1、Designation: G158 98 (Reapproved 2016)Standard Guide forThree Methods of Assessing Buried Steel Tanks1This standard is issued under the fixed designation G158; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThe purpose of this guide is to provide three methods of inspecting and assessing buried steeltank(s) for corrosion damage and de
3、termining the suitability of these tanks prior to application ofcathodic protection.1. Scope1.1 This guide covers procedures to be implemented prior tothe application of cathodic protection for evaluating the suit-ability of a tank for upgrading by cathodic protection alone.1.2 Three procedures are
4、described and identified as Meth-ods A, B, and C.1.2.1 Method ANoninvasive with primary emphasis onstatistical and electrochemical analysis of external site envi-ronment corrosion data.1.2.2 Method BInvasive ultrasonic thickness testing withexternal corrosion evaluation.1.2.3 Method CInvasive perman
5、ently recorded visual in-spection and evaluation including external corrosion assess-ment.1.3 This guide presents the methodology and the proceduresutilizing site and tank specific data for determining a tankscondition and the suitability for such tanks to be upgraded withcathodic protection.1.4 The
6、 tanks condition shall be assessed using Method A,B, or C. Prior to assessing the tank, a preliminary site surveyshall be performed pursuant to Section 8 and the tank shall betightness tested pursuant to 5.2 to establish that the tank is notleaking.1.5 While this guide provides minimum procedures fo
7、rassessing a tanks condition, this guide does not provideminimum installation procedures or requirements for upgradesof the tank by cathodic protection.1.6 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units tha
8、t are provided for information onlyand are not considered standard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the ap
9、plica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 The most recent version of the following documentsshould be consulted as references by those using this guide:2.2 ASTM Standards:2D2216 Test Methods for Laboratory Determination of Water(Moisture) Content of Soil and Rock
10、 by MassE114 Practice for Ultrasonic Pulse-Echo Straight-BeamContact TestingE797 Practice for Measuring Thickness by Manual Ultra-sonic Pulse-Echo Contact MethodE1323 Guide for Evaluating Laboratory Measurement Prac-tices and the Statistical Analysis of the Resulting DataE1526 Practice for Evaluatin
11、g the Performance of ReleaseDetection Systems for Underground Storage Tank Sys-tems (Withdrawn 2002)3G51 Test Method for Measuring pH of Soil for Use inCorrosion TestingG57 Test Method for Field Measurement of Soil ResistivityUsing the Wenner Four-Electrode Method1This guide is under the jurisdictio
12、n of ASTM Committee G01 on Corrosion ofMetals and is the direct responsibility of Subcommittee G01.10 on Corrosion inSoils.Current edition approved May 1, 2016. Published May 2016. Originallyapproved in 1998. Last previous edition approved in 2010 as G158 98 (2010).DOI: 10.1520/G0158-98R16.2For refe
13、renced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced o
14、nwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.3 ASNT Standard:4ASNT SNT-TC-1A Personnel Qualification and Certifica-tion in Nondestructive Testing2.4 NACE International Standards:5RP-0169 Standard Recommended Practic
15、e-Control on Ex-ternal Corrosion on Underground or Submerged MetallicPiping SystemsRP-0187 Standard Recommended Practice-Design Consid-erations for Corrosion Control of Reinforcing Steel inConcreteRP-0285 Standard Recommended Practice-Corrosion Con-trol of Underground Storage Tank Systems by Cathodi
16、cProtection2.5 Environmental Protection Agency Methods:6EPA SW 846 Test Methods for Evaluating Solid WasteEPA 371.1 Measurement of Sulfate Reducing Bacteria2.6 National Fire Protection Association (NFPA)7NFPA 329 Recommended Practice for Handling Under-ground Releases of Flammable and Combustible Li
17、quids2.7 Underwriters Laboratories Inc.8UL 58 Steel Underground Tanks for Flammable and Com-bustible Liquids3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 buriedto be placed in the ground and covered withearth.3.1.2 cathodic protectionan applied technique to preventfurther co
18、rrosion of a metal surface by making that surface thecathode of an electrochemical cell. For example, a tank systemcan be cathodically protected through the application of eithergalvanic anodes or impressed current.3.1.3 corrosion specialist/cathodic protection specialistacompetent person who by rea
19、son of knowledge of the physicalsciences and the principles of engineering and mathematics,acquired by education and related practical experience, isqualified to engage in the practice of corrosion control onburied or submerged metallic piping systems and metallictanks. Such persons shall be registe
20、red professional engineersor persons recognized as corrosion specialists or cathodicprotection specialists by NACE, if their professional activitiesinclude suitable experiences in external corrosion control onburied or submerged metallic piping and tanks.3.1.4 corrosion techniciana person possessing
21、 basicknowledge of corrosion and corrosion control, who is capableof performing routine, well defined work under the supervisionof the corrosion specialist/cathodic protection specialist.3.1.5 invasive procedurea method of determining thecorrosion status of a tank by assessing the tank from the insi
22、deas part of the upgrade procedure. Further, for the purposes ofthis guide, it does not require manned entry into the tank. (Seenon-invasive.)3.1.6 limitationsThe user of this guide is encouraged toreview any available third party verification information pro-vided as part of the vendor selection pr
23、ocess.3.1.7 noninvasive procedurea method of determining thecorrosion status of a tank from the characteristics of itssurroundings with minimal entry into the tank. Further, for thepurposes of this guide, it does not require manned entry intothe tank. (See invasive.)3.1.8 pHthe numerical value of th
24、e negative logarithm ofthe hydrogen ion concentration in moles per litre in anelectrolyte.3.1.9 redox potentialpotential of platinized platinum elec-trode in a redox environment (reversible system). The value ofredox potential depends on whether the system is in theoxidized, partially oxidized, part
25、ially reduced, or reduced state.3.1.10 tank tightness testa method capable of detecting a0.1 gal/h leak rate, while accounting for any applicable effectsof thermal expansion or contraction of the product, of vaporpockets, of tank deformation, of evaporation or condensation,and of the location of the
26、 water table. The method must becapable of detecting a 0.1 gal/h leak rate with a probability ofdetection of at least 0.95 and a probability of false alarm of atmost 0.05 or in accordance with NFPA 329.3.1.11 unconditional probability of corrosion failuretheprobability of corrosion failure which inc
27、ludes a determinationof whether localized, pitting, or general corrosion is occurring.3.1.12 underground storage tank (UST)any one or com-bination of tanks (including connected underground piping),the volume of which is 10 % or more beneath the surface of theground.3.1.13 upgradethe addition to or r
28、etrofit of UST systemsusing approaches including, but not limited to, cathodic pro-tection to improve the ability of a UST system to prevent arelease.3.1.14 USTsee underground storage tank (see 3.1.12).3.1.15 vendor provided informationThe user is referred toAnnex A1 for a specific form and format o
29、f information whichmust be provided by a vendor. This information consists ofhistoric performance data on a method and is mandated as partof the guide.4. Significance and Use4.1 This guide provides three methods for determining thesuitability of a buried steel tank to be upgraded with cathodicprotec
30、tion.4.2 This guide may be used to assess any UST, includingnon-regulated USTs.4.3 This guide provides three alternative methods but doesnot recommend any specific method or application. Theresponsibility for selection of a method rests with the user.4Available from TheAmerican Society for Nondestru
31、ctive Testing (ASNT), P.O.Box 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518.5Available from National Association of Corrosion Engineers (NACE), 1440South Creek Dr., Houston, TX 77084-4906.6Available from US Environmental Protection Agency, Office of UndergroundStorage Tanks, 401 “M” St. SW, Was
32、hington, DC 20460.7Available from Underwriters Laboratories (UL), Corporate Progress, 333Pfingsten Rd., Northbrook, IL 60062.8Available from National Fire Protection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02269-9101.G158 98 (2016)24.4 This guide has specific requirements for vendor pro-v
33、ided information which should be requested and reviewed bythe user.5. Permits, Plans and Tank Leak Testing5.1 Prior to engaging in any activities relating to thealteration, repair, or upgrade of any UST system, consult allnecessary authorities to obtain any required permits.5.2 Tank Leak Testing:5.2
34、.1 To establish that tanks are not leaking prior toassessment, they shall be assessed by a leak detection system.This leak detection assessment alone is not sufficient todetermine that a tank is suitable for upgrading with cathodicprotection under this guide.5.2.2 A tightness test or another release
35、 detection system inaccordance with NFPA329 shall be used.Any release detectionmust be capable of detecting a leak from any portion of thetank that routinely contains product, and be independentlyevaluated and certified in accordance with Practice E1526 orthe equivalent. Leak detection results shall
36、 be provided to thecorrosion specialist/cathodic protection specialist.5.2.3 This testing shall be accomplished within six monthsprior to performing any of the assessment procedures.6. Required Approvals and Certifications6.1 The corrosion assessment work carried out under thisguide shall be perform
37、ed under the responsible direction of acorrosion specialist/cathodic protection specialist as defined in3.1.3.6.2 The corrosion specialist/cathodic protection specialistshall certify to the tank owner or operator that the personnelperforming the assessment work on the tank are knowledgeableof all th
38、e applicable procedures in this guide.6.3 The corrosion specialist/cathodic protection specialistshall certify to the tank owner or operator that all work wasperformed in strict accordance with this guide.7. General Safety Requirements7.1 All personnel shall comply with applicable federal,state, and
39、 local health and safety codes and regulations.8. Preliminary Site Survey8.1 A corrosion technician, under the responsible directionof the corrosion specialist/cathodic protection specialist, shallobtain tank site specific information as appropriate to themethod of assessment to be used.8.1.1 Facili
40、ty Information:8.1.1.1 Address or location, and8.1.1.2 Name and telephone number of owner and operatorcontact personnel.8.1.2 Tank and Piping Details:8.1.2.1 Number and capacity,8.1.2.2 Location and dimensions,8.1.2.3 Age,8.1.2.4 Material of construction,8.1.2.5 Electrical isolation,8.1.2.6 Type of
41、product stored,8.1.2.7 Names of site contact personnel,8.1.2.8 Backfill material,8.1.2.9 Coatings and linings,8.1.2.10 Leak history,8.1.2.11 Repair history,8.1.2.12 Site plans,8.1.2.13 Installation specifications,8.1.2.14 Tank excavation liners, and8.1.2.15 As-built drawings.8.1.3 Information Not in
42、 the Immediate Vicinity of theTanksThe presence of the following items, that are externalto the tank area, shall be investigated and included as appro-priate to the method of assessment of the suitability of tanks forupgrading with cathodic protection:8.1.3.1 Stray dc current sources,8.1.3.2 Existin
43、g cathodic protection systems,8.1.3.3 Steel product and vent piping and fittings, and8.1.3.4 Adjacent subsurface metallic/steel-reinforced con-crete structures.8.2 Preliminary EvaluationPrior to assessing the tank, apreliminary site survey must be performed pursuant to Section8 and a tightness test
44、must be performed pursuant to 5.2 toestablish that the tank is not leaking.9. Method ANoninvasive with Primary Emphasis onStatistical and Electrochemical Analysis of ExternalSite Environment Corrosion Data (1, 2)9.1 Field and Laboratory TestingNoninvasive with Pri-mary Emphasis on Statistical and El
45、ectrochemical Analysis ofExternal Site Environment Corrosion Data.9.1.1 Tests shall be conducted by, or as directed by acorrosion specialist/cathodic protection specialist.9.1.2 Field Testing ProceduresTests to be performed shallinclude, but are not limited to, the following:9.1.2.1 Stray CurrentsPe
46、rform tests to detect the presenceof stray currents at each tank site. This test shall consist ofmeasuring structure-to-soil potentials at right angles at aminimum of two locations within the tank facilities andobserving the measurements for not less than2hatatimewhen such influences are most likely
47、 to occur. The monitorshall consist of a field data acquisition unit, with a minimum of10-M input impedance, used in conjunction with a stablereference cell(s) placed in contact with the soil in the vicinityof the tank. The instrument shall measure and store structure-to-electrolyte potential (volta
48、ge) data at least every 5 s through-out the entire duration of field investigation at the site or for 2h, whichever is greater. If variations of 650 mV or greater aremeasured during the test period, make 24-h recording measure-ments to confirm stray current effects.9.1.2.2 Tank Information:(a) Locat
49、e all tanks and confirm materials of construction,age, capacity, and dimensions. Produce detailed site sketchesdescribing the layout of the UST system and above gradepertinent details for each site.(b) Determine the presence and extent of internal corrosionimmediately below the fill riser. If the depth of corrosionG158 98 (2016)3penetration in the tank shell exceeds 50 % of the tank wallthickness, the UST shall be declared to have failed the test andthe procedure.(c) Determine if the tanks and piping are electricallycontinuous.9.1.2.3 Bore Hole Tests:(a
