ASTM G158-98(2004)
(Guide)Standard Guide for Three Methods of Assessing Buried Steel Tanks
Standard Guide for Three Methods of Assessing Buried Steel Tanks
SIGNIFICANCE AND USE
This guide provides three methods for determining the suitability of a buried steel tank to be upgraded with cathodic protection.
This guide may be used to assess any UST, including non-regulated USTs.
This guide provides three alternative methods but does not recommend any specific method or application. The responsibility for selection of a method rests with the user.
This guide has specific requirements for vendor provided information which should be requested and reviewed by the user.
SCOPE
1.1 This guide covers procedures to be implemented prior to the application of cathodic protection for evaluating the suitability of a tank for upgrading by cathodic protection alone.
1.2 Three procedures are described and identified as Methods A, B, and C.
1.2.1 Method ANoninvasive with primary emphasis on statistical and electrochemical analysis of external site environment corrosion data.
1.2.2 Method BInvasive ultrasonic thickness testing with external corrosion evaluation.
1.2.3 Method CInvasive permanently recorded visual inspection and evaluation including external corrosion assessment.
1.3 This guide presents the methodology and the procedures utilizing site and tank specific data for determining a tank's condition and the suitability for such tanks to be upgraded with cathodic protection.
1.4 The tank's condition shall be assessed using Method A, B, or C. Prior to assessing the tank, a preliminary site survey shall be performed pursuant to Section and the tank shall be tightness tested pursuant to to establish that the tank is not leaking.
1.5 While this guide provides minimum procedures for assessing a tank's condition, this guide does not provide minimum installation procedures or requirements for upgrades of the tank by cathodic protection.
1.6 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are provided for information only.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation: G158 – 98 (Reapproved 2004)
Standard Guide for
Three Methods of Assessing Buried Steel Tanks
This standard is issued under the fixed designation G158; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The purpose of this guide is to provide three methods of inspecting and assessing buried steel
tank(s) for corrosion damage and determining the suitability of these tanks prior to application of
cathodic protection.
1. Scope responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
1.1 Thisguidecoversprocedurestobeimplementedpriorto
bility of regulatory limitations prior to use.
the application of cathodic protection for evaluating the suit-
ability of a tank for upgrading by cathodic protection alone.
2. Referenced Documents
1.2 Three procedures are described and identified as Meth-
2.1 The most recent version of the following documents
ods A, B, and C.
should be consulted as references by those using this guide:
1.2.1 Method A—Noninvasive with primary emphasis on
2.2 ASTM Standards:
statistical and electrochemical analysis of external site envi-
D2216 Test Methods for Laboratory Determination of Wa-
ronment corrosion data.
ter (Moisture) Content of Soil and Rock by Mass
1.2.2 Method B—Invasive ultrasonic thickness testing with
E114 Practice for Ultrasonic Pulse-Echo Straight-Beam Ex-
external corrosion evaluation.
amination by the Contact Method
1.2.3 Method C—Invasive permanently recorded visual in-
E797 Practice for Measuring Thickness by Manual Ultra-
spection and evaluation including external corrosion assess-
sonic Pulse-Echo Contact Method
ment.
E1323 GuideforEvaluatingLaboratoryMeasurementPrac-
1.3 This guide presents the methodology and the procedures
tices and the Statistical Analysis of the Resulting Data
utilizing site and tank specific data for determining a tank’s
E1526 Practice for Evaluating the Performance of Release
condition and the suitability for such tanks to be upgraded with
Detection Systems for Underground Storage Tank Sys-
cathodic protection.
tems
1.4 The tank’s condition shall be assessed using MethodA,
G51 Test Method for Measuring pH of Soil for Use in
B, or C. Prior to assessing the tank, a preliminary site survey
Corrosion Testing
shall be performed pursuant to Section 8 and the tank shall be
G57 Test Method for Field Measurement of Soil Resistivity
tightness tested pursuant to 5.2 to establish that the tank is not
Using the Wenner Four-Electrode Method
leaking.
2.3 American Society for Nondestructive Testing Stan-
1.5 While this guide provides minimum procedures for
dard:
assessing a tank’s condition, this guide does not provide
ASNT SNT-TC-1A Personnel Qualification and Certifica-
minimum installation procedures or requirements for upgrades
tion in Nondestructive Testing
of the tank by cathodic protection.
2.4 NACE International Standards:
1.6 The values stated in inch-pound units are to be regarded
as the standard. The SI units given in parentheses are provided
for information only.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1.7 This standard does not purport to address all of the
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
safety concerns, if any, associated with its use. It is the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Withdrawn.
1 4
This guide is under the jurisdiction ofASTM Committee G01 on Corrosion of Withdrawn. The last approved version of this historical standard is referenced
Metals and is the direct responsibility of Subcommittee G01.10 on Corrosion in on www.astm.org.
Soils. Available fromTheAmerican Society for NondestructiveTesting (ASNT), P.O.
Current edition approved May 1, 2004. Published May 2004. Originally Box 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518.
approved in 1998. Last previous edition approved in 1998 as G158 – 98. DOI: Available from National Association of Corrosion Engineers (NACE), 1440
10.1520/G0158-98R04. South Creek Dr., Houston, TX 77084-4906.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
G158 – 98 (2004)
RP-0169 Standard Recommended Practice-Control on Ex- purposes of this guide, it does not require manned entry into
ternal Corrosion on Underground or Submerged Metallic the tank. (See invasive.)
Piping Systems 3.1.7 pH—the numerical value of the negative logarithm of
RP-0187 Standard Recommended Practice-Design Consid- the hydrogen ion concentration in moles per litre in an
erations for Corrosion Control of Reinforcing Steel in electrolyte.
Concrete 3.1.8 tank tightness test—a method capable of detecting a
RP-0285 Standard Recommended Practice-Corrosion Con- 0.1 gal/h leak rate, while accounting for any applicable effects
trol of Underground Storage Tank Systems by Cathodic of thermal expansion or contraction of the product, of vapor
Protection pockets, of tank deformation, of evaporation or condensation,
2.5 Environmental Protection Agency Methods: and of the location of the water table. The method must be
EPA SW 846 Test Methods for Evaluating Solid Waste capable of detecting a 0.1 gal/h leak rate with a probability of
EPA 371.1 Measurement of Sulfate Reducing Bacteria detection of at least 0.95 and a probability of false alarm of at
2.6 National Fire Protection Association (NFPA) most 0.05 or in accordance with NFPA 329.
NFPA 329 Recommended Practice for Handling Under- 3.1.9 underground storage tank (UST)—any one or combi-
nation of tanks (including connected underground piping), the
ground Releases of Flammable and Combustible Liquids
volume of which is 10 % or more beneath the surface of the
2.7 Underwriters Laboratories Inc.
ground.
UL 58 Steel Underground Tanks for Flammable and Com-
3.1.10 upgrade—the addition to or retrofit of UST systems
bustible Liquids
using approaches including, but not limited to, cathodic pro-
tection to improve the ability of a UST system to prevent a
3. Terminology
release.
3.1 Definitions of Terms Specific to This Standard:
3.1.11 unconditional probability of corrosion failure—the
3.1.1 buried—to be placed in the ground and covered with
probability of corrosion failure which includes a determination
earth.
of whether localized, pitting, or general corrosion is occurring.
3.1.2 cathodic protection—an applied technique to prevent
3.1.12 UST—see underground storage tank (see 3.1.9).
further corrosion of a metal surface by making that surface the
3.1.13 redox potential—potential of platinized platinum
cathode of an electrochemical cell. For example, a tank system
electrode in a redox environment (reversible system). The
can be cathodically protected through the application of either
value of redox potential depends on whether the system is in
galvanic anodes or impressed current.
the oxidized, partially oxidized, partially reduced, or reduced
3.1.3 corrosion specialist/cathodic protection specialist—a
state.
competent person who by reason of knowledge of the physical
3.2 limitations—The user of this guide is encouraged to
sciences and the principles of engineering and mathematics,
review any available third party verification information pro-
acquired by education and related practical experience, is
vided as part of the vendor selection process.
qualified to engage in the practice of corrosion control on
3.3 vendor provided information—The user is referred to
buried or submerged metallic piping systems and metallic
AnnexA1 for a specific form and format of information which
tanks. Such persons shall be registered professional engineers
must be provided by a vendor. This information consists of
or persons recognized as corrosion specialists or cathodic
historic performance data on a method and is mandated as part
protection specialists by NACE, if their professional activities
of the guide.
include suitable experiences in external corrosion control on
buried or submerged metallic piping and tanks.
4. Significance and Use
3.1.4 corrosion technician—a person possessing basic
4.1 This guide provides three methods for determining the
knowledge of corrosion and corrosion control, who is capable
suitability of a buried steel tank to be upgraded with cathodic
of performing routine, well defined work under the supervision
protection.
of the corrosion specialist/cathodic protection specialist.
4.2 This guide may be used to assess any UST, including
3.1.5 invasive procedure—a method of determining the
non-regulated USTs.
corrosion status of a tank by assessing the tank from the inside
4.3 This guide provides three alternative methods but does
as part of the upgrade procedure. Further, for the purposes of
not recommend any specific method or application. The
this guide, it does not require manned entry into the tank. (See
responsibility for selection of a method rests with the user.
non-invasive.)
4.4 This guide has specific requirements for vendor pro-
3.1.6 noninvasive procedure—a method of determining the
vided information which should be requested and reviewed by
corrosion status of a tank from the characteristics of its
the user.
surroundings with minimal entry into the tank. Further, for the
5. Permits, Plans and Tank Leak Testing
5.1 Prior to engaging in any activities relating to the
alteration, repair, or upgrade of any UST system, consult all
Available from Underwriters Laboratories (UL), Corporate Progress, 333
Pfingsten Rd., Northbrook, IL 60062.
necessary authorities to obtain any required permits.
Available from US Environmental Protection Agency, Office of Underground
5.2 Tank Leak Testing:
Storage Tanks, 401 “M” St. SW, Washington, DC 20460.
5.2.1 To establish that tanks are not leaking prior to assess-
Available from National Fire Protection Association (NFPA), 1 Batterymarch
Park, Quincy, MA 02269-9101. ment, they shall be assessed by a leak detection system. This
G158 – 98 (2004)
leak detection assessment alone is not sufficient to determine priatetothemethodofassessmentofthesuitabilityoftanksfor
that a tank is suitable for upgrading with cathodic protection upgrading with cathodic protection:
under this guide. 8.1.3.1 Stray dc current sources,
5.2.2 Atightness test or another release detection system in 8.1.3.2 Existing cathodic protection systems,
accordancewithNFPA329shallbeused.Anyreleasedetection 8.1.3.3 Steel product and vent piping and fittings, and
must be capable of detecting a leak from any portion of the 8.1.3.4 Adjacent subsurface metallic/steel-reinforced con-
tank that routinely contains product, and be independently crete structures.
evaluated and certified in accordance with Practice E1526 or 8.2 Preliminary Evaluation—Prior to assessing the tank, a
the equivalent. Leak detection results shall be provided to the preliminary site survey must be performed pursuant to Section
corrosion specialist/cathodic protection specialist. 8 and a tightness test must be performed pursuant to 5.2 to
5.2.3 This testing shall be accomplished within six months establish that the tank is not leaking.
prior to performing any of the assessment procedures.
9. Method A—Noninvasive with Primary Emphasis on
Statistical and Electrochemical Analysis of External
6. Required Approvals and Certifications
Site Environment Corrosion Data (1,2)
6.1 The corrosion assessment work carried out under this
9.1 Field and Laboratory Testing—Noninvasive with Pri-
guide shall be performed under the responsible direction of a
mary Emphasis on Statistical and Electrochemical Analysis of
corrosion specialist/cathodic protection specialist as defined in
External Site Environment Corrosion Data.
3.1.3.
9.1.1 Tests shall be conducted by, or as directed by a
6.2 The corrosion specialist/cathodic protection specialist
corrosion specialist/cathodic protection specialist.
shall certify to the tank owner or operator that the personnel
9.1.2 Field Testing Procedures—Tests to be performed shall
performingtheassessmentworkonthetankareknowledgeable
include, but are not limited to, the following:
of all the applicable procedures in this guide.
9.1.2.1 Stray Currents—Perform tests to detect the presence
6.3 The corrosion specialist/cathodic protection specialist
of stray currents at each tank site. This test shall consist of
shall certify to the tank owner or operator that all work was
measuring structure-to-soil potentials at right angles at a
performed in strict accordance with this guide.
minimum of two locations within the tank facilities and
observing the measurements for not less than2hata time
7. General Safety Requirements
when such influences are most likely to occur. The monitor
7.1 All personnel shall comply with applicable federal,
shall consist of a field data acquisition unit, with a minimum of
state, and local health and safety codes and regulations.
10-MV input impedance, used in conjunction with a stable
reference cell(s) placed in contact with the soil in the vicinity
8. Preliminary Site Survey
of the tank. The instrument shall measure and store structure-
8.1 A corrosion technician, under the responsible direction to-electrolytepotential(voltage)dataatleastevery5sthrough-
of the corrosion specialist/cathodic protection specialist, shall out the entire duration of field investigation at the site or for 2
obtain tank site specific information as appropriate to the h, whichever is greater. If variations of 650 mV or greater are
method of assessment to be used. measuredduringthetestperiod,make24-hrecordingmeasure-
8.1.1 Facility Information: ments to confirm stray current effects.
8.1.1.1 Address or location, and 9.1.2.2 Tank Information:
8.1.1.2 Name and telephone number of owner and operator (a) Locate all tanks and confirm materials of construction,
contact personnel. age, capacity, and dimensions. Produce detailed site sketches
8.1.2 Tank and Piping Details: describing the layout of the UST system and above grade
8.1.2.1 Number and capacity, pertinent details for each site.
8.1.2.2 Location and dimensions, (b) Determine the presence and extent of internal corrosion
8.1.2.3 Age, immediately below the fill riser. If the depth of corrosion
8.1.2.4 Material of construction,
penetration in the tank shell exceeds 50 % of the tank wall
8.1.2.5 Electrical isolation, thickness, the UST shall be declared to have failed the test and
8.1.2.6 Type of product stored, the procedure.
8.1.2.7 Names of site contact personnel, (c)
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.