ASTM International

Standard Practice for Direct Push Hydraulic Logging for Profiling Variations of Permeability in Soils
 N D8037/D8037M

Annotation

This practice describes a method for rapid delineation of variations in formation permeability in the subsurface using an injection logging tool. Clean water is injected from a port on the side of the probe as it is advanced at approximately 2cm/s into virgin soils. Logging with the injection tool is typically performed with direct push equipment, however other drilling machines may be modified to run the logs by direct push methods (for example, addition of a suitable hammer and/or hydraulic ram systems). Injection logs exceeding 100 ft [30m] depth have been obtained. Direct push methods are not intended to penetrate consolidated rock and may encounter refusal in very dense formations or when cobbles or boulders are encountered in the subsurface. However, injection logging has been performed in some semi-consolidated or soft formations.

This standard practice describes how to obtain a real time vertical log of injection pressure and flow rate with depth. The data obtained is indicative of the variations of permeability in the subsurface and is typically used to infer formation lithology. The person(s) responsible for review, interpretation and application of the injection logging data should be familiar with the logging technique as well as the soils, geology and hydrogeology of the area under investigation.

The injection logging system may be operated with a built in electrical conductivity sensor to provide additional real time information on stratigraphy and is essential for targeting test zones. Other sensors, such as fluorescence detectors (Practice D6187), a membrane interface probe (Practice D7352) or a cone penetration tool (Test Method D5778) may be used in conjunction with injection logging to provide additional information. The use of the injection logging tool in concert with an electrical conductivity array or cone penetration tool is highly recommended (although not mandatory) to further define hydrostratigraphic conditions, such as migration pathways, low permeability zones (for example, aquitards) and to guide confirmation sampling. The EC log and injection pressure log may be compared in some settings to identify the presence of ionic contaminants or ionic injectates used for remediation.