What is this ISO 21268‑3 - up-flow percolation test for soil about?
ISO 21268‑3 is the third part of the multi-series on soil quality and discusses the chemical and ecotoxicological testing of soil. ISO 21268‑3 specifies a test that is aimed at determining the leaching behaviour of inorganic and organic substances from soil and soil-like materials. The method is a once-through up-flow percolation test under standardized conditions of flow rate. The material is leached under dynamic hydraulic conditions.
ISO 21268‑3 has been developed to measure the release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. ISO 21268‑3 provides a test method with eluates, which can subsequently be characterized by physical, chemical, and ecotoxicological methods in accordance with existing standard methods. The results of eluate analysis are presented as a function of the liquid/solid (L/S) ratio.
Note 1: The test is not suitable for substances that are volatile under ambient conditions.
Note 2: ISO 21268‑3 does not address issues related to health and safety. It only determines the leaching properties as outlined.
Who is ISO 21268‑3 - up-flow percolation test for soil for?
ISO 21268‑3 on the up-flow percolation test for soil is useful for:
- Ecologists and conservationists
- Soil testing laboratories
- Landowners
- Production units that release waste into waterbodies
Why should you use ISO 21268‑3 - up-flow percolation test for soil?
The release of soluble substances upon contact with water is regarded as the main mechanism of release, that results in a potential risk to the environment during the use or disposal of materials. The intent of these tests is to identify the leaching properties of materials. The complexity of the leaching process makes simplifications necessary.
ISO 21268‑3 provides a test that is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of soil. Additional leaching tests are needed for that extended goal.
The test procedure described in ISO 21268‑3 belongs to basic characterization tests. ‘Basic characterization’ tests are used to obtain information on the short- and long-term leaching behaviour and characteristic properties of materials. Liquid/solid (L/S) ratios, leachant composition, factors controlling leachability, such as pH, redox potential, complexing capacity, the role of dissolved organic carbon (DOC), ageing of material and physical parameters, are addressed in these tests.
What’s changed since the last update?
BS EN ISO 21268‑3:2019 supersedes ISO/TS 21268-3:2007, which is withdrawn. BS EN ISO 21268‑3:2019 includes some technical changes with respect to ISO/TS 21268-3:2007.
These include:
- Flow rate of 30 cm/d has been added as an option based on robustness testing
- 1 "General", 11.2 "Validation trials performed in Japan" and 12.3 "Validation results obtained in Germany (DIN 19528)" have been added
- 2 "Particle size distribution" has been deleted
- A new informative Annex C "Calculation of centrifugation duration depending on centrifugation speed and rotor dimensions" has been added
- References in Clause 2 and Bibliography has been updated