In order to work out a procedure of diminishing the amount of heavy metals, barium and strontium in wastes, laboratory wastes were collected and investigated. The analysis revealed that mercury and silver are present only in the precipitate, as well as about 213 amount of lead, bismuth and cobalt. Other elements occur mainly in solution. It was also found that there was no justification for the separate segregation of particular analytical groups of elements, especially in the cases where it is difficult to enforce requirement of collecting wastes in proper containers. Solid wastes were divided into two groups: I - containing mercury and 2 - without mercury content. Metals were eliminated in the form of sulphides and hydroxides by their precipitation with sodium sulphide, flocculation, sedimentation and dehydration. Solutions left after metals separation meet requirements for wastes, which can be disposed of the sewage system.

The total content of lead in soil from the battery plant site was determined and a speciation analysis of this element was carried out using Rudd's method of sequential extraction. It was found out that lead is present in soil samples mostly in a low mobility organically bound form, which under certain conditions can, however, be absorbed by plants, and in a moderately mobile carbonate form. Lead was extracted from soil using sodium salt of ethylenediaminetetraacetic acid and sodium hydroxide solution and tests were also conducted to separate it from leaching solutions electrochemically. Extraction with Na2 -EDTA solution makes it possible to remove 86% of lead from soil, but the solution shows much lower lead extraction power when used for renewed leaching after having been electrochemically freed of lead. Extraction with NaOH solution gives worse results, namely only 70% of lead can be removed from soil, but the solution after having been electrochemically freed of Pb shows higher Pb leaching power when used for renewed leaching than in the case of Na2 - EDTA solution.

A procedure has been proposed for proceeding with homogeneous chemicals being technical products or reagents stored in unlabelled packages, in order to classify these substances to particular categories of wastes. A series of simple tests belonging to a classical analysis of chemical compounds, complemented with instrumental methods in needed cases has been proposed. The requirements have been established for equipment and necessary qualification of personnel in a laboratory in which identification is to be carried out. Attention has been drawn to risk accompanying this procedure and necessary precautions, which should be undertaken, especially due to possible explosive, inflammable and toxic properties of these substances. The worked out procedure was verified in tests and applied during cleaning the central chemical storage rooms.