seismic Category I up to and including the first seismic anchor. This section further states that given the similarity of the piping materials for piping within the SR pressure boundary, to these outside this boundary that are designed I
and maintained to SR requirements, any material degradation identified on the piping segments within the SR pressure boundary would lead to an evaluation for generic implications on the NSR side of this boundary. The staffinterprets this statement as a commitment that the licensee will evaluate these NSR piping segments only if some aging degradation has been identified on the SR piping segments. Since these NSR piping segments have the intended safety function of providing structural support to the SR piping and boundary isolation valves, provide a justification for not performing the applicable aging management activities for detecting applicable aging effects of the NSR piping independent of degrad; tion identified with the SR piping.
BGE Response l
The piping and its supports will be walked down in accordance with Procedure MN-1-319, so
(
degradation will be detected well i advance of any safety problems.
Since the NSR piping segments are credited with structural support vice maintaining the pressure boundary, the stipulations are less restrictive on these NSR piping segments.
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RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR THE COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE STRUCTURAL SUPPORT NRC Ouestion No. 3.1.27 Section 3.1.2 states that some supports are inaccessible either because they are located underwater (in spent fuel pools or refueling water storage tanks), or because they are located in high radiation areas.
The section further states that it may not be possible to perform a visual walkdowa of these supports.
ilowever, other inspection techniques (e.g., remote video) may be recommended under the ARDI Program if they are viable. The ARDI Program will either sample some of these supports, sample other accessible supports that are similar in design and/or environment, or will provide an analysis that will document why any inspection is not required. Please summarize the scope of the inspection activities, the inspection methods to be used, the frequency of inspections, the criteria used to determine that frequency, and the basis for this criteria related to the visual inspections /walkdowns activities. If an analysis has been used to determine that an inspection is not needed, provide sufficient information related to the analysis tojustify this determination.
BGE_Reaggn_ae The ARDI program for component supports is being developed. As noted on pages 3.1-18 and -19, it will consider the points mentioned in the question. See also response to Question No. I1.4 in Reference (6).
NRC Ouestion No. 3.1.28 Are there any parts of the systems, structures, or components described in this section that are inaccessible for inspection? If so, describe what aging management program will be relied upon to maintain the integrity of the inaccessible areas. If the aging management program for the inaccessible areas is an evaluation of the acceptability ofinaccessible areas based on conditions found in surrounding accessible areas, please provide information to show that conditions would exist in accessible areas that would indicate the presence of or result in degradation to such inaccessible areas. If different aging effects or aging management techniques are needed for the inaccessible creas, please provide a summary to address the following elements for the inaccessible areas: (1) Preventis e actions that will mitigate or prevent aging degradation; (2) Parameters monitored or inspected relative to degradation of specific structure and component intended functic,ns; (3) Detection of aging effects befze loss of structure and component intended functions; (4) Monitoring, trending, inspection, testing frequency, sad sample size to ensure timely detection of aging effects and corrective actions; (5) Acceptance criteria to ensure structure and component intended functions; and (6) Operating experience that provides objective evidence to demonstrate that the effects of aging will be adequately managed.
BGE Response Baltimore Gas and Electric Company can access all structures and components described in this section if required, with the exception of those discussed in BGE's response to Question No. 210 in Reference (2).
References 1.
NRC Letter to All Unresolved Safety Issue (USI) A-46 Plant Licensees Who are Members of the Seismic Qualification Utility Group (SQUG), dated May 22,1992, " Supplement No. I to Generic Letter (GL) 87-02 That Transmits Supplemental Safety Evaluation Report No. 2 (SSER No. 2) on SQUG Generic Implementation Procedure, Revision 2, as Corrected on j
February 14,1992 (GIP-2)"
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RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION; INTEGRATED PLANT ASSESSMENT REPORTS FOR Tile COMPONENT SUPPORTS AND PIPING SEGMENTS THAT PROVIDE STRUCTURAL SUPPORT 2.
Letter from Mr. C. H. Cruse (BGE) ta the NRC Document Control Desk, dated February 14,1997, " Response to Request for Additional Information; Baltimore Gas and Electric Company's Integrated Plant Assessment Systems and Commodity Reports" 3.
Letter from Mr.
C.
H.
Cruse (BGE) to NRC Document Control Desk, dated November 19,1998, " Response to Request for Additional Information for the Review of the Calvert Cliffs Nuclear Power Plant, Units 1 & 2, Integrated Plant Assessment Reports for Structures and Electrical Commodities, and Errata" 4.
Sandia National Laboratory, SAND 92-2420, MEA-2492, " Accelerated 54 C Irradiated Test of Shippingport Neutron Shield Tank and HFIR Vessel Materials," January 1993 5.
Letter from Mr. S. C. Flanders (NRC) to Mr. C. H. Cruse (BGE), dated August 30, 1996,
" Request for Additional Information Regarding the Baltimor: Gas and Electric Company Integrated Plant Assessment Systems and Commodity Reports Submitted May 22,1996" 6.
Letter from Mr. C. H. Cruse to NRC Document Control Desk, dated November 12,1998,
" Response to Request for Additional Information for the Review of the Calvert Cliffs Nuclear Power Plant, Units 1 & 2, Integrated Plant Assessment, Generic Areas" 1
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i ERRATA TO SECTION 3.1, COMPONENT SUPPORTS; L
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LICENSE RENEWAL APPLICA1: 6 l
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. Baltimore Gas and Electric Company Calvert Cliffs Nuclear Power Plant November 19,1998 t
ATTACHMENT (2)
ERRATA FOR SECTION 3.1, COMPONENT SUPPORTS; LICENSE RENEWAL APPLICATION The following changes apply to Section 3.1," Component Supports," of the Baltimore Gas and Electric Company Licehse Renewal Application:
On page 3.1-3, in Table 3.1-1, the second column should end with "(103) Emergency Diesel e
Generator HVAC."
On page 3.1-5, in Table 3.1-2, the first set of" Associated Systems," for Spring Hangen Constant e
Load Supports...," should include "071" between "067" and "083."
On page 3.1-5, in Table 3.1-2, the first line after "HVAC Ducting Supports" should read "HVAC Ducting Supports Outside Containment" instead of " Rod Hanger Trapeze Supports Outside Containment," and the " Associated Systems" column for this row should read "030 032103" vs.
just "030 032."
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On page 3.1-5, in Table 3.1-2, the second line afler "HVAC Ducting Supports" should read e
"HVAC Ducting Supports Inside Containment"instead of " Rod Hanger Trapeze Supports Inside Containment."
On page 3.1-5, in Table 3.1-2, the " Associated Systems" in the bottom line, for " Ring Foundations for Flat-Bottom...," should read "008 023 037 052" instead of "008 023 036 037 052."
On page 3.1-8, in Table 3.1-3, the last two columns, in the row under "HVAC Ducting Supports,"
should read "HVAC Ducting Supports Outside Containment" and "HVAC Ducting Supports Inside Containment," respectively.
For the third full paragraph on page 3.1-27, which starts "For component supports subject to baseline inspection under the ISI Program...", the parenthetical content at the end of that paragraph should read as follows: "... frames and saddles for tanks and heat exchangers inside containment, LOCA restraints, and ring foundations for flat-bottom vertical tanks)."
The last sentence on page 3.1-27 into the top of 3.1-28 should read as follows: "The component support types subject to additional sampling walkdowns are HVAC ducting supports inside containment, electrical cabinet anchorage outside containment (anchorage for sampling system hoods only), electrical cabinet anchorage inside containment (for six radiation monitors), and frames and saddles for tanks and heat exchangers inside containment (safety injection tank anchor bolting only)."
On page 3.1-38, the first sentence of the second paragraph of the discussion under Group 6, e
" Materials and Environment," should read as follows: " Ring foundations for flat-bottom vertical tanks are located both outdoors and inside tornado enclosures. The internal environment of these structures is not controlled and is, therefore, subject to atmospheric temperature, pressure, and humidity."
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