Sewage dump is the main organic waste component accumulating in water treatment companies, and therefore the utilization of dump remains a burning issue. Fertilization is the most popular and cheapest way of using sewage dump a part of which is intended for agriculture in most European countries for composting purposes. Sewage dump or its compost are suitable for fertilizing the upper layers of the soil in cases the concentration of heavy metals is not greater than sanitarian standards can tolerate. The examinations were carried out using different waste dump rates from Vilnius water treatment facility in willow (Salix viminalis) grown cultivated fields.
The analysis of the soil was executed after one and two years following the fertilization process. The obtained results indicate that waste dump is a valuable organic fertilizer which contains small amounts of heavy metals. Separate heavy metals migrate from sewage sludge compost to plants differently. It was noted that the concentration of heavy metals in willows was greater (except for Pb and Cd) than that in the soil.

Article in Lithuanian