ASTM E 3281 : 2026

1.1Many contaminants (such as petroleum products and coal tar) are emplaced in sediment in the form of an immiscible liquid known as a non-aqueous phase liquid (NAPL). NAPL can either be a light non-aqueous phase liquid (LNAPL) that is less dense than water or a dense non-aqueous phase liquid (DNAPL) that is denser than water.

1.2This guide is designed for general application at a wide range of sediment sites where NAPL is present or suspected to be present in the sediment. This guide describes a framework to use field screening methods, specifically visual observations and the results of sediment-water shake tests, to categorize the relative amount of NAPL contained in a sediment sample. This categorization can then be utilized to select collocated sediment samples for laboratory testing to determine if the NAPL in the selected sample interval is mobile or immobile at the pore scale, or for any other chemical or physical testing.

1.3This guide does not address methods and means of sample collection (see Guide E3268) or various sediment sample physical testing and chemical analytical methods (see Guide E3163).

1.4This guide concerns the identification of sediment samples to submit for laboratory NAPL mobility testing, the results of which are used in evaluating the advective movement of NAPL in sediment. Ebullition-facilitated transport (EFT) of NAPL and associated contaminants (NAPL/contaminants) from the sediment into the surface water column by biogenic gas bubbles generated within the sediment is not within the scope of this guide. The measurement and evaluation of ebullition gas and NAPL/contaminant fluxes are discussed in Guides E3300 and E3447. Processes associated with NAPL movement due to erosion (for example, caused by propeller wash) are also not within the scope of this guide.

1.5Petroleum hydrocarbon, coal tar, and other tar NAPLs (including fuels, oils, and creosote) are the primary focus of this guide. These forms of contamination are commonly related to historical operations at petroleum refineries, petroleum distribution terminals, manufactured gas plants, and various large industrial sites.

1.6Related ASTM Standards—This guide is related to several other guides that cover various aspects of NAPL mobility and migration in sediment. Guide E3248 provides guidance on NAPL emplacement mechanisms in sediment and the differences between NAPL in sediment and upland soil; this guide also outlines a framework to be used to determine whether a NAPL movement assessment should be performed at a sediment site. Guide E3268 provides guidance on the collection, field screening, and handling of sediment samples that are representative of in situ conditions for laboratory geotechnical and NAPL mobility testing. Guide E3282 discusses metrics (for various lines of evidence (LOEs)) used to evaluate whether NAPL is mobile or immobile at the pore scale; and if the NAPL is mobile, this guide describes other metrics (using additional LOEs) to evaluate whether NAPL is migrating or stable at the NAPL body scale. Guide E3282 also presents example decision analysis frameworks for evaluating whether NAPL is immobile or mobile at the pore scale, and if mobile, stable or migrating at the NAPL body scale. Guide E3300 discusses ebullition fundamentals and how to obtain ebullition gas and NAPL/contaminant EFT fluxes (which can be used to estimate NAPL/contaminant loading to the surface water body). Guide E3447 discusses the use of flux chambers to measure EFT fluxes, which can be used to estimate NAPL/contaminant loading to the surface water body.

1.7Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.8This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.9This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.