ASTM_D_1987_-_07_2012.pdf

Designation:D198707(Reapproved 2012)Standard Test Method forBiological Clogging of Geotextile or Soil/Geotextile Filters1This standard is issued under the fixed designation D1987;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method is used to determine the potential for,and relative degree of,biological growth which can accumulateon geotextile or geotextile/soil filters.1.2 This test method uses the measurement of flow ratesover an extended period of time to determine the amount ofclogging.1.3 This test method can be adapted for nonsaturated as wellas saturated conditions.1.4 This test method can use constant head or falling headmeasurement techniques.1.5 This test method can also be used to give an indicationas to the possibility of backflushing and/or biocide treatmentfor remediation purposes if biological clogging does occur.1.6 The values in SI units are to be regarded as the standard.The values provided in inch-pound units are for informationonly.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 applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for GeosyntheticsD4491 Test Methods for Water Permeability of Geotextilesby PermittivityD5101 Test Method for Measuring the Filtration Compat-ibility of Soil-Geotextile SystemsG22 Practice for Determining Resistance of Plastics toBacteria(Withdrawn 2002)3E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 geotextile,na permeable geosynthetic comprisedsolely of textiles.3.1.2 permeability,nthe rate of flow of a liquid under adifferential pressure through a material.3.1.2.1 DiscussionIn geotextiles,permeability refers tohydraulic conductivity.3.1.3 permittivity,()(t1),nof geotextiles,the volumetricflow rate of water per unit,in a cross sectional area head underlaminar flow conditions.3.1.4 aerobic,na condition in which a measurable volumeof air is present in the incubation chamber or system.3.1.4.1 DiscussionIn geotextiles,this condition can poten-tially contribute to the growth of micro-organisms.3.1.5 anaerobic,na condition in which no measurablevolume of air is present in the incubation chamber or system.3.1.5.1 DiscussionIn geotextiles,this condition cannotcontribute to the growth of microorganisms.3.1.6 back flushing,na process by which liquid is forcedin the reverse direction to the flow direction.3.1.6.1 DiscussionIn other drainage application areas,this process is commonly used to free clogged drainagesystems of materials that impede the intended direction of flow.3.1.7 biocide,na chemical used to kill bacteria and othermicroorganisms.3.2 For definitions of other terms used in this test method,refer to Terminology D123 and D4439.4.Summary of Test Method4.1 A geotextile filter specimen or geotextile/soil filtercomposite specimen is positioned in a flow column so that a1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Properties.Current edition approved July 1,2012.Published July 2012.Originally approvedin 1991.Last previous edition approved in 2007 as D1987 07.DOI:10.1520/D1987-07R12.2For referenced 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 onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 designated liquid flows through it under either constant orfalling head conditions.4.1.1 The designated liquid might contain micro-organismsfrom which biological growth can occur.4.2 Flow rate is measured over time,converted to eitherpermittivity or permeability,and reported according.4.2.1 Between readings,the test specimen can be allowed tobe in either nonsaturated or saturated conditions.4.2.2 Back flushing can be introduced from the directionopposite to the intended flow direction and evaluated accord-ingly.4.2.3 Biocide can be introduced with the back flushingliquid,or introduced within the test specimen,and evaluatedaccordingly.5.Significance and Use5.1 This test method is performance oriente