The article describes the hydrogeological conditions occurring very deep deposits of brown coal “Złoczew”, its place in the tectonic trench. Attention is drawn to the numerous faults, which caused quite a strong differentiation of the ceiling and floor deposits. The deposit is situated in the surroundings of the Upper Jurassic limestones, also heavily involved tectonic and places with developed karst phenomena. The nature of the geological structure, location of deposits and around tracks with very good local groundwater flow conditions indicate the necessity to choose slightly different drainage system than previously used in the pit, “Bełchatów” and “Szczerców”. At the same time the depth of the deposit and its strong hydration raises the question whether and under what conditions its operation would be economically justified.