DCL-07-085, Results of Steam Generator (SG) Tube Alternate Repair Criteria (ARC) Inspections for Unit 1 Fourteenth Refueling Outage

Results of Steam Generator (SG) Tube Alternate Repair Criteria (ARC) Inspections for Unit 1 Fourteenth Refueling Outage

ML072470188
Person / Time
Site:	Diablo Canyon
Issue date:	08/27/2007
From:	Jacobs D Pacific Gas & Electric Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DCL-07-085
Download: ML072470188 (57)

Text

W Pacific Gas and Electric Company' Donna Jacobs Diable Canyon Power Plant Vice President P. 0. Box 56 Nuclear Services Avila Beach, CA 93424 805.545.4600 August 27, 2007 Fax: 805.545.4234 PG&E Letter DCL-07-085 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Docket No. 50-275, OL-DPR-80 Diablo Canyon Unit 1 Results of Steam Generator (SG) Tube Alternate Repair Criteria (ARC)

Inspections for Diablo Canyon Power Plant Unit 1 Fourteenth Refueling Outag-e

Dear Commissioners and Staff:

In accordance with Technical Specifications (TS) 5.6.10.c and 5.6.10.d, provides the 90-day report of results of the Unit 1 SG Wstar (W*) ARC tubesheet inspections and calculated steam line break leakage from application of all ARC and non-ARC.

In accordance with TS 5.6.10.f, Enclosure 2 provides the 120-day report of results of the Unit I SG primary water stress corrosion cracking ARC inspections at dented tube support plate (TSP) intersections.

In accordance with TS 5.6.10.e, Enclosure 3 provides the 90-day report of results of Unit 1 SG voltage-based ARC inspections for TSP outside diameter stress corrosion cracking, prepared by Areva for PG&E. As concluded in Section 5.3 of Enclosure 3, there were no underpredictions, and reporting to the NRC in accordance with TS 5.6.10.g is not required.

There are no new or revised regulatory commitments as defined by the Nuclear Energy Institute 99-04, "Guidelines for Managing NRC Commitment changes,"

dated July 1999, in this report.

If you have any questions, please contact John Arhar at (805) 545-4629.

Sincerely, o

cobs A member of the STARS (Strategic Teaming and Resource Sharing) Attiance Caltaway

• Comanche Peak

• Diablo Canyon

• Palo Verde

• South Texas Project

• Wolf Creek

Document Control Desk August 27, 2007 Page 2 ddml/469/R0272302 Enclosures PG&E Letter DCL-07-085 cc:

cc/enc:

Diablo Distribution Michael A. Brown, NRC Acting Senior Resident Bruce S. Mallett, NRC Region IV Alan B. Wang, Project Manager NRR State of California, Pressure Vessel Unit A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Comanche Peak

• Diablo Canyon 9 Palo Verde

• South Texas Project

• Wolf Creek PG&E Letter DCL-07-085 ENCLOSURE 1 W* ALTERNATE REPAIR CRITERIA 90-DAY REPORT DIABLO CANYON POWER PLANT UNIT I FOURTEENTH REFUELING OUTAGE This report implements the Diablo Canyon Power Plant (DCPP) Technical Specification (TS) 5.6.10.c and 5.6.1O.d steam generator (SG) tube inspection reporting criteria.

Wstar (W*) Alternate Repair Criteria (ARC) was implemented for the sixth time in DCPP Unit 1 during the Unit 1 Fourteenth Refueling Outage (1R14) SG inspections and repairs that were completed in May 2007. One hundred percent of the SG tubes were inspected by bobbin from tube end to tube end, except for Row 1 and 2 U-bends. One hundred percent of the hot leg top of tubesheet (TTS) WEXTEX region was inspected by Plus Point in each SG. Cold leg TTS Plus Point inspections were not required.

Technical Specification 5.6.10.c Reporting Requirements DCPP TS 5.6.1 0.c requires that the results of the inspection of W* tubes be submitted within 90 days after initial entry into MODE 4 following completion of an inspection performed in accordance with TS 5.5.9. This enclosure provides the specific TS reporting requirements, and Pacific Gas and Electric Company's (PG&E) description of compliance.

A comprehensive list of axial primary water stress corrosion cracking (PWSCC) indications detected in the hot leg WEXTEX region during 1R14 Plus Point inspections are provided in Table 1. The following discussions provide references to columns in Table 1 where appropriate information is contained.

Identification of W* tube indications and indications that do not meet W*

requirements and were plugged.

Table 1 column labeled "W* Cand" identifies 17 tubes (containing 20 single axial PWSCC indications [SAI] within or below the W* length) that are categorized as W*

candidates (W* tubes) and left in service under W* ARC. There were no indications that did not meet W* requirements, and no indications were plugged because of failure to meet W* ARC.

Not included in Table 1 are circumferential outside diameter stress corrosion cracking (ODSCC) indications located at the top of tubesheet (in non-W* tubes) that were plugged because the crack type and location is excluded from application of W* ARC.

" Number of indications and location of the indications (relative to below the W*

transition [BWT] and top of tubesheet [TTS]).

1-1 PG&E Letter DCL-07-085 For each of the 20 indications, the lower crack tip (LCT) and upper crack tip (UCT) columns provide the elevation (inch) of the upper crack tip and elevation of the lower crack tip relative to the TTS. The "Dist UCT to TTS" column provides the distance (inch) between the upper crack tip and the TTS, accounting for nondestructive examination (NDE) uncertainty on locating the crack tip relative to the TTS. The "Dist UCT to BWT" column provides the distance (inch) between the upper crack tip and the BWT, accounting for NDE uncertainty on locating the crack tip relative to the BWT.

• Orientation (axial, circumferential, volumetric, inclined).

The "Ind" column provides the orientation of the indication. All indications are SAIs.

No indications are circumferential, volumetric, or inclined.

" Radial position of the tube within the tubesheet.

The "Tube Radial Position" column provides the radial position of the tube within the tubesheet.

" W* Zone of the tube.

The "W*ZONE" column provides the W* zone of each indication.

" Severity of each indication (estimated depth).

The "MD-adj" column provides the estimated maximum depth (MD) (percent through-wall) of each indication. The depth is the adjusted depth using the same techniques as PWSCC ARC depth sizing.

" Side of the tube in which the indication initiated (inside or outside diameter [ID/OD]).

The "ID/OD" column provides the side of the tube in which the indication initiated.

All indications are ID initiated (i.e., PWSCC).

" W* inspection distance measured with respect to the BWT or TTS (whichever is lower).

For the one hundred percent Plus Point hot leg TTS exam, the inspection extent relative to the TTS was specified as +2/-8 inches. Assuming no degradation in the W* length, 8 inches below the TTS constitutes the W* inspection distance. If degradation is detected in the W* region, the inspection extent must bound the calculated flexible W* length. The "W* Insp Ext wrt BWT" column lists the W*

inspection distances measured with respect to BWT for tubes in which axial PWSCC was detected. The distances are with respect to BWT because, in all 1-2 PG&E Letter DCL-07-085 cases, the BWT elevation was located lower than the TTS elevation. In all cases, the W* inspection distance was greater than or equal to the flexible W* length, as indicated by "Yes" in the "lnsp Ext Satisfied?" column.

" Length of axial indications.

The "Crack Length" column provides the crack length of each axial indication. For tubes with multiple cracks, the "Total Length" column provides the total (summed) length of individual cracks within the flexible W* length.

" Angle of inclination of clearly skewed axial cracks (if applicable).

No axial cracks were inclined, so this item is not applicable.

Verification that the upper crack tip of W* indications returned to service in the prior cycle remain below the BWT by at least the 95 percent confidence NDE uncertainty on locating the crack tip relative to the BWT.

The "Dist UCT to BWT" column in Table 1 provides the as-found elevation of the upper crack tip relative to the BWT, accounting for NDE uncertainty in locating the crack relative to the BWT. In all cases, the as-found upper crack tip for indications returned to service in the prior cycle is below the BWT, as indicated by "Yes" in the "UCT below BWT?" column.

" Updated 95 percent growth rate for use in operational assessment.

Of the 20 axial PWSCC indications in the hot leg WEXTEX region that were detected in 1 R14 as listed in Table 1, two were new indications and eighteen were repeat W* indications that had been left in service in the prior Unit 1 thirteenth refueling outage (1R13) inspection. All repeat indications were detected in 1R14.

The new indications were detectable in 1 R1 3 based on lookup reviews. As a result, 20 additional length growth rate data points were available for evaluation, and their average growth rate was 0.00 inch per effective full power years (EFPY) at Thot of 604 degrees, indicating negligible growth. After addition of the Unit 1 Cycle 14 data points, the updated W* growth rate distribution now consists of 370 data points from DCPP Units 1 and 2 over 12 cycles. The updated growth rate at 95 percent cumulative probability for all data is 0.100 inch per EFPY at 604 degrees. The W*

methodology requires that, if the new growth data and deletion of the oldest cycle(s) of growth data results in a minimum of 200 data points, then the oldest cycle(s) of data is excluded. Exclusion of 108 data points for the oldest 6 cycles results in 262 data points after 1R14. The 95 percent cumulative probability growth rate of 262 data points is 0.112 inch per EFPY. For conservatism, the growth rate value used in the operational assessment (OA) is 0.119 inch per EFPY at 604 degrees, which is consistent with the growth rate used in the prior cycle Unit 1 operational assessment.

1-3 PG&E Letter DCL-07-085 In support of growth rate evaluations and W* calculations, the actual length of Unit 1 Cycle 14 was 1.39 EFPY, and the projected length of Unit 1 Cycle 15 is 1.63 EFPY.

Cumulative number of indications detected in the tubesheet region as a function of elevation within the tubesheet.

Table 2 provides the cumulative number of indications detected in the tubesheet region as a function of elevation within the tubesheet. The table includes the distribution of Unit 1 indications before 1R14, the distribution of new 1R14 indications, updated Unit 1 distribution after 1R14, and the Unit 1 cumulative distribution and cumulative frequency after 1 R14. In 1 R14, two new indications were detected: one at 4.84 inch below the TTS (included in the minus 4 inch bin),

and one at 1.38 inch below the TTS (included in the minus 1 inch bin).

Condition monitoring [CM] and operational assessment [OA] main steamline break leak rate for each indication and each SG in accordance with the leak rate methodology described in PG&E Letter DCL-05-018, dated March 11, 2005, as supplemented by PG&E Letter DCL-05-090 dated August 25, 2005.

SLB Leak Rate for Detected Indications within 12 inches from TTS The CM and OA leak rates for axial PWSCC indications detected within 12 inches from the TTS are determined by using the constrained crack leak model. The 95 percent prediction bound leak rates for each indication, as well as each SG, are provided in Table 1 columns "CM Leak Rate" and "OA Leak Rate." The total CM SG leak rates are repeated in Table 3. The total OA SG leak rates are repeated in Table 4.

SLB Leak Rate for Undetected Indications within 12 inches from TTS The CM and OA leak rates for undetected indications between 8 and 12 inches below the TTS are determined by multiplying the number of undetected indications between 8 and 12 inches below the TTS by a factor of 0.0033 gallons per minute (gpm). The leak rate value of 0.0033 gpm is the 95 percent prediction bound leak rate, applying the constrained crack model with a Zone B1 contact pressure at a depth of eight inches below the TTS. For both CM and OA, eleven undetected indications are estimated between 8 and 12 inches below the TTS based on the more conservative of the 2 methods described below. Therefore, the CM and OA leak rates for undetected indications between eight and twelve inches below the TTS is 0.0363 gpm for each SG. These SG leak rates are repeated in Tables 3 and 4.

1-4 PG&E Letter DCL-07-085 Historical data projection method.

The number of undetected PWSCC indications between 8 and 12 inches below the TTS would not be expected to be much greater than the number reported between 4 and 8 inches below the TTS, due to the trend of decreasing number of indications with distance below the TTS.

Of the 39 historical PWSCC indications in DCPP Unit 1, 5 (13 percent) were between 4 to 8 inches below the TTS, and 6 (15 percent) were between 8 to 12 inches below the TTS. Therefore, for CM, 6 indications are assumed to be undetected at 1R14 between 8 and 12 inches below the TTS.

Figure 1 illustrates the cumulative number of PWSCC indications versus EFPY in DCPP Unit 1. A linear regression analysis using only data from the last six Unit 1 outages shows that about 44 cumulative indications are projected at EOC-1 5, about five new indications. Therefore, for OA, 7 indications (15 percent of 44) are assumed to be undetected at EOC-15 between 8 and 12 inches below the TTS.

Ninety percent probability prediction method.

Figure 2 presents a plot of the binned PWSCC elevation data for all DCPP Unit 1 historical indications located greater than 1 inch below the TTS. Excluding the expansion transition indications above 1 inch for Unit 1 would be expected to provide the best dataset for estimating indications at deeper depths. Figure 2 provides a best-fit regression of this data, an upper 90 percent probability prediction bound, and an upper 90 percent probability cumulative prediction bound. The number of indications that could be present in the range of 8 to 12 inches below the top of tubesheet is obtained by summing the upper 90 percent probability prediction bound individual values at 8, 9, 10, and 11 inches (approximately 2 to 3 in each bin),

for a total of about 11 indications. As a result, 11 indications will be applied for CM and OA because it is slightly greater than the 6 to 7 indications from the historical data projection method.

SLB Leak Rate for Indications Below 12 inches from TTS The CM and OA leak rates for indications located below 12 inches from the TTS are determined by the severed tube model. This model assumes all in-service tubes contain a 360 degree tube sever located 12 inches below the TTS and assigns a leak rate of 0.00009 gpm per tube. This value is the 90 percent prediction bound leak rate at 2560 pounds per square inch differential for a contact pressure representative of the 3 inch nominal crevice test specimen from the drilled hole crevice leak rate test data in WCAP-14797-P, Revision 2. The resulting CM and OA leak rates for each SG are listed in Tables 3 and 4, and are approximately 0.3 gpm for each SG.

1-5 PG&E Letter DCL-07-085

• Assessment of whether the results were consistent with expectations and, if not consistent, a description of the proposed corrective action.

The CM leak rates were consistent with expectations. Table 1 column "Prior OA Leak Rate" provides the prior cycle projected operational assessment leak rates for each repeat indication. This leak rate is compared to the CM leak rate under column "CM Leak Rate." For all repeat indications, the prior cycle OA leak rates are greater than or equal to the CM leak rates, and the "OA Underprediction" column reports no underpredictions.

The numbers and elevations of new PWSCC indications were consistent with expectations. Two new PWSCC indications were detected, which is less than the five new indications projected for EOC-14 based on a linear regression analysis using data from the five prior inspections. The elevations of the two new indications were about 1 and 4 inches below the TTS. Since about 72 percent of the PWSCC indications have been detected within about 4 inches from the TTS, the elevations of the new indications are consistent with expectations.

Technical Specification 5.6.10.d Reportinq Requirements DCPP TS 5.6.10.d requires that the aggregate calculated SLB leakage from application of all ARC and non-ARC be submitted within 90 days after the initial entry into MODE 4 following completion of an inspection performed in accordance with TS 5.5.9.

Table 5 (for CM) and Table 6 (for OA) report the calculated SLB leakage from application of each ARC in each SG, that is, W* ARC, Generic Letter 95-05 voltage-based ARC, and PWSCC ARC. SLB leakage from non-ARC degradation is also provided in these tables, and was determined to be 0 gpm. The ARC and non-ARC leak rates are then summed to arrive at an aggregate SLB leakage for each SG.

No in-situ leak testing of indications was performed in 1R14, so there is no SLB leakage contribution from in-situ testing.

In order to meet the accident-induced leakage performance criteria (AILPC), the aggregate calculated SLB leakage from application of all ARC.and non-ARC must not exceed 10.5 gpm (at room temperature) in the faulted SG for CM and OA. The 10.5 gpm limit was approved by the NRC in License Amendment (LA) 156/156. The aggregate calculated CM SLB leakage at EOC-14 is 0.95 gpm for the limiting SG (SG 1-1) as shown in Table 5. The aggregate calculated operational assessment SLB leakage at EOC-15 is 3.07 gpm for the limiting SG (SG 1-2) as shown in Table 6. In both assessments, SLB leakage is less than the allowable limit. Therefore, the AILPC has been satisfied for CM at EOC-14 and OA at EOC-15.

1-6 PG&E Letter DCL-07-085 Table 1 1R14 Indications in Hot Leg WEXTEX Tubesheet Region (Excluding Circumferential Indications)

Tube Crack Crack Total Dist UCT UCT below W*

Dist UCT UCT SG Count Row Col Radial Ind Volts ID/ODCra CAL LCT UCT Length Length to TTS TTS BwLength to BWT W

Position 11 1

2 41 9.02 SAI 0.49 ID 1

21

-1.38

-1.27 0.11 0.11 60 1.05 Yes B1 7.12

-0.20 0.79 No 11 2

3 2

58.49 SAI 0.85 ID 1

21

-1.33

-1.08 0.25 0.25 60 0.86 Yes A

5.32

-0.09 0.71 No 11 3

15 10 52.09 SAI 0.84 ID 1

21

-9.22

-9.06 0.16 0.34 39 8.84 Yes A

5.32

-0.26 8.52 Yes 11 4

15 10 52.09 SAI 1.5 ID 2

21

-8.72

-8.54 0.18 0.34 54 8.32 Yes A

5.32

-0.26 8.00 Yes 11 5

20 44 26.91 SAI 0.67 ID 1

21

-8.7

-8.6 0.1 0.1 31 8.38 Yes B2 7.12

-1.85 6.47 No 12 1

1 87 50.65 SAI 3.38 ID 1

36

-10.03

-9.66 0.37 0.37 64 9.44 Yes A

5.32

-0.28 9.10 Yes 12 2

2 9

49.45 SAI 0.48 ID 1

21

-1.60

-1.38 0.22 0.22 54 1.16 Yes A

5.32

-0.34 0.76 No 12 3

7 33 21.04 SAI 2.14 ID 1

36

-2.15

-1.72 0.43 0.43 93 1.50 Yes B2 7.12

-0.35 1.09 No 12 4

20 37 29.75 SAl 2.56 ID 1

36

-1.86

-1.62 0.24 0.24 70 1.40 Yes B3 7.12

-0.13 1.21 No 13 1

10 20 37.81 SAI 0.34 ID 1

25

-2.31

-2.19 0.12 0.12 20 1.97 Yes B4 7.12

-0.11 1.80 No 13 2

30 45 39.47 SAI 0.32 ID 1

25

-2.22

-2.13 0.09 0.09 20 1.91 Yes B4 7.12

-0.19 1.66 No 13 3

31 36 43.21 SAI 0.44 ID 1

25

-2.88

-2.76 0.12 0.12 20 2.54 Yes A

5.32

-0.21 2.27 No 13 4

33 37 45.23 SAl 0.43 ID 1

25

-5.83

-5.71 0.12 0.12 20 5.49 Yes A

5.32

-0.40 5.03 No 13 5

39 46 50.91 SAI 0.7 ID 1

25

-2.74

-2.59 0.15 0.15 20 2.37 Yes A

5.32

-0.25 2.06 No 14 1

23 7

60.12 SAI 0.47 ID 1

39

-8.20

-8.05 0.15 0.28 20 7.83 Yes A

5.32

-0.19 7.58 Yes 14 2

23 7

60.12 SAI 0.46 ID 2

39

-5.08

-4.95 0.13 0.28 20 4.73 Yes A

5.32

-0.19 4.48 No 14 3

28 57 38.74 SAI 0.26 ID 1

16

-2.79

-2.66 0.13 0.26 20 2.44 Yes B4 7.12

-0.33 2.05 No 14 4

28 57 38.74 SAI 0.34 ID 2

16

-6.55

-6.42 0.13 0.26 20 6.20 Yes B4 7.12

-0.33 5.81 No 14 5

35 33 49.38 SAI 0.42 ID 1

25

-4.95

-4.84 0.11 0.11 20 4.62 Yes A

5.32

-0.16 4.40 No 14 6

39 58 52.62 SAI 0.42 ID 1

39

-6.09

-5.91 0.18 0.18 20 5.69 Yes A

5.32

-0.04 5.59 Yes 1-7 PG&E Letter DCL-07-085 Table 1 (continued) 1R14 Indications in Hot Leg WEXTEX Tubesheet Region (Excluding Circumferential Indications)

Cot RowClBelow Dist EOC (N+1)

Dist Ispec Flex W*

Insp Ext Prior OA OA Under CM Leak OA Leak PREVW*

Tube SG Count Row Col Below Dsto E

)

(N+11) UCT UCT Below W*Cand Extent Ext wrt Length Satisfied ? Leak Rate Prediction rate Rate TubePlugged BWT?

to BWT BWT?

BWT 11 1

2 41 Yes 0.86 0.60 Yes Yes

-9.57 9.28 7.28 Yes 0.308 No 0.283 0.325 Yes No 11 2

3 2

Yes 0.67 0.52 Yes Yes

-9.66 9.48 5.62 Yes 0.005 No 0.005 0.005 Yes No 11 3

15 10 Yes 8.65 8.33 Yes Yes

-11.26 10.91 5.32 Yes 0.001 No 0.001 0.001 Yes No 11 4

15 10 Yes 8.13 7.81 Yes Yes

-11.26 10.91 5.32 Yes 0.001 No 0.001 0.001 Yes No 11 5

20 44 Yes 8.19 6.28 Yes Yes

-11.40 9.46 7.27 Yes 0.003 No 0.002 0.002 Yes No 1

0.318 1

1 0.293 1 0.335 1

12 1

1 87 Yes 9.25 8.91 Yes Yes

-11.91 11.54 5.32 Yes 0.001 No 0.001 0.001 Yes No 12 2

2 9

Yes 0.97 0.57 Yes Yes

-9.40 8.97 5.59 Yes NA 0.014 0.015 No 12 3

7 33 Yes 1.31 0.90 Yes Yes

-9.03 8.59 7.60 Yes 0.150 No 0.127 0.144 Yes Yes No 12 4

20 37 Yes 1.21 1.02 Yes Yes

-8.61 8.39 7.41 Yes 0.091 No 0.077 0.086 Yes Yes No 1

0.242 0.219 0.245 1

13 1

10 20 Yes 1.78 1.61 Yes Yes

-8.39 8.19 7.29 Yes 0.033 No 0.031 0.034 Yes No 13 2

30 45 Yes 1.72 1.47 Yes Yes

-9.76 9.48 7.26 Yes 0.029 No 0.027 0.030 Yes No 13 3

31 36 Yes 2.35 2.08 Yes Yes

-8.40 8.10 5.49 Yes 0.016 No 0.015 0.016 Yes No 13 4

33 37 Yes 5.30 4.84 Yes Yes

-8.84 8.35 5.49 Yes 0.005 No 0.004 0.005 Yes No 13 5

39 46 Yes 2.18 1.87 Yes Yes

-9.36 9.02 5.52 Yes 0.008 No 0.008 0.008 Yes No S0.091 1 0.085 0.093 1

14 1

23 7

Yes 7.64 7.39 Yes Yes

-9.15 8.87 5.32 Yes 0.001 No 0.001 0.001 Yes No 14 2

23 7

Yes 4.54 4.29 Yes Yes

-9.15 8.87 5.71 Yes 0.002 No 0.002 0.002 Yes No 14 3

28 57 Yes 2.25 1.86 Yes Yes

-8.50 8.08 7.43 Yes 0.023 No 0.023 0.025 Yes No 14 4

28 57 Yes 6.01 5.62 Yes Yes

-8.50 8.08 7.49 Yes 0.004 No 0.004 0.005 Yes No 14 5

35 33 Yes 4.43 4.21 Yes Yes

-8.24 7.99 5.48 Yes NA 0.004 0.005 No 14 6

39 58 Yes 5.50 5.40 Yes Yes

-9.08 8.95 5.32 Yes 0.003 No 0.003 0.003 Yes Yes No 10.033 0.037 0.0401 1-8 PG&E Letter DCL-07-085 Column - Table 1 Legend and Notes for Table 1 SG Steam generator Count Indication count per SG Row Tube Row Col Tube Column Tube Radial Position Tube radial position, inch.

Ind Indication of degradation. SAI means single axial indication.

Volts Peak voltage from Plus Point coil ID/OD Tube surface, either inside diameter (ID) or outside diameter (OD)

Crack #

Crack number CAL Plus Point calibration group number LCT Elevation (inch) of lower crack tip (LCT), relative to the top of tubesheet (TTS).

UCT Elevation (inch) of upper crack tip (UCT), relative to the TTS.

Crack Length Length of crack (inch)

Total Length Total length of all cracks (inch).

MD-adj Maximum depth (% through-wall) from Plus Point coil. The depth is the adjusted depth using the same techniques as PWSCC ARC depth sizing.

Dist UCT to TTS Distance (inch) between the UCT and TTS, including ANDECT-TTS (Plus Point NDE uncertainty on locating the crack tip relative to the TTS).

UCT below TTS?

If the UCT (including NDE uncertainty) is located below TTS (i.e., a positive number in the "Dist UCT to TTS" column), then "yes" is indicated (information only).

W* ZONE W* tubesheet zone based on crack location.

W* Length W* length is 7.12 inch for hot leg Zone B and 5.32 inch for hot leg Zone A, and includes ANDEw (NDE uncertainty in measuring the W* depth).

BWT Elevation of the bottom of the WEXTEX transition (BWT), inch, measured by bobbin relative to the TTS.

Dist UCT to BWT Distance (inch) between the UCT and BWT, including ANDEcT-BWT (PlUs Point NDE uncertainty on locating the crack tip relative to the BWT).

UCT Below W*?

If the UCT is located below the W* length, then the tube is a W* tube. Any type of degradation below the W* length is acceptable.

UCT Below BWT?

If the UCT is located below BWT, then the tube is a W* candidate, and performance monitoring is satisfied for repeat indications.

Dist EOC (N+1) UCT to TTS Distance (inch) between the UCT and TTS at the end of the next cycle including ANDECT-TTS, based on growing the UCT at 0.119 inch/EFPY.

Dist EOC (N+1) UCT to BWT Distance (inch) between the UCT and BWT at the end of the next cycle including ANDECT-BWT, based on growing the UCT at 0.119 inch/EFPY.

EOC (N+1) UCT below If the UCT (including NDE uncertainty) is located below BWT at the end of the next cycle (i.e., a positive number in the "Dist UCT (n+1) UCT to BWT" column), the tube is BWT?

a W* candidate.

W* Cand?

W* candidate, also referred to as W* tube. A tube is a W* candidate (or W* tube) if the UCT is below BWT and the EOC (n+l) UCT is below BWT.

Inspect Extent Elevation of Plus Point inspection relative to TTS (inch).

W* inspection extent with respect to BWT, also referred to as the W* inspection distance (inch). This is the Plus Point inspection extent relative to BWT. The W*

W* Insp Ext wrt BWT inspection distance below BWT is equal to the Plus Point inspection extent below TTS, plus measured distance from BWT to TTS, plus bobbin NDE uncertainty in locating BWT relative to TTS.

Flexible W* length relative to BWT (inch), equal to W* Length + 'Clj (total axial crack length) + NCL*ANDECL (number of indications times Plus Point NDE uncertainty with Flex W* Length measuring length of axial cracks) + NCL*ACG (number of indications times crack growth, 0.119 inch/EFPY)

Insp Ext Satisfied?

If the W* inspection distance is greater than or equal to the flexible W* length, then the inspection extent is satisfied.

Prior OA Leak Rate Prior cycle projected operational assessment (OA) leak rate, gpm at room temperature, using Constrained Crack leak model.

OA Underprediction?

If the CM leak rate is greater than the prior cycle OA projected leak rate, then the OA would be underpredicted.

CM Leak Rate Condition monitoring (CM) SLB leak rate, gpm at room temperature, using Constrained Crack leak model, based on distance of UCT to TTS. No SLB leak rate is assigned to indications with UCT located below TTS minus 12 inches.

OA Leak Rate Operational assessment (OA) SLB leak rate, gpm at room temperature, using Constrained Crack leak model, based on distance of EOC (n+l) UCT to TTS. No SLB leak rate is assigned to indications with EOC (n+l) UCT located below TTS minus 12 inches.

PREVW* Tube?

Previous W* Tube. If the indication was left in service in the prior cycle, it is classified as a previous W* tube (i.e., a repeat indication). Otherwise, the indication is new.

Deplugged?

If tube was de-plugged during a previous outage, then "yes" is indicated.

Tube Plugged?

If tube was plugged during the current outage, then "yes" is indicated.

1-9 PG&E Letter DCL-07-085 Table 2 Cumulative Number of Unit 1 PWSCC Indications Detected in the Tubesheet Region as a Function of Tubesheet Elevation Distribution of Cumulative Cumulative Distance (inch)

Distribution Pre New Distribution Distribution Frequency relative to TTS 1R14 Indications in Post 1 R14 Post 1R13 Post 1R13 1R14

-12 0

0 0

0.00

-11 0

0 0

0.00

-10 0

0 0

0.00

-9 2

2 2

0.05

-8 4

4 6

0.15

-7 0

0 6

0.15

-6 2

2 8

0.21

-5 1

1 9

0.23

-4 1

1 2

11 0.28

-3 2

2 13 0.33

-2 6

6 19 0.49

-1 6

1 7

26 0.67 0

13 13 39 1.00 1

0 0

39 1.00 Total 37 2

39 39 1-10 PG&E Letter DCL-07-085 Table 3 DCPP Unit 1 Condition Monitoring Steam Line Break Leak Rates for W* Alternate Repair Criteria EOC-14 Condition Monitoring Leak Rate SG1-1 SG1-2 SG1-3 SG1-4 (gpm at room temperature)

I I

I_

I Detected indications within TTS minus 12 inches 0.293 0.219 0.085 0.037 Undetected indications within 8 to 12 inches below TTS 0.0363 0.0363 0.0363 0.0363 Undetected indications below TTS minus 12 inches (Note 1) 0.28 0.28 0.30 0.29 Total 0.61 0.54 0.42 0.36 Note 1: Leak rates are based on 0.00009 gpm multiplied by the number of inservice tubes in Cycle 14 Table 4 DCPP Unit 1 Operational Assessment Steam Line Break Leak Rates for W* Alternate Repair Criteria EOC-15 Operational Assessment Leak Rate SG1-1 SG1-2 SG1-3 SG1-4 (gpm at room temperature)

I I

I I

Detected indications within TTS minus 12 inches 0.335 0.245 0.093 0.040 Undetected indications within 8 to 12 inches below TTS 0.0363 0.0363 0.0363 0.0363 Undetected indications below TTS minus 12 inches (Note 1) 0.28 0.27 0.30 0.29 Total 0.65 0.55 0.43 0.37 Note 1: Leak rates are based on 0.00009 gpm multiplied by the number of inservice tubes in Cycle 15.

Table 5 DCPP Unit I Aggregate Condition Monitoring Steam Line Break Leak Rates EOC-14 Condition Monitoring Leak Rate SG 1-1 JSG 1-2 ISG 1-3 JSG 1-4 (gpm at room temperature)

I II W* ARC 0.609 0.535 0.421 0.363 Voltage-Based ARC (Note 1) 0.34 0.19 0.10 0.06 PWSCC ARC (Note 2) 0 0

0 0

Non-ARC degradation 0

0 0

0 Aggregate 0.95 0.73 0.52 0.42 Note 1: Voltage-based ARC leak rates are described in Enclosure 3.

Note 2: PWSCC ARC leak rates are described in Enclosure 2.

. Table 6 DCPP Unit 1 Aaareaate Operational Assessment Steam Line Break Leak Rates EOC-15 Operational Assessment Leak Rate SG1-1 SG1-2 SG 1-3 TSG1-4 (gpm at room temperature)

I 1-1 I

SG_1-4 W* ARC 0.651 0.551 0.429 0.366 Voltage-Based ARC (Note 1) 0.68 0.38 0.20 0.16 PWSCC ARC (Note 2) 0 2.14 0

0 Non-ARC degradation 0

0 0

0 Aggregate 1.33 3.07 0.63 0.53 Note 1: Voltage-based ARC leak rates are described in Enclosure 3.

Note 2: PWSCC ARC leak rates are described in Enclosure 2.

1-11 PG&E Letter DCL-07-085 Figure 1 DCPP I Cumulative Tubesheet Region PWSCC Trending by EFPY Through 1R14 All Data 0

Post-W* Outages -

- - IRI5 Linear (Post-W* Outages) 50 45 40-352.95-4.94 30

0 25 2

S20 UI 15 -

0 1

5 0

.h 0

5 10 15 20 25 EFPY 1-12

DCPP Unit I Tubesheet PW 30 I

U Data 1 Inch and Greater Below Regression 25 Upper 90% Prediction Cum. Pred. Bound Indications 20-1 0 E

5 ii E

z 10-_

N 5

0 PG&E Letter DCL-07-085 Figure 2

'SCC Elevation vs. Number of Indications 70 TTS 60 50

-- 40 30 E 20 10 ILI 6

7 8

9 10 11 12 ce below TTS (inch) 1-13 0

1 2

3 4

5 Distan PG&E Letter DCL-07-085 ENCLOSURE 2 TSP PWSCC ALTERNATE REPAIR CRITERIA 120-DAY REPORT DIABLO CANYON POWER PLANT UNIT 1 FOURTEENTH REFUELING OUTAGE NRC Reportinq Requirements Primary water stress corrosion cracking (PWSCC) alternate repair criteria (ARC) for axial PWSCC at dented tube support plates (TSP) was implemented for the fourth time in Diablo Canyon Power Plant (DCPP) Unit 1 during the Unit 1 Fourteenth Refueling Outage (1R14). 1R14 steam generator (SG) inspections and repairs were completed in May 2007.

For implementation of ARC for axial PWSCC at dented TSPs, DCPP TS 5.6.1 0.f requires that the results of the condition monitoring (CM) and operational assessments (OA) be submitted within 120 days after initial entry into MODE 4 following completion of an inspection performed in accordance with TS 5.5.9. This report implements the DCPP technical specification (TS) reporting criteria.

To satisfy the TS, this report includes the following:

" Tabulations of indications found in the inspection, tubes repaired, and tubes left in service under the ARC.

Growth rate distributions for indications found in the inspection and growth rate distributions used to establish the tube repair limits.

" Plus Point confirmation rates for bobbin detected indications when bobbin is relied upon for detection of axial PWSCC in less than or equal to 2 volt dents.

" For CM, an evaluation of any indications that satisfy burst margin requirements based on the Westinghouse burst pressure model, but do not satisfy burst margin requirements based on the combined Argonne National Laboratory (ANL) ligament tearing and EPRI through-wall (ANL/TW) burst pressure model.

" Performance evaluation of the OA methodology for prediction of flaw distributions as a function of flaw size.

Evaluation results Of number and size of previously reported versus new PWSCC indications found in the inspection, and the potential need to account for new indications in the OA burst evaluation.

" Identification of mixed mode (axial PWSCC and circumferential) indications found in the inspection and an evaluation of the mixed mode indications for potential impact on the axial indication burst pressures or leakage. In addition, as committed in Pacific Gas and Electric Company (PG&E) Letter DCL-02-045, Response to Final NRC Request for Additional Information Regarding Supplement 3 to License Amendment Request 00-06, "Alternate Repair Criteria for Axial PWSCC at Dented Intersections in Steam Generator Tubing," dated April 18, 2002, performance of a 2-1 PG&E Letter DCL-07-085 trending analysis to assess the potential for increasing mixed mode affects over time.

Any corrective actions found necessary in the event that CM requirements are not met.

Back-ground: Dented TSP Plus Point Inspection Scope The 1 R14 Plus Point dent inspection scope for greater than 2 volt dents was based on greater than 2 volt dents called in the prior Unit 1 Thirteenth Refueling Outage (1 R1 3).

The minimum scope for greater than 2 volt dents inspected by Plus Point in 1 R14 is provided in Table 1.

The dented TSP inspection criteria and expansion plan criteria described below are based on PG&E Letter DCL-01-036, "Revision of Dent Inspection Program Requirements," dated April 16, 2001, and WCAP-15573, Revision 1, "Depth-Based SG Tube Repair Criteria for Axial PWSCC at Dented TSP Intersections - Alternate Burst Pressure Calculation."

Plus Point inspection criteria for axial PWSCC left in service Plus Point inspections shall be conducted on 100 percent of axial PWSCC indications at dented TSP intersections that were left in service in Unit 1 Cycle 14. Two hundred nineteen axial PWSCC indications had been left in service in Cycle 14 under PWSCC ARC.

Plus Point inspection criteria for greater than or equal to () 2 volt dented intersections On a SG-specific basis, Plus Point inspections shall be conducted on 100 percent of > 5 volt dented intersections up to and including the coldest TSP elevation where PWSCC (at any size dent), circumferential indications (at any size dent), or axial outside diameter stress corrosion cracking (ODSCC) not detected by bobbin (AONDB)

(at > 5 volt dent) have been previously detected in that SG in the prior two outages, or current outage (expansion required), plus 20 percent of > 5 volt dents at the next colder TSP elevation. In each SG where 100 percent hot leg TSP Plus Point inspections are not required, Plus Point inspections shall be conducted on 20 percent of > 5 volt dents at each hot leg TSP. For any 20 percent sample, a minimum of 50 > 5 volt dents shall be inspected. If the population of > 5 volt dents at that TSP elevation is less than 50, then 100 percent of the > 5 volt dents at that TSP shall be inspected.

On a SG-specific basis, Plus Point inspections shall be conducted on 100 percent of greater than (>) 2 and less than (<) 5 volt dented intersections up to and including the coldest TSP elevation where PWSCC (at any size dent), circumferential indications (at any size dent), or > 2 inferred volt AONDB (at > 2 and < 5 volt dent) have been previously detected in that SG in the prior two outages, or current outage (expansion required), plus 20 percent of > 2 and < 5 volt dent at the next colder TSP elevation. If a 2-2 PG&E Letter DCL-07-085 SG is free from PWSCC (at any size dent), circumferential indications (at any size dent) and > 2 inferred volt AONDB (at > 2 and < 5 volt dent), then Plus Point inspections shall be conducted on 20 percent of > 2 and < 5 volt dents at 1 H. For any 20 percent sample, a minimum of 50 > 2 and < 5 volt dents shall be inspected. If the population of > 2 and < 5 volt dents at that TSP elevation is less than 50, then 100 percent of the > 2 and < 5 volt dents at that TSP shall be inspected.

The coldest TSP where PWSCC, AONDB with > 5 volt dent, or circumferential indications have been found in the prior two outages (Unit 1 Twelfth Refueling Outage

[1R12] and 1R13) was 4H for SG 1-1, 7C for SG 1-2, and 6H for SG 1-4. In SG 1-3, no PWSCC, AONDB with > 5 volt dent, or circumferential indications have been detected.

In addition, all inferred bobbin voltages for AONDB indications have been less than 2 volts, so AONDB indications are not a factor in the inspection criteria Plus Point inspection criteria for detection of circumferential indications at dents On a SG-specific basis, if a circumferential indication or > 2 inferred volt AONDB is detected in a dent of "x" volts in the prior two outages, or current outage (expansion required), then Plus Point inspections shall be conducted on 100 percent of dents greater than "x - 0.3" volts up to the affected TSP, plus 20 percent of dents greater than "x - 0.3" volts at the next higher TSP. "X" is defined as the lowest dent voltage where a circumferential crack or > 2 inferred volt AONDB was detected in that SG. For any 20 percent sample, a minimum of 50 "x - 0.3" volt dents shall be inspected. If the population of "x - 0.3" volt dents at that TSP elevation is less than 50, then 100 percent of the "x - 0.3" volt dents at that TSP shall be inspected.

In SG 1-1, the smallest dent in which a circumferential crack has been detected in the prior two outages (1 R1 2 and 1 R1 3) was 0.51 volts (in 1 R1 2 at 1 H). Thus, in 1 R1 4, 100 percent of dents greater than 0.21 volts (i.e., 0.51 -0.3 = 0.21)were required to be Plus Point inspected in SG 1-1 at 1H, and 20 percent at 2H. Because there are no dents less than 0.21 volts at 1H in SG 1-1, the actual SG 1-1 Plus Point inspection plan became 100 percent of less than or equal to (<) 2 volt dents at 1 H, and 20 percent at 2H.

In SG 1-3, no circumferential cracking has ever been detected. In SG 1-2 and SG 1-4, the smallest dents in which a circumferential crack has been detected in the prior two outages (1 R12 and 1 R13) are 3.13 volts and 14.89 volts, respectively. Since these dent voltages are much greater than the 2.3 volt dent threshold for inspection, less than 2 volt dent Plus Point inspections were not required in the inspection plans in these SGs, along with SG 1-3.

Summary of Plus Point inspection plan of dented TSPs Based on the Plus Point inspection criteria listed above, the following Plus Point dent inspection criteria were implemented. The numbers of dent inspections is summarized in Table 1.

2-3 PG&E Letter DCL-07-085

" SG 1-1:

100% of < 2 volt dents at1H, 20%at2H 100% of > 2 and < 5 volt dents from I H to 4H, 20% at 5H 100% of -> 5 volt dents from 1 H to 4H, 20% from 5H to 7H

" SG 1-2:

100% of > 2 and < 5 volt dents from 1H to 7C, 20% at 6C 100% of 2 5 volt dents from 1 H to 7C, 20% at 6C

" SG1-3:

20% of>2and<5voltdentsatlH 20% of > 5 volt dents from 1 H to 7H SG 1-4:

100% of > 2 and < 5 volt dents from IH to 6H, 20% at 7H 100% of > 5 volt dents from 1 H to 6H, 20% at 7H All 20 percent samples shall contain a minimum of 50 dents. If the population of dents at the TSP elevation is less than 50, then inspect 100 percent of the dents at the TSP.

Plus Point inspection of bobbin distorted indications at less than or equal to 2 volt dents One hundred percent of the tubes were inspected by bobbin coil, and the bobbin coil was relied upon for detection of axial PWSCC in < 2 volt dents. If the bobbin coil detected a distorted inside diameter support signal (DIS) at a dented TSP intersection, then Plus Point inspection was performed.

Summary of Inspection Results Table 5 provides a list of all TSP axial PWSCC indications detected in 1 R14. Table 7 provides a list of all TSP circumferential indications detected in 1 R14.

Expansion of the Plus Point dent inspection program was required in SG 1-1 in 1R14, based on detection of axial PWSCC at R19C15 7C dented TSP (1.26 volt dent). The indication was detected by bobbin and confirmed by Plus Point. The required expansion was 100 percent of >2 volt dents from 5H to 7C, and 20 percent at 6C. The actual expanded scope was more conservative and included 100 percent of >2 volt dents in the cold leg. No additional indications were detected in this expanded program.

In SG 1-3, preliminary disposition of a Plus Point signal at a 7C TSP was initially attributed to axial PWSCC, which initiated a Plus Point expansion program. However, final disposition of the signal was no detectable degradation (NDD) based on tracing the bobbin signal to the baseline inspection. One hundred percent of >2 volt cold leg dents (103 cold leg dents) and 33 percent of >2 volt hot leg dents that were not originally planned for inspection (140 hot leg dents) were inspected as part of expanded scope prior to termination of the expansion program. No indications were detected.

2-4 PG&E Letter DCL-07-085 No additional expansions of the Plus Point dent inspection program were required, based on no observations of axial PWSCC, AONDB with > 5 volt dent, or circumferential indications at TSP elevations higher than the defined critical areas. All inferred bobbin voltages for AONDB indications were less than 2 volts. The dent voltages associated with TSP circumferential indications were greater than or equal to 4.95 volts, higher than the 2.3 volt dent threshold for potential expansion.

Tabulations of indications found in the inspection, tubes repaired, and tubes left in service under the ARC.

Two hundred thirty five (235) axial PWSCC indications at dented TSP intersections were detected in 1 R14. Table 5 provides a tabulation of indications, including the following information:

" SG, row, column, TSP, crack number, calibration group number Identifies the indication as repeat or new.

For indications that were plugged in 1 R14, the reason for plugging.

Adjusted nondestructive examination (NDE) measurements (length, maximum depth, and average depth), voltage, and adjusted NDE crack location relative to the TSP centerline.

Burst pressures (free span and total length). For the operational assessment, the pressures are calculated using the ANL/TW burst model. For the CM assessment, the pressures are calculated using the Westinghouse burst model. A burst pressure of 6100 pounds per square inch (psi) represents a predicted burst pressure

>2 6100 psi since all pressures predicted to exceed 6100 psi are grouped at 6100 psi to reduce computer storage requirements in the analysis.

" Steam line break (SLB) leak rates (free span and total length) using the ANL ligament tearing model, for CM and OA.

The PWSCC ARC allows axial PWSCC indications to remain in service at dented TSP intersections if the following PWSCC ARC conditions are satisfied for each indication:

" OA free span burst pressure (based on the ANL/TW model) exceeds 3APNO. The 3APNO burst pressure is equal to 4419 psi.

OA total length burst pressure (based on the ANL/TW model) exceeds 1.4APSLB.

The 1.4APSLB burst pressure is equal to 3367 psi, based on a APSLB of 2405 psi (pressurizer power operated relief valve (PORV) setpoint plus uncertainty).

OA free span leak rate, when combined with free span leak rates from other degradation mechanisms, is less than 0.54 gpm at room temperature in a faulted SG.

OA total length leak rate, when combined with leak rates from other degradation mechanisms, is less than 10.5 gallons per minute (gpm) (room temperature) in a faulted SG.

2-5 PG&E Letter DCL-07-085 The indication is less than 40 percent through-wall outside the TSP crevice.

In addition to the above PWSCC ARC conditions, axial PWSCC indications must satisfy the following exclusion criteria in order to remain in service:

" The indication is not located at a TSP intersection located in the wedge region or 7H/7C high bending stress region.

The indication is not located at a TSP intersection that contains cracked or missing TSP ligaments.

" The indication is not located at a TSP intersection that contains a different degradation mechanism.

The indication is not located in a tube that contains another repairable indication.

Two hundred eighteen (218) axial PWSCC indications at dented TSPs had been returned to service in 1 R13 under PWSCC ARC. 1 R13 indication at SG 1-2 R25C79 TSP 2H was subsequently re-evaluated and determined that there were two separate indications in 1R13 (crack 1 and 2), consistent with 1R14 results. Therefore, 219 axial PWSCC indications had been returned to service in Cycle 14. Two of the repeat indications were merged into a single indication in Cycle 14 (SG 1-2 R8C61 crack 1).

Following 1R14 Plus Point inspection, sizing, and application of PWSCC ARC requirements, ten of these repeat indications were plugged, as described below, and all others were allowed to remain in service under PWSCC ARC.

Two due to inside diameter or outside diameter (ID/OD) indications at the same TSP.

Two preventively plugged with the lowest axial PWSCC projected OA burst pressures at the end of the next cycle, even though burst pressure margins were satisfied. Each of these locations had an additional PWSCC indication, so the number of indications plugged was four.

" Four due to pluggable degradation at a different tube location.

In 1R14, 17 new axial PWSCC indications at dented TSPs were detected (two of which were at a TSP with an additional repeat indication), sized by Plus Point, and applied to PWSCC ARC requirements. One of these were plugged due to ID/OD degradation, and one was plugged due to the axial PWSCC indication being greater than or equal to 40 percent depth outside the tube support plate (as indicated by "DOP > 40%" in Table 5).

The indications that were located outside the TSP region were reviewed to determine the need for in-situ pressure testing in accordance with the criteria in WCAP-1 5573, Revision 1. Namely, if CM for axial PWSCC at dented TSPs predicts free span leakage or free span burst pressures less than 3APNO, then in-situ pressure testing is required.

These conditions were not predicted by CM, and therefore no in-situ pressure testing of axial PWSCC at dents was required nor performed.

2-6 PG&E Letter DCL-07-085 Two hundred twenty three (223) axial PWSCC indications at dented TSPs were returned to service in 1R14: 208 repeat indications and 15 new indications.

Growth rate distributions for indications used to establish the tube repair limits and for indications found in the inspection The growth rate distribution used to establish the tube repair limits was based on prior outage growth data. The methodology for establishing the growth rate was established in WCAP-1 5573, Revision 1, as further explained in PG&E Letters DCL-02-023 and DCL-02-045. The methodology is summarized below:

" If there are at least 200 points in each of the last 2 cycles on the unit being inspected, the most conservative growth distribution from the last 2 cycles shall be used.

" If there are at least 200 points over the last 2 cycles on the unit being inspected, the growth distribution to be used is the more conservative of the combined data or either of the 2 cycles.

" If there are less than 200 points over the last 2 cycles on the unit being inspected, the growth distribution to be used shall contain data from both units over the last 2 (or 3 if necessary) cycles of each unit until 200 data points are obtained. The data from each cycle is compared for consistency in growth magnitude. If a given cycle has lower growth rates than other cycles, it is not included in the growth distribution.

In preparation for 1 R14, the first bullet applied. As shown in Table 2, the number of growth rate data points in Cycle 12 and Cycle 13 are 215 and 226, respectively, such that there are over 200 points in each of the last 2 cycles. Because there are a total of at least 200 points over the last 2 cycles on Unit 1, all other prior cycle growth rates did not require consideration. The Cycle 13 Cumulative Probability Distribution (CPD) growth rates are more conservative than Cycle 12 for length, and are also more conservative for maximum depth and average depth in all bins except for the upper tails. To bound the ARC method, for the preliminary EOC-1 5 OA, PG&E chose to conservatively use the lower bound CPD growth rates between Cycle 12 and Cycle 13.

The lower bound growth rate CPD is provided in Table 1 and was used in the Monte Carlo preliminary EOC-1 5 OA calculations for determining the need for tube repair.

In accordance with WCAP-1 5573, Revision 1, Unit 1 Cycle 14 growth rates that could impact the upper tail of the preliminary OA growth distribution were evaluated during 1 R14. The methodology requires that if new growth data causes the growth distribution above 90 percent probability to be more conservative, the new data should be added to the growth distribution for the final OA.

Two hundred twenty four (224) additional growth rate data points from Cycle 14 were established, 217 from repeat indications and 7 from new indications. Cycle 14 repeat indication growth rates are provided in Table 6, and the CPD of the Cycle 14 repeat plus new growth data is provided in Table 2.

2-7 PG&E Letter DCL-07-085 In support of growth rate evaluations and OA, the actual length of Unit 1 Cycle 14 was 1.39 EFPY and the projected length of Unit 1 Cycle 15 is 1.63 EFPY.

The Cycle 14 growth rates were compared to the 90 percentile growth rates used in the preliminary EOC-15 OA (0.069 inch, 9.6 percent maximum depth [MD], 6.9 percent average depth [AD]). Several Cycle 14 growth rates exceeded these values, and the WCAP methodology required that these Cycle 14 data points be added to the growth distribution for the final OA. To satisfy this method requirement, PG&E compared the growth rate CPD values from Cycle 14 to the growth rate CPD values used in the preliminary OA, and determined that the preliminary OA CPDs were equal to or bounding in all bins for length, maximum depth, and average depth, except for the 0 percent and 0.08 percent bins for average depth. For these two bins, the Cycle 14 CPD values were used in the Monte Carlo final EOC-1 5 OA calculations for determining the need for tube repair, as shown in Table 2. For information, Table 3 compares the 90 and 95 percentile growth values per EFPY at 604 degrees for Cycles 11 through 14.

Consistent with past practices, the merged indication (SG 1-2 R8C61 crack 1) was not included in the growth rate evaluations because two indications in 1 R1 3 merged into one indication in 1R14. The length and maximum voltage of the 1R14 indication was 0.59 inch and 1.81 volts, which were not significantly larger than the combined length (0.55 inch) and maximum voltage (1.53 volts) of the two 1R13 indications. Thus, these indications did not undergo significant growth in length and depth.

As noted above, several Cycle 14 depth growth rates were in the upper tail of the growth distribution. Most of these were associated with a maximum voltage increase from less than or equal tool volt in 1 R1 3 to greater than 1 volt in 1 R14. As discussed in PG&E Letter DCL-06-029, "Special Report 06 Results of Steam Generator (SG)

Tube Inspections for Diablo Canyon Power Plant Unit 1 Thirteenth Refueling Outage,"

dated February 24, 2006, in accordance with PWSCC ARC methods, the maximum depth for an indication less than or equal to 1 volt is determined by the depth from phase angle analysis at maximum volts (likely most reliable depth for low voltage indications) with a minimum of 20 percent, and the maximum depth for an indication greater than 1 volt is determined by direct phase angle analysis even though the location of maximum depth may not be at the location of maximum volts. This difference in sizing techniques for low voltage indications can lead to increased growth estimates. For conservatism, all of these data points were included in the final growth distribution for the OA.

Plus Point confirmation rates for bobbin detected indications when bobbin is relied upon for detection of axial PWSCC in less than or equal to 2 volt dents.

In 1 R14, the bobbin coil was relied upon for detection of axial PWSCC in less than or equal to 2 volt dents. As identified in Table 4, there were 132 DIS indications detected by bobbin at TSP intersections with nonrepeat PWSCC indications. Tracking of Plus 2-8 PG&E Letter DCL-07-085 Point confirmation rates for repeat PWSCC indications tubes is not required because these known flaws are inspected by Plus Point regardless of the bobbin call.

All DIS indications were inspected by Plus Point. Only 8 of the 132 DIS indications were confirmed as PWSCC by Plus Point, for a Plus Point confirmation rate of about 6 percent, or a 94 percent bobbin overcall rate. Each SG exceeded the approximately 90 percent overall rate generated during the bobbin coil performance test documented in WCAP-1 5573, Revision 1. The high bobbin overcall rate establishes a very high probability of detecting significant axial PWSCC indications in less than or equal to 2 volt dents.

For condition monitoring, an evaluation of any indications that satisfy burst margin requirements based on the Westinghouse burst pressure model, but do not satisfy burst margin requirements based on the combined ANL ligament tearing and through-wall burst pressure model.

This item is not applicable. All indications satisfied CM burst margin requirements based on the combined ANL ligament tearing and EPRI through-wall (ANL/TW) burst pressure model, as well as the Westinghouse (WEC) burst pressure model. The CM Westinghouse model burst pressures are shown in Table 5 for both free span and total length. The ANL/TW model CM burst pressures for total length are shown in Table 6.

The total length CM burst requirement was 3367 psi at 1.4 (differential pressure steam line break (dPSLB), based on dPSLB of 2405 psi (PORV setpoint plus uncertainty).

The free span length CM burst requirement was 4419 psi, based on 3APNO.

Performance evaluation of the operational assessment methodology for prediction of flaw distributions as a function of flaw size.

PG&E evaluated the performance of the PWSCC ARC OA methodology for prediction of flaw distributions as a function of flaw size. WCAP-1 5573, Revision 1, provides guidance for determining when corrective actions are needed when a single indication OA prediction significantly underestimates the burst pressure or leak rate when compared to the CM results. When comparing single indication projected leak and burst data with that obtained for the same indication from the inspection results, additional evaluations are to be performed and included in the 120-day report if: (1) the CM single indication burst pressure is less than 5600 psi and more than 500 psi less than the projection obtained using the same burst model; or (2) the CM single indication leak rate is more than 0.2 gpm larger than the projected SLB leak rate.

Performance Evaluation of Single Indication SLB Leak Rates From the prior cycle OA, no single indication leakage was projected at EOC-14 in any SG, either from total length or free span. In 1 R14, no CM single indication leakage was calculated in any SG, either from total length or free span. Therefore, the single indication leak rate methodology using the ANL ligament tearing model is determined to 2-9 PG&E Letter DCL-07-085 be adequately conservative, and no corrective actions are required.

Performance Evaluation of Single Indication Burst Pressures The free span burst pressure for all indications exceeded the default value of 6100 psi for both the prior cycle OA and the CM assessment, using both burst models.

Therefore, the single indication free span burst pressure methodology is determined to be adequately conservative, and no corrective actions are required.

A detailed total length burst pressure benchmarking analysis (CM versus prior cycle OA projections) was performed for the repeat indications that had been left in service in Cycle 14 under PWSCC ARC. As required by the PWSCC ARC, the OA burst pressures are 95/95 values, and the CM burst pressures are 95/50 values. Table 6 provides the results of the benchmarking. For both the Westinghouse model and the ANL/TW model, the total length burst pressures listed in the "prior cycle OA projection" columns were compared against the same model burst pressures in the "CM" columns, and the differences in CM versus OA burst pressures are listed. Three differences are listed: difference between CMOA from the Westinghouse model, difference between CMOA from the ANL/TW model, and difference between CM from the Westinghouse model and OA from the ANL/TW model (since the CM of record uses the Westinghouse model and the OA of record uses the ANL/TW model). Negative differences are underpredictions, while positive differences are overpredictions. Three underpredictions were identified, as discussed below.

SG 1-2 R16C59 crack 1 had underpredictions of 346 psi and 173 psi using the ANL/TW model and Westinghouse model, respectively. It is noted that the indication's length growth rate is in the upper tail of the growth curve. Since the CM burst pressures were less than 5600 psi, these underpredictions do not require evaluation.

SG 1-2 R27C69 crack 1 had underpredictions of 349 psi and 329 psi using the ANL/TW model and Westinghouse model, respectively. The underprediction is only 118 psi when using the models of record. Since these underpredictions are less than the 500 psi threshold value, the single indication total length burst pressure methodology is determined to be adequately conservative, and no corrective actions are required. This tube was plugged as a conservative preventive measure due to a predicted low OA burst pressure.

SG 1-2 R32C30 crack I had underpredictions of 241 psi and 288 psi using the ANL/TW model and Westinghouse model, respectively. The underprediction is only 110 psi when using the models of record. Since these underpredictions are less than the 500 psi threshold value, the single indication total length burst pressure methodology is determined to be adequately conservative, and no corrective actions are required.

Burst pressure benchmarking of the SG 1-2 R8C61 crack 1 merged indication was not conducted due to lack of valid comparison between 1R13 and 1R14. As discussed 2-10 PG&E Letter DCL-07-085 earlier, the merged indications did not undergo significant growth in length and depth over Cycle 14. Table 5 shows a Westinghouse model burst pressure of 6100 psi for the merged indication.

Performance Evaluation of Total SG Monte Carlo SLB Leakage Table 8 provides a summary of SLB leak rates for EOC-14 and EOC-15 for single indication Monte Carlo analyses and total SG Monte Carlo analyses.

Page 7-12 of WCAP-1 5573, Revision 1, requires the following: "If the results of the single indication analyses show leakage for condition monitoring or operational assessment for either free span or total length, then a total SG leak rate Monte Carlo operational assessment is required for each SG that shows leakage. A conservative probability of detection (POD) of 0.6 is used in the SG analysis."

The results of the 1 R14 single indication analysis did not show CM OA leakage for free span and total length analyses, with the exception of two indications that each had 0.001 gpm OA leakage (SG 1-2 R27C69 crack 1 and SG 1-2 R34C53 crack 1). These indications were subsequently removed form service by tube plugging in 1 R14.

Because of this predicted single indication leakage, a total SG leak rate Monte Carlo OA (using a POD of 0.6) was required for SG 1-2 per the WCAP methodology. In addition, total SG leak rate analyses were performed for CM (using a POD of 1.0) and OA (using a POD of 0.6) for all SGs with indications, regardless of the results of single indication leakage analyses, as committed by PG&E in letter DCL-06-29 dated February 24, 2006. The results of the total SG leak rate analyses show that no SG had any CM OA leakage, with the exception of SG 1-2 GA for which the 95/95 leak rate was 2.14 gpm. This 2.14 gpm leak rate value is greater than the 0 gpm leak rate predicted from the single indication Monte Carlo analyses (after 1R14 tube plugging of the two indications that had small 0.001 gpm OA leakage predicted), and is therefore considered to be the licensing basis OA leak rate for PWSCC ARC projections for SG 1-2 at EOC-15.

As discussed in PG&E Letter DCL-06-029, the SG 1-2 leak rate predicted by the prior cycle OA (total SG Monte Carlo) was 1.35 gpm, and no OA leakage was predicted in SG 1-1 and SG 1-4. Because condition monitoring at 1R14 did not calculate any leakage in any SG for both the single indication Monte Carlo analyses and the total SG Monte Carlo analyses, the leak rate OA methodology is determined to be adequately conservative.

2-11 PG&E Letter DCL-07-085 Evaluation results of number and size of previously reported versus new PWSCC indications found in the inspection, and the potential need to account for new indications in the operational assessment burst evaluation.

As discussed above, there were 235 axial PWSCC indications detected in 1R14: 17 new indications and 218 repeat indications. The number of new indications continues to be a small fraction of the total number of indications.

Of the 17 new indications: 3 had no prior Plus Point inspections; 10 had a Plus Point inspection in 1R13, of which 7 were detectable in 1R13 based on a lookup review; 4 had prior Plus Point inspections in outages prior to 1 R1 3, of which 3 were detectable based on a lookup. Only growth rates from 1R13 to 1R14 inspections were included in the growth distribution. In summary, 10 of the 14 new indications with prior inspections could be traced to the prior inspection data, indicating that the indications have a small growth rate progression.

All of the new indications had CM burst pressures in excess of 6100 psi using both the Westinghouse model and the ANL/TW model. The average depths of the new indications were bounded by about 35 percent throughwall. Table 9 shows the frequency, as a function of average depth, of the new indications and repeat indications. As shown in Table 9, the frequency percentage of the new versus repeat trends down with increasing depths, illustrating that depths of new indications do not substantially contribute to the OA burst evaluation.

In conclusion, because of the low frequency and small average depths of new indications relative to repeat indications, slow growth rates of new indications, and CM burst pressures of new indications well in excess of burst margin requirements, there is no need to account for new indications in the OA burst evaluation.

Identification of mixed mode (axial PWSCC and circumferential) indications found in the inspection and an evaluation of the mixed mode indications for potential impact on the axial indication burst pressures or leakage. In addition, performance of a trending analysis to assess the potential for increasing mixed mode affects (e.g.. circumferential crack depths, burst pressure reductions, increased leakage rates) over time.

For PWSCC ARC, a mixed mode indication is defined as an axial PWSCC indication and a circumferential indication (either PWSCC or ODSCC) occurring at the same dented TSP intersection. The indications are termed PWSCC mixed mode. No PWSCC mixed mode indications were detected in 1R14.

There are several conditions that require evaluation to determine the need for corrective actions. These are discussed below:

If an interacting PWSCC mixed-mode indication is found to have led to a reduction in the axial indication burst pressure by more than 10 percent and to less than 2-12 PG&E Letter DCL-07-085 4000 psi, or to have caused an indication to not satisfy burst margin requirements, the burst margin requirements for implementation in the OA at the next and subsequent outages must be increased by the percentage reduction in the burst pressure found for the mixed mode indication. As discussed above, because no mixed-mode indications were detected in 1 R14, this condition did not occur and there are no corrective actions needed to adjust burst margin requirements for future operational assessments.

If an interacting PWSCC mixed-mode indication is found, and the axial indication condition monitoring predicts SLB leakage at 95/50, and the circumferential indication has greater than 50 percent average depth including NDE uncertainty, then the CM leak rate for the axial indication must be increased by a leakage factor.

In addition, the OA SLB leak rate for each SG must be increased by a leakage factor. As discussed above, because no mixed-mode indications were detected in I R14, this condition did not occur and there are no corrective actions needed to adjust SLB leak rates for CM or OA.

" If a previously Plus Point-inspected TSP intersection is found to have a circumferential indication with average depth greather than 80 percent after accounting for NDE uncertainty, then the OA SLB leak rate for each SG must be increased by a leakage factor. There were 14 TSP circumferential indications detected in 1R14 (1 PWSCC and 13 ODSCC). All of the TSPs with circumferential indications detected in 1R14 were previously Plus Point inspected in 1R13. The deepest 1R14 circumferential indication was 69.8 percent average depth, including 95 percent NDE uncertainty, less than the 80 percent average depth threshold. The maximum Plus Point amplitude for this flaw was only 0.17 volt, and it is expected that the flaw is very conservatively sized. Therefore, no corrective actions are needed to adjust the OA SLB leak rates.

In response to NRC request for additional information, PG&E Letter DCL-02-045, committed to performing a trending analysis in the 120-day report to assess the potential for increasing mixed mode affects (e.g., circumferential crack depths, burst pressure reductions, increased leakage rates) over time. Since no burst pressure reductions or leakage rate multipliers have been required, there is no data to trend for these parameters. Trending of circumferential depths, maximum voltages, and number of circumferential indications is provided in Figures 1, 2, 3, and 4.

Figure 1 provides all DCPP Unit 1 TSP PWSCC and ODSCC circumferential indication measured adjusted average depths versus year detected. The adjustments do not include NDE uncertainty. The mean trend line (excluding 1995 data since Plus Point inspections were conducted for the first time in that year) shows a slight increase in average depths over time. The frequency of larger depths tends to show an oscillating up and down pattern between outages, which is a result of conservative sizing of low amplitude flaws (less than 1 volt). Because of the large frequency of low amplitude flaws, a more realistic trend of depths over time is shown in Figure 2, which plots the same data in terms of maximum voltage. The mean trend line shows a slight decrease in maximum voltage over time, even when excluding the 1995 data. Thus, there are no 2-13 PG&E Letter DCL-07-085 increasing depths over time associated with TSP circumferential indications.

Figure 3 data is a subset of Figures 1 and 2, showing only the PWSCC mixed mode circumferential indication average depths and maximum voltages versus year detected.

A total of three PWSCC mixed mode indications have been detected in DCPP Unit 1.

No PWSCC mixed mode indications were detected in 1R13 and 1R14. The maximum voltages show a decreasing trend, although there are only three data points being trended.

Figure 4 provides the number of DCPP Unit 1 TSP PWSCC and ODSCC circumferential indications detected over time, which shows an increasing trend. The increase is attributed to an increasing number of circumferential ODSCC indications, whereas the number of circumferential PWSCC indications has trended down. The most likely reason for increased numbers of ODSCC indications is due to increased operation time at a higher stress state associated with dented TSPs. Chemical cleaning in the Unit 1 twelfth refueling outage (1 RI 2) did not clean the TSP crevices, and has no affect on detection capability of ODSCC.

Even though there is an increasing trend in the number of circumferential indications, the indications are being detected at an early stage as reflected in the trend of decreasing maximum voltages. In addition, there were no PWSCC mixed mode indications detected in 1R13 and 1R14. Therefore, there is not a significant potential for increasing mixed mode affects over time.

Any corrective actions found necessary in the event that condition monitoring requirements are not met.

This item is not applicable, because all indications satisfied CM burst margin requirements and leakage margin requirements.

All CM burst pressures, evaluated at 95 percent probability and 50 percent confidence (95/50), exceeded the 3367 psi total length SLB burst margin requirement and the 4419 psi free span burst margin requirement, using both the Westinghouse model and the ANL/TW model.

CM single indication SLB leak rates were evaluated at 95 percent probability and 50 percent confidence (95/50), using the ANL ligament tearing model. No free span leakage was calculated, and no total length leakage was calculated. In addition, total SG leak rate Monte Carlo CM analyses were performed for each SG with indications, and no free span or total length leakage was calculated at 95/50 confidence levels using a POD of 1.0. Table 8 summarizes these leak rate calculations.

2-14 PG&E Letter DCL-07-085 1R14 Minimum Scope Table 1 for Plus Point Inspection of Dented TSP (Based on 1R13 Dent Population)

Intersections 2-5 Volt Dents TSP SG 1-1 SG 1-2 SG 1-3 SG 1-4 TOTAL 1H 14 149 50 326 539 2H 49 132 130 311 3H 16 93 193 302 4H 5

96 112 213 5H 6

58 75 139 6H 18 194 212 7H 99 50 149 7C 26 26 6C 1

1 TOTAL 90 672 50 1080 1892

> 5 Volt Dents TSP SG 1-1 SG 1-2 SG 1-3 SG 1-4 TOTAL 1 H 1

67 15 333 416 2H 17 59 4

50 130 3H 5

54 10 59 128 4H 2

67 6

81 156 5H 4

16 38 35 93 6H 1

1 16 231 249 7H 50 27 50 68 195 7C 5

5 6C 0

5C 0

4C 0

3C 0

2C 0

1 C 0

TOTAL 80 296 139 857 1372

<_ 2 Volt Dents TSP

]

SG 1-1 J

SG 1-2 SG 1-3 I

SG 1-4 TOTAL 1H 199 199 2H 50 50 TOTAL 249 249 1 R14 Plus Point dent inspection criteria:

SG 1-1: 100% of <2 volt dents at 1H, 20% at2H 100% of >2 and <5 volt dents from 1 H to 4H, 20% at 5H 100% of >5 volt dents from 1 H to 4H, 20% from 5H to 7H SG 1-2: 100% of >2 and <5 volt dents from 1 H to 7C, 20% at 6C 100% of >5 volt dents from 1 H to 7C, 20% at 6C (Note: There are no >5 volt dents at 1 C-6C)

SG 1-3: 20% of >2 and <5 volt dents at 1H 20% of ->5 volt dents from 1 H to 7H SG 1-4: 100% of >2 and <5 volt dents from 1 H to 6H, 20% at 7H 100% of -Ž5 volt dents from 1 H to 6H, 20% at 7H All 20% samples shall contain a minimum of 50 dents. If the population of dents at the TSP elevation is less than 50, then inspect 100% of the dents at the TSP.

2-15 PG&E Letter DCL-07-085 Table 2 Axial PWSCC~ C.,mulative Prnbihilitv Distrihbution ICPflI (rowth Ralt* npr I=FPY at f04F Cycle 12 Cycle 13 Cycle 15 Prelim OA Cycle 14 Cycle 15 Final OA Length Bin Lower Bound CPD Frequency CPD Same as prelim OA (inch)

Frequency CPD Frequency CPD from Cycle 12-13 0

78 0.363 58 0.257 0.257 119 0.531 0.01 24 0.474 27 0.376 0.376 29 0.661 0.02 45 0.684 24 0.482 0.482 21 0.754 0.03 17 0.763 34 0.633 0.633 25 0.866 0.04 19 0.851 19 0.717 0.717 7

0.897 0.05 14 0.916 14 0.779 0.779 6

0.924 0.06 7

0.949 21 0.872 0.872 10 0.969 0.07 5

0.972 7

0.903 0.903 3

0.982 0.08 1

0.977 3

0.916 0.916 3

0.996 0.09 4

0.995 4

0.934 0.934 0

0.996 0.1 1

1.000 4

0.951 0.951 0

0.996 0.11 0

1.000 1

0.956 0.956 1

1.000 0.12 0

1.000 2

0.965 0.965 0

1,000 0.13 0

1.000 1

0.969 0.969 0

1.000 0.14 0

1.000 0

0.969 0.969 0

1.000 0.15 0

1.000 6

0.996 0.996 0

1.000 0.16 0

1.000 0

0.996 0.996 0

1.000 0.17 0

1.000 0

0.996 0.996 0

1.000 0.18 0

1.000 1

1.000 1.000 0

1.000 Cycle 12 Cycle 13 Cycle 15 Prelim OA Cycle 14 Cycle 15 Final OA MD Bin (%TW Lower Bound CPD fraction)

Frequency CPD Frequency CPD from cle Frequency CPD Same as prelim OA fracion)from Cycle 12-13 0

63 0.293 141 0.624 0.293 84 0.375 0.01 8

0.330 14 0.686 0.330 11 0.424 0.02 20 0.423 9

0.726 0.423 15 0.491 0.03 16 0.498 17 0.801 0.498 32 0.634 0.04 19 0.586 5

0.823 0.586 9

0.674 0.05 28 0.716 13 0.881 0.716 21 0.768 0.06 7

0.749 7

0.912 0.749 14 0.830 0.07 11 0.800 4

0.929 0.800 8

0.866 0.08 7

0.833 1

0.934 0.833 10 0.911 0.09 9

0.874 5

0.956 0.874 3

0.924 0.1 10 0.921 3

0.969 0.921 1

0.929 0.11 2

0.930 0

0.969 0.930 8

0.964 0.12 7

0.963 2

0.978 0.963

'3 0.978 0.13 1

0.967 0

0.978 0.967 2

0.987 0.14 1

0.972 1

0.982 0.972 0

0.987 0.15 2

0.981 1

0.987 0,981 0

0.987 0.16 2

0,991 0

0.987 0,987 1

0.991 0.17 0

0,991 0

0.987 0.987 1

0.996 0.18 0

0.991 1

0.991 0.991 0

0.996 "0.19 0

0.991 0

0.991 0,991 1

1.000 0.2 2

1.000 0

0.991 0.991 0

1.000 0.21 0

1.000 1

0.996 0,996 0

1.000 0.22 0

1.000 0

0.996 0.996 0

1.000 0.23 0

1.000 1

1.000 1.000 0

1.000 2-16 PG&E Letter DCL-07-085 Table 2 Axial PWSCC Cumulative Probability Distribution (CPD) Growth Rates per EFPY at 604F Cycle 12 Cycle 13 Cycle 15 Prelim OA Cycle 14 Cycle 15 Final OA AD Bin (%TW Lower Bound CPD Same as prelim OA fraction)

Frequency CPD Frequency CPD from Cycle 12-13 Frequency CPD except for 0.00% and 0.08% bins 0

53 0.247 112 0.496 0.247 53 0.237 0.237 0.01 25 0.363 33 0.642 0.363 30 0.371 0.363 0.02 24 0.474 19 0.726 0.474 32 0.513 0.474 0.03 17 0.553 23 0.827 0.553 18 0.594 0.553 0.04 23 0.660 12 0.881 0.660 21 0.688 0.660 0.05 23 0.767 10 0.925 0.767 26 0.804 0.767 0.06 18 0.851 7

0.956 0.851 11 0.853 0.851 0.07 12 0.907 3

0.969 0.907 14 0.915 0.907 0.08 6

0.935 2

0.978 0.935 4

0.933 0.933 0.09 2

0.944 0

0.978 0.944 8

0.969 0.944 0.1 4

0.963 1

0.982 0.963 3

0.982 0.963 0.11 1

0.967 1

0.987 0.967 1

0.987 0.967 0.12 2

0.977 1

0.991 0.977 2

0.996 0.977 0.13 2

0.986 0

0.991 0.986 1

1.000 0.986 0.14 3

1.000 2

1.000 1.000 0

1.000 1.000 0.15 0

1.000 0

1.000 1.000 0

1.000 1.000 0.16 0

1.000 0

1.000 1.000 0

1.000 1.000 0.17 0

1.000 0

1.000 1.000 0

1.000 1.000 0.18 0

1.000 0

1.000 1.000 0

1.000 1.000 0.19 0

1.000 0

1.000 1.000 0

1.000 1.000 0.2 0

1.000 0

1.000 1.000 0

1.000 1.000 Total 215 226 224 2-17 PG&E Letter DCL-07-085 Table 3 Unit 1 Growth Rates per EFPY at 604F 90 Percentile Growth per EFPY 95 Percentile Growth per EFPY Data Length Max Average Length Max Average Cycle Points inch Depth %

Depth %

inch Depth %

Depth %

11 119 0.035 6.67 6.14 0.050 8.58 8.03

12.

215 0.050 9.69 6.88 0.060 11.37 9.14 13 226 0.067 5.78 4.40 0.097 8.77 5.62 14 224 0.041 7.91 6.83 0.050 10.79 8.61 Table 4 1R14 DIS Confirmation Rates SG 1-1 SG 1-2 SG 1-3 SG 1-4 Total Number of bobbin DIS in less than or equal to 2 volt dented TSP intersections (excludes 32 66 18 16 132 repeat PWSCC indications)

Number of new PWSCC indications 2

6 0

0 8

confirmed by Plus Point Plus Point confirmation rate 6%

9%

0%

0%

6%

Bobbin DIS overcall rate 94%

91%

100%

100%

94%

2-18 PG&E Letter DCL-07-085 Table 5 - 1 R14 PWSCC ARC Summary of Analysis Results Condition Monitoring Operational Assessment Adjusted NDE (WEC Model)

(ANLITW Model)

Total Total Total Total Max.

Avg.

Max.

FS Burst FS Length FSBurst FS Leng SG R C TSP Crack Cal Plug reason Ind cat (in.) Depth Depth From To Pressure Leakage Burst Length Pressure Leakage Burst Lenge No.(%)

(%.) Volts psi gpm Press.

psi gpm Press. Leakage psi gpm psi gpm 1 3 28 02H 1

16 Repeat 0.16 45.0 31.1 0.92 -0.22 -0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 4 41 01H 1

16 Repeat 0.15 26.0 20.2 0.64 -0.05 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 14 28 02H 1

16 Repeat 0.14 34.0 22.6 0.59 0.19 0.33 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 15 16 02H 1

16 Repeat 0.08 20.0 10.9 0.44 -0.08 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 15 76 02H 1

16 Repeat 0.12 34.0 24.3 0.68 -0.16 -0.04 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 17 16 02H 1

16 Repeat 0.19 37.0 28.3 1.11 -0.21 -0.02 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 19 15 03H 1

16 Repeat 0.36 51.0 37.6 1.54 -0.21 0.15 6100 0.000 6100 0.000 6100 0.000 5527 0.000 1 19 15 7C 1

56 New 0.28 48.0 34.8 1.03 -0.21 0.07 6100 0.000 6100 0.000 6100 0.000 5945 0.000 1 20 28 02H 1

16 Repeat 0.14 34.0 25.3 1.26 -0.22 -0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 20 29 02H 1

16 Repeat 0.33 37.0 26.0 1.00 -0.04 0.29 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 20 33 01H 1

16 Repeat 0.08 20.0 14.2 0.34 -0.14 -0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 21 13 03H 1

16 Repeat 0.20 37.0 27.8 1.35 -0.14 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 21 51 02H 1

16 Repeat 0.08 20.0 13.3 0.54 -0.14 -0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 21 54 01H 1

16 Repeat 0.17 60.0 38.0 1.09 -0.16 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 23 14 03H 1

16 Repeat 0.12 39.0 27.9 0.93 -0.13 -0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 24 67 02H 1

16 Repeat 0.26 54.0 39.8 1.38 -0.18 0.08 6100 0.000 6100 0.000 6100 0.000 5749 0.000 1 25 57 03H 1

16 Repeat 0.33 42.0 35.7 1.04 -0.13 0.20 6100 0.000 6100 0.000 6100 0.000 5756 0.000 1 27 75 02H 1

16 Repeat 0.14 31.0 21.3 0.92 -0.08 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 28 23 03H 1

66 New 0.22 42.0 27.7 0.85 -0.16 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 29 37 02H 1

16 Repeat 0.28 37.0 30.0 1.00 -0.08 0.20 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 30 21 02H 1

16 Repeat 0.12 34.0 22.7 0.69 -0.11 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 30 59 02H 1

16 Repeat 0.22 31.0 24.8 0.86 -0.19 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 30 67 02H 1

16 Repeat 0.32 39.0 29.8 1.31 -0.18 0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 34 24 03H 1

16 Repeat 0.16 42.0 29.0 0.74 -0.08 0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 34 24 03H 2

16 Repeat 0.14 37.0 26.2 0.57 0.08 0.22 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 35 59 03H 1

16 Repeat 0.33 51.0 38.2 1.85 -0.21 0.12 6100 0.000 6100 0.000 6100 0.000 5601 0.000 1 38 41 04H 1

16 Repeat 0.26 45.0 32.9 1.45 -0.35 -0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 1 39 57 02H 1

16 Repeat 0.17 26.0 14.6 0.84 -0.24 -0.07 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 2 10 03H 1

17 Repeat 0.39 48.0 36.9 1.59 -0.09 0.30 6100 0.000 6100 0.000 6100 0.000 5489 0.000 2

2 28 03H 1

17 Repeat 0.24 45.0 29.4 0.98 -0.22 0.02 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 2 67 02H 1

59 New 0.16 31.0 20.8 0.82 -0.10 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 2 76 02H 1

15 Repeat 0.19 20.0 12.0 0.57 -0.22 -0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-19 PG&E Letter DCL-07-085 Table 5 - 1 R1 4 PWSCC ARC Summary of Analysis Results Condition Monitoring Operational Assessment (WEC Model)

(ANL/TW Model)

Total Total Total Length Max Avg.

FS Burst FS Length Tota FS Burst FS Length L Cralk Legt Erom Togt PrssreLakgeBus SG R C TSP Crackal Plug reason Ind cat (in.)

Depth Depth Max. From To Pressure Leakage Burst Leakage Pressure Leakage Burst Leakage No.

(%)

(%) Volts psi gpm Press.

ge psi gpm Press.

ge psi gpm ps gpm 2

2 78 01H 1

15 Repeat 0.09 20.0 12.6 0.55 0.10 0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 79 03H 1

15 Repeat 0.50 35.0 25.4 1.02 -0.18 0.32 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 90 03H 1

15 Repeat 0.22 21.5 9.5 0.56 -0.13 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 90 04H 1

15 Repeat 0.14 37.0 25.8 1.15 -0.41 -0.27 6100 0.000 6100 0.000 6100 0.000 6100 0.000 22 9004H 2

15 Repeat 0.28 45.0 32.2 1.76 -0.16 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 92 05H 1

15 Repeat 0.09 20.0 10.5 0.43 -0.49 -0.40 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 92 05H 2

15 Repeat 0.10 20.0 11.0 0.72 -0.07 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 92 05H 3

15 Repeat 0.23 21.5 14.1 0.75 0.03 0.26 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

2 93 04H 1

15 Repeat 0.12 36.5 25.5 0.63 0.14 0.26 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

3 46 7C 1

47 Repeat 0.28 38.0 29.2 0.67 -0.16 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

4 54 02H 1

16 Repeat 0.26 42.0 28.4 1.11 -0.10 0.16 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

4 57 01H 1

16 Repeat 0.11 20.0 11.9 0.58 0.01 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

4 84 01H 1

15 Repeat 0.17 26.0 17.3 0.65 0.02 0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

5 66 02H 1

15 Repeat 0.16 31.0 21.0 0.81 -0.15 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

5 72 02H 1

59 IDOD New 0.17 20.0 10.0 0.42 -0.29 -0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

5 77 05H 1

15 Repeat 0.23 42.0 34.4 1.22 -0.31 -0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

5 78 01H 1

15 Repeat 0.42 51.0 33.2 1.29 -0.01 0.41 6100 0.000 6100 0.000 6100 0.000 5642 0.000 2

5 93 01H 1

15 Repeat 0.41 42.0 29.6 1.74 -0.27 0.14 6100 0.000 6100 0.000 6100 0.000 5892 0.000 2 6557C 1

47 Repeat 0.24 34.0 25.1 0.77 -0.20 0.04 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

6 74 03H 1

15 Repeat 0.07 20.0 12.9 0.53 -0.50 -0.43 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

6 74 03H 2

15 Repeat 0.24 31.0 19.2 1.03 -0.19 0.05 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 7 17 04H 1

17 Repeat 0.18 48.0 30.0 0.78 -0.06 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

7 23 02H 1

24 New 0.54 23.0 15.3 0.80 -0.29 0.25 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

7 31 01H 1

17 IDOD Repeat 0.33 48.0 35.5 1.15 -0.01 0.32 6100 0.000 6100 0.000 6100 0.000 5752 0.000 2

7 31 7C 1

47 IDOD at 1H Repeat 0.61 60.0 46.8 1.99 -0.34 0.27 6100 0.000 5217 0.000 6100 0.000 4146 0.000 2 75303H 1

16 Repeat 0.23 37.0 25.0 0.78 -0.05 0.18 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

7 68 03H 1

15 Repeat 0.14 37.0 22.8 0.97 0.14 0.28 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

7 86 02H 1

45 New 0.10 20.5 14.0 0.55 -0.04 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2

8 4 05H 1

16 Repeat 0.34 48.0 40.3 1.52 -0.31 0.03 6100 0.000 6100 0.000 6100 0.000 5428 0.000 2

8 15 02H 1

17 Repeat 0.27 54.0 39.3 1.54 -0.13 0.14 6100 0.000 6100 0.000 6100 0.000 5755 0.000 2

8 48 01H 1

13 Repeat 0.19 23.0 16.0 0.66 -0.22 -0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 8 55 01H 1

16 Repeat 0.27 57.0 41.3 1.86 -0.18 0.09 6100 0.000 6100 0.000 6100 0.000 5557 0.000 2-20 PG&E Letter DCL-07-085 Table 5 - 1 R1 4 PWSCC ARC Summary of Analysis Results AdutdNECondition Monitoring Operational Assessment Adjusted NDE(WEC Model)

____(ANL/TW Model)

TtlTotal Total Total Crack LeghMx

v.

M ax FS Burst ES Length Tontal ES Burst ES Length Length SG R C TSP No.

Cal Plug reason Ind cat Length Depth Avg.h Max.s From To Pressure Leakage Burst Lenkgth Pressure Leakage BurstLekg (i.

Det Volsi gpm Press. Leaag g M Press.Lekg pi gpm pi gpm 2 8 57 01H 1

16 Repeat 0.46 60.0 44.8 2.71 -0.29 0.17 6100 0.000 5729 0.000 6100 0.000 4713 0.000 2 8 61 02H 1

15 Merged 0.59 48.0 38.9 1.81 -0.33 0.26 6100 0.000 6100 0.000 6100 0.000 4830 0.000 2 8 61 02H 2

15 New 0.09 20.0 11.6 0.3610.08 0.17 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 8 66 02H 1

15 Repeat 0.14 34.0 25.3 0.85 -0.33 -0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 8 82 04H 1

15 Repeat 0.33 28.0 18.9 0.49 -0.13 0.20 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 8 93 01H 1

15 Repeat 0.25 50.5 30.3 1.42 -0.26 -0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 27 03H 1

17 Repeat 0.08 20.0 13.0 0.35 -0.13 -0.05 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 30 01H 1

17 Repeat 0.49 60.0 49.8 2.67 -0.26 0.23 6100 0.000 5340 0.000 6100 0.000 4301 0.000 2 9 38 02H 1

17 Repeat 0.44 54.0 45.1 3.01 -0.30 0.14 6100 0.000 5727 0.000 6100 0.000 4738 0.000 2 9 45 01H 1

17 Repeat 0.20 48.0 28.2 1.33 0.02 0.22 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 53 01H 1

16 Repeat 0.35 45.0 34.3 1.41 -0.14 0.21 6100 0.000 6100 0.000 6100 0.000 5805_

0.000 2 9 56 01H 1

16 Repeat 0.22 51.0 39.1 1.60 -0.36 -0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 75 02H 1 48 New 0.10 20.0 8.2 0.34 -0.34 -0.24 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 82 03H 1

15 Repeat 0.25 42.0 30.5 1.58 0.09 0.34 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 9 83 04H 1 59 New 0.25 42.0 28.9 1.38 -0.19 0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 49 03H 1

16 Repeat 0.37 23.0 12.4 0.68 -0.12 0.25 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 62 O1H 1 15 Repeat 0.32 51.0 37.2 1.34 -0.11 0.21 6100 0.000 6100 0.000 6100 0.000 5663 0.000 2 10 62 01H 2

15 New 0.11 20.0 11.3 0.33 -0.14 -0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 67 01H 1

15 SCI OD 2H Repeat 0.27 20.0 13.5 1.00 -0.26 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 68 01H 1

15 Repeat 0.23 42.0 32.7 1.75 -0.24 -0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 69 02H 1

15 Repeat 0.12 28.5 18.9 0.62 -0.27 -0.15 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 10 85 04H 1

15 Repeat 0.12 34.0 21.4 0.69 0.18 0.30 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 20 02H 1

17 Repeat 0.27 54.0 42.9 1.84 -0.06 0.21 6100 0.000 6100 0.000 6100 0.000 5503 0.000 2 11 45 01H 1

17 Repeat 0.47 37.0 21.0 1.23 -0.13 0.34 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 66 03H 1

15 Repeat 0.23 38.0 30.1 1.04 -0.20 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 71 01H 1

15 Repeat 0.30 48.0 35.2 1.42 -0.33 -0.03 6100 0.000 6100 0.000 6100 0.000 5904 0.000 2 11 71 01H 2

15 Repeat 0.06 20.0 11.3 0.54 0.04 0.10 6100 0.000 610 0 0.000 6100 0.000 6100 0.000 2 11 71 01H 3

15 Repeat 0.19 45.0 31.1 1.33 -0.18 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 71 01H 4

15 Repeat 0.39 26.0 19.5 0.58 -0.17 0.22 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 84 02H 1

15 Repeat 0.47 42.0 20.6 1.20 -0.26 0.21 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 11 87 01H 1

15 Repeat 0.40 73.0 48.1 2.55 -0.22 0.18 6100 0.000 5565 0.000 6100 0.000 4626 0.000 2 13120 03H 1 60 New 0.24 51.0 35.1 1.06 -0.15 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-21 PG&E Letter DCL-07-085 Table 5 - 1R14 PWSCC ARC Summary of Analysis Results Adjusted NDE Condition Monitoring Operational Assessment (WEC Model)

(ANL/TW Model)

Total Total Total Crack Length Max.

Avg.

Ma FS Burst FS Length Length FS Burst FS Length Length SG R C TSP Cal Plug reason Ind cat Depth Depth

x. From To Pressure Leakage Burst Lengt Pressure Leakage Burst No.

(in.)

t Volts Press.

eLakg

(%)

(%)

psi gpm PressL.

psi gpm Press.

psi gpm psi gpm 2 13 34 01H 1

17 Repeat 0.18 51.0 37.6 1.31 0.04 0.22 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 13 44 01H 1

17 Repeat 0.25 60.0 48.6 2.27 -0.13 0.12 6100 0.000 6100 0.000 6100 0.000 5218 0.000 2 13 60 02H 1

16 Repeat 0.26 54.0 35.6 1.47 -0.15 0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 16 04H 1

17 Repeat 0.25 48.0 36.3 1.12 -0.13 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 45 01H 1

17 Repeat 0.09 20.0 12.6 0.55 -0.02 0.07 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 58 04H 1

16 Repeat 0.09 28.0 19.0 0.55 0.14 0.23 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 68 O1H 1

15 Repeat 0.43 20.0 13.2 0.88 -0.22 0.21 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 70 01H 1

15 Repeat 0.09 22.0 11.6 0.34 -0.09 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 14 74 01H 1

15 Repeat 0.26 32.5 20.8 1.15 -0.26 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 12 05H 1

17 Repeat 0.07 31.0 18.5 0.61 -0.05 0.02 6100 0.000 6100 0.000 6100 0,000 6100 0.000 2 16 59 02H 1

15 Repeat 0.32 57.0 45.9 2.39 -0.09 0.23 6100 0.000 5927 0.000 6100 0.000 5064 0.000 2 16 60 02H 1

15 Repeat 0.09 22.0 14.0 0.48 -0.23 -0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 82 01H 1

15 Repeat 0.23 23.0 12.6 0.74 -0.08 0.15 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 82 04H 1

15 Repeat 0.30 45.0 32.3 1.01 -0.10 0.20 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 85 02H 1

14 Repeat 0.26 37.0 27.2 0.79 -0.25 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 87 02H 1

14 Repeat 0.21 48.0 37.9 1.47 -0.02 0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 88 02H 1

14 Repeat 0.22 48.0 35.3 1.44 -0.14 0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 16 88 02H 2

14 Repeat 0.09 20.0 9.8 0.37 -0.29 -0.20 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 17 9 06H 1

16 Repeat 0.12 28.0 17.4 0.71 -0.13 -0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 17 54 01H 1

15 Repeat 0.37 60.0 51.9 2.27 -0.13 0.24 6100 0.000 5393 0.000 6100 0.000 4533 0.000 2 17 59 01H 1

15 Repeat 0.27 48.0 39.3 1.73 -0.02 0.25 6100 0.000 6100 0.000 6100 0.000 5707 0.000 2 17 66 01H 1

15 Repeat 0.41 45.0 36.6 2.35 -0.26 0.15 6100 0.000 6100 0.000 6100 0.000 5437 0.000 2 17 67 01H 1

15 Repeat 0.24 54.0 25.7 1.09 -0.35 -0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 17 88 01H 1

14 Repeat 0.36 34.0 22.7 0.87 -0.14 0.22 6100 0.000 6100 0.000 6100 0,000 6100 0.000 2 17 88 02H 1

14 Repeat 0.36 20.0 12.1 0.98 -0.07 0.29 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 18 64 03H 1

15 Repeat 0.16 26.0 13.5 0.83 -0.21 -0.05 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 18 67 01H 1

14 Repeat 0.20 45.0 36.4 1.23 -0.27 -0.07 6100 0.000 6100 0.000 6100 0,000 6100 0.000 2 19 34 02H 1

17 Repeat 0.49 48.0 37.9 2.55 -0.20 0.29 6100 0.000 6100 0.000 6100 0.000 5147 0.000 2 19 74 02H 1

14 Repeat 0.15 31.0 17.4 0.67 -0.17 -0.02 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 19 84 03H 1

14 Repeat 0.22 54.0 37.4 1.01 -0.14 0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 20 14 02H 1

27 New 0.07 26.0 15.7 0.45 -0.04 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 20 48 03H 1

13 Repeat 0.30 34.0 21.2 0.72 -0.19 0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-22 PG&E Letter DCL-07-085 Table 5 - 1R14 PWSCC ARC Summary of Analysis Results Condition Monitoring Operational Assessment (WEC Model)

(ANLITW Model)

Total Total Total Total TtlTotal ES Burst ES Length Lenthl Crack Length Max.

Avg.

Max FS Burst FS Length Length FS Burst Lenge SG R C TSP Cal Plug reason Ind cat(in.)

Depth Depth From To Pressure Leakage Burst Leg Pressure Leakage Burst

(%)

(%)

psi gpm Press.

psi gpm Press.

psi gpm psi gpm 2 20 77 01H 1

14 Repeat 0.30 42.0 33.0 1.19 -0.16 0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 21 38 01H 1

17 Repeat 0.29 57.0 46.7 2.49 -0.13 0.16 6100 0.000 6100 0.000 6100 0.000 5183 0.000 2 21 57 01H 1

13 Repeat 0.40 54.0 39.9 1.78 -0.22 0.18 6100 0.000 6100 0.000 6100 0.000 5280 0.000 2 21 60 02H 1

14 Repeat 0.29 28.5 18.8 0.71 -0.26 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 21 65 02H 1

14 Repeat 0.43 54.0 36.5 2.11 -0.15 0.28 6100 0.000 6100 0.000 6100 0.000 5458 0.000 2 21 77 01H 1

59 New 0.19 28.0 19.4 0.93 -0.07 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 22 42 01H 1

17 Repeat 0.31 48.0 34.8 1.74 -0.01 0.30 6100 0.000 6100 0.000 6100 0.000 5882 0.000 2 22 55 03H 1

13 Repeat 0.33 51.0 39.3 1.47 -0.08 0.25 6100 0.000 6100 0.000 6100 0.000 5512 0.000 2 23 25 03H 1

17 Repeat 0.26 37.0 25.0 1.13 -0.34 -0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 23 54 01H 1

13 Repeat 0.18 37.0 23.3 0.61 0.03 0.21 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 23 79 01H 1

14 Repeat 0.07 37.0 25.8 0.46 -0.13 -0.06 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 24 77 01H 1

14 Repeat 0.19 34.0 22.4 0.87 -0.22 -0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 17 02H 1

17 Repeat 0.25 51.0 35.7 1.19 -0.34 -0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 50 02H 1

13 Repeat 0.42 60.0 47.9 2.73 -0.26 0.16 6100 0.000 5551 0.000 6100 0.000 4614 0.000 2 25 55 02H 1

13 Repeat 0.09 26.0 15.1 0.43 0.14 0.23 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 79 02H 1

14 Repeat 0.09 42.0 24.8 1.07 -0.12 -0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 79 02H 2

14 Repeat 0.08 54.0 36.8 1.38 -0.03 0.05 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 85 04H 1

14 Repeat 0.22 32.5 22.8 0.95 -0.17 0.05 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 25 87 04H 1

14 Repeat 0.29 57.0 46.8 1.54 -0.19 0.10 6100 0.000 6100 0.000 6100 0.000 5160 0.000 2 26 22 04H 1

17 Repeat 0.28 51.0 38.1 1.82 -0.07 0.21 6100 0.000 6100 0.000 6100 0.000 5765 0.000 2 26 39 02H 1

17 Repeat 0.11 45.0 32.2 1.02 -0.04 0.07 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 26 48 04H 1

34 DOP>40%

New 0.10 57.0 35.3 1.04 -0.42 -0.32 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 26 73 01H 1

14 Repeat 0.20 48.0 35.7 2.00 -0.10 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 26 79 01H 1

14 Repeat 0.40 60.0 46.2 1.37 -0.20 0.20 6100 0.000 5672 0.000 6100 0.000 4733 0.000 2 27 55 01H 1

13 Repeat 0.07 34.0 20.9 0.64 0.20 0.27 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 56 01H 1

13 Repeat 0.09 20.0 14.8 0.57 -0.21 -0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 63 02H 1

13 Repeat 0.28 60.0 49.2 2.20 -0.33 -0.05 6100 0.000 5817 0.000 6100 0.000 5037 0.000 2 27 63 02H 2

13 Repeat 0.63 48.0 28.2 1.34 -0.34 0.29 6100 0.000 6100 0.000 6100 0.000 5549 0.000 2 27 64 03H 1

14 AONDB 1H >5v DNT Repeat 0.25 23.0 12.4 0.75 -0.13 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 65 02H 1

14 Repeat 0.40 64.0 44.2 1.69 -0.20 0.20 6100 0.000 5810 0.000 6100 0.000 4868 0.000 2 27 67 01H 1

14 Repeat 0.43 60.0 37.7 2.23 -0.34 0.09 6100 0.000 6100 0.000 6100 0.000 5198 0.000 2 27 67 01H 2

14 Repeat 0.14 31.0 22.6 0.85 0.58 0.72 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-23 PG&E Letter DCL-07-085 Table 5 - 1R14 PWSCC ARC Summary of Analysis Results Condition Monitoring Operational Assessment (WEC Model)

(ANLITW Model)

Total Total Total Total Crack Length Max.

Avg.

Max.

FS Burst FS Length Toth FS Burst FS Length Length SNo R C TSP N.

Cal Plug reason Ind cat (in.)

Depth Depth V From To Pressure Leakage Burst Leakag Pressure Leakage Burst

(%)

(%)

psi gpm Press.

psi gpm Press.

psi gpm psi 9pm 2 27 67 04H 1

14 Repeat 0.35 39.0 26.1 1.02 -0.25 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 69 01H 1

14 Preventive low OA burst C1 Repeat 0.43 80.0 58.7 2.81 -0.30 0.13 6100 0.000 4682 0.000 6100 0.000 3808 0.001 2 27 69 01H 2

14 Preventive low OA burst C1 Repeat 0.22 31.0 20.5 0.95 -0.03 0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 72 02H 1

14 Repeat 0.14 28.0 22.7 0.73 -0.30 -0.16 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 72 02H 2

14 Repeat 0.16 20.0 9.5 0.47 0.11 0.27 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 27 73 04H 1

59 New 0.30 28.0 20.2 0.77 -0.20 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 28 25 02H 1

30 New 0.14 26.0 16.0 0.50 -0.25 -0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 28 25 02H 2

30 New 0.09 20.0 11.9 0.58 -0.01 0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 28 47 03H 1

13 Repeat 0.23 31.0 23.9 1.00 0.04 0.27 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 28166 02H 1

14 Repeat 0.09 31.0 21.3 0.60 -0.02 0.07 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 29 51 02H 1

13 Repeat 0.16 31.0 20.1 0.81 -0.08 0.08 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 29 66 01H 1

14 Repeat 0.15 54.0 39.7 1.79 -0.06 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 30 56 01H 1

13 Repeat 0.50 67.0 50.7 2.99 -0.38 0.12 6100 0.000 5267 0.000 6100 0.000 4251 0.000 2 30 62 01H 1

13 Repeat 0.12 23.0 13.9 0.61 -0.16 -0.04 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 30 62 01H 2

13 Repeat 0.09 20.0 13.3 0.45 0.03 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 30 67 02H 1

14 Repeat 0.34 73.0 53.5 2.90 -0.35 -0.01 6100 0.000 5231 0.000 6100 0.000 4414 0.000 2 31 37 03H 1

17 Repeat 0.22 42.0 28.6 0.88 -0.13 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 31 53 02H 1

13 Repeat 0.26 67.0 47.7 2.74 -0.29 -0.03 6100 0.000 5915 0.000 6100 0.000 5142 0.000 2 31 68 01H 1

14 Repeat 0.45 45.0 30.4 1.04 -0.23 0.22 6100 0.000 6100 0.000 6100 0.000 5815 0.000 2 32 30 02H 1

17 IDOD Repeat 0.31 67.0 52.7 1.34 -0.25 0.06 6100 0.000 5454 0.000 6100 0.000 4641 0.000 2 32 37 03H 1

17 Repeat 0.22 26.0 14.6 0.64 -0.05 0.17 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 32 44 04H 1

17 Repeat 0.31 45.0 28.3 1.23 -0.27 0.04 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 32 47 03H 1

13 Repeat 0.31 54.0 41.0 1.70 -0.32 -0.01 6100 0.000 6100 0.000 6100 0.000 5433 0.000 2 32 59 04H 1

13 Repeat 0.09 27.0 18.2 0.41 -0.13 -0.04 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 32 62 01H 1

13 Repeat 0.19 32.5 22.2 0.68 -0.08 0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 33 57 02H 1

13 Repeat 0.19 37.0 23.2 0.98 0.05 0.24 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 33 69 02H 1

14 Repeat 0.21 34.0 17.0 0.51 -0.18 0.03 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 33 71 02H 1

14 AONDB 4H >5v DNT Repeat 0.14 29.5 18.3 0.46 0.12 0.26 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 33 72 04H 1

14 Repeat 0.18 39.0 23.4 0.86 -0.09 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 34 36 03H 1

17 Repeat 0.28 45.0 32.5 1.12 -0.17 0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 34 42 02H 1

17 Repeat 0.13 20.0 13.8 0.48 0.02 0.15 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 34 47 02H 1

13 Repeat 0.16 42.0 32.4 1.32 0.01 0.17 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-24 PG&E Letter DCL-07-085 Table 5 - 1R14 PWSCC ARC Summary of Analysis Results Adjusted NDE Condition Monitoring Operational Assessment (WEC Model)

(ANL/TW Model)

Total Total Total Crack Length Max.

Avg.

FS Burst FS Length Length FS Burst FS Length Length SG R C TSP Depth Cal Plug reason Ind cat (in.)

Volts From To Pressure Leakage Burst Leakag Pressure Leakage Burst

(%)

(%)

psi gpm Press.

psi gpm Press.

ge psi gpm psi gpm 2 34 51 06H 1

13 Repeat 0.09 42.0 30.6 0.77 0.05 0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 3453 02H 1

13 Preventive lowOA burst C1 Repeat 0.51 83.0 57.9 3.15 -0.31 0.20 6100 0.000 4569 0.000 6100 0.000 3583 0.001 2 3453 02H 2

13 Preventive low OA burst C1 Repeat 0.28 39.0 27.5 1.28 -0.14 0.14 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 34 55 01H 1

13 Repeat 0.33 51.0 45.5 2.75 -0.34 -0.01 6100 0.000 5939 0.000 6100 0.000 5113 0.000 2 34358 02H 1

13 Repeat 0.33 60.0 47.0 2.05 -0.25 0.08 6100 0.000 5826 0.000 6100 0.000 4978 0.000 2 34 59 02H 1

13 Repeat 0.15 37.0 27.5 0.80 -0.05 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 34 65 02H 1

13 Repeat 0.12 20.0 12.6 0.55 -0.05 0.07 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 35 49 02H 1

13 Repeat 0.32 54.0 44.2 2.38 -0.18 0.14 6100 0.000 6100 0.000 6100 0.000 5239 0.000 2 35 52 03H 1

13 Repeat 0.26 31.5 24.2 1.10 -0.15 0.11 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 35 56 02H 1

13 Repeat 0.25 26.0 19.8 0.94 -0.05 0.20 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 35 70 02H 1

14 Repeat 0.22 51.0 33.3 1.24 -0.13 0.09 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 3660 04H 1

13 Repeat 0.19 64.0 35.1 1.39 -0.17 0.02 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 37 53 02H 1

13 Repeat 0.58 73.0 52.4 2.95 -0.35 0.23 6100 0.000 4936 0.000 6100 0.000 3818 0.000 2 37 68 03H 1

13 Repeat 0.16 28.0 17.3 0.57 -0.14 0.02 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 37 69 01H 1

14 Repeat 0.41 48.0 31.7 1.24 -0.27 0.14 6100 0.000 6100 0.000 6100 0.000 5776 0.000 2 37 69 01H 2

14 Repeat 0.32 46.5 34.5 1.75 0.04 0.36 6100 0.000 6100 0.000 6100 0.000 5816 0.000 2 37 69 03H 1

14 Repeat 0.27 28.0 14.5 0.76 0.01 0.28 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 37 70 01H 1

14 Repeat 0.35 64.0 51.8 2.65 -0.19 0.16 6100 0.000 5407 0.000 6100 0.000 4542 0.000 2 3773 03H 1

14 Repeat 0.25 37.0 28.3 0.96 -0.09 0.16 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 37 74 03H 1

14 Repeat 0.41 48.0 37.0 1.57 -0.17 0.24 6100 0.000 6100 0.000 6100 0.000 5392 0.000 2 38 66 01H 1

13 Repeat 0.26 51.0 36.3 1.08 0.02 0.28 6100 0.000 6100 0.000 6100 0.000 5921 0.000 2 39 73 02H 1

14 Repeat 0.31 28.0 20.4 0.97 -0.31 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2 39 73 02H 2

14 Repeat 0.25 48.0 39.1 1.70 0.03 0.28 6100 0.000 6100 0.000 6100 0.000 5828 0.000 2 43 49 03H 1

13 Repeat 0.30 51.0 40.6 1.62 -0.23 0.07 6100 0.000 6100 0.000 6100 0.000 5540 0.000 4 17 24 01H 1

16 Repeat 0.08 34.0 23.4 0.39 0.34 0.42 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 20 25 01H 1

16 Repeat 0.15 20.0 12.4 0.23 -0.72 -0.57 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 21 67 05H 1

39 Repeat 0.22 48.0 33.7 0.97 -0.21 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 2176 01H 1

17 Repeat 0.12 30.0 24.2 0.53 -0.13 -0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 21 84 01H 1

17 Repeat 0.15 39.5 30.3 0.74 -0.03 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 26 37 06H 1

39 Repeat 0.11 39.0 22.5 1.19 0.08 0.19 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 2858 02H 1

16 Repeat 0.08 24.0 14.4 0.16 0.04 0.12 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 35 36 02H 1

16 Repeat 0.14 20.0 10.60.40 0.14 0.28 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-25 PG&E Letter DCL-07-085 Table 5 - 1 R1 4 PWSCC ARC Summary of Analysis Results Adjusted NDE Condition Monitoring Operational Assessment (WEC Model)

(ANL/TW Model)

Total Total Total Total Avg Length Length ES Burst ES Length Length SG R C TSP Crack Cal Plug reason Ind cat Lengt Depth Vepth From To Pressure Leakage Burst Pre Dep(i.)th vot Pressure Leakgeaurs No.

(in.)%)MVolts psi gpm Press.

psi gpm Press.

psi gpm psi gpm 4 35 56 02H 1

16 Repeat 0.08 26.0 15.7 0.37 0.02 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 35 56 03H 1

16 Repeat 0.10 20.0 10.4 0.32 -0.28 -0.18 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 35 56 03H 2

16 Repeat 0.10 28.0 18.5 0.44 0.00 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 35 61 02H 1

16 Repeat 0.10 37.0 25.5 0.36 -0.10 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 38 46 06H 1

16 Repeat 0.07 20.0 11.1 0.20 -0.06 0.01 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 38 46 06H 2

16 Repeat 0.06 20.0 10.0 0.27 0.17 0.23 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 38 69 02H 1

39 Repeat 0.12 47.0 33.4 0.67 -0.02 0.10 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 38 72 01H 1

17 Repeat 0.10 34.0 21.7 0.51 0.25 0.35 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 39 48 03H 1

16 Repeat 0.20 26.0 15.5 0.38 0.07 0.27 6100 0.000 6100 0.000 6100 0.000 6100 0.000 4 39 58 01H 1

16 Repeat 0.28 57.0 43.1 1.33 0.07 0.35 6100 0.000 6100 0.000 6100 0.000 5414 0.000 4 46 42 01H 1

16 Repeat 0.28 37.0 19.9 0.47 -0.28 0.00 6100 0.000 6100 0.000 6100 0.000 6100 0.000 2-26 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior Prior WEC CM Crack In CM CM Cycle OA Cycle OA minus CM minus CM minus Length Max Average No.

(WEC) psi (ANpITW)

Prection Projection ANIiTW OA OA (in)

Depth (%)

Depth (%)

psi(WEC) psi OA (ANL/TW)

(WEC) psi 1

3 28 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-1.44 0.91 0.22 1

4 41 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02 4.32 5.86 0.15 1

14 28 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 5.04 4.20 0.06 1

15 16 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.07 0.00

-0.30 0.09 1

15 76 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 5.04 3.04 0.20 1

17 16 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.44 0.66 0.12 1

19 15 03H 1

Repeat 6100 6100 5594 5858 506 506 242

-0.01

-0.72

-0.06 0.20 1

20 28 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.05 5.04 4.41 0.24 1

20 29 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 1.44 2.47 0.14 1

20 33 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00 6.06 0.03 1

21 13 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 1.44 3.94 0.21 1

21 51 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 0.32 0.12 1

21 54 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.05 15.83 6.78 0.19 1

23 14 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.72 1.57 0.19 1

24 67 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04 11.51 7.95 0.33 1

25 57 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 8.63 11.12 0.16 1

27 75 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03 0.72

-1.02 0.03 1

29 37 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 5.04 8.68 0.17 1

30 21 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 2.88 3.39 0.10 1

30 59 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04

-0.72 0.79 0.14 1

30 67 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02

-9.35 3.26 0.22 1

34 24 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 5.04 9.06 0.12 1

34 24 03H 2

Repeat 6100 6100 6100 6100 0

0 0

0.04 10.79 8.70 0.10 1

35 59 03H 1

Repeat 6100 6100 5935 6100 165 165 0

0.01 0.72 2.32 0.38 1

38 41 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.72 6.39 0.22 1

39 57 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.05 1.44

-1.32 0.17 2

2 10 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 6.47 6.85 0.14 2-27 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Enclosure 2

PG&E Letter DCL-07-085 Total Length Burst Pressure CM versus CA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

PriorPir Prior WEC CM Crack CM CM Cycle OA Cycle OA minus CM minus CM minus Length Max Average No.

(WE(iAnL/DepProjection Cycle(%A minu SG R

C TSP No.

Ind cat (WEC) psi (ANiTW)

Projection Projection ANL/TW OAOA (in)

Depth (%)

Depth V

psi (ANpsWI (ANLTW)

(WEC) psi 2

2 28 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.08 4.32 2.71 0.06 2

2 76 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00

-0.21 0.08 2

2 78 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00

-0.19 0.04 2

2 79 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02 10.79 9.17 0.16 2

2 90 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03

-1.80

-5.35

-0.05 2

2 90 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 7.91 6.17 0.12 2

2 90 04H 2

Repeat 6100 6100 6100 6100 0

0 0

0.06

-2.88 1.32 0.06 2

2 92 05H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00 0.14 0.06 2

2 92 05H 2

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00

-0.84 0.10 2

2 92 05H 3

Repeat 6100 6100 6100 6100 0

0 0

-0.07 1.08 5.21 0.10 2

2 93 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 6.12 3.24 0.11 2

3 46 7C 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 3.60 4.60 0.05 2

4 54 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.32 1.80 0.09 2

4 57 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 1.06 0.02 2

4 84 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 2.16 3.78 0.04 2

5 66 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 0.25 0.03 2

5 77 05H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 1.44 3.73 0.20 2

5 78 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 3.60 4.21 0.11 2

5 93 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02

-0.72 0.93 0.33 2

6 55 7C 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 0.72 1.45 0.08 2

6 74 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00

-1.03 0.11 2

6 74 03H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.04 4.68 4.84 0.14 2

7 17 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 8.63 8.94 0.19 2

7 31 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.32 4.54 0.09 2

7 31 7C 1

Repeat 5217 4904 4624 4986 593 280 231 0.02 2.88 2.25 0.26 2

7 53 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.88 3.08 0.06 2

7 68 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 2.16

-0.80

-0.01 2

8 4

05H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.16 4.16 0.20 2-28 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Reoeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Enclosure 2

PG&E Letter DCL-07-085 Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior Pir Prior WEC CM Crack CM CM Cycle OA Cycle OA minus CM minus CM minus Length Max Average SG R

C TSP Crack Ind cat (CM psi (ANL/TW)

Projection Projection ANuTW OA OA (in)

Depth (%)

Depth (%)

volt No.

(WEC) p psi (ANL/TW)

Poecti AN (ANLLTW)

(WEC) psi2(WEC) psi OA 2

8 15 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 8.63 6.71 0.17 2

8 48 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04

-1.44 0.68 0.10 2

8 55 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.32 3.44 0.24 2

8 57 01H 1

Repeat 5729 5417 4823 5091 906 594 638

-0.01

-0.72 1.13 0.24 2

8 66 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-5.76

-3.03 0.21 2

8 82 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 0.80 0.06 2

8 93 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03 3.24 2.66 0.27 2

9 27 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.03 0.00 0.81 0.04 2

9 30 01H 1

Repeat 5340 5050 4889 5141 451 161 199 0.06 4.32 2.25 0.24 2

9 38 02H 1

Repeat 5727 5469 4837 5163 890 633 564

-0.03 0.00 0.57 0.15 2

9 45 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02 2.16

-1.23 0.12 2

9 53 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.05 2.16 1.88 0.09 2

9 56 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00 3.40 0.26 2

9 82 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 1.44 5.55 0.12 2

10 49 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 2.16

-0.14 0.04 2

10 62 01H 1

Repeat 6100 6100 5645 5800 455 455 300 0.01 0.72

-1.51 0.15 2

10 67 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-2.16 0.20 0.10 2

10 68 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.44 0.26 0.06 2

10 69 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 3.96 5.50 0.06 2

10 85 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.32 1.17 0.06 2

11 20 02H 1

Repeat 6100 6100 5615 5782 485 485 318

-0.02 2.16 1.50 0.08 2

11 45 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02

-5.76 0.61 0.13 2

11 66 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 7.19 9.11 0.04 2

11 71 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-0.72 0.48 0.07 2

11 71 01H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-2.16

-1.19 0.02 2

11 71 01H 3

Repeat 6100 6100 6100 6100 0

0 0

-0.01 1.44 1.80 0.01 2

11 71 01H 4

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 5.30 0.10 2

11 84 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-0.72

-0.32 0.27 2-29 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior SG R

C TSP Crack nd c CM Cycle OA PriOA WECuC CM minus CM minus Length Max Average volt No.

(WEC) psi (ANLpTW)

Projection Projection ANL/TW OA 0

(in)

Depth (%)

Depth (%)

psi(WEC) psi OA (ANL/TW)

(WEC) psi 2

11 87 01H 1

Repeat 5565 5355 4449 4724 1116 906 841

-0.02

-1.44

-2.62 0.25 2

13 34 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.03 4.32 0.97 0.09 2

13 44 01H 1

Repeat 6100 5907 5496 5619 604 411 481 0.02 2.16 1.41 0.22 2

13 60 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.03 0.72

-0.09 0.02 2

14 16 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 10.79 12.31 0.14 2

14 45 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 0.00 2.14 0.05 2

14 58 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 5.76 6.09 0.07 2

14 68 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00

-1.28 0.11 2

14 70 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.44 1.06

-0.01 2

14 74 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 4.68 4.20 0.10 2

16 12 05H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.03 7.91 5.78 0.06 2

16 59 02H 1

Repeat 5927 5754 6100 6100

-173

-346

-173 0.08 5.04 4.44 0.09 2

16 60 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-2.16

-0.70 0.04 2

16 82 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 2.16 1.39 0.04 2

16 82 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.07 7.91 11.06 0.06 2

16 85 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 2.16 5.32 0.09 2

16 87 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04

-0.72 0.53 0.15 2

16 88 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 3.60 2.57 0.14 2

16 88 02H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00

-3.71 0.06 2

17 9

06H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00

-1.14 0.01 2

17 54 01H 1

Repeat 5393 5244 5072 5252 322 172 141 0.01 4.32 4.15 0.30 2

17 59 01H 1

Repeat 6100 6100 5740 5919 360 360 181

-0.03 0.00 0.49 0.02 2

17 66 01H 1

Repeat 6100 6100 5608 5870 492 492 230 0.02 0.00

-0.36 0.09 2

17 67 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 16.55 3.74 0.06 2

17 88 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.03

-2.16

-1.94 0.16 2

17 88 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00

-0.23 0.18 2

18 64 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 0.72

-3.42 0.14 2

18 67 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03

-2.16 4.14 0.29 2-30 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Pir Prior WEC CM PrirCM Cycle OA CM CM minus CM minus Length Max Average SG R

C TSP Crc lnd cat CM MA~fW CyrectoQA leO iu O

AVl No.

(WEC) psi (ANpWs (ANLe" Proection ANLTW OAN O

(in)

Depth (%)

Depth (%)minus (WEC) psi OA (ANLITW)

(WEC) psi 2

19 34 02H 1

Repeat 6100 5825 5380 5711 720 446 389 0.01

-2.16 0.39 0.12 2

19 74 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 2.16 0.28 0.06 2

19 84 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.07 10.79 7.00 0.20 2

20 48 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02

-3.60

-0.94 0.02 2

20 77 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.44 1.57 0.06 2

21 38 01H 1

Repeat 6100 5880 5480 5638 620 400 462 0.01 2.16 1.42 0.22 2

21 57 01H 1

Repeat 6100 5950 5421 5658 679 529 442 0.03 2.88

-0.91

-0.04 2

21 60 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 6.12 4.32 0.00 2

21 65 02H 1

Repeat 6100 6100 5375 5696 725 725 404

-0.01 2.88

-1.61 0.09 2

22 42 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 2.16 0.63 0.01 2

22 55 03H 1

Repeat 6100 6100 5842 6100 258 258 0

0.04

-2.16 0.48 0.14 2

23 25 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.07

-3.60

-0.34 0.03 2

23 54 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 6.47 4.32 0.07 2

23 79 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.32 3.66 0.06 2

24 77 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 4.32 4.74 0.09 2

.25 17 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00 1.53 0.09 2

25 50 02H 1

Repeat 5551 5337 4842 5054 708 495 497 0.03 2.16 0.35 0.14 2

25 55 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-7.19

-2.82 0.04 2

25 79 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 11.51 7.83 0.29 2

25 79 02H 2

Repeat 6100 6100 6100 6100 0

0 0

0.01 12.23 8.17 0.53 2

25 85 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 4.68 5.81 0.19 2

25 87 04H 1

Repeat 6100 5850 5742 5862 358 108 238 0.03 3.60 3.03 0.21 2

26 22 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 6.47 2.16 0.12 2

26 39 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 6.47 5.78 0.09 2

26 73 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.44

-0.35 0.09 2

26 79 01H 1

Repeat 5672 5450 5363 5593 309 87 79 0.00 5.76 4.46 0.14 2

27 55 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 4.32 1.88 0.05 2

27 56 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.04 0.00 4.60

-0.10 2-31 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Enclosure 2

PG&E Letter DCL-07-085 Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior Crak CPrior WEC CM SG R

C TSP Ca (ANCM Cycle OA Cycle OA minus CM minus CM minus Length Max Average Volt N.c EC) cps (ANpTW)

Projection Projection ANL/TW OA OA (WEC) 2GC SP No (EC pi psi (ANL2TW)

(WEC) psi OA (ANLOTW)

(in)

Depth (%)

Depth (%)

Vo psi 2

27 63 02H 1

Repeat 5817 5753 5390 5496 427 363 321 0.01 5.04 2.06 0.43 2

27 63 02H 2

Repeat 6100 6100 5307 5787 793 793 313

-0.02 2.16

-3.15 0.10 2

27 64 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.10

-1.44

-4.90 0.07 2

27 65 02H 1

Repeat 5810 5578 5134 5410 676 444 400

-0.01

-0.72 1.32 0.40 2

27 67 01H 1

Repeat 6100 5887 5109 5387 991 777 713

-0.08 5.04 0.22 0.19 2

27 67 01H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.01 2.16 1.73 0.09 2

27 67 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 7.91 7.27 0.20 2

27 69 01H 1

Repeat 4682 4452 4801 5011

-118

-349

-329 0.05 10.79 6.87 0.11 2

27 69 01H 2

Repeat 6100 6100 6100 6100 0

0 0

0.01 5.76 5.82 0.11 2

27 72 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.16 4.63 0.00 2

27 72 02H 2

Repeat 6100 6100 6100 6100 0

0 0

0.02 0.00

-0.93

-0.01 2

28 47 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00

-1.44 2.01 0.12 2

28 66 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.16 3.95 0.12 2

29 51 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.05 0.72 1.29 0.05 2

29 66 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.07 0.72 3.82 0.15 2

30 56 01H 1

Repeat 5267 5007 4253 4571 1013 753 696

-0.02

-2.88

-0.64

-0.11 2

30 62 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 2.16 0.63 0.04 2

30 62 01H 2

Repeat 6100 6100 6100 6100 0

0 0

0.01 0.00 1.14 0.04 2

30 67 02H 1

Repeat 5231 5115 4737 4893 494 378 338 0.04 5.76 0.26 0.23 2

31 37 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 12.23 8.09 0.16 2

31 53 02H 1

Repeat 5915 5849 5294 5412 622 556 503

-0.01 2.16 0.32 0.10 2

31 68 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 10.07 6.43 0.08 2

32 30 02H 1

Repeat 5454 5322 5564 5742

-110

-241

-288

-0.01 11.51 8.49 0.27 2

32 37 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04 2.88 1.93 0.08 2

32 44 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03

-4.32

-3.14 0.06 2

32 47 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.06 2.16 1.31 0.04 2

32 59 04H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 2.88 1.07 0.07 2

32 62 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.06 3.24 2.29 0.06 2-32 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior Pir Prior WEC CM Crack CM ycle OA CCM minus CM minus Length Max Average SG R

TSP No.

Ind cat CM (ANL/TW)

Projection Cycle oA minus OA OA Volt (WC s

ALT)

Projection ANL/TW (AL--)

(E)

(n Det(%

Deh()

psi (ANL/w)

(WEC) psi OA (ANLTW)

(WEC) psi 2

33 57 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03

-3.60

-2.74 0.00 2

33 69 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.05

-5.76

-8.48 0.14 2

33 71 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03 6.83 3.75 0.08 2

33 72 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02 1.44 1.43 0.00 2

34 36 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03 10.79 8.73 0.17 2

34 42 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 0.00 1.90 0.04 2

34 47 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.02 0.00 3.16 0.14 2

34 51 06H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 4.32 4.86 0.11 2

34 53 02H 1

Repeat 4569 4282 4354 4627 215

-72

-58 0.04 7.19 5.02 0.40 2

34 53 02H 2

Repeat 6100 6100 6100 6100 0

0 0

0.05 7.91 6.97 0.22 2

34 55 01H 1

Repeat 5939 5807 5354 5544 585 453 395 0.01

-6.47 0.85 0.22 2

34 58 02H 1

Repeat 5826 5671 4944 5126 882 727 700 0.01

-5.76

-2.35 0.01 2

34 59 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.88 1.76 0.02 2

34 65 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01

-2.16

-2.25 0.06 2

35 49 02H 1

Repeat 6100 5925 5879 6100 221 46 0

0.04 4.32 3.98 0.31 2

35 52 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.52 4.92 0.09 2

35 56 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04

-9.35

-6.13 0.13 2

35 70 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 3.60 4.27 0.06 2

36 60 04H 1

Repeat 6100 6100 6100 6100 0

0 0

0.07 7.91 1.20 0.08 2

37 53 02H 1

Repeat 4936 4568 4197 4563 739 371 373

-0.01 6.47 2.36 0.41 2

37 68 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.06

-2.16

-3.07 0.10 2

37 69 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 1.44 4.20 0.14 2

37 69 01H 2

Repeat 6100 6100 6100 6100 0

0 0

0.01 4.68 4.53 0.10 2

37 69 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-2.16

-2.67

-0.01 2

37 70 01H 1

Repeat 5407 5252 4994 5207 413 258 200

-0.02 4.32 4.44 0.16 2

37 73 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 7.91 7.95 0.08 2

37 74 03H 1

Repeat 6100 6100 5611 5936 489 489 164 0.01 3.60 3.79 0.01 2

38 66 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04

-1.44 2.55 0.01 2-33 PG&E Letter DCL-07-085 Table 6 - PWSCC ARC Repeat Indications - Comparison of CM versus Prior Cycle OA Projections and Cycle 14 Growth Rates Total Length Burst Pressure CM versus OA Comparison (psi)

Growth Rate per EFPY (1.39 EFPY)

Prior Crak MPrior WEC CM Crc M

CM Cycle OA Cyl A

mns CM minus CM minus Length Max Average SG R

C TSP Cro.

Ind cat CM (ANL/TW)

Projection Cycle OA minus CMAiu CMAiu egh a

vrg Volt No.

(WEC) psi psi (ANL/TW)

Projection ANL/TW OA OA (in)

Depth (%)

Depth (%)

(WEC) psi OA (ANLTW)

(WEC) psi 2

39 73 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00

-3.60 1.70 0.17 2

39 73 02H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.02 0.00 3.06 0.20 2

43 49 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03 0.00 4.32 0.12 4

17 24 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-3.60

-1.89 0.04 4

20 25 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 3.65 0.01 4

21 67 05H 1

Repeat 6100 6100 6100 6100 0

0 0

0.03

-2.16

-0.94 0.16 4

21 76 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.05

-2.88 1.71

-0.08 4

21 84 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 1.80 1.45 0.04 4

26 37 06H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 9.35 2.22 0.22 4

28 58 02H 1

Repeat 6100 6100 6100 6100 0

0 0

0.01 2.88 2.03

-0.09 4

35 36 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.06 0.00 2.09 0.02 4

35 56 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 4.32 0.81 0.04 4

35 56 03H 1

Repeat 6100 6100 6100 6100 0

0 0

0.00 0.00 2.32 0.05 4

35 56 03H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.02 5.76 6.07 0.01 4

35 61 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 5.76 8.63 0.06 4

38 46 06H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.02 0.00

-1.75

-0.04 4

38 46 06H 2

Repeat 6100 6100 6100 6100 0

0 0

-0.02 0.00

-1.00

-0.06 4

38 69 02H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 10.07 6.36 0.08 4

38 72 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-2.88

-3.34 0.02 4

39 48 03H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01

-2.16 1.39 0.04 4

39 58 01H 1

Repeat 6100 6100 6100 6100 0

0 0

0.04 2.88 6.69 0.06 4

46 42 01H 1

Repeat 6100 6100 6100 6100 0

0 0

-0.01 7.19 4.31 0.05 2-34 PG&E Letter DCL-07-085 Table 7 - IR1 4 TSP Circumferential Indications Unadjusted NDE Adjusted NDE Adjusted for Upper Got aeprEP 95% NDE Uncertainty Got aeprEP Flaw Dent IDMixed Anle Max Avg Age Max Avg Age Max Avg Age Max Avg SG Rw ClTP Cak Eeain Volt Volt oD tblz Mode deg Det Det deg Depth Depth deg DphDepth deg Depth Depth Volt OD%

11 33 37 2H 1

0.03 0.91 4.95 ID 24.0 41.0 29.7 24.0 39.0 20.3 77.8 63.5 39.7 5.8 2.9

-1.2.

0.39 12 4

75 1H 1

0.33 0.17 20.31 OD Yes 37.9 98.0 65.0 37.9 76.0 61.4 176.1 90.7 69.8

-1.5

-7.1

-9.4 0.05 12 4

75 1H 2

0.42 0.14 20.31 OD Yes 30.3 69.0 54.5 30.3 60.0 48.3 173.0 79.0 61.6 1.7

-8.3

-7.6 0.00 12 5

75 1H 1

0.34 0.37 33.85 OD 53.1 42.0 27.5 53.1 45.0 33.2 182.4 68.0 52.2 15.2 0.0

-0.8 0.06 12 6

75 1H 1

0.35 0.21 16.48 OD 30.6 29.0 12.6 30.6 45.0 37.6 173.1 68.0 54.9

-6.8 0.0

-0.3 0.01 12 10 67 2H 1

0.14 0.23 5.24 OD 26.0 49.0 24.7 26.0 45.0 35.1 171.2 68.0 53.4 1.8 0.0 0.1 0.02 12 11 82 4H 1

0.29 0.14 10.25 OD 46.0 48.0 31.5 46.0 45.0 36.8 179.5 68.0 54.4 7.5 0.0

-0.7 0.01 12 19 68 1H 1

-0.19 0.2 8.68 OD Yes 42.1 57.0 43.7 42.1 49.0 38.1 177.9 70.9 55.3 5.0

-7.9

-6.1 0.06 12 19 68 1H 2

0.13 0.2 18.68 OD Yes 23.0 46.0 29.6 23.0 45.0 34.1 170.0 68.0 52.8 2.4 0.0 0.8 0.03 12 19 68 1 H 3

0.2 0.13 8.68 OD Yes 42.1 47.0 27.7 42.1 45.0 38.9 177.9 68.0 55.7 5.0

-1.4 1.1 0.01 12 24 40 1H 1

0.25 0.29 8.64 OD 44.0 29.0 15.0 44.0 45.0 37.0 178.6 68.0 54.6 23.3 0.0 5.1 0.06 12 24 40 1H 2

0.27 0.24 8.64 OD 36.0 50.0 30.8 36.0 49.0 38.9 175.3 70.9 55.7 11.9 2.9 3.8 0.06 12 32 77 4H 1

0.3 0.1 24.99 OD

.19.1 55.0 40.4 19.1 55.0 38.7 168.4 75.3 55.6 2.2 7.2 5.1 0.03 14 42 64 1H 1

0.3 0.26 11.61 OD Yes 74.4 76.0 57.4 74.4 66.0 51.0 191.2 83.3 63.3 22.9 12.2 12.7 0.06 Note 1: Growth rate based on adjusted NDE, not the uncertainty adjusted NDE.

Note 2: Location (inch) is relative to the centerline of the tube support plate.

Note 3: Tube stabilization determined per evaluation by Westinghouse.

Note 4: There were no mixed mode indications (combined circumferential and axial indications at same TSP).

2-35 PG&E Letter DCL-07-085 Table 8 PWSCC ARC Leak Rate Predictions SLB Leak Rate (gpm at room temperature)

Type of Monte Cycle CM or OA Carlo Analysis and SG 1-1 SG 1-2 SG 1-3 SG 1-4 Confidence Level EOC-14 Prior cycle Single Indication 0

0 NA 0

OA 95/95 EOC-14 Prior cycle Total SG 95/95 0

1.35 NA 0

OA (POD 0.6)

EOC-14 CM Single Indication 0

0 NA 0

95/50 EOC-14 CM Total SG 95/50 0

0 NA 0

(POD 1.0)

EOC-15 OA Single Indication 0

0 (Note 1)

NA 0

95/95 EOC-15 OA Total SG 9 0

2.14 NA 0

(POD 0.6)

Note 1: Single indication analyses projected a leak rate of 0.001 gpm for two indications in SG 1-2, for a total SG 1-2 leak rate of 0.002 gpm. However, these two indications were removed from service by tube plugging in 1R14, so the resulting single indication leak rate for SG 1-2 was 0 gpm.

2-36 PG&E Letter DCL-07-085 Table 9 Comparison of Frequencies of 1R14 New and Repeat Axial PWSCC Indications as a Function of Average Depth AD% TW Bin Frequency New Frequency Repeat Relative Percentage New vs Repeat 10 2

4 50%

15 4

35 11%

20 4

21 19%

25 2

35 6%

30 2

31 6%

35 1

26 4%

40 2

34 6%

45 0

9 0%

50 0

14 0%

55 0

6 0%

60 0

2 0%

Total 17 217 2-37 PG&E Letter DCL-07-085 Figure 1 DCPP Unit I TSP Circumferential Indications Average Depth (AD) Trending 70.0

.C 60.0 50.0 40.0 1 0 30.0 2 40.0 100 0.0 0

UU I

I a

1994 1995 1996 1997 1998 1999 2000 2001 Year Detected 2002 2003 2004 2005 2006 2007 2008 I

• AD 1997 to present

• AD 1995 -Linear (AD 1997 to present) 2-38

1.6 1.4-PG&E Letter DCL-07-085 Figure 2 DCPP Unit I TSP Circumferential Indications Plus Point Maximum Voltage Trending

$,--U-O0 1.2 E 1.0 E

)( 0.8 0.6 I.0 0.4 0,2 0.0 -

199 )4 1995 1996 1997 1998 1999 2000 2001 Year Detected 2002 2003 2004 2005 2006 2007 2008 I

• Max Volts 1997 to present a Max Volts 1995 -

Linear (Max Volts 1997 to present) I 2-39 PG&E Letter DCL-07-085 Figure 3 DCPP Unit 1 TSP PWSCC Mixed Mode - Circumferential Indications Average Depth and Maximum Volts Trending 40 35-30 -

e 25-S20-

• 15-10-5-

0-A A

0.6

- 0.5

.0.4

-0.3> x 0.2

-0.1 0

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Year Detected I n Average Depth A

Volts -

- Linear (Volts) I 2-40 PG&E Letter DCL-07-085 Figure 4 DCPP Unit I Number of New TSP Circumferential Indications 40 35 0

30 U

25 r

20 U

.~15 10 E

z 5

I I

Ml I

I 1995 1996 1997 1998 1999 2000 2001 Year Detected 2002 2003 2004 2005 2006 2007 1

0 Number of new U1 circ indications 2-41 PG&E Letter DCL-07-085 ENCLOSURE 3 AREVA REPORT 86-9055670-000 DCPP UNIT I R14 VOLTAGE-BASED ARC 90-DAY REPORT