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Soil Sampling

• Coring equipment to sample soil on volatilesTraditional method: – Closed stainless steel tubes with filler blocks that avoid

head space and evaporation for soil with volatiles located deeper than 0.5m

– Additionally sample tube is wrapped in aluminium foil and cooled

– Preferably horizontal transportation, to avoid higher concentrations at one side of the tube

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Soil Sampling

• Methanol or sodiumthiosulphate method– Details can be found in US-

EPA 5035A-2002 (both methods) or applicable ISO standards as ISO 22155 and ISO18512

– Decontaminate the corer

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Soil Sampling

– Push or hammer the soil corer into the larger sample.

– Overfill the corer

– Push a second time if the soil is very sticky (like here in Haslemere)

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Soil Sampling

– Use plunger to push the 16ml of soil in the jar with 25 grams methanol or sodiumthiosulphate.

• To allow the lab to express the concentrations found as based on dry weight a black capped coring ring should be sent with the methanol stored samples

– Or wrap chemical analysis sticker around capped sample and store sample in a cool location or freeze. - Extraction is done in the laboratory

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Soil Sampling

– In the laboratory the methanol or sodiumthiosulphate will be analysed for volatiles.

– A criticism: there are much better extraction liquids for volatiles. Use the “freeze method”

– Be aware of safety risks: Methanol is highly flammable and toxic for humans. Chemicals in the field !?