“Soil sampling” is a term that the general public associates simply with the collection of a small quantity of loose soil material extracted from a soil pit. However, soil science distinguishes several sampling approaches which are specific for collecting soil materials in different states or under different conditions according to the objectives of the study and parameters to be investigated. The major soil sampling approaches are summarized in the following paragraphs.

Dig

Method of sampling where a portion of the subsurface is excavated mechanically or by hand and brought to the surface in a bucket or on a shovel. This method normally yields samples with sampling quality class E.

Remotely dry

Method of sampling where the material is loosened at depth and the loosened soil is brought to the surface via screwing of the drill or is loosened with compressed air and brought to the surface to be sampled there. One of the methods used is drilling with an auger. This method normally yields samples with sampling quality class E.

Remotely wet

Method of sampling where the material is loosened at depth or sprayed loose. The loosened material is rinsed upwards in an unspecified way. It is sampled at the surface by separating the liquid from the material. The method is used for counter flush drilling, for the geodoff, with rotary drilling and with impact drilling. This method is not intended for airlifts, piston drills and straight flush drilling. For these drilling types the way in which the material is flushed to the surface, is specified. This method normally yields samples with sampling quality class E.

Remotely wet on the outside

Method of sampling where the material is loosened at depth or the loosened material is pumped upwards via the hollow drill rods. It is sampled at the surface by separating liquid and material from each other. This method is used in airlifting and mechanical piston drilling. This method normally yields samples with sampling quality class E.

Remotely wet on the inside

Method of sampling where the material is loosened at depth or the loosened material is pumped upwards in between the drill rods and the side of the borehole . It is sampled at the surface by separating liquid and material from each other. This method is used in straight flush drilling. This method normally yields samples with sampling quality class E.

Gripping at depth

Method of sampling where the material is taken out at depth with a gripper. This method is used in grapple drilling. This method normally yields samples with sampling quality class D or E. Which of the two classes is accurate is determined by the cohesion and moisture of the soil.

Cores at depth

Method of sampling where a column of material at depth is collected in a container with a special drill bit or with rotating nozzles. The sampled soil is pulled or cut loose and brought to the surface. This method is used in core drilling, rotary core drilling and when one uses the Sherbrooke sampler. This method normally yields samples with sampling quality class A,B,C or D. Which class applies is determined by the type of sampling device, the drilling technique and the cohesion and moisture of the soil.

Stir at depth

Method of sampling where the material is loosened at depth, is collected in the device and brought to the surface with the same device. This method is used in drilling with the bucket system, rotary drilling by hand, pulse drilling, with the VanderStaay drill and with the hand-operated piston drill. This method yields samples with sampling quality class E to D. Which class applies is determined by the drilling technique and the cohesion and moisture of the material.

Sticking out at depth

Method of sampling where a column of material is cut out or pulled out at depth, collected in a container and brought to the surface in the same container. This method is used with the Ackermann device, the VanderStaay drill, the Aqualock sampler, the Beeker sampler, the Begemann sampler, the Dachnovsky device, the dropcorer, the DLDS, the foil sampler, the soil column cylinder, the gouge auger, the sample ring sampler, the MOSTAP, the pistoncorer, the (peat) profile sampler, the ram gouge auger, the sonic drill, the spit sampler, the core sampler, the vibratory flip, the VanderHorst sampler, the vibrocorer, the window sampler and the Zenkovitch drill. Normally yields samples with sampling quality class A,B,C or D. Which class applies is determined by the type of sampling device, the drilling technique and the cohesion and moisture of the material.

References

  • BRO-Catalogus Geologisch booronderzoek versie 0.99 - 25 maart 2020
 
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