Monitoring of the mobility of toxic components of mining must be based on reliable analytical methods
The analysis of soil and sediment samples in mining industry is require for both when a baseline study is carried out before environmental permiting and during the life- of – mine to monitor the potential effects of mining and processing of the ore.
Labtium offers a wide range of services using modern analytical equipment. We provide a comprehensive set of methods for following up the state of the environment, assessing contamination and monitoring environmental effects.
In addition to the analysis of metal concentrations and inorganic hazardous substances in soil and sediment samples, our services also include a wide variety of weak extractions, which can be used to assess the forms taken by elements, plus the chemical characteristics and pollution load of the soil.
Using standard leaching behavior tests we carry out basic determination of industrial by-products, wastes, and polluted soil. We also conduct studies on placement, and draw up plans for utilization, in accordance with statutes 331/2013, 591/2006 and 403/2009 of the Finnish government (see Side products and tailings testing).
Most of the methods we use in sample pretreatment and analytical methods are internationally standardised.
We offer wide range of drying (eg. Freeze drying), crushing, pulverising, sieving and ashing methods for soil and sediment samples.
Total analysis of elements
Labtium recomends that soil-, sediment- and ash samples are extracted by hot aqua regia. Dissolution in hot aqua regia (Modified ISO-11466) is suitable for mineral samples when one is determining total metal concentrations with respect to environmental loading. Measurements are made by ICP-OES / ICP-MS (512P/512PM)
When determing the total concentrations of organic sediment, humus and peat samples with respect to environmental loading, decomposition with nitric acid is recomendable. We offer two different methods: Decomposition with nitric acid in a microwave oven (EPA 3051) and ”in-house” Decomposition with nitric acid at 90 °C. Measurements are made by ICP-OES / ICP-MS and mercury by CV-AFS (503P/503PM)
Weak excractions gives information about the portion of toxic elements bound to the most mobile phases, the speciation of elements and the chemical characteristics of the soils and sediments. Extractions are performed in room temperature in specified solid to liquid ratios. Samples are shaked a given time and filtrated. Eluates are measured by ICP-OES/ ICP-MS techniques. Properties of sample and specified extraction conditions have a great influence to the repeatability and uncetainity of weak extractions.
In addition to traditional weak extarctions Labtium offers extraction series and leaching tests. Extraction series gives information how harmful species are bound in different phases of soils and sediments.
The cation exchange capacity (CEC) and pH value of soil samples can be determined with non-pH-buffered weak extractions. The CEC can be applied to nutrient analysis of soil, to planning the utilization of soil improvement agents, and to earthworks.
For determination of individual elements or the characteristics of a sample we offer a number special determinations based on a variety of analyses and types of equipment.