ASTM_E_2856_-_13.pdf

Designation:E285613Standard Guide forEstimation of LNAPL Transmissivity1This standard is issued under the fixed designation E2856;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 guide provides field data collection and calculationmethodologies for the estimation of light non-aqueous phaseliquid(LNAPL)transmissivity in unconsolidated porous sedi-ments.The methodologies presented herein may,or may notbe,applicable to other hydrogeologic regimes(for example,karst,fracture flow).LNAPL transmissivity represents thevolume of LNAPL(L3)through a unit width(L)of aquifer perunit time(t)per unit drawdown(L)with units of(L2/T).LNAPL transmissivity is a directly proportional metric forLNAPL recoverability whereas other metrics such as apparentLNAPL thickness gauged in wells do not exhibit a consistentrelationship to recoverability.The recoverability for a givengauged LNAPL thickness in a well will vary between differentsoil types,LNAPL types or hydrogeologic conditions.LNAPLtransmissivity accounts for those parameters and conditions.LNAPL transmissivity values can be used in the following fiveways:(1)Estimate LNAPL recovery rate for multiple tech-nologies;(2)Identify trends in recoverability via mapping;(3)Applied as a leading(startup)indicator for recovery;(4)Applied as a lagging(shutdown)indicator for LNAPL recov-ery;and(5)Applied as a robust calibration metric for multi-phase models(Hawthorne and Kirkman,2011(1)2and ITRC(2).The methodologies for LNAPL transmissivity estimationprovided in this document include short-term aquifer testingmethods(LNAPL baildown/slug testing and manual LNAPLskimming testing),and long-term methods(that is,LNAPLrecovery system performance analysis,and LNAPL tracertesting).The magnitude of transmissivity of any fluid in thesubsurface is controlled by the same variables(that is,fluidpore space saturation,soil permeability,fluid density,fluidviscosity,the interval that LNAPL flows over in the formationand the gravitational acceleration constant).A direct math-ematical relationship exists between the transmissivity of afluid and the discharge of that fluid for a given induceddrawdown.The methodologies are generally aimed at measur-ing the relationship of discharge versus drawdown for theoccurrence of LNAPL in a well,which can be used to estimatethe transmissivity of LNAPL in the formation.The focus,therefore,is to provide standard methodology on how to obtainaccurate measurements of these two parameters(that is,discharge and drawdown)for multi-phase occurrences toestimate LNAPL transmissivity.1.2 Organization of this Guide:1.2.1 Section 2 presents documents referenced.1.2.2 Section 3 presents terminology used.1.2.3 Section 4 presents significance and use.1.2.4 Section 5 presents general information on four meth-ods for data collection related to LNAPL transmissivity calcu-lation.This section compares and contrasts the methods in away that will allow a user of this guide to assess which methodmost closely aligns with the site conditions and available datacollection opportunities.1.2.5 Sections 6 and 7 presents the test methods for each ofthe four data collection options.After reviewing Section 5 andselecting a test method,a user of this guide shall then proceedto the applicable portion of Sections 6 and 7 which describesthe detailed test methodology for the selected method.1.2.6 Section 8 presents data evaluation methods.Afterreviewing Section 5 and the pertinent test method section(s)ofSections 6 and 7,the user of this guide shall then proceed to theapplicable portion(s)of Section 8 to understand the method-ologies for evaluation of the data which will be collected.It ishighly recommended that the test methods and data evaluationprocedures be understood prior to initiating data collection.1.3 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 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.1.5 This document is applicable to wells exhibiting LNAPLconsistently(that is,LNAPL transmissivity values above zero).This methodology does not substantiate zero LNAPL transmis-sivity;rather the lack of detection of LNAPL within the well1This guide is under the jurisdiction ofASTM Committee E50 on EnvironmentalAssessment,Risk Management and Corrective Action and is the direct responsibil-ity of Subcommittee E50.04 on Corrective Action.Current edition approved April 1,