ULNRC-06152, Response to Request for Additional Information Round 2 Application for Amendment to Facility Operating License Revision to Final Safety Analysis Report Standard Plant Section 3.6 for High Density Polyethylene Pipe Crack Exclusion

Response to Request for Additional Information Round 2 Application for Amendment to Facility Operating License Revision to Final Safety Analysis Report Standard Plant Section 3.6 for High Density Polyethylene Pipe Crack Exclusion

ML14345B052
Person / Time
Site:	Callaway
Issue date:	12/11/2014
From:	Maglio S Ameren Missouri
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LDCN 13-0016, TAC MF3202, ULNRC-06152
Download: ML14345B052 (16)

Text

~~

WAmeren MISSOURI Callaway Plant December 11, 2014 ULNRC-06152 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Ladies and Gentlemen:

10 CFR 50.90 DOCKET NUMBER 50-483 CALLAWAY PLANT UNIT 1 UNION ELECTRIC CO.

FACILITY OPERATING LICENSE NPF-30 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION ROUND 2 RE: APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NPF-30 REVISION TO FINAL SAFETY ANALYSIS REPORT STANDARD PLANT SECTION 3.6 FOR HIGH DENSITY POLYETHYLENE PIPE CRACK EXCLUSION (TAC NO. MF3202, LDCN 13-0016)

References:

1. ULNRC-06043 dated December 6, 2013, "Revision to FSAR Standard Plant Section 3.6 for HDPE Crack Exclusion (LDCN 13-0016)"

2. NRC Request for Additional Information, Carl F. Lyon (NRC) to Fadi Diya (Union Electric Company) dated July 1, 2014

3. ULNRC-0613 7 dated September 2, 2014, "Response to NRC Request for Additional Information Regarding Application for Amendment to Facility Operating License NPF-30 (TAC NO. MF3202, LDCN 13-0016) Revision to FSAR Standard Plant Section 3.6 for HDPE Crack Exclusion"

4. NRC Request for Additional Information Round 2, Carl F. Lyon (NRC) to Fadi Diya (Union Electric Company) dated October 28,2014 In Reference 1 above, Ameren Missouri (Union Electric Company) submitted an application for amendment to Facility Operating License Number NPF-30 for the Callaway Plant. The proposed amendment would add a new pipe crack exclusion allowance to FSAR Standard Plant Section 3.6.2.1.2.4, "ASME Section III and Non-Nuclear Piping-Moderate-Energy," and FSAR Standard Plant Table 3.6-2, "Design Comparison to Regulatory Positions of Regulatory Guide 1.46, Revision 0, dated May 1973, titled 'Protection Against Pipe Whip Inside Containment,'" for the high density polyethylene (HDPE) piping installed in ASME Class 3 line segments of the essential service water (ESW) system. The amendment was submitted per the requirements of 10 CFR 50.59(c)(2)(viii).

PO Box 620 Fulton, MD 65251 AmerenMissouri.com STARS

• Alliance

ULNRC-06152 December 11, 2014 Page2 In Reference 2 above, the NRC requested additional information to complete their review, which was provided by Ameren Missouri in Reference 3. In Reference 4 above, the NRC issued a second request for additional information. The attachment to this letter provides the requested information.

No commitments are contained in this letter. If you have any questions on this amendment application, please contact me at (573) 676-8719 or Mr. Jim Kovar at (314) 225-1478.

I declare under penalty of perjury that the foregoing is true and correct.

Sincerely, Executed on: l 2/ l ( /lD l Lf L\\~4wY Scott Maglio Manager, Regulatory Affairs JPK/nls

Attachment:

RAI Response

Enclosure:

RAI 9(b)

ULNRC-06152 December 11, 2014 Page 3 cc:

Mr. Marc L. Dapas Regional Administrator U.S. Nuclear Regulatory Commission Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Fred Lyon Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 0-8B 1 Washington, DC 20555-2738

ULNRC-06152 December 11, 2014 Page4 Index and send hardcopy to QA File A160.0761 Hardcopy:

Certrec Corporation 4150 International Plaza Suite 820 Fort Worth, TX 76109 (Certrec receives ALL attachments as long as they are non-safeguards and may be publicly disclosed.)

Electronic distribution for the following can be made via Responses and Reports ULNRC Distribution:

F. M. Diya D. W. Neterer L. H. Graessle T. E. Herrmann B.L.Cox S. A. Maglio T. B. Elwood Corporate Communications NSRB Secretary STARS Regulatory Affairs Mr. John O'Neill (Pillsbury Winthrop Shaw Pittman LLP)

Ms. Leanne Tippett-Mosby (DNR)

Attachment to ULNRC-06152 ATTACHMENT RAI RESPONSE

Attachment to ULNRC-06152

Reference:

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO REVISE FSAR-SP 3.6 UNION ELECTRIC COMPANY CALLAWAY PLANT, UNIT 1 DOCKET NO. 50-483

1. Letter No. ULNRC-06043, from Scott Maglio, Regulatory Affairs Manager, Ameren Missouri, to U. S. Nuclear Regulatory Commission, Document Control Desk, "Revision to FSAR Standard Plant Sections 3.6 for HOPE Crack Exclusion," December 6, 2013. (ML13340A775)

2. Letter No. ULNRC-06137, from Scott Maglio, Regulatory Affairs Manager, Ameren Missouri, to U. S. Nuclear Regulatory Commission, Document Control Desk, "Response to NRC Request for Additional Information Regarding Application for Amendment, Revision to FSAR Standard Plant Sections 3.6 for HOPE Crack Exclusion," September 2, 2014. (ML14245A653)

By application dated December 6, 2013 (Reference 1 ), as supplemented by letter dated September 2, 2014 (Reference 2), to the U.S. Nuclear Regulatory Commission (NRC), Union Electric Company (dba Ameren Missouri, the licensee) submitted a license amendment request (LAR) to revise the Final Safety Analysis Report-Standard Plant (FSAR-SP) Section 3.6.2.1.2.4, "ASME [American Society of Mechanical Engineers] Section Ill and Non-Nuclear Piping - Moderate-Energy," to include a new pipe crack exclusion allowance at Callaway Plant, Unit 1.

The NRC staff has determined that the additional information requested below is needed to complete its review.

Mechanical and Civil Engineering Branch (EMCB) - RAI-9 The response to RAI-8 of Reference 2 contains Table 1 on page 10 of 10 of Reference 2: The NRC requests the licensee to provide the following additional information.

(a) Please clarify whether the computed stresses and the crack postulation threshold limits in Table 1 are for the ASME Class 3 High Density Polyethylene (HOPE) moderate-energy piping (not the buried portion, that is, the portion between the buried portion and the metallic piping interface) in the Control Building basement, and in the Ultimate Heat Sink (UHS) Penetration Room.

Response

The computed stresses and crack threshold limits in Table 1 (page 10 of 10 of the Attachment included in Reference 2) are for the short sections of Class 3, safety-related HOPE that are not buried. These sections are located between the buried portions and the metallic interfaces.

The computed stresses and crack postulation threshold limits in Table 1 are not for the buried HOPE piping. The portions of HOPE piping that are not buried are located in the Control Building basement, the Ultimate Heat Sink (UHS) Penetration Rooms, and the ESW Yard Vault.

These are the same locations where the metallic interfaces occur and a moderate-energy pipe crack is still postulated for the metallic piping for the Internal Flooding Analysis. The scope of this request is limited to the HOPE piping that is not buried and is located in the Control Building basement and the UHS Cooling Tower. The basis for excluding the HOPE piping in the yard vault is contained in the response to Question 3 of the NRC's July 1, 2014 RAI, as documented in Reference 2.

1

Attachment to ULNRC-06152 (b) The computed stresses in Table 1 include stresses based on ASME equations 9b and 10.

Please clarify if the equation 9b portion of the stresses includes contributions from axial force and the moment from dead weight (non-buried portion of HOPE piping) in addition to those from pressure, the Operating Basis Earthquake (OBE), and seismic anchor movement (SAM).

Further, pages 4 of 15 through 14 of 15 of attachment 4, Section 5 of Reference 1 mention pressure, OBE, and SAM, but do not mention dead weight. If the contribution from dead weight is not included, please explain the rationale.

Response

The HOPE piping is not designed using the Code Equations from ASME Section Ill. It is installed in an ASME Section Ill, Class 3 system. The design was approved by the NRC in Relief Request 13R-1 0. The approved design principals are contained in Callaway procedure APA-ZZ-00662 Appendix F and follow those contained in Code Case N-755-1. Note that the use of Code Case N-755-1 was not part of the relief request. As stated above, APA-ZZ-00662 Appendix F contains the design principles for the HOPE pipe.

The Service Level 8 Longitudinal Stress Equation, as defined in APA-ZZ-00662 Appendix F, does not include contribution due to dead weight as defined in ASME Section Ill Subsection ND-3652.

The impact due to including dead weight, in addition to the APA-ZZ-00662 Appendix F loads, is calculated in an Enclosure to this response. The dead weight loads from calculations EF-119 Rev. 0, EF-120 Rev. 0, 2007-18082 Rev. 2, 2007-18083 Rev. 1, and 2007-16601 Rev. 1 were incorporated into the axial force (Fa) and the moment (M) for the Service Level 8 Longitudinal Stress equation as defined in calculation 2007-16760 Rev. 2 Add. 2. A summary of the results for the sum of Service Level 8 Longitudinal Stress (Eq. 9b) and the Alternative Thermal Expansion or Contraction Stress (Eq. 1 0) is contained below.

Computed Computed Crack Margin Stress (w/o Stress (with Postulation (w/o Line Number Description Location Dead Dead Threshold Dead Weight)

Weight) limit Weight)

(psi)

(psi)

(psi)

(psi)

EF-003-AZC-36" A Train Control Building 673.26 693.83 773.6 100.34 Supply Basement EF-007-AZC-36" B Train Control Building 717.48 730.62 773.6 56.12 Supply Basement E F-083-AZC-36" A Train Control Building 300.58 326.15 734.2 433.62 Return Basement EF-140-AZC-36" B Train Control Building 441.04 449.38 734.2 293.16 Return Basement EF-083-AZC-36" A Train UHS Penetration 236.06 267.29 734.2 498.14 Return Room E F-140-AZC-36" B Train UHS Penetration 236.06 267.29 734.2 498.14 Return Room 2

Margin (with Dead Weight)

(psi) 79.77 42.98 408.05 284.82 466.91 466.91

Attachment to ULNRC-06152 The impact of including dead weight increases the Service Level B Longitudinal Stress by 20.57 psi for the A Train Supply line and by 13.14 psi for the B Train Supply line, which are the most limiting locations. The stresses at all locations remain below the crack postulation threshold limit.

(c) Table 1 (Page 10 of 10 in Attachment 1 of Reference 2) shows a temperature of 175°F as the thermal mode analyzed for the Essential Service Water (ESW) return trains in the Control Room basement and UHS Penetration Room. The Equation 10 portion of computed stresses for the return trains therefore includes 175°F thermal mode. Please clarify if the Equation 9b allowable stress (Sh) used in the crack postulation threshold limit for HDPE corresponds to the allowable stress at 175°F. In case Sh at 175°F is not used, please explain the rationale.

Response

The Service Level B Longitudinal Stress Equation for the upset condition (Equation 9b) and the Crack Postulation Threshold Limit do not use a water temperature of 175°F for the ESW return lines in the Control Building basement and the UHS Penetration Rooms.

All the variables in the Service Level B Longitudinal Stress Equation are independent of design temperature. The axial force (Fa) and the resultant bending moment (M) in the Service Level B Longitudinal Stress Equation (Eq. 9b), as defined in APA-ZZ-00662 Appendix F, are due to mechanical loads and do not include forces and moments due to thermal expansion. The Service Level B Longitudinal Stress Equation is not directly compared to an allowable stress.

The output of the Service Level B Longitudinal Stress Equation is added to the output of the Alternative Thermal Expansion or Contraction Equation and compared to an allowable stress value defined in both Branch Technical Position (BTP) MEB 3-1 and FSAR Section 3.6.2.1.2.4(c) for piping design to ASME Section Ill. This is equivalent to the moderate energy crack exclusion described in Branch Technical Position (BTP) MEB 3-1, and contained in FSAR Section 3.6.2.1.2.4(c) that is applicable to Class 2 and 3 piping designed to ASME Section Ill.

The HOPE piping is designed to APA-ZZ-00662 Appendix F and not to ASME Section Ill, so the moderate energy crack exclusion does not directly apply.

As stated in Calculation 2007-16760 Rev. 2 Add. 2 page 3 and Callaway FSAR Section 3.6.1.1 (d), when a leakage crack in moderate-energy fluid system piping is postulated, each crack is considered separately as a single postulated initial event occurring during normal plant conditions.

Thus, the allowable stresses used to calculate the Crack Postulation Threshold Limit for the supply and return lines are based on normal operating conditions, as opposed to those present during a design basis event. The allowable stress used for the return lines is 613 psi based on an operating temperature of 113°F, which is greater than the maximum allowable temperature for water returning to the pond during normal operating conditions. The 175°F return temperature would result from a Loss of Coolant Accident (LOCA) and would not occur during normal operations.

As described in calculation 2007-16760 Rev. 2 Add. 2 page 3, the Alternative Thermal Expansion or Contraction Stress (Eq. 1 0) in this license amendment request uses the maximum allowed normal operating conditions for A Train return line in the Control Building Basement, as well as, the A and B Train Return Lines in the UHS Cooling Tower Penetration Rooms. The B Train return line in the Control Building basement uses LOCA temperatures as described in 3

Attachment to ULNRC-06152 calculation 2007-16760 Rev. 2 Add. 2 page 10-11. Calculations 2007-16760 Rev. 2, 2007-18082 Rev. 2, 2007-18083 Rev. 1, and 2007-16601 Rev. 1 evaluate the higher thermal expansions due to a LOCA as part of the design basis for the piping. However, they were not incorporated into the Crack Postulation Threshold Limit since a moderate energy crack is postulated during normal operating conditions and not coincident with a LOCA. The Thermal Mode Analyzed Column of Table 1 (page 10 of 10 in Attachment 1 of Reference 2) is corrected and contained in the last page of this response. Note that these values do not include dead weight. See the Enclosure to this response for values that include dead weight.

(d) Provide a brief discussion related to the fire hazard of the non-buried sections of the HOPE piping in the Control Building Basement, in the Ultimate Heat Sink (UHS) Penetration Room, and in the yard vault on any safety related commodities in the vicinity. Please also address fire resistance characteristics of the insulation, and any wrapping used on the HOPE piping.

Response

HOPE Pipe Fire Hazard The HOPE pipe which is composed of high density polyethylene is considered a combustible material; however; its ignition temperature is >300 degrees C and auto-ignition temperature is 349 degrees C. If ignited, HOPE pipe will create dense smoke. The exposed HOPE pipe fire hazard could be considered comparable to electrical cable trays filled with IEEE rated electrical cables which are used throughout the plant in terms of its susceptibility to ignition and its smoke generation should it be ignited. The HOPE pipe is not an ignition source, and its addition does not affect the probability of a fire occurring in any fire area.

Control Building Basement In the Control Building 1974 elevation room 3101, ESW Pipe Space, both trains of ESW piping have approximately 2' of HOPE material terminating inside the room for both the ESW supply and return lines, so there are 4 terminations that are 2' in length. The four HOPE pipe terminations are located such that they are not subject to fire damage from any fixed ignition sources or the postulated transient ignition sources. Additionally, based on fire modeling, a hot gas layer is not postulated in room 3101. In this fire area the HOPE pipe has been evaluated and it does not present a fire hazard to the two trains of ESW equipment in the fire area.

UHS Penetration Room The ESW HOPE piping at the UHS Cooling Tower is separated into two separate fire areas that are train-related, UNCT, "Ultimate Heat Sink Cooling Tower A", and USCT, "Ultimate Heat Sink Cooling Tower B," which are separated by rated fire barriers. Fire damage is evaluated in these two fire areas as whole room burn-up; therefore, the inclusion of the HOPE pipe has no impact on the fire damage assumed for the safety related equipment.

Yard Vault The ESW HOPE piping in the yard vaults is ESW train specific and separated by rated fire barriers. There are no fixed ignition sources in the vaults, and fire damage is evaluated as whole room burn-up; therefore, the inclusion of the HOPE pipe has no impact on the fire damage assumed for the safety related equipment.

Resistance Characteristics No insulation or fire barrier materials are used on the exposed HOPE ESW pipe sections.

4

Attachment to ULNRC-06152 Table 1 Thermal Crack Design Maximum Design Mode Computed Postulation Margin Description Location Pressure Pressure Temperature Analyzed Stress Threshold (psi)

(psig)

(psig)

(oF)

(oF)

(psi) limit (psi)

I A Train Control Building I

190 190 95 95 673.26 773.6 100.34 Supply Basement B Train Supply Control Building 190 190 95 95 717.48 773.6 56.12 Basement A Train Control Building 45 45 175 113 300.58 734.2 433.62 Return Basement B Train Control Building 45 45 175 175 441.04 734.2 293.16 Return Basement A Train UHS Penetration 45 45 175 113 236.06 734.2 498.14 Return Room B Train UHS Penetration 45 45 175 113 236.06 734.2 498.14 Return Room

==

Conclusion:==

The sum of the Service Level 8 Longitudinal Stress and the Alternative Thermal Expansion or Contraction Stress (Computed Stress column) is less than the Crack Postulation Threshold for all locations. The Crack Postulation Threshold is equivalent to the moderate-energy pipe-break stress limit for ASME Section Ill design equations listed in NRC MEB 3-1 Section B.2.b and Callaway FSAR Section 3.6.2.1.2.4.

5

Enclosure to ULNRC-06152 ENCLOSURE RAI 9(b)

Enclosure to ULNRC-06152 RAI 9(b) Enclosure Evaluation:

This enclosure will incorporate the dead weight loads from calculations EF-119 Rev. 0, EF-120 Rev. 0, 2007-18082 Rev. 2, 2007-18083 Rev. 1, and 2007-16601 Rev. 1 into the Service Level B Longitudinal Stress calculation. The Service Level B Longitudinal Stress equation is defined in APA-ZZ-00662 Appendix F, which was approved by Relief Request I3R-10, and does not include a component for dead weight stress. This enclosure will incorporate dead weight stresses into the short sections of HDPE piping located in the Control Building Basement and the UHS Cooling Tower.

ESW Supply Line Analysis-Control Building Basement:

The crack threshold limit is 773.6 psi for the ESW Supply lines located in the Control Building Basement per calculation 2007-16760 Rev. 2 Add. 2.

For the seismic load case the term Fa is the absolute sum of the dead weight axial stress value, the OBE axial stress value, and the square-root-sum-of-the-square (SRSS) of the X, Y, and Z SAM values (in that order), which can be found in EF-119 Rev. 0 for node 120 (A Train) and EF-120 Rev. 0 for node 40 (B Train). The stresses for both trains were calculated and reviewed against moderate energy crack criteria.

FaATrain =1393+1466+.J245 2 +28 2 +1091 2 =3978lb FaBTrain = 1979+1204+.J66 2 +29 2 +1243 2 = 4428lb The moment, M, is found by first calculating the individual moments, which are the absolute sums of the dead weight case values, the OBE case values, and the SRSS of the X, Y, and Z SAM case values. The resultant moment is the SRSS of the individual moment values.

Individual Moment Values M XATrain = 2281 + 8090 + 2367 = 12738Jt *lb M YATrain = 3229 + 15360 + 1354 = 19943 ft *lb M ZATrain = 228 + 552 +53 = 833 jt *lb M XBTrain = 619 + 3087 + 3128 = 6834/t *lb M YBTrain = 1756 + 17714 + 841 = 20311.fi *lb M ZBTrain = 17 + 629 + 49 =695ft *lb Resultant Moment Values M ATrain =.J12738 2 + 19943 2 + 833 2 = 23678.6.fi *lb = 284142.6in *lb M BTrain =.J6834 2 + 20311 2 + 695 2 = 21441.2.fi *lb = 257293.9in *lb 1

Enclosure to ULNRC-06152 Next, the Service Level B Longitudinal Stress can be calculated for each train.

A Train Supply 0.5x 190x36 +2x0.5x 3978 +l.Ox284142.6 =563.13 si 2 X 3.789 383.42 2800.87 p

B Train Supply 0.5 X 190 X 36 + 2 X 0.5 X 4428 + 1.0 X 257293.9 = 554.72 si 2 X 3.789 383.42 2800.87 p

Note the minimum wall thickness is used as opposed to the nominal wall thickness to calculate the cross-sectional area and section modulus, which adds conservatism to the results.

The Alternative Thermal Expansion or Contraction Stress for the ESW supply lines in the Control Building Basement is taken from calculation 2007-16760 Rev. 2 Add. 2 and is shown below.

A Train Supply 1.0 x 291939 + 10158 = 130.7 si 2800.87 383.42 p

B Train Supply 1.0 x 398571 + 12888 = 175.9 si 2800.87 383.42 p

The Service Level B Longitudinal Stress must be added to the Alternative Thermal Expansion or Contraction Stress.

A Train Supply 563.13+130.7 = 693.83psi B Train Supply 554.72 + 175.9 = 730.62psi The sum of the Service Level B Longitudinal Stress and Alternative Thermal Expansion or Contraction Stress is 693.83 psi for the A Train ESW Supply piping and 730.62 psi for the B Train ESW Supply piping. This is less than the equivalent moderate energy pipe break stress limit for the HDPE piping in the ESW supply lines, which is 773.6 psi. Therefore, a moderate energy crack is not required to be postulated on the ESW HDPE Supply piping in Room 3101.

ESW Return Line Analvsis-Control Building Basement:

The crack threshold limit is 734.2 psi for the ESW Return lines located in the Control Building Basement per calculation 2007-16760 Rev. 2 Add. 2.

2

Enclosure to ULNRC-06152 For the seismic load case the term Fa is the absolute sum of the dead weight axial stress value, the OBE axial stress value, and the square-root-sum-of-the-square (SRSS) of the X, Y, and Z SAM values (in that order), which can be found in 2007-18082 Rev. 2 for node 3 (A Train) and 2007-18083 Rev. 1 for node 5 (B Train). The stresses for both trains were calculated and reviewed against moderate energy crack criteria.

F aATrain = 1858 + 6729 +.J48 2 + 65 2 + 338 2 = 8935lb FaBTrain = 2488 + 2418 +.J0 2 + 78 2 + 416 2 = 5329lb The moment, M, is found by first calculating the individual moments, which are the absolute sums of the dead weight case values, the OBE case values, and the SRSS of the X, Y, and Z SAM case values. The resultant moment is the SRSS of the individual moment values.

Individual Moment Values M XATrain = 3524 + 7474 +.J79 2 + 211 2 + 587 2 = 11627 ft *lb MYATrain =3423+11755+.J218 2 +60 2 +277 2 =15536ft*lb M ZATrain = 259 + 655 +.J10 2 +5 2 + 1 2 =925ft *lb M XBTrain = 200 + 3497 +.J0 2 + 296 2 + 883 2 = 4628/t *lb M YBTrain = 389 + 13781 +.J242 2 +5 2 + 2 2 = 14412/t *lb M ZBTrain = 18 + 673 +.J11 2 + 0 2 + 0 2 = 702ft *lb Resultant Moment Values M ATrain =.J11627 2 + 15536 2 + 925 2 = 19427.0ft *lb = 233124.5in *lb MBTrain =.J4628 2 + 14412 2 + 702 2 = 15153.1/t *lb = 181837.4in *lb Next, the Service Level B Longitudinal Stress can be calculated for each train.

A Train CB Return 0.5x 45x36 +2x0.5x 8935 +l.Ox233124.5 =213.42 si 2 X 3.789 383.42 2800.87 p

B Train CB Return 0.5x 45x36 +2x0.5x 5329 +l.Ox181837.4 =185.71 si 2 X 3.789 383.42 2800.87 p

Note the minimum wall thickness is used as opposed to the nominal wall thickness to calculate the cross-sectional area and section modulus, which adds conservatism to the results.

3

Enclosure to ULNRC-06152 The Alternative Thermal Expansion or Contraction Stress for the ESW return lines in the Control Building Basement is taken from calculation 2007-16760 Rev. 2 Add. 2 and is shown below.

A Train CB Return 1.0 x 241462 + 10170 = 112.73 si 2800.87 383.42 p

B Train CB Return l.Ox577956 + 21980 = 263.67 si 2800.87 383.42 p

The Service Level B Longitudinal Stress must be added to the Alternative Thermal Expansion or Contraction Stress.

A Train CB Return 213.42 + 112.73 = 326.15 psi B Train CB Return 185.71 + 263.67 = 449.38psi The sum of the Service Level B Longitudinal Stress and Alternative Thermal Expansion or Contraction Stress is 326.15 psi for the A Train ESW Return piping and 449.3 8 psi for the B Train ESW Return piping. This is less than the equivalent moderate energy pipe break stress limit for the HDPE piping in the ESW return lines, which is 734.2 psi. Therefore, a moderate energy crack is not required to be postulated on the ESW HDPE Return piping in Room 3101.

ESW Return Line Analvsis-Ultimate Heat Sink Cooling Tower The crack threshold limit is 734.2 psi for the ESW Return lines located in the Ultimate Heat Sink Cooling Tower per calculation 2007-16760 Rev. 2 Add. 2.

For the seismic load case the term Fa is the absolute sum of the dead weight axial stress value and the OBE axial stress value, which can be found in calculation 2007-16601 Rev. 1 for node 105.

Note that seismic anchor movements are considered negligible and are not included in the model per Section 3.1 of 2007-16601. Per 2007-16601 the A and B Train piping is symmetric and only the A Train piping is analyzed. The stresses calculated below will bound both trains and will be reviewed against moderate energy crack criteria.

Fa= 537 +3133 = 3610lb The moment, M, is found by first calculating the individual moments, which are the absolute sum of the dead weight and OBE case values since SAM is negligible. The resultant moment is the SRSS of the individual moment values.

4

Enclosure to ULNRC-06152 Individual Moment Values Mx = 64+561 =625ft *lb Mr = 587 + 2235 = 2822ft *lb M 2 = 7152 + 4617 = 11769ft *lb Resultant Moment Values M =.J625 2 + 2822 2 + 117692 = 12118.7 ft *lb = 145424.8in *lb Next, the Service Level B Longitudinal Stress can be calculated using the same philosophy as that used for the return lines in Room 3101 of the Control Building.

A and B Train UHS Return O.S X 45 X 36 + 2 X O.S X 3670 + l.O X 145424.8 = 168.4 si 2 X 3.789 383.42 2800.87 p

Note the minimum wall thickness is used as the nominal wall thickness to calculate the cross-sectional area and section modulus, which adds conservatism to the results.

The Alternative Thermal Expansion or Contraction Stress for the ESW return lines in the Control Building Basement is taken from calculation 2007-16760 Rev. 2 Add. 2 and is shown below.

A and B Train UHS Return 1.0 x 170658 + 14555 = 98.89 si 2800.87 383.42 p

The Service Level B Longitudinal Stress must be added to the Alternative Thermal Expansion or Contraction Stress.

A and B Train UHS Return 168.4 + 98.89 = 267.29 psi The sum of the Service Level B Longitudinal Stress and Alternative Thermal Expansion or Contraction Stress is 267.29 psi for the ESW Return piping in the UHS Cooling Tower. This is less than the equivalent moderate energy pipe break stress limit for the HDPE piping in the ESW return lines, which is 734.2 psi. Therefore, a moderate energy crack is not required to be postulated on the ESW HDPE Return piping in the UHS Cooling Tower.

5