The Testing Laboratory Directorate (TLD) is accredited to test various characteristics of samples of liquid waste, tailings, technological sludge, eluates from their leaching.
The tests performed for basic characterization and Conformity Assessment of waste are performed in accordance with the normative regulations of:

• Ordinance No 2 from July 23 2014 for waste classification;
• Ordinance No 6 from August 27 2013 for the conditions and requirements for the development and exploitation of depots and other facilities and installations for waste disposal and utilization. ;
• Ordinance for the specific requirements for the management of tailings;
• Order RD – 250/21.04.2015of the Ministry of Environment and Water of Bulgaria regarding sampling and testing of waste by components for classification purposes;
• Order RD – 950/13.12.2014 of the Ministry of Environment and Water of Bulgaria regarding testing methods, aimed at basic characterization and conformity establishment.

The testing of the characteristics in the tailings and eluates is performed with modern equipment: ICP-OES, ion chromatograph, RFA, GC, GC/MS and spectrometers.
The forms of sulfur are determined: Total sulfur – using high-temperature combustion, performed using a “Leco” apparatus and Sulphide Sulfur – combustion and titration method.
As additional parameters when performing basic characterization of waste, the acid neutralization potential, total carbon and loss on ignition are also determined.
For evaluation of the acid-reduction properties of waste, a standardized kinetic test is performed (a minimum of 20 weeks).
TLD also performs diagnostics of the mineral composition (qualitative and quantitative X-Ray Diffraction Analysis), granulometric characteristic (laser diffraction) and micro probe analysis; these activities are beyond TLD’s scope of accreditation.