ML091400535

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E-mail from P. Tamburro of Exelon Corp. to J. Richmond of USNRC, Regarding Drywell Inspection Specification for Oyster Creek, IS-328227-004, Rev. 14, Functional Requirements for Drywell Containment Vessel Thickness Examinations
ML091400535
Person / Time
Site: Oyster Creek
Issue date: 08/18/2008
From: Tamburro P
Exelon Corp
To: Richmond J
NRC Region 1
References
FOIA/PA-2009-0070 IS-328227-004, Rev 14
Download: ML091400535 (43)
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Peter.Tam burro@exeloncorp.com Monday, August 18, 2008 11:00 AM John Richmond Calvin.Taylor@exeloncorp.com Drywell Inspection Specification IS-328227-004, Rev 014, 20070516, Functional Requirements fo.pdf

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Drywell Inspection Specification Date: Mon, 18 Aug 2008 11:00:12 -0400 Message-ID:

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I Specification IS-328227-004 Specification for Oyster Creek Functional Requirements for Drywell Containment Vessel Thickness Examinations j4:T-y/

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Preparation: Peter Tamburro I (

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Reviewed By: Dave Olszewski c--

5/4/a o-Engineering Approval: Howie Ray

,"r i.I4, Revision 14 May 16, 2007

/

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 2 of 39 1.0 Scope This specification establishes requirements for Non Destructive Examination (NDE) of the Oyster Creek Drywell Containment Vessel. This specification has been revised due to Licensing Renewal Commitments in reference 2.20. The following inspections and examinations are addressed:

1) UT (Ultrasonic Thickness) Examinations at selected locations on the inside of the Drywell at elevation 5 1' 2"; 51' 10"; 60' 10" and 87' 5". The purpose of these examinations is to monitor long term corrosion rates at these elevations. These inspections are required to meet Oyster Creek License Renewal commitment item 7 in reference 2.20 [CM-1].
2)

Visual coating inspections (VT-I) of the coating applied on the Drywell Vessel exterior in 1992 in the former sandbed region. Also, Visual Inspections (VT-I) will be performed on the seal/caulking at the junction between the sand bed region concrete/floor and the embedded drywell vessel. The purpose of these inspections is to ensure that the condition of the coating is acceptable and meets Section Xl, Subsection IWE requirements. These inspections are required to meet Oyster Creek License Renewal commitment items 2, 4, 12, and 21 in reference 2.20 [CM-1 and CM-2].

3)

UT Examinations at selected locations inside the Drywell at elevation I I' 3" (the.

former sandbed region). The purpose of these examinations is to verify that the external coating is effectively protecting the drywell vessel and that external corrosion is insignificant. These inspections are required to meet Oyster Creek License Renewal commitment items I and 21 in reference 2.20 [CM-1].

4) External UT Examinations of locally thin areas in the 10 Sandbed Bays. The purpose of these examinations is to measure locally thin areas that were identified during external inspections in 1992 and 2006. These inspections are required to meet Oyster Creek License Renewal commitment items 9, 14, and 21 in reference 2.20 [CM-I].
5) Inspect the sandbed drains to ensure these lines are not clogged. These inspections will ensure that the sandbed drains are not clogged and water will not collect in the former sandbed region and challenge the coating.
6) UT Examination and visual inspection of the drywell shell within the two trenches inside thedrywell on concrete floor (El. 10'-3") in bays 5 and 17. The purpose of these examinations is to verify that internal corrosion is insignificant.

These inspections are required to meet Oyster Creek License Renewal commitment items 5, 16 and 20 in reference 2.20 [CM-i].

7) UT Examination of the weld joint at Elevation 23' 6 7/8" in four locations. The purpose of this examination is to provide an indication that the drywell vessel at this weld has not significantly degraded. This UT inspection will be performed through existing internal coating. These inspections-are required to meet Oyster

'Creek License Renewal commitment item I I in reference 2.20 [CM-1].

IS-328227-004 Function Requirements for Dtywell Containment Vessel 77Tickness Evaminations Rev. 14 Page 3 of 39

8) UT Examination of the weld joint at Elevation 7 1' 6" in four locations. The purpose of this examination is to provide an indication that the drywell vessel at this weld has not significantly degraded. This UT inspection will be performed through existing coating. These inspections are required to meet Oyster Creek License Renewal commitment item 10 in reference 2.20 [CM-1].

IS-328227-004 Function Requirements for Di well Containment Vessel Thickness Examinations Rev. 14 Page 4 of 39 2.0 Reference Unless otherwise noted, the latest revision applies.

2.1 ASME B&PV Code Section V, 1995 Edition 2.2 ASME B&PV Code Section XI, Subsection IWE, 1992 Edition 2.3 C-1302-187-E310-030 Revision 1, "Statistical Analysis of Drywell Thickness Through September 1996" 2.4 TQ-AA-122, "Qualification And Certification of Nondestructive (NDE)

Personnel" 2.5 ER-AA-335-004, "Manual Ultrasonic Measurements of Material Thickness and Interfering Conditions" 2.6 GPUN Sketch, No. SK-S-89 2.7 GPUN Sketch, No. SK-S-85 2.8 C-1302-187-E310-037 Revision 3, "Statistical Analysis of Drywell Vessel Thickness Data" 2.9 C-1302-187-5320-024, Revision 2, "Drywell External Ultrasonic Testing Evaluation in Sandbed" 2.10 GPUN Drawing 3E-187-29-001, Revision 0, Drywell Shell Stretch-Out".

2.11 ER-AA-335-018, "Detailed General, VT-1, VT-IC, VT-3 and VT-3C, Visual Examination of ASME Class MC and CC Containment Surfaces and Components" 2.12 OCIS-328227-003,"Repair of Concrete Floor Removed in Drywell For UT Readings" 2.13 NRC SER date November 1, 1995 - Changes in the Oyster Creek Drywell Monitoring Program 2.14 ECR 05-00275, Drywell Vessel inspections through 2004.

2.15 License Renewal Commitment Letter -from M.P. Gallagher to NRC dated April 4, 2006 (2130-06-20284) 2.16 ER-OC-330-1006, "First 10 Year Containment (IWE) Inservice Inspection Program Plan and Basis, Draft.

(

IS-328227-004 Function Requirements for Di',well Containment Vessel Thickness Examinations Rev. 14 Page 5 of 39 2.17 PBD-AMP-B. 1.27, Program Basis Document ASME Section XI, Subsection IWE.

2.18 Deleted 2.19 Commitments CM-1 PASSPORT AR 00330592.27, Oyster Creek Licensing Renewal Commitments Associated with Aging Management Program B. 1.27, ASME Section XI, Subsection IWE (Steps 1.0)

  • CM-2 PASSPORT AR 00330592.33, Oyster Creek Licensing Renewal Commitments Associated with Aging Management Program B. 1.33, Protective Coating Monitoring and Maintenance Program 2.20 AmerGen Letter 2130-07-20464 to US NRC Date 2/15/2007 "Oyster Creek Licensing Renewal Commitments Associated with Aging Management Program B. 1.27, ASME Section XI, Subsection IWE".

2.21 C-1302-187-E310-041 Revision 0, "Statistical Analysis of Drywell Vessel Sandbed Thickness Data 1992, 1994, 1996 and 2006"

I 1S-328227-004 Function Requirements for Dirwe/I Containment Vessel 77hickness Examinations Rev. 14 Page 6 of 39 3

Requirements 3.1 Non Destructive Examinations 3.1.1 Personnel Qualification 3.1.1.1 Personnel conducting Ultrasonic Examinations shall be qualified in accordance with ER-AA-335-004.

3.1.1.2 Personnel conducting Visual Examinations shall be VT-1 qualified in accordance with ER-AA-335-018.

3.1.2 Examination Procedures 3.1.2.1 NDE UT examinations shall be performed in accordance with ER-AA-335-004 and this specification.

3.1.2.2 Visual Examination of the Drywell Vessel coating on the exterior surface of the former sandbed region and the internal portions of the trenches shall be performed in accordance with ER-AA-335-018.

3.1.3 Methodology and Equipment The UT examinations performed inside the Drywell shall be performed by one of the following methods:

3.1.3.1 Forty Nine Point Examinations 3.1.3.1.1 For these locations the inspector shall use a stainless steel template fabricated in accordance with Exhibit 2.

3.1.3.1.2 Prior to inspection remove the existing grease that has been previously applied on the area for corrosion protection.

3.1.3.1.3 At each location, the template shall be placed on the drywell vessel so that the notches on the template line up with the low stress die stamps that have been previously stamped on the surface of the drywell. The Inspector shall use a UT transducer that fits within the template within a clearance of 1/16".

IS-328227-004 Function Requirements for D,-w'ell Containment Vessel Thickness Examinations Rev. 14 Page 7 of 39 3.1.3.1.4 The UT transducer shall be positioned in the same orientation at each grid point. (I.e. the top of the transducer is always positioned to the top template).

3.1.3.1.5 After the UT inspection coat the location with Versilube G351 grease or an approved alternative.

3.1.3.2 Seven Point Examinations 3.1.3.2.1 For these locations the inspector shall use the same stainless steel template fabricated in accordance with Exhibit 2.

3.1.3.2.2 Prior to inspection remove the existing grease that has been previously applied on the area for corrosion protection.

3.1.3.2.3 At each location, the template shall be placed on the drywell vessel so that the notches on the template line up with the low stress die stamps that have been previously stamped on the surface of the drywell. The Inspector shall use a UT transducer that fits within the template within a clearance of 1/16". The inspector shall record only the 7 readings in the middle row.

3.1.3.2.4 The UT transducer shall be positioned in the same orientation at each grid point. (I.e. the top of the transducer is always positioned to the top of the template).

3.1.3.2.5 Use of the template, the UT transducer, and aligning it with the template notches to the stamp on the Drywell ensures that each individual reading is located within a 1/8" of previous readings.

3.1.3.2.6 After the UT inspection coat the location with Versilube G351 greaseor an approved alternative.

IS-328227-004 Function Requirements for Dryivell Containment Vessel Thickness Examinations Rev. 14 Page 8 of 39 3.1.3.3 Multiple Point Examinations within the two floor Trenches 3.1.3.3.1 For these two locations the inspector shall use the same stainless steel template fabricated in accordance with Exhibit 2. The template shall be used to locate multiple 7 by 7 grids.

3.1.3.3.2 Within each trench align the template so that the notches on the template line up with the low stress die stamps that have been previously stamped on the surface of the drywell (refer to Exhibit 5). The Inspector shall use a UT transducer that fits within the template within a clearance of 1/16".

3.1.3.3.3 The UT transducer shall be positioned in the same orientation at each grid point. (I.e. the top of the transducer is always positioned to the top of the template). The UT readings shall be taken through the existing coating.

3.1.3.4 Core Bore Locations The following specific location/grid points have core bore plugs.

Bay Area Points 11A 23, 24, 30, 31 17D 15,16,22,23 19A

__24,_25,_31,_32 19C 20,26,27,33 5/D12 (51-D1) 20, 26, 27, 28, 33, 34, 35 3.1.4 Inspection Schedule All inspections required by this specification shall be performed during the scheduled Refueling Outage for the years shown in the table

4. The schedule in Table 4 complies with the latest Oyster Creek License Renewal Commitments documented in reference 2.20 [CM-1 and CM-2].

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 9 of 39 3.2 Inspections 3.2.1 Internal UT Inspection of Upper Elevations [CM-1]

A total of nine locations are monitored for corrosion rates at elevation 51' 2"; 51' 10"; 60' 10" and 87' 5". Forty-nine individual UT readings shall be recorded at each of the nine locations in accordance with section 3.1.3.1. Table 1 below provides information for each of these locations.,

Table 1 - UDDer Elevation Inspection Location Location ID Bay Elevation Original Minimum NDE Data Acceptance sheet,

Criteria for each Individual Reading 5/D12 (51-D1) 5 50' 2" 87-026-26 0.607" 5-5 (51-5) 5 50' 2" 87-026-124 0.607" 13/31 (51-13) 13 50' 2" 87-026-126 0.607" 15/23 (51-15) 15 50' 2" 87-026-123 0.607" 13/32 (52-13) 13 51'10" 87-026-144 0.542" 50-22 1

60' 10" DWCV-R-0.539"

_005 9/20 (86-20) 9 87' 5" 87-026-30 0.543" 13/28 (86-28) 13 87' 5" 87-026-37 0.543" 15/31 (86-31) 15 87' 5" 87-026-38 0.543" 3.2.1.1 Acceptance Criteria With the exception of individual points positioned over core plugs (as documented is section 3.1.3.4) each individual reading less than the minimum value specified in Table 1 shall be entered into the corrective action program and evaluated by Engineering.

The acceptance criteria in Table I is based on the minimum recorded readings in 2006 (reference 2.8) and a 20 mil tolerance. The acceptance criteria is not based on the minimum required code thickness, which is less than the above values.

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 10 of 39 3.2.1.2 Data Retention All 49 readings values at each location shall be documented on an NDE data sheet and formatted in a 7 by 7 matrix, which corresponds to the template. The data sheet shall also include:

the date and time of the examination, location of core plugs (if applicable), the examination method, the ID number of the equipment, the ID number of the cal block, the location surface temperature, Examiner, Reviewer, the governing procedure, Location ID in accordance with Table 1. Forward the completed data sheets to Engineering.

3.2.1.3 Required Support and Tools 3.2.1.3.1 In order to provide access to the three inspection locations at elevation 87' 5",

temporary planking shall be provided as necessary at the top of the biological shield extending to the drywell wall.

3.2.1.3.2 Deleted 3.2.1.3.3 Prior to the UT inspection of each location remove the existing grease that was applied after the last inspection shall be removed.

3.2.1.3.4 After the UT inspection coat the location with Versilube G351 grease or an approved alternative.

DOCUMENTINO.

IS-328227-004 TITLE Functional Requirements For Drywell Containment Vessel Thickness Examinations REV

SUMMARY

OF CHANGE APPROVAL DATE 13 A complete revision resulting from commitments to the NRC for Oyster Creek Licensing Renewal life extension from 2009 to 2029. Revision 13 now provides requirements for the following:

1. UT Examinations at selected locations on the inside of the Drywell at elevation 51' 2"; 51"10"; 60'10" and 87' 5". These inspection were previously performed on a 4 year interval. However new acceptance criteria has been established for entering results into the Corrective Action System.
2.

Visual coating inspections of the coating applied on the Drywell Vessel in 1992 in the former sandbed region. These inspections were previously performed on a 4 year interval. However new acceptance criteria has been established for entering results into the Corrective Action System. In addition the inspection reflects addition commitments to perform a complete 100% inspection of all bays by 2009 and a complete 100% during the period of extended operation between 2009 and 2029.

3.

UT Examinations at selected locations on the inside of the Drywell at elevation 11' 3" (the former sandbed region). These inspections were previously performed in various intervals until 1996 at time which GPUN received approval from the NRC discontinue the inspections. However new licensing renewal commitments have been made to perform a complete 100% inspection of all bays by 2009 and an additional complete 100% inspection during the period of extended operation between 2009 and 2029. Also, acceptance criteria has been established for entering results into the Corrective Action System.

4. External Inspection and UT Examinations of 16 locally thin areas in Bays I and 13. This is a new licensing renewal commitment which is a one time inspection to be performed prior to the 2009.
5.

Inspection of the five sandbed drains to ensure these lines are not clogged. This is not a commitment. However it is considered prudent measure to ensure the drain lines are not clogged.

6. UT Examination and visual inspection of the drywell shell within the two trenches inside the dry-well on concrete floor (El. 10'-3") in bays 5 and 17. This is a new licensing renewal commitment that shall be performed once prior to the 2009.

Preparer - Peter Tamburro Reviewer -

Charles Schilling Manager -

Howie Ray

.1.

N0036 (1/99)

2 1

7.

UT Examination of a welds at Elevation 23' 6". This is a new licensing renewal commitment, which shall be performed once prior to the 2009 and once during the period of extended operation.

8.

UT Examination of a weld at Elevation and 71'6". This is a new licensing renewal commitment, which shall be performed once prior to the 2009 and once during the period of extended operation.

A complete revision resulting from commitments to the NRC for Oyster Creek Licensing Renewal life extension from 2009 to 2029 as documented in AmerGen Letter 2130-07-20464 (reference 2.20). Also, this revision incorporates lessons learned from the I R21 Inspections 14 Preparer - Peter Tarnbu7 Reviewer -

Dave Olszewski Manager -

Howie Ray-6A 07 N0036 (1/99)

Function Requirements forD *vell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page II of 39 3.2.2 Internal UT Inspection of Former Sandbed Region Elevations [CM-i]

3.2.2.1 Description A total of 19 locations are monitored for corrosion rates at elevation 11' 3". Individual UT readings shall be recorded at each location in accordance with section 3.1.3.1 and 3.1.3.2.'

Table 2 below provides information for each of these locations.

Table 2-Sandbed Elevation Inspection Location Location No of Bay Elevation Original Average Average Average ID points NDE Thickness Thickness Thickness Data based on based on based on sheet 1994 1996 2006 Inspections Inspections Inspections (inches)

(inches)

(inches) 9D 49 9

11' 3" 87-026-59 0.992 1.008.

0.993 11A 49 11 11' 3" 87-049-24 0.820 0.830 0.822 liC 49 11 11' 3" 87-049-37 0.894 0.951 0.898 13A 49 13 11' 3" 87-026-58 0.837 0.853 0.846 13D 49 13 11' 3" 87-026-67 0.959 0.990 0.968 15D 49 15 11' 3" 87-026-58 1.053 1.066 1.053 17A 49 17 11' 3" 87-026-58 1.017 1.058 1.015 17D 49 17 11' 3" 87-049-26 0.810 0.848 0.818 17/19 49 17 11' 3" 87-026-66 0.970 0.980 0.969 19A 49 19 11' 3" 87-049-27 0.806 0.815 0.807 19B 49 19 11' 3" 87-049-28 0.824 0.837 0.847 19C 49 19 11' 3" 87-049-29 0.820 0.854 0.824 ID 7

1 11' 3" 87-026-54 1.101 1.151 1.122 3D 7

3 11' 3" 87-026-55 1.184 1.175 1.180 5D 7

5 11' 3" 87-026-56 1.168 1.173 1.185 7D 7

7 11' 3" 87-026-57 1.136 1.138 1.133 9A 7

9 11' 3" 87-026-60 1.157 1.155 1.154 13C 7

13 11' 3" 87-026-61 1.140 1.154 1.142 15A 7

15 11' 3" 87-026-62 1.114 1.127 1.121 3.2.2.2 Acceptance Criteria 3.2.2.2.1 With the exception of individual points positioned over core plugs each of the 49 individual readings less than 0.628" shall be I

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 12 of 39 entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on the minimum recorded readings in 2006 (reference 2.2 1) and a 20 mil tolerance. This acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.2.2.2 In addition Engineering shall calculate the average value of each location consistent with reference 2.3. The calculated average for each location shall be within +/- 0.020" of the values documented in table 2. Values not within +/- 0.020" shall be entered into the corrective action program and evaluated by Engineering and shall be subject to the following actions:

  • Perform additional UT measurements to confirm the readings. Notify NRC within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of confirmation of the identified condition 0 Conduct visual inspection of the external surface in the sad bed region in areas where any unexpected corrosion may be detected.

o Perform engineering evaluation to assess the extent of the condition and to determine if additional inspections are required to assure drywell integrity.

0 Perform operability determination and justification for continued operation, in accordance with plant procedures, until next scheduled inspection.

3.2.2.3 Data Retention Values at each location shall be documented on an NDE data sheet and formatted in either a 7 by 7 or a 1 by 7 matrix, which corresponds to the template. The data sheet shall also include:

the date and time of the examination, location of the core plugs, the examination method, the ID number of the equipment, the governing procedure, the ID number of the cal block, the location surface temperature, Examiner, Reviewer,

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 13 of 39 Location ID in accordance with table 2. Forward the completed data sheets to Engineering.

3.2.2.4 Required Support and Tools 3.2.2.4.1 Deleted 3.2.2.4.2 Prior to the UT inspection of each location remove the existing grease (with an approved cleaner), which was previously applied after the last inspection.

3.2.2.4.3 After the UT inspection coat the location with Versilube G351 grease or an approved alternative.

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 14 of 39 3.2.3 External UT Inspection of Locally Thin Areas in all Sandbed Bays [CM-1i 3.2.3.1 Description 3.2.3.1.1 Locate and perform UT Inspection of locally thin areas found during the external inspection of the Drywell in 1992 and 2006, These areas were identified in 1992 on NDE data sheets 92-072-01 through 92-072-26 and were located and inspected in 2006. The 2006 inspections results are documented on NDE datasheets 1R21LR-003, 004, 007, 009, 011, 013, 014, 016, 017, and 018 (Exhibit 7). Perform the UT inspection through the coating. Select UT equipment that is capable of subtracting the coating thickness from the vessel wall thickness.

3.2.3.1.2 The inspections shall capture the thinnest reading within the each area consistent with the results of the 2006 inspections.

3.2.3.1.3 The 2006 NDE datasheets 1R21LR-003, 004, 007, 009, 011,013,014, 016, 017, and 018 provide the location of each area (Exhibit 7). In addition the locations were marked during the 2006 inspections 3.2.3.1.4 After each UT inspection is performed, ensure the area remains permanently marked so that the same area can be easily located in future inspections.

3.2.3.2 Acceptance Criteria Readings less than 0.582" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on the minimum recorded reading in 2006 1

(reference 2.21) and a 20 mil tolerance. Acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.3.3 Data Retention UT readings for each location shall be documented on an NDE data sheet. The data sheet shall also include: the date and time of the examination, the examination method, the ID number of

IS-328227-004 Function Requirements for Dtywell Containment Vessel Thickness Examinations Rev. 14 Page 15 of 39 the equipment, the governing procedure, the ID number of the cal block, the location surface temperature, Examiner, Reviewer, Location ID in accordance with Table 3. Forward the completed data sheets to Engineering.

3.2.3.4 Required Support and Tools 3.2.3.4.1 Deleted.

3.2.3.4.2 The cavity in the former sandbed region is a confined space.

3.2.3.4.3 To provide access to the cavity in the former sandbed region, the station shall remove the sandbags and boron bags that fill each access man way.

3.2.3.4.4 After inspections per sections 3.2.3 and 3.2.4 are completed the station shall reinstall the sandbags and boron bags in each man way, unless this configuration has been replaced with a manway cover per an approved configuration change.

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 16 of 39 3.2.4 External Visual Inspection of the Sandbed Coating [CM-1 and CM-2]

3.2.4.1 Description 3.2.4.1.1 The external coating that was applied'in 1992 to the Drywell Vessel shall be inspected in accordance with ER-AA-335-018 and ASME Section XI subsection IWE.

3.2.4.1.2 Inspect exterior surfaces of the drywell for water and the concrete floor for ponding or standing water.

3.2.4.1.3 The entire surface from the base of the sand bed region concrete floor (El. 8' 11") to the top where the vessel rises into the 3" gap (El. 12' 3") shall be visually (VT-I) inspected. In the horizontal direction the inspection of one bay shall constitute all surfaces within 16 feet centered on the vent line (see Exhibit 3).

3.2.4.1.4 The inspection shall include a visual inspection of the caulking that was applied in 1992 at the interface between the former sandbed concrete floor and the drywell vessel (see Exhibit 4).

3.2.4.1.5 The inspection shall also identify cracks on the sandbed floor at the interface between the epoxy grout used in 1992 to rebuild the floor and the original concrete floor or walls.

Similar cracks were identified in the 2006 inspections. These cracks were sealed with a sealant in 8 of the 10 bays during the 2006 outage. The inspection shall include a visual inspection of the sealant installed in 2006.

3.2.4.2 Acceptance Criteria 3.2.4.2.1 Refer to Attachment 2 of procedure ER-AA-335-018. All surface areas with flaking, chipping, blistering, peeling, pinpoint rusting, cracking, chalking and discoloration

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 17 of 39 attributable to rust blooms shall be entered into the Corrective Action Program and evaluated by Engineering.

3.2.4.2.2 The caulking at the base of the Drywell shall be free of chipping, peeling, and cracking.

De-viation shall be entered into the Corrective Action Program and evaluated by Engineering.

3.2.4.2.3 The sealant in the floor cracks (installed in 2006) shall be free of chipping, peeling, and cracking. Deviation shall be entered into the Corrective Action Program and evaluated by Engineering.

3.2.4.2.4 Discoloration due to loose surface residue from surface wetting is acceptable so long as the coating below the residue has not degraded.

3.2.4.2.5 Minor flaking, chipping and peeling of the epoxy coating and caulking is acceptable.

Minor flaking, chipping and peeling is defined as follows: isolated flaking, chipping and peeling where: the loose coating is less than a 1/4/4 square inch, is on the surface of the coating or caulking and does not penetrate to the base metal. The purpose of this exception is to allow minor physical damage that may have been caused by personnel moving around in the sand bed region and is not indicative of a coating or caulking breakdown.

3.2.4.2.6 Documentation of degraded areas shall include the location of the area (i.e. X inches from the vertical weld and Y inches from the downcomer penetration weld), the size of the area, and the specific degradation. A color picture of degraded areas shall be taken and provided to Engineering.

3.2.4.2.7 Document bays where ponding or standing water, if any, was observed.

I

IS-328227-004 Function Requirements for Dywell Containment Vessel Thickness Examinations Rev. 14 Page 18 of 39 3.2.4.3 Data Retention Inspections shall bedocumented for each bay on an NDE data sheet. The data sheets shall also include: the date and time of the examination, the examination method, the governing procedure, Examiner, and Reviewer.

3.2.4.4 Required Support and Tools 3.2.4.4.1 Deleted 3.2.4.4.2 The cavity in the former sandbed region is a confined space.

3.2.4.4.3 The field shall also remove the sandbags and boron bags that fill each man way.

I 3.2.4.4.4 After Inspections per sections 3.2.3 and 3.2.4 are completed the station shall reinstall the sandbags and boron bags in each man way, unless this configuration has been replaced with a manway cover per an approved configuration change.

3.2.5 Sandbed Drain Line Inspection 3.2.5.1 Description The former sandbed cavity has five drain lines equally spaced around the sandbed (see Exhibit 4). The purpose of these drains I

is to drain the cavity should water be introduced into the former sand bed cavity. The drains exit the Drywell Pedestal at the base of the Pedestal in the Torus Room. Inspect these drains with a boroscope type video system to ensure they are not clogged. These drain lines shall be inspected on a frequency required on Table 4.

3.2.5.2 Acceptance Criteria Each drain line shall be free of blockage. Minor amounts of blockage (less than 15% of the cross sectional area) are I

acceptable. Lines with unacceptable blockage shall be entered in to the Corrective Action Program.

3.2.5.3 Data Retention Inspections shall be documented for each line on an NDE data sheet or in the PIMS Work Order including blockage less than 15%. The data sheets or PIMS Work Order shall also include:

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 19 of 39 the date and time of the examination, the examination method, Examiner, and Reviewer.

3.2.5.4 Required Support and Tools 3.2.5.4.1 Deleted 3.2.5.4.2 The cavity in the former sandbed region is a confined space.

I

IS-328227-004 Function Requirements for Diywell Containment Vessel Thickness Examinations Rev. 14 Page 20 of 39 3.2.6 Trench Visual and UT Examination [CM-11 3.2.6.1 Description 3.2.6.1.1

Background

In the mid 1980's two trenches were cut out of the Drywell floor at elevation 10' 3". The purpose of these trenches was to allow UT inspection of the Drywell Vessel below the removed concrete. The inspection results were captured on NDE data sheets 86-049-047 and 86-049-056 (reference 2.7). These trenches were then filled by the installation of a foam material (reference 2.11). In 2006 these trenches were opened by removing the foam and then visually inspected. The inspections found standing water in the bay 5 trench and the coating of the drywell vessel in both trenches was in poor condition. The coating was removed and the vessel was UT inspected. In addition the trench in bay 5 was slightly enlarged to allow inspection of an additional 6" at the bottom. This 6" area was then grouted over after the inspection. The results were documented in NDE data sheets I R2 I LR-023, 024, 025, 031, 032, 037, and 038. After the UT inspections the vessel surfaces in the trenches were coated with Versilube G351 grease or an approved alternative.

3.2.6.1.2 Perform the following inspections:

1) Inspect the trenches for water. If water is found then enter this condition into the corrective action system. Document the amount (level) of water and possible sources of the water. Chemistry shall sample the water.
2) Inspect the caulk sealant installed in 2006 on the edges of the trenches where the concrete meets the Drywell Vessel.

IS-328227-004 Function Requirements for Driwell Containment Vessel Thickness Examinations

. Rev. 14 Page 21 of 39

3) Remove the protective grease on the.

Drywell Vessel.

4) Perform UT inspections in each trench consistent with the scope and method of the 2006 inspections and Exhibit 5. The Drywell Vessel surface in both trenches has been permanently marked. Line up the notches on the template with the low stress die stamps (refer to Exhibit 5).
5) In the bay 5 trench remove the lower 6 inches of grout installed in 2006. Expose an additional 6" of vessel surface consistent with the area exposed in 2006 as shown in NDE data sheet IR21LR-031.

Re-grout as required to allow resealing concrete to the shell surfaces.

3.2.6.2 Acceptance Criteria 3.2.6.2.1 Visual Inspection Acceptance Criteria 3.2.6.2.1.1 Refer to attachment 2 of procedure ER-AA-335-018. All surface areas with flaking, chipping, blistering, peeling, pinpoint rusting, cracking, chalking, and discoloration attributable to rust blooms shall be entered into the Corrective Action Program and evaluated by Engineering.

3.2.6.2.2 Vessel Thickness Acceptance Criteria Readings less than 0.682" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on the minimum recorded readings in 2006 (reference NDE data sheetlR21LR-024 and 025), a 20 inil tolerance.

The acceptance criteria are not based on the minimum required code thickness, which is less than the above value.

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 22 of 39 3.2.6.3 Data Retention 3.2.6.3.1 Visual inspections shall be documented for each Trench on an NDE data sheet. The data sheets shall also include: the date and time of the examination, the examination method, the governing procedure, Examiner, and Reviewer.

3.2.6.3.2 All UT readings values within each trench shall be documented on an NDE data sheet and formatted in a 7 column format similar to NDE data sheets 1R21LR-023 and 025.

The data sheets shall clearly identify the order of each grid from the top to bottom.

The data sheet shall also include: the date and time of the examination, location of the core plugs, the examination method, the ID number of the equipment, the governing procedure, the ID number of the cal block, the location surface temperature, Examiner, Reviewer, Location ID in accordance with table 2.

3.2.6.4 Required Support and Tools 3.2.6.4.1 Deleted 3.2.6.4.2 Remove the existing protective grease.

3.2.6.4.3 Remove a small portion of concrete/grout in the bottom of the bay 5 to expose an additional 6" of Drywell Vessel surface. The amount of surface shall be approximately the same as the surface area exposed in 2006. Refer to NDE data sheet 1R21LR-03 i 3.2.7 After the UT inspection are complete coat the location with Versilube G351 grease or an approved alternative.

IS-328227-004 Function Requirements for Drnwell Containment Vessel Thickness Examinations Rev. 14 Page 23 of 39 3.2.7 UT Inspection of Weld Joint at Elevation 23' 6 7/8" [CM-i11 3.2.7.1 Background At elevation 23' 6 7/8" there is a circumferential weld which joins the bottom spherical plates and the middle spherical plates. This weld joins plates that are 1.154" thick to the plates that are 0.770" thick. The edges of the 1.154 thick plates were fabricated with a taper to provide a smooth transition to the thinner plates.

3.2.7.2 Locations 3.2.7.2.1 Four separate locations shall be inspected per the requirements of section 3.2.7.3. This shall include repeat inspection of the two locations in bays 15 and 17 inspected in 2006 (NDE data sheet 1R21R029 and 030).

3.2.7.2.2 This weld joint is located at nearly the same elevation as the grating at elevation 23' 6".

The 1.154 thick plates are located below the grating. The "as built" drawings do not provide enough information to determine if there is enough clearance between the grating and the side of the Drywell to allow NDE inspectors access to the lower plates.

Therefore the inspection locations will be selected by the NDE and Engineering, based on accessibility to the lower plate. To the extent possible the inspection locations shall be selected within Bays 13, 15, 17, 19 and or

1. These bays have historically experienced the most corrosion in the sandbed region. If necessary portions of the grating may have to be removed. Since the 2006 inspection were performed in bays 15 and 17, the two new 2008 locations should be, to the extent possible, selected from bays 13, 19, and 1.

3.2.7.3 Inspection Requirements 3.2.7.3.1 Inspection of'the 1.154" Plate 3.2.7.3.1.1 Dynamic UT inspections of the 1.154" thick plate shall be performed

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 24 of 39 through the existing coating below the taper (see Exhibit 6).

Dynamically scan an area that is a nominally of 6" wide by 6" high.

Record the average and maximum thickness. Also characterize and document all areas within this 6" by 6" area that are less than 0.96 inches thick.

3.2.7.3.1.2 During this first inspection, mark this area with a low stress dye stamp so that repeat inspections can be performed in the future. This shall be accomplished by marking two comers of the 6" by 6" area.

3.2.7.3.1.3 If UT inspection (per the above paragraphs) of the 1.154" thick plate cannot be performed due to interference between the grating and the side of the drywell and if the grating cannot be easily removed, document the discrepancy into the Corrective Action Process for evaluation by Engineering.

3.2.7.3.2 Inspection of the 0.770" plate 3.2.7.3.2.1 Dynamic UT inspections of the 0.770" plate shall be performed through the existing coating above

-the weld. Dynamically scan an area that is a nominally of 6" wide by 6" high (see Exhibit 6). Record the average and maximum thickness.

Also characterize and document all areas within this 6" by 6" area that are less than 0.740 inches thick.

3.2.7.3.2.2 During the first inspection, mark this area with a low stress dye stamp so that repeat inspections can be performed in the future. This shall be accomplished by marking two comers of the 6" by 6" area.

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 25 of 39 3.2.7.3.3 Inspection of the Weld 3.2.7.3.3.1 Dynamic UT thickness inspection of the weld between the two 6" x 6" areas described above. Grind the weld crown flat if necessary. fOO%

of the weld area shall be inspected.

3.2.7.3.3.2 Review of the original construction drawings for the drywell vessel (CBI drawing 9-0971 sheet 4, details "Joint R", "Joint D" and "Joint E")

show that this weld was required to be flush. Therefore, most likely "Flat Top" process will not be required.

However, it is possible the weld may have slight crown that was not completely flush. In this case the Flat Top process will simply remove the slight crown.

3.2.7.3.3.3 After the UT inspection is complete and if weld has been "Flat Topped" coat the exposed weld location with Versilube G351 grease or an approved alternative.

3.2.7.4 Acceptance Criteria 3.2.7,4,1 On the 0,770" thick plate and the weld, readings less than 0.628" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on the minimum recorded local readings found during the 2006 inspections (reference 2.21) and a 20 mil tolerance. This acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.7.4.2 On the 1.154" thick plate readings less than 0.847" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on the minimum recorded local

IS-328227-004 Function Requirements for Di*iell Containment Vessel Thickness Examinations Rev. 14 Page 26 of 39 readings found during the 2006 inspections (NDE Data sheet 1R21LR-029) and a 20 mil I

tolerance. This acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.7.5 Data Retention All readings and areas sizes for each location shall be documented on an NDE data sheet. In addition the location of the inspected area shall be clearly documented so that this same location can be inspection in the future. The data sheet shall also include: the date and time of the examination, the examination method, the ID number of the equipment, the governing procedure, the ID number of the cal block, the location surface temperature, Examiner, Reviewer, Location ID in accordance with table 3.

3.2.7.6 Required Support and Tools 3.2.7.6.1 Deleted 3.2.7.6.2 The weld in the area may be ground flat prior to the inspection.

IS-328227-004 Function Requirements for Dtywell Containment Vessel Thickness Examinations Rev. 14 Page 27 of 39 3.2.8 UT Inspection of Weld Joint at Elevation 71' 6" [CM-1]

3.2.8.1 Background At elevation 71' 6" there is circumferential weld which joins the transition plates (referred to as the knuckle) between the cylinder and the sphere. This weld joins the knuckle plates, which are 2 5/8" thick to the cylinder plates, which are 0.64" thick. The edges of the 2 5/8" thick plates were fabricated with a 3 to 12 taper to provide a smooth transition to the thinner plates.

3.2.8.2 Locations/Scaffolding 3.2.8.2.1 Four separate locations shall be inspected per the requirements of section 3.2.8.3. This shall include repeat inspection of the two locations in bays 15 and 19 inspected in 2006 (NDE data sheet 1R21R033 and 034).

Inspection of this weld joint in four I

locations will require the erection of scaffolding from the drywell platform at elevation 47'. The inside of the Drywell at this elevation is very congested. Therefore the NDE, Engineering, and the trade that will erect the scaffolding will select the actual location. This will ensure that the inspection and scaffolding erection will be performed safely. To the extent possible the inspection locations shall be selected within Bays 13, 15, 17, 19 and or 1. These bays have historically experienced the most corrosion in the sandbed region. Since the 2006 inspections were performed in bays 15 and 19, the two new 2008 locations should be, to the extent possible, selected from bays 13, 17, and 1.

3.2.8.3 Inspection Requirements 3.2.8.3.1 Inspection of the 2 5/8" plate 3.2.8.3.1.1 Dynamic UT inspections of the 2 5/8" thick plate shall be performed

IS-328227-004 Function Requirements for Drmv'ell Contoinment Vessel Thickness Examinations Rev. 14 Page 28 of 39 through the existing coating below the taper on the plate (see Exhibit 6).

Dynamically scan an area that is a nominally of 6" wide by 6" high.

Record the average and maximum thickness. Also characterize and document all areas within this 6" by 6" area that are less than 2.55 inches thick.

3.2.8.3.1.2 During this first inspection, mark this area with a low stress dye stamp so that repeat inspections can be performed in the future. This shall be accomplished by marking two comers of the 6" by 6" area.

3.2.8.3.2 Inspection of the 0.64" plate 3.2.8.3.2.1 Dynamic UT inspections of the cylinder plate shall be performed through the existing coating above the weld. Dynamically scan an area that is a nominally of 6" wide by 6" high. Record the average and maximum thickness. Also characterize and document all areas within this 6" by 6" area that are less than 0.585 inches thick.

3.2.8.3.2.2 During this first inspection, mark this area with a low stress dye stamp so that repeat inspections can be performed in the future. This shall be accomplished by marking two comers of the 6" by 6" area.

IS-328227-004 Function Requirements for Drywell Containment Vessel Th7ickness Examinations Rev. 14 Page 29 of 39 3.2.8.3.3 Inspection of the weld 3.2.8.3.3.1 Dynamic UT thickness inspection of the weld between the two 6" x 6" areas described above. Grind the weld crown flat if necessary. 100%

of the weld area shall be inspected.

3.2.8.3.3.2 Review of the original construction drawings for the drywell vessel (CBI drawing 9-0971 sheet 4, details "Joint R", "Joint D" and "Joint E")

show that this weld was required to be flush. Therefore, most likely "Flat Top" process will not be required.

However, it is possible the weld may have slight crown that was not completely flush. In this case the Flat Top process will simply remove the slight crown.

3.2.8.3.3.3 After the UT inspection is complete and if weld has been "Flat Topped" coat the exposed weld location with Versilube G351 grease or an approved alternative.

3.2.8.4 Acceptance Criteria 3.2.8.4.1 On the cylinder plate (nominally 0.64") and the weld, readings less than 0.429" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on minimum recorded readings found during the 2006 inspections (NDE Data sheet 1R21LR-033) and a 20 mil tolerance. This acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.8.4.2 On the knuckle plate (nominally 2 5/8")

readings less than 2.408" shall be entered into the corrective action program and evaluated by Engineering. This acceptance criteria is based on minimum recorded

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 30 of 39 readings during the 2006 inspections (NDE I

Data sheet 1R21LR-033) and a 20 mil tolerance. This acceptance criteria is not based on the minimum required code thickness, which is less than the above value.

3.2.8.5 Data Retention All readings and areas sizes for each location shall be documented on an NDE data sheet. In addition the location of the inspected area shall be clearly documented so that this same location can be inspected in the future. The data sheet shall also include: the date and time of the examination, the examination method, the ID number of the equipment, the governing procedure, the ID number of the cal block, the location surface temperature, Examiner, Reviewer, Location ID in accordance with table 3.

3.2.8.6 Required Support and Tools 3.2.8.6.1 Deleted.

3.2.8.6.2 To provide access to this welded joint, the station must erect scaffolding from elevation 47'.

3.2.8.6.3 The weld in the area may be ground flat prior to the inspection.

3.2.8.6.4 Remove the scaffolding.

4 Quality Assurance 4.1 The following work shall be performed in accordance with the Exelon Quality Assurance Program as follows:

4.1.1 UT and Visual Inspection shall be performed in accordance with approved procedures as described in section 3.1.2 and this specification.

Function Requirements for Driwell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 31 of 39 4.1.2 UT inspections for sections 3.2.1, 3.2.2 and 3.2.3 shall be performed with a template that meets the dimensional requirements in Exhibit 2 of this specification.

4.1.3 Resulting calculation(s) shall be developed and approved in accordance with Exelon approved procedures

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Page 32 of 39 Rev. 14 Table 4 - Ins pection Schedule [CM-I and CM-2]

Inspection 2006 2008 2010 2012 2014 2016 2018 2020 2022 2024 2026 2028 Internal UT Yes - all Yes - all Yes - all Yes -

Yes - all Yes - all Inspection in upper locations locations locations all locations locations elevations per location section 3.2.1 s

Internal UT Yes - all Yes - all Yes - all Yes - all Yes - all Yes - all Yes - all Inspection in locations locations locations locations locations locations locations sandbed region per section 3.2.2 External UT Yes - all Yes - all Yes - all Yes - all Yes L all Yes - all Yes - all Inspection of locations locations locations locations locations locations locations Locally Thin Areas in the Sandbed per section 3.2.3 Visual inspection Yes - Ali Yes - All Yes - All Yes - All Yes - All Yes - All Yes - All of Former Sandbed Bays Bays Bays Bays Bays Bays Bays coating per section 3.2.4 Inspection of Yes - all Yes - all Yes - all Sandbed drain lines locations tions per section 3.2.5 Internal UT Yes -

Yes -

Yes -

Inspection in Bay 5 and Bay 5 and Bay 5 and Trenches per 17 17 17 section 3.2.6

  • Note 1 Internal Visual Yes -

Yes -

Yes -

Inspection in Bay 5 and Bay 5 and Bay 5 and Trenches per 17 17 17 section 3.2.6

  • Note 1 UT Inspection of Yes - 2 Yes - 2 Yes -4 Weld Joint at Locations New Repeat Elevation 23' 6 Locations locations 7/8" per section and 2 Note*2 3.2.7 Repeat locations UT Inspection of Yes - 2 Yes - 2 Yes -4 Weld Joint at Locations New Repeat Elevation 71' 6" Locations locations per section 3.2.8 and 2 Note*2 Repeat locations

IS-328227-004 Function Requirements for Drywell Containment Vessel Thickness Examinations Rev. 14 Page 33 of 39 Note *1 - Termination of the trench inspections after 2010 assumes that no water is found in the trenches in the 2008 and 2010 refueling outages, and the NRC provides approval prior to the planning deadline for the 2012 outage in which case the trenches will be refilled with concrete. [CM-1]

Note *2 - Inspections at these locations will continue on an every-other-outage frequency if the corrosion rates at these locations are not bounded by rates identified through inspections of the upper drywell. [CM-1]

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 34 of 39 Exhibit 1 Typical Orientation of Inspection Locations in the Sandbed Region View - looking from inside the drywell A

B C

D Location IDs = Bay Number plus one of these letters: i.e. - "liD"

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 35 of 39 Exhibit 2 Template shall be made of Stainless Steal, approximately 0.30 inches thick, with 49 holes centered on a 1 inch pattern.

1'F +/- 1/31 (Typ.)

1 +1-1/Z1" (typ.)

00000 0000.10 0-. 0'0. '

O0

,0 0

l0l 0 0.0 0...

0 Diameter of each hole shall between 9/16" and 5/8".

1/16" by 1/4" slit centered on middle row or column 1" (Typ.)

Function Requirements for Dri'ell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 36 of 39 Exhibit 3 Inspect 16 feet Centered on Vent line rl1 4-1

).

i.

5, E

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 37 of 39 Exhibit 4 1-I 7>^Ywc-" *5#Ojz

/.P.

Inspect caulking at elevation 8' 11"

'~

E 4.

A Funciion Requirentenis for Dr ywell Containment Vessel Thickness Examinations IS-328227M004 Rev. 14 Page 38 of 39 Exhibit 5 Vessel Concrete Curb Concrete Curb Floor at Elevation 10'3" Trench Area 00 00 00 00 0 0 008 OOZOO "200 O-Q-

_0 2 0, 0 a V 0 0 0-0--

OOQQOOO goo 00 0 0[ 270 011ri 00 00 0000000 0000000 i 0 0 00 00 100 4

00 00

'0 OEI 0 0 LCO 0 0 0 0' 0 0 Align notches with permanent markings Elevation View of Trenches

Function Requirements for Drywell Containment Vessel Thickness Examinations IS-328227-004 Rev. 14 Page 39 of 39 Exhibit 6 Low Stress Dye Stamp to mark these corners Perform Dynamic scan in accordance with section 3.2.7 and 3.2.8 min. 6" W eld at Elevation 71' 6" or 23' 6 7/8" I

min. 6" F,

min.

Taper Region Flat top and inspect weld ner sections 3.2.7 Perform Dyna scan in accord:

with section 3.

and 3.2.8 mnce Z.7

/and 3.2.8 min. 6" Low Stress Dye Stamp to mark these corners Elevation View

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