ML19329A287

Subsequent License Renewal Application (SLRA) Supplement to Subsequent License Renewal Application Change Notice 6

ML19329A287
Person / Time
Site:	Surry
Issue date:	11/19/2019
From:	Mark D. Sartain Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
19-468
Download: ML19329A287 (16)

Text

Vm.GINIA ELEcrruc AND POWER CoMPANY RICHMOND, VIRGINIA 23261 November 19, 2019 10 CFR 50 10 CFR 51 10 CFR 54 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Serial Nos.:

19-468 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION (SPS) UNITS 1 AND 2 NRNDEA:

RO' Docket Nos.:

50-280/281 License Nos.: DPR-32/37 SUBSEQUENT LICENSE RENEWAL APPLICATION (SLRA)

SUPPLEMENT TO SUBSEQUENT LICENSE RENEWAL APPLICATION CHANGE NOTICE 6 On October 31, 2019, Dominion provided Change Notice 5 to the Surry Power Station (SPS) Units 1 and 2 Subsequent License Renewal Application (SLRA) to the NRC (Serial No.19-438) (ADAMS Accession No. ML19310E716).

. On November 7, 2019, in an email from Angela Wu (NRC) to Paul Aitken (Dominion),

the NRC provided six comments on Dominion's October 31, 2019 submittal. During a follow-up telecom between Dominion and NRC that same day, it was determined that no action was required on behalf of Dominion for comments 1, 3, and 4.

Subsequently, on November 13, 2019, in an email from Lauren Gibson (NRC) to Paul Aitken (Dominion), the NRC provided three draft RAls (comments 2, 5 and 6 from the email dated November 7, 2019) for which a response was requested 'On the docket.

Add~ionally, on October 14, 2019 Dominion submitted letter Serial No.19-385 which contained four topics that required an SLRA supplement. Change #1 in Enclosure 2 of letter Serial No.19-385 addressed ASME Code Case N-871 and examination of the accessible surfaces of the carbon fiber reinforced piping (CFRP) lining at the terminal ends. For clarity, it should be noted that the following sentence in Change #1 only applies to the tem,inal ends and not to the piping:

"Prior to installation of the existing CFRP lining, the exposed metallic substrate was ultrasonically examined to confirm the minimum wall thickness requirements specified in the design documents were met."

Serial Nos.19-468 Docket Nos. 50-280/281 Change Notice 6 Page 2 of 7 Change Notice 6, provided in Enclosure 1, includes responses to the three draft RAls. contains SLRA mark-ups that are a result of Change Notice 6, as described in Enclosure 1. This information was previously transmitted in an email from Mark Sartain (Dominion) to Angela Wu (NRG) on November 15, 2019.

If you have any questions or require additional information regarding this submittal, please contact Mr. Paul Aitken at (804) 273-2818.

Sincerely, Mark D. Sartain Vice President - Nuclear Engineering and Fleet Support COMMONWEAL TH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mark D. Sartain, who 1s Vice President - Nuclear Operations and Fleet Support of V1rg1nia Electric and Power Company He has affim,ed before me that he is duly authonzed to execute and file the foregoing document m behalf of that Company, and that the statements in the document are true to the best of his knowledge and belief Acknowledged before me this /'l-11, day of Je,./ert\\b..r,:, 2019 My Commission Expires* 4,Y:*.t !:>l,

GARY DON MILLER Notary Public Commonwealth of Virginia Reg. # 7629412 My Commission Explr88 August 31, 2(@

Commitments made in this letter: None

Enclosures:

1. Response to Draft RAls - Change Notice 6

2. SLRA Mark-ups - Change Notice 6

cc:

(w/o Enclosures except *)

U.S. Nuclear Regulatory Commission, Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, Georgia 30303-1257 NRC Senior Resident Inspector Surry Power Station Ms. Lauren Gibson

• NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop O 11 F1 11555 Rockville Pike Rockville, Maryland 20852-2738 Ms. Angela Wu*

NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop O 11 F1 11555 Rockville Pike Rockville, Maryland 20852-2738 Mr. Tam Tran

• NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop O 11 F1 11555 Rockville Pike Rockville, Maryland 20852-2738 Serial Nos.19-468 Docket Nos. 50-280/281 Change Notice 6 Page 3 of 7

Mr. G. Edward Miller NRC Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 0-9E3 11555 Rockville Pike Rockville, Maryland 20852-2738 Mr. Vaughn Thomas NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mail Stop O 4F12 11555 Rockville Pike Rockville, Maryland 20852-2738 State Health Commissioner Virginia Department of Health James Madison Building - 7th Floor 109 Governor Street Room 730 Richmond, Virginia 23219 Mr. David K. Paylor, Director Virginia Department of Environmental Quality P.O. Box 1105 Richmond, VA 23218 Ms. Melanie D. Davenport, Director Water Pennitting Division Virginia Department of Environmental Quality P.O. Box 1105 Richmond, VA 23218 Ms. Bettina Rayfield, Manager Office of Environmental Impact Review Virginia Department of Environmental Quality P.O. Box 1105 Richmond, VA 23218 Serial Nos.19-468 Docket Nos. 50-280/281 Change Notice 6 Page 4 of 7

Mr. Michael Dowd, Director Air Division Virginia Department of Environmental Quality P.O. Box 1105 Richmond, VA 23218 Mr. Justin Williams, Director Division of Land Protection and Revitalization Virginia Department of Environmental Quality P.O. Box 1105 Richmond, VA 23218 Mr. James Golden, Regional Director Virginia Department of Environmental Quality Piedmont Regional Office 4949-A Cox Road Glen Allen, VA 23060 Mr. Craig R. Nicol, Regional Director Virginia Department of Environmental Quality Tidewater Regional Office 5636 Southern Blvd Virginia Beach, VA 23462 Ms. Jewel Bronaugh, Commissioner Virginia Department of Agriculture & Consumer Services 102 Governor Street Richmond, Virginia 23219 Mr. Jason Bulluck, Director Virginia Department of Conservation & Recreation Virginia Natural Heritage Program 600 East Main Street, 24th Floor Richmond, VA 23219 Mr. Robert W. Duncan, Director Virginia Department of Game and Inland Fisheries P.O. Box 90778 Henrico, VA 23228 Serial Nos.19-468 Docket Nos 50-280/281 Change Notice 6 Page 5 of 7

Mr. Allen Knapp, Director Virginia Department of Health Office of Environmental Health Services 109 Governor St, 5th Floor Richmond, VA 23129 Ms. Julie Lagan, Director Virginia Department of Historic Resources State Historic Preservation Office 2801 Kensington Ave Richmond, VA 23221 Mr. Steven G. Bowman, Commissioner Virginia Marine Resources Commission 2600 Washington Ave Newport News, VA 23607 Dr. Mary Fabrizio, Professor Virginia Institute of Manne Science School of Marine Science 7509 Roper Rd, Nunnally Hall 135 Gloucester Point, VA 23062 Ms. Angel Deem, Director Virginia Department of Transportation Environmental Division 1401 East Broad St Richmond, VA 23219 Mr. Stephen Moret, President Virginia Economic Development Partnership 901 East Byrd St Richmond, VA 23219 Mr. William F. Stephens, Director Virginia State Corporation Commission Division of Public Utility Regulation 1300 East Main St, 4th Fl, Tyler Bldg Richmond, VA 23219 Serial Nos.19-468 Docket Nos. 50-280/281 Change Notice 6 Page 6 of 7

Mr. Jeff Caldwell, Director Virginia Department of Emergency Management 10501 Trade Rd Richmond, VA 23236 Mr. Bruce Sterling, Chief Regional Coordinator Virginia Department of Emergency Management 7511 Burbage Dr.

Suffolk, VA 23435 Mr. Jonathan Lynn, Administrator Surry County 45 School Street Surry, VA 23883 Serial Nos.19-468 Docket Nos. 50-280/281 Change Notice 6 Page 7 of 7 Serial Nos.: 19-468 Docket Nos.: 50-280/281 RESPONSE TO DRAFT RAls - CHANGE NOTICE 6 Virginia Electric and Power Company (Dominion Energy Virginia or Dominion)

Surry Power Station Units 1 and 2

Comment#

NRC Comment Based on discussions wrth NRG environmental reviewers, the water table can vary by feet at Surry due to tidal fluctuations 2

and seasonal changes. It is unclear why the selection of exploratory hole locations does not take into account the potential for high levels of groundwater.

On its October 31, 2019 letter, the applicant committed to:

"Prior to excavation, it shall be confirmed that the south side of the turbine building is not covered with a bitumastic coating below grade."

Since the surrogate structure may be coated, it is unclear why additional corrective actions would not also consider more frequent inspections of the concrete CW piping.

The commitment should clearly reflect that the applicant intends to confirm that the below grade concrete surface of the turbine building is bare concrete absent of any sort of material 5

covering its surface and is equivalent to the CW piping concrete surface.

Neither the staff nor applicant know whether the below grade concrete of the turbine building has any sort of water-resistant coating, membrane, or other material covering its surface and therefore rendering the concrete to not be equally exposed to the ground water environment that the CW piping bare concrete is.

The staff notes that if there's any type of material covering the concrete surface of the turbine building then the applicant can no longer claim that the turbine building concrete/environment is equivalent to that of the CW piping and therefore should Serial Nos.: 19-468 Docket Nos.: 50-280/281 Dominion Response Dominion will include consideration for seasonal variations to account for high levels of ground water as shown on the attached markup of SLRA page B-157, from Section 82.1.21, Selective Leaching.

Dominion has revised the indicated commitment to reflect that the south side of the Turbine Building be confirmed to be bare concrete below grade prior to excavation.

Bare concrete below grade will confirm that there is no material of any type covering the concrete surface of the Turbine Building; therefore, the Turbine Building concrete/environment is equivalent to that of the CW piping.

Markups for SLRA Table A4.0-1, Item 11 and excerpts from SLRA Sections 82.1.21 and 82.1.27 that reflect the above change are attached.

proceed Ol)IY to inspect the CW piping instead of a surrogate turbine building structure.

SLRA Section 82.1.27, Enhancement No. 8 states in part u[i]f a coating is identified, then: Excavation of one 96" CW pipe will be performed to inspect a surface area of 50 square-ft 6

located below groundwater level."

Clarification only: Is the intent to use GALL-SLR Report AMP XI.M41 acceptance criteria and corrective actions if the surrogate structure is coated and the concrete CW pipe is inspected?

Serial Nos.: 19-468 Docket Nos.: 50-280/281 If the Turbine Building is determined to not be bare, GALL-SLR Report AMP XI. M41 acceptance criteria and corrective actions will be used for the 96" CW pipe that is excavated for inspection.

SLRA MARK-UPS - CHANGE NOTICE 6 Virginia Electric and Power Company (Dominion Energy Virginia or Dominion)

Surry Power Station Units 1 and 2 Serial Nos.: 19-468 Docket Nos.: 50-280/281

Table A4.0-1 Subsequent License Renewal Commitments Program Commitment AMP Implementation

8. e[Q@!:!1.11:e(sl ~ill be gellelocie!:l to cierform a one-time iasciei:.tioa (oae exi:;avatioa) for elli!:leo@ of i:.oai:;rete agiag (below gracie} assQi:;iateci !tlith eiU'leF O'le YAil ~ eF YAit ~ HigR l::eYel IAtake ~F1:1el1:1Fes, eF the sQuth sjcie Qf the Turbiae Builciiag.

• witb the fQIIQwjng regyirementli: (Revise!:! - Change NQti@ 5) (Bellisei;l - Chaage ~Qti@ 6)

Program will be

a. erior to exQs!llation, it shall be i:;onfianed tbat tbe soutb sicie of tbe Iui:biae 6uildiog is Aet eeYeFeEI,...,itR a 13it1:1masue implemented and eeat+A§bare i:;oni:;rete below grai;le inspections begin

b. 11.a eeatiAg is Aet iEleAtifieElbace i:.oai:;rete is i:.oafianed then*

1 O years before the

• eF tl=le FiFe P1:1mJ:1 He1:1seA miaimum of 50 ~ concrete syrfa@ area belQw tl=le frest leYel g[Qyndwater level will be subsequent period of extended iospeQted bl£ tbe ooe-time iospeQtiQD, operation.

• IlliUIFeeeEl1:1Fe will Feei1:1iF0 tRat, as a s1:1FFegate leeaUeA, tl=le ellalyatiQD Qf tbe QOe-tjme iaspeQtiQD results ~

Inspections that are iai:;lyge evs1lys1tiQD Qf th!;! a!:.@12ta!;!ilitl£ Qf the eigbt ios1i:.@ssible 92;:ini:;b cw ciicies loQs!ted betweea tbe High L.ell!;!l lats1ke to be completed prior to the Buried and strus.tures aaci the IYcbiae Buildiag usiag the guiciaai:.e ia ACI 349.~

subsequent period Underground

• If o!;!seeyed age-relateg degcadation ex@e!:ls ACI 349.3B ]er-1 i:;riteda tben the area i:;ontaioiag the degradation will of extended 27 82.1.27 Piping and Tanks b!i! !i!llaluated fQr ai:.@ptatliiilll l:!ll a resgQasitll!i! Cillil i;;ngia1;1ec ysiag tbe CQcrni:.lill!i! Ai:;tiQD eCQgcam Ibe el£aluatiQa lihall operation are program iaQlude the ai:;i:;eptabilitl£ of tbe eight ioai:.@ssible 96-ini:;b cw pipes loQs!te!:l between the High Level latake StruQtures completed 6 months prior to the and tbe Tyrtliae Byilding Yliiag the gyjdan@ in ACI 349 38 subsequent period

• If observed age-relate!:! degradatiQD ex@egs ACI 349.3R Tier-1 i:;riteria, a s!,!bsequent inspeQtion will !;!e performed of extended witbia ten l£ears tQ determine if th1;1 previQ!.!lilll Qbservei;l degradatiQn remaias witbio the parameters evaluated d!,!riag operation or no later the orevioys inlipec;tion. If the i;legradation d!.!ring the subsequent inspeQtiQO mQre than margins1lll£ ex@eds the than the last refueling outage eval!,!ated parameters frQm tbe pr!;!ViQus insciei:;tion th!;!n ~itihin five ll!i!acs an !;!xi:;avation of on!;! 96-ini:;h cw Pil:l!i! will be prior to the perfQCmed to iaspei:;t a suctai:.e s1rea Qf 50 ttZ. IQQated below g[Qundwater level subsequent period C. 11.a eeatiA§ is iEleAtifieElbare QQni:;rete is not QQOficmed tbea-of extended

• Exi:.allaliQO Qf Qae 96-ioi:.b Q':lJ.. pjpe !tiill be pecfQ!Jiled to ios12eQt a surfai:.e area Qf 50 ~ 12!:.s!ted belQ!ti g[Qund!(Yater operation.

Je.llel.

Surry Power Station, Units 1 and 2 Application for Subsequent License Renewal Appendix A - UFSAR Supplement PageA-92 Change Notice 6 Serial No.: 19-468

Excerpt from B2.1.21, Selective Leaching Change Notice 6 Surry Power Station, Units 1 and 2 Application for Subsequent License Renewal Appendix B - Aging Management Programs equalize total run times among the diesels, so as to equalize wear and aging. Operating experience for each unit demonstrates no significant difference in aging effects of systems in the scope of this program between the two units.

Inspections will be performed by personnel qualified in accordance with procedures and programs to perform the specified task. Inspections within the scope of the ASME Code will follow procedures consistent with the ASME Code. Non-ASME Code inspection procedures will include requirements for items such as lighting, distance, offset, and surface conditions.

Inspection results will be evaluated against acceptance criteria to confirm that the sampling bases (e.g., selection, size, frequency) will maintain the components' intended functions throughout the subsequent period of extended operation based on the projected rate and extent of degradation.

The acceptance criteria are:

• For copper-based alloys, no noticeable change in color from the normal yellow color to the reddish copper color or green copper oxide,

• For gray cast iron and ductile iron, the absence of a surface layer that can be easily removed by chipping or scraping or identified in the destructive examinations,

• The presence of no more than a superficial layer of dealloying, as determined by removal of the dealloyed material by mechanical removal, and

• The components meet system design requirements such as minimum wall thickness, when extended to the end of the subsequent period of extended operation.

When the acceptance criteria are not met such that it is determined that the affected component should be replaced prior to the end of the subsequent period of extended operation, additional inspections will be performed. If subsequent inspections do not meet acceptance criteria, an extent of condition and extent of cause analysis will be conducted to determine the further extent of inspections. Extent of condition and extent of cause analysis will include evaluation of difficult-to-access surfaces if unacceptable inspection findings occur within the same material and environment population. The timing of the additional inspections is based on the severity of the degradation identified and is commensurate with the potential for loss of intended function.

The Selective Leaching program (82.1.21) will be augmented to include a requirement to dig exploratory holes to confirm the presence of groundwater around the buried fire water main loop piping, excavate/examine to identify selective leaching, project any identified degradation, and determine necessary future inspections based on the following:

Exploratory Holes for Groundwater A minimum of 25 exploratory holes will be drilled prior to the subsequent period of extended operation (SPEO) and during each 1 O year inspection interval in the SPEO to identify suspected system leakage or elevated groundwater. The selection of exploratory hole PageB-156 Serial No.: 19-468

Excerpt from B2.1.21, Selective Leaching Change Notice 6 Surry Power Station, Units 1 and 2 Application for Subsequent License Renewal Appendix B - Aging Management Programs sample locations will take into account recent soil sample results, piping most susceptible to aging based on time-in-service, and the severity of piping operating conditions (including considerations for seasonal variations) (Revised - Change Notice 6).

Exploratory holes will be drilled in areas of suspected system leakage or elevated groundwater.

Exploratory holes will be drilled to the maximum depth of the fire protection loop piping.

When water is detected, as a minimum it will be analyzed for pH, chlorides and sulfates.

Fire protection loop piping will be excavated and inspected at each hole where groundwater has been confirmed and corrective actions implemented based on the inspection results.

Each excavation will also include a soil sample, in accordance with the Buried and Underground Piping and Tanks program (82.1.27) that will be analyzed and the results evaluated with the excavation inspection results.

Corrective Actions for Presence of Groundwater If water in an exploratory hole is identified to be a result of fire protection system leakage or other plant system leakage and not due to elevated groundwater, then corrective actions consistent with the Selective Leaching program (82.1.21) will be initiated.

If water in an exploratory hole is identified to be a result of elevated groundwater, then five additional exploratory holes will be drilled to confirm the extent of the elevated groundwater area. If the additional exploratory holes discover groundwater, an extent of condition analysis will be conducted to determine the extent of additional drillings required. Fire protection loop piping at the additional exploratory holes with groundwater will be excavated for examination.

If no additional areas of elevated groundwater are identified beyond the area initially confirmed to have elevated groundwater during July 2019 or during the first SPEO 10-year exploratory hole sample location inspections, an extent of condition analysis will be conducted to determine the extent of excavations required for the first and second SPEO inspection intervals. The extent of condition analysis will take into account corrective actions (e.g., piping replacement) and inspection projections conducted for the initial area of confirmed elevated groundwater (which occurred in July 2019.)

Sample Expansion (Selective Leaching due to Elevated Groundwater)

For each excavation, a minimum of ten feet of buried fire protection main loop piping will be excavated, cleaned using aggressive cleaning techniques sufficient to remove de-alloyed material and visually examined for evidence of selective leaching.

A minimum of five destructive exams will be performed in separate one foot sample sections of fire protection pipe that exhibit signs of selective leaching.

Acceptance criteria will be consistent with the Selective Leaching program (82.1.21).

An extent of condition analysis will be conducted to determine extent of further inspections.

PageB-157 Serial No.: 19-468

Excerpt from B2.1.27 Buried and Underground Piping and Tanks Change Notice 6

2.

(Completed Change Notice 2)

Surry Power Station, Units 1 and 2 Application for Subsequent License Renewal Appendix B - Aging Management Programs

3.

Procedures will be revised to obtain pipe-to-soil potential measurements for piping in the scope of SLR during the next soil survey within 1 O years prior to entering the subsequent period of operation. (Added - Set 1 RAls)

Preventive Actions (Element 2) and Detection of Aging Effects (Element 4)

4.

Procedures will be revised to require uncoated buried stainless steel tubing segments in the fuel oil system be inspected prior to the subsequent period of extended operation. After inspection, each uncoated stainless steel segment will be coated consistent with Table 1 of NACE SP0169-2007, "Control of External Corrosion on Underground or Submerged Metallic Piping Systems" (Added - Set 1 RAls) (Revised - Set 3 RAls)

5.

A cathodic protection system will be installed for protection of the 24-inch service water piping at the Low Level Intake Structure five years before entering the subsequent period of operation. (Added - Set 3 RAls)

6.

A cathodic protection system will be installed for protection of each unit's buried carbon steel condensate system and auxiliary feedwater system piping from the emergency condensate storage tank and the emergency condensate makeup tank to the service building five years before entering the subsequent period of operation. (Added - Change Notice 4)

Parameters Monitored/Inspected (Element 3)

7.

Procedures will be enhanced to perform two soil corrosivity samples: one adjacent to the Unit 1 circulating water inlet piping and another adjacent to the Unit 2 circulating water inlet piping.

Sampling will be performed on a ten year interval. Data collected at each location will include:

soil resistivity, soil consortia (bacteria), pH, moisture, chlorides, sulfates, and redox potential.

In addition to evaluating each individual parameter, corrosivity of carbon steel reinforcement and concrete degradation in high sulfate, high chlorides and acidic environments will be evaluated. (Added - Change Notice 5)

Detection of Aging Effects (Element 4)

8.

Procedure(s) will be developed to perform a one-time inspection (one excavation) for evidence of concrete aging (below grade) associated with the south side of the Turbine Building with the following requirements: (Revised - Change Notice 5) {Revised - Change Notice 6)

a. Prior to excavation, it shall be confirmed that the south side of the Turbine Building is Bet oovered with a bitumastio ooatingbare concrete below grade.

PageB-191 Serial No.: 19-468

Excerpt from B2.1.27 Buried and Underground Piping and Tanks Change Notice 6 Surry Power Station, Units 1 and 2 Application for Subsequent License Renewal Appendix B - Aging Management Programs

b. If a seating is not identifiedbare concrete is confirmed, then:

• A minimum of 50 ft2 concrete surface area below groundwater level will be inspected by the one-time inspection.

• The evaluation of the one-time inspection results shall include evaluation of the acceptability of the eight inaccessible 96-inch CW pipes located between the High Level Intake Structures and the Turbine Building using the guidance in ACI 349.3R.

• If observed age-related degradation exceeds ACI 349.3R Tier-1 criteria, then the area containing the degradation will be evaluated for acceptability by a responsible Civil Engineer using the Corrective Action Program. The evaluation shall include the acceptability of the eight inaccessible 96-inch CW pipes located between the High Level Intake Structures and the Turbine Building using the guidance in ACI 349.3R.

• If observed age-related degradation exceeds ACI 349.3R Tier-1 criteria, a subsequent inspection will be performed within ten years to determine if the previously observed degradation remains within the parameters evaluated during the previous inspection. If the degradation during the subsequent inspection more than marginally exceeds the evaluated parameters from the previous inspection, then within 5 years an excavation of one 96" CW pipe will be performed to inspect a surface area of 50 ft2 located below groundwater level. (Added - Change Notice 4)

c. If a coating is identifiedbare concrete is not confirmed, then:

• Excavation of one 96" CW pipe will be performed to inspect a surface area of 50 ft2 located below groundwater level.

Acceptance Criteria (Element 6)

9.

Procedures will be revised to specify that cathodic protection surveys use the -850mV polarized potential, instant off criterion specified in NACE SP0169-2007 for steel piping acceptance criteria unless a suitable alternative polarization criteria can be demonstrated.

Alternatives will include the -100mV polarization criteria, -750mV criterion (soil resistivity is less than 100,000 ohm-cm), -650mV criterion (soil resistivity is greater than 100,000 ohm-cm),

or verification of less than 1 mpy loss of material rate.

The external loss of material rate is verified:

• Every year when verifying the effectiveness of the cathodic protection system by measuring the loss of material rate.

• Every 2 years when using the 100 mV minimum polarization.

• Every 5 years when using the -750 or -650 criteria associated with higher resistivity soils.

The soil resistivity is verified every 5 years.

PageB-1 92 Serial No.: 19-468