ASTM-E2531:2006 Edition

1.1 This guide applies to sites with LNAPL present as residual, free, or mobile phases, and anywhere that LNAPL is a source for impacts in soil, ground water, and soil vapor. Use of this guide may show LNAPL to be present where it was previously unrecognized. Information about LNAPL phases and methods for evaluating its potential presence are included in , guide terminology is in Section , and technical glossaries are in . Fig. 1 is a flowchart that summarizes the procedures of this guide.

1.2 This guide is intended to supplement the conceptual site model developed in the RBCA process (Guides E 1739 and E 2081) and in the conceptual site model standard (Guide E 1689) by considering LNAPL conditions in sufficient detail to evaluate risks and remedial action options.

1.3 Federal, state, and local regulatory policies and statutes should be followed and form the basis of determining the remedial objectives, whether risk-based or otherwise. Fig. 1 illustrates the interaction between this guide and other related guidance and references.

1.4 Petroleum and other chemical LNAPLs are the primary focus of this guide. Certain technical aspects apply to dense NAPL (DNAPL), but this guide does not address the additional complexities of DNAPLs.

1.5 The composite chemical and physical properties of an LNAPL are a function of the individual chemicals that make-up an LNAPL. The properties of the LNAPL and the subsurface conditions in which it may be present vary widely from site to site. The complexity and level of detail needed in the LCSM varies depending on the exposure pathways and risks and the scope and extent of the remedial actions that are needed. The LCSM follows a tiered development of sufficient detail for risk assessment and remedial action decisions to be made. Additional data collection or technical analysis is typically needed when fundamental questions about the LNAPL cannot be answered with existing information.

1.6 This guide does not develop new risk assessment protocols. It is intended to be used in conjunction with existing risk-based corrective action guidance (for example, Guides E 1739 and E 2081) and regulatory agency requirements (for example, USEPA 1989, 1991, 1992, 1996, 1997).

1.7 This guide assists the user in developing an LCSM upon which a decision framework is applied to assist the user in selecting remedial action options.

1.8 The goal of this guide is to provide sound technical underpinning to LNAPL corrective action using appropriately scaled, site-specific knowledge of the physical and chemical processes controlling LNAPL and the associated plumes in ground water and soil vapor.

1.9 This guide provides flexibility and assists the user in developing general LNAPL site objectives based on the LCSM. This guide recognizes LNAPL site objectives are determined by regulatory, business, regional, social, and other site-specific factors. Within the context of the Guide E 2081 RBCA process, these factors are called the technical policy decisions.

1.10 Remediation metrics are defined based on the site objectives and are measurable attributes of a remedial action. Remediation metrics may include environmental benefits, such as flux control, risk reduction, or chemical longevity reduction. Remediation metrics may also include costs, such as installation costs, energy use, business impairments, waste generation, water disposal, and others. Remediation metrics are used in the decision analysis for remedial options and in tracking the performance of implemented remedial action alternatives.

1.11 This guide does not provide procedures for selecting one type of remedial technology over another. Rather, it recommends that technology selection decisions be based on the LCSM, sound professional judgment, and the LNAPL site objectives. These facets are complex and interdisciplinary. Appropriate user knowledge, skills, and judgment are required.

1.12 This guide is not a detailed procedure for engineering analysis and design of remedial action systems. It is intended to be used by qualified professionals to develop a remediation strategy that is based on the scientific and technical information contained in the LCSM. The remediation strategy should be consistent with the site objectives. Supporting engineering analysis and design should be conducted in accordance with relevant professional engineering standards, codes, and requirements.

1.13 ASTM standards are not federal or state regulations; they are voluntary consensus standards.

1.14 The following principles should be followed when using this guide:

1.14.1 Data and information collected should be relevant to and of sufficient quantity and quality to develop a technically-sound LCSM.

1.14.2 Remedial actions taken should be protective of human health and the environment now and in the future.

1.14.3 Remedial actions should have a reasonable probability of meeting the LNAPL site objectives.

1.14.4 Remedial actions implemented should not result in greater site risk than existed before taking actions.

1.14.5 Applicable federal, state, and local regulations should be followed (for example, waste management requirements, ground water designations, worker protection).

1.15 This guide is organized as follows:

1.15.1 Section 2 lists associated and pertinent ASTM documents.

1.15.2 Section 3 defines terminology used in this guide.

1.15.3 Section 4 includes a summary of this guide.

1.15.4 Section 5 provides the significance and use of this guide.

1.15.5 Section 6 presents the components of the LCSM.

1.15.6 Section 7 offers step-by-step procedures.

1.15.7 Nonmandatory appendices are supplied for the following additional information:

1.15.7.1 Appendix X1 provides additional LNAPL reading.

1.15.7.2 Appendix X2 provides an overview of multiphase modeling.

1.15.7.3 Appendix X3 provides example screening level calculations pertaining to the LCSM.

1.15.7.4 Appendix X4 provides information about data collection techniques.

1.15.7.5 Appendix X5 provides example remediation metrics.

1.15.7.6 Appendix X6 provides two simplified examples of the use of the LNAPL guide.

1.15.7.7 Appendix X7 and Appendix X8 are glossaries of technical terminology relevant for LNAPL decision-making.

1.15.8 A reference list is included at the end of the document.

1.16 The appendices are provided for additional information and are not included as mandatory sections of this guide.

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.

This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word ‘Standard’ in the title of this document means only that the document has been approved through the ASTM consensus process.

PDF Catalog

PDF Pages	PDF Title
1	Scope
3	Referenced Documents Terminology
4	FIG. 1
5	FIG. 2
6	FIG. 3
7	FIG. 4
8	FIG. 5
10	Summary of Guide
11	TABLE 1
12	Significance and Use TABLE 2
13	Components of the LNAPL Conceptual Site Model
15	Procedure
16	FIG. 6
19	Keywords X1. ADDITIONAL LNAPL READING X1.1 X1.2 X1.3 X1.4 X1.5 X1.6 X1.7 X1.8 X1.9
20	X1.10 X1.11 X1.12 X1.13 X1.14 X1.15 X1.16 X1.17 X1.18 X1.19 X1.20 X1.21 X1.22 X1.23 X1.24 X1.25 X1.26 X1.27 X1.28 X1.29 X1.30 X1.31 X1.32 X1.33 X1.34 X1.35 X1.36
21	X1.37 X1.38 X1.39 X1.40 X1.41 X1.42 X1.43 X1.44 X1.45 X1.46 X1.47 X1.48 X1.49 X1.50 X1.51 X1.52 X1.53 X1.54 X1.55 X1.56 X1.57 X1.58 X1.59 X1.60
22	X1.61 X1.62 X1.63 X1.64 X1.65 X1.66 X1.67 X1.68 X1.69 X1.70 X1.71 X1.72 X1.73 X1.74 X1.75 X1.76 X1.77 X1.78 X1.79 X1.80
23	X1.81 X1.82 X1.83 X1.84 X1.85 X1.86 X1.87 X1.88 X1.89 X1.90 X1.91 X1.92 X1.93 X1.94 X1.95 X1.96 X1.97 X1.98 X1.99 X1.100 X1.101 X1.102 X1.103
24	X1.104 X1.105 X1.106 X1.107 X1.108 X1.109 X1.110 X1.111 X1.112 X1.113 X1.114 X1.115 X1.116 X1.117 X1.118 X1.119 X1.120 X1.121 X1.122 X1.123 X1.124 X1.125 X1.126 X1.127 X1.128 X1.129
25	X1.130 X1.131 X1.132 X1.133 X1.134 X1.135 X1.136 X1.137 X1.138 X1.139 X1.140 X1.141 X1.142 X1.143 X1.144 X1.145 X1.146 X1.147 X1.148 X1.149 X1.150
26	X2. OVERVIEW OF MULTIPHASE MODELING X2.1 Introduction X2.2 Scope X2.3 Precautionary Statements X2.4 Multiphase Model Selection Criteria
27	TABLE X2.1
28	X2.5 Physical Basis for Multiphase Modeling
29	X2.6 Specific Discharge and Seepage Velocity X2.7 LNAPL Saturation X2.8 Wetting and Nonwetting Phases
30	X2.9 Types of Multiphase Models X2.10 Types of Problems that Can Be Solved X2.11 Commonly Assumed Modeling Conditions
31	X2.12 Multiphase Modeling Summary X3. EXAMPLE CALCULATIONS X3.1 Introduction X3.2 LNAPL Distribution
33	FIG. X3.1
35	FIG. X3.2
36	X3.3 FIG. X3.3 FIG. X3.4 FIG. X3.5
37	X4. DATA COLLECTION CONSIDERATIONS AND RESOURCES X4.1 Introduction X4.2 Scope X4.3 X4.4 X4.5 X4.6 X4.7 Delineation and Parameter Determination X4.8
38	TABLE X4.1
39	X4.9 X4.10 Coring and Laboratory Testing
40	X4.11 Basic Soil Properties X4.12 LNAPL Saturation X4.13 Residual LNAPL Saturation X4.14 Relative Permeability X4.15 Intrinsic Permeability to Phases of Interest X4.16 Physical Fluid Properties X4.17 Chemical Analyses
41	X5. REMEDIATION METRICS X5.1 Introduction X5.2 Scope
42	TABLE X5.1 TABLE X5.2
43	X5.3 Procedure X6. EXAMPLE USE OF THE LNAPL GUIDE X6.1 Introduction X6.2 Purpose X6.3 Precautionary Statement X6.4 Example 1 TABLE X5.3
44	TABLE X6.1 TABLE X6.2
45	FIG. X6.1
46	FIG. X6.2
47	FIG. X6.3
48	TABLE X6.3 TABLE X6.4 TABLE X6.5
49	TABLE X6.6
50	TABLE X6.7
51	X6.5 Example 2
52	FIG. X6.5
53	FIG. X6.6
54	FIG. X6.7
55	FIG. X6.8 FIG. X6.9 TABLE X6.8
56	FIG. X6.10
57	FIG. X6.4
59	TABLE X6.9
60	TABLE X6.10
61	TABLE X6.11
62	FIG. X6.11
63	X7. GLOSSARY OF TECHNICAL TERMS FOR CHARACTERIZING IMMISCIBLE FLUIDS IN SOIL AND GEOLOGIC MEDIA X7.1 air saturation, n X7.2 Brooks-Corey capillary parameters, n X7.3 bubbling pressure, n X7.4 capillarity, n X7.5 capillary action, n X7.6 capillary forces, n X7.7 capillary head, n X7.8 capillary parameters, n X7.9 capillary pressure, n X7.10 contact angle, n X7.11 critical capillary head, n X7.12 displacement pressure, n X7.13 drainage, n X7.14 effective porosity, n X7.15 effective saturation, n X7.16 entrapped air, n X7.17 fluid density, n X7.18 fluid potential, n
64	X7.19 fluid pressure, n X7.20 fluid pressure head, n X7.21 fluid saturation, n X7.22 fluid viscosity, n X7.23 free water, n X7.24 hysteresis, n X7.25 imbibition, n X7.26 immiscible displacement, n X7.27 immiscible fluids, n X7.28 immobile LNAPL, n X7.29 interfacial tension, n X7.30 irreducible saturation, n X7.31 LNAPL conductivity, n X7.32 LNAPL mobility, n X7.33 LNAPL plume stability, n X7.34 LNAPL potentiometric gradient, n X7.35 LNAPL potentiometric head, n X7.36 LNAPL potentiometric surface, n X7.37 LNAPL pressure head, n X7.38 LNAPL saturation, n X7.39 LNAPL saturation profile, n
65	X7.40 LNAPL specific discharge, n X7.41 LNAPL specific yield, n X7.42 LNAPL transmissivity, n X7.43 matric potential, n X7.44 non-wetting fluid, n X7.45 non-wetting fluid entry pressure, n X7.46 non-wetting fluid entry pressure head, n X7.47 oil conductivity, n X7.48 pore-size distribution index, n X7.49 porous medium, n X7.50 potentiometric gradient, n X7.51 potentiometric head, n X7.52 potentiometric surface, n X7.53 primary porosity, n X7.54 relative permeability, n X7.55 representative elemental volume, n X7.56 residual fluid saturation, n X7.57 residual LNAPL saturation, n X7.58 residual water saturation, n X7.59 retention curve, n
66	X7.60 scanning curves, n X7.61 secondary porosity, n X7.62 soil tension, n X7.63 surface tension, n X7.64 tensiometer, n X7.65 tertiary porosity, n X7.66 van Genuchten capillary parameters, n X7.67 water content, n X7.68 water saturation, n X7.69 wettability, n X7.70 wetting fluid, n X8. GLOSSARY OF TECHNICAL TERMS FOR CHARACTERIZING THE NATURE AND MIGRATION OF CHEMICALS DERIVED FROM LNAPL IN SOIL AND GEOLOGIC MEDIA X8.1 adsorbed phase, n X8.2 adsorption, n X8.3 advection, n X8.4 aerobic, adj X8.5 anaerobic, adj X8.6 aqueous phase, n X8.7 aquifer, n X8.8 aquifer transmissivity, n X8.9 aquitard, n
67	X8.10 biodegradation, n X8.11 bulk density, n X8.12 chemical mass flux, n X8.13 chemical mass losses, n X8.14 Darcy velocity, n X8.15 dispersion, n X8.16 dispersion coefficient, n X8.17 dispersivity, n X8.18 effective fluid conductivity, n X8.19 effective fluid transmissivity, n X8.20 effective porosity, n X8.21 effective solubility, n X8.22 fluid density, n X8.23 fraction of organic carbon, n X8.24 Freundlich isotherm, n X8.25 grain density, n X8.26 groundwater, n X8.27 groundwater flow net, n X8.28 groundwater mass flux, n
68	X8.29 hydraulic conductivity, n X8.30 linear pore velocity, n X8.31 longitudinal dispersion, n X8.32 mass content, n X8.33 molar concentration, n X8.34 mole, n X8.35 mole fraction, n X8.36 Monte Carlo simulation, n X8.37 organic carbon partitioning coefficient (Koc), n X8.38 partitioning, n X8.39 partitioning coefficient, n X8.40 perched water table, n X8.41 phase, n X8.42 saturated zone, n X8.43 solubility, n X8.44 transverse dispersion, n X8.45 vapor diffusion efficiency, n X8.46 vapor mass flux, n X8.47 water table, n
69	X8.48 water table gradient, n REFERENCES

Standard Title	E2531-06 Standard Guide for Development of Conceptual Site Models and Remediation Strategies for Light Nonaqueous-Phase Liquids Released to the Subsurface
Published Code	ASTM
Publication Date	2006
Pages Count	69
ICS Codes	13.080.05 - Examination of soils in general