The term “soil” in the Ukrainian language defines two concepts: in engineering geology and engineering soil science, the generalized name of various rocks, which are the basis or material for the construction of roads, bridges, houses, etc., and the well-known notion of agro-soil science is a natural (or artificial) mixture of mineral shares of soil-forming species and specific organic substances with different amounts of water and air that capable of providing plant life that forms the surface layer of the earth’s crust.
It should be noted that in agricultural production the concept of land as an object and means of production is much broader than the concept of soil, since it includes a complex of environmental factors, and in a broad sense the earth is any part of the earth’s surface, all lands, regardless of their purpose, economic use and differences in the legal regime.
In the framework of forensic soil science expertise, objects of soil, soil and mineral or soil and technogenic origin (soils, rocks of natural or artificial origin, including some building materials – clays, sands, stones, slag, chalk, gypsum, bricks or building solutions contain sand, chalk, etc.). Expert studies of such facilities are conducted with the aim of establishing various actual data (circumstances) in a particular case.
The main tasks of the experts of KFI during the soil science expertise are the identification of micro- layers (particles) of soil origin on the carriers, determining their nature, establishing common generic (group) belonging to the samples provided, the origin of the soil on the carrier objects from a certain section of the terrain (another place of the event), as well as the establishment of a mechanism for the formation of soil layers.
The specialists’ practice of KFI shows that the following issues are often addressed:
- Is there a layer of soil (objects of soil and mineral origin) on the carrier object (it is indicated on what exactly)?
- Do comparable objects (layers on the carrier and soil from the place of event) have a common generic (group) affiliation?
- Are the data of layers (it is indicated which are) from a certain area of the place?
- What is the mechanism of formation of soil layers?
- What are the characteristics of the place from which the layers of soil occur on the carrier objects?
According to the “Instructions on the appointment and conduct of forensic expertise and expert studies” approved by the Ministry of Justice of Ukraine, the following rules should be observed in the preparation and designation of soil science expertise:
- when researching soil objects with the aim of establishing their origin from a certain section of the place, soil samples are sent for comparison from the place where the authority (s), which has appointed expertise (attracted expert), was a carrier object (the place of detection of a corpse, footprints of shoes, etc.), and other places within the place, is identified. In addition, control samples should be provided from adjacent places, similar to those that are different from that identified, for example from an adjacent field, with a different crop, from the place, which has a different vegetation profile, another profile, etc;
- sampling is conducted taking into account the characteristics of the place, which is identified;
- if the place has a relatively uniform surface, then four or five individual samples are taken from the surface layer of the place of contact of the carrier object with the soil and at least two control samples from adjacent areas (mixed with 4 to 5 samples selected within a radius of 2 to 5 m)
- samples are taken from the surface layer of the soil at a depth of not more than 5 cm with a mass of 100-150 g and packed in paper bags;
- if the place is a hollow (ravine, ditch, pit, etc.), samples are taken from the bottom and various genetic horizons of walls, slopes, and control – from the surface of the soil near the troughs and from adjacent areas of the place;
- all samples are air dried and placed in bags;
- on sampling, if there is such a need, you should consult an expert (specialist) or invite him/her to participate in this action;
- document on the appointment of an expertise (involvement an expert), a protocol should be added to inspect the scene of the incident with the outline plan. If the inspection of the carrier-bearing objects is formalized in a separate protocol, it is also attached. It is important that in the materials provided to the expert, soil sampling sites are identified. In addition, it is necessary to provide information on weather conditions and the nature of the use of objects with soil layers in the period from the time of the event to the time of sampling and the appointment of an expertise (involvement of an expert). If during this period works were carried out on the scene that could change the characteristics of the soil (digging, construction, cargo and other works, as a result of which extraneous impurities may remain on the soil), this should also be reported to the expert;
- each object on which soil layers are found is packaged separately. To the packages of samples, a tag with its number and the place of its withdrawal shall be affixed. The latest data should be coordinated with the plan-scheme of the scene.
Specialists of KFI help citizens solve problematic issues related to various kinds of expert studies. More detailed information on all types of research can be found in the section in expert activity.