Shapar A.G.

There are many hundreds tons of useless and forbidden to application pesticides, accumulated in the different aggregate state on the territory of steppe Ukraine. Most pesticide storages are not guarded and do not have sanitary-hygienic passports. Pesticides are not protected from the climate factors influence (fallouts, temperature and wind actions). Such uncontrolled storage conditions cause pesticides to be leaked into soils, washed off by precipitation water, gotten in the water-supply sources. The most widespread method of soils cleaning from the contaminants (including pesticides) includes its complete mining and removal for further cleaning in special areas or storage within special sites. As a rule, these methods are very expensive and they cause heavy industrial influence on territory such as influence of long distances transportation and related high risk of industrial failures and catastrophes. The important task is to develop and state new technology of pollutants removal from soils and underlying material.

The technology of soils and bedrock cleaning from different pollutants is realized in the EU project CLEANSOIL – AN INNOVATIVE METHOD FOR THE ON-SITE REMEDIATION OF POLLUTED SOIL UNDER EXISTING INFRASTRUCTURES (the participants: Verein zur Forderung des Technologie Transfers an der Hochschule Bremerhaven e.V., Germany; Bioazul S.L., Spain; M.V. Lomonosov Moscow State University, Russian Federation; Globe Water AB, Sweden; Ugra State University, Russian Federation; Institute for Nature Management Problems and Ecology of National Academy of Science of Ukraine, Ukraine; Politechnika Warszawska – Warsaw University of Technology, Poland; Institute for the industrial Ecology of the North, Russian Federation). It is based on horizontally directed well-drilling technology application. The bore holes are afterwards equipped with the system of fabric sleeves capacities filled with some adsorption substance. The method includes the installation systems of horizontal mining holes within the borders of contaminated territory, on a certain depth, with the subsequent adsorption capacities inserted. When pollutants are adsorbed from soil at the required level, after certain period of time, the system is removed, and adsorption material is regenerated for repeated use.

According to the project the area site of project CLEANSOIL soil remediation is organized on distance of 2, 5-3, 0 km on the South from Dnipropetrovs’k by the Novoaleksandrovka village. The site is collocated with storage of pesticides forbidden and useless for application. There are a lot of chemicals, which were stored in embankments, sacks and metallic barrels for many years. Containers and chemicals were breaking apart in time; chemicals and fertilizers were mixed and entered into the reactions. It is impossible to determine the content of changed and transformed soil chemicals. It is only possible to state that during the storage work there could be kept varied mineral fertilizers and pesticides such as nitrogen, Granozan (a phenyl-mercury acetate), TMTD (С6H12N2S4), Agronal, Radosan, Prometholonum, poly-chlorpynen, poly-chlorkomfen, and other Persistent Organic Pollutants. Pesticide pollution of soils in the district of pesticide storage can substantially worsen the ecological situation at Novoalexanrovka village. In particular, toxic substances accumulation actually achieves numbers exceeding 1000 maximum possible pesticides concentrations. Taking into account character and degree of soil contamination by pesticides the required degree of their purification was determined for the aims of the examined project. The preservation of the soil fertility is not the aim of the project due to the need absence to use the soils located under the storage building and surrounding territory for the agricultural production. Achievement of cleaning level equal to 0,01 of initial, though still great comparing to the values of maximum-possible concentrations, but will allow to catch project objectives and substantially reduce the level of contamination.

Hydro-geological conditions in the research site area are characterized by the deep horizon of groundwater (5-7 m) that in a complex with the insufficient precipitation black-soil moisturizing creates certain problems for practical realization of project CLEANSOIL. Therefore at development of experimental site organization project both these features and the pesticide soil contamination features were taken into account. Research site consists of two areas. Horizontally directed mining holes were drilled under the pesticide storage building on the first area. The trajectory of bore drilling is adopted so that the horizontal areas of mining holes were on a depth of 1,5-2,0 m from the surface and are affected by the most polluted soils and parent material on the depth. On the second area traditional ground trenches were set. After digging perforated polyethylene pipes with fabric sleeves capacities filled with adsorption material were placed inside and filled up with polluted soil on the top. Besides a few bore holes were drilled by horizontally directed drilling method as well. This research area was established to explore and estimate polluted soils soakage rate in order to determine the effective cleaning technology in the arid conditions (little amount of precipitation), which are present at the experimental site.

The preliminary results of our experimental researches in 2007 testify that the offered technology of soil clearing (project CLEANSOIL) provides extraction of pesticides from ordinary chernozem of Dnipropetrovs’k region. The results of the experiment were estimated on reduction of the degree of soil pollution after washing. The basic attention was given water soluble pesticides (simazin, atrazin, prometrin). After washing the pesticide contents in superficial humus horizon has decreased up to 0,001-0,335 mg/kg. But the pesticide contents in similar horizon (in the soil only under action of atmospheric precipitation) has authentically decreased only on 30 % and remained very high – 1,629 mg/kg. The tests adsorbent were investigated. It absorbs significant amounts of pesticides, which move downwards with filtration of waters. For example the simazin contents in adsorbent reaches – 1,112-1,288 mg/kg.