This paper presents the results of an energetic potential analysis of coal slurries deposited in impoundments. Results shown are on an “as received” basis and for concentrates after beneficiation. Coal slurries were beneficiated using the following techniques: hydrocyclone classifier-separator, centrifugal separator, Reichert spiral separator LD4, and flotation. An assessment of energetic potential was made for concentrate, whereas losses of energetic potential due to beneficiation were estimated. Performed tests showed that the most effective method was flotation, where the loss of energetic potential was, on average, 15% and varied from 3 to 31% depending on the impoundment. The average value for the obtained concentrate was 25,057 kJ/kg, being the highest among all of the methods. The highest losses of energetic potential of coal slurries were observed in the case of the centrifugal separator with sludge removal of feed. The loss of energetic potential was on average 68% and varied depending on the impoundment from 13% to as much as 98%. Average calorific value was 22,864 kJ/kg. The results are similar to those obtained with the use of the Reichert spiral with initial sludge removal from the feed. The average loss of energetic potential of coal slurries beneficiated in Reichert spirals was 64%, and the calorific value 22,678 kJ/kg. The lowest calorific values of concentrate were obtained from the hydrocyclone classifier-separator. Despite a significant loss of energetic potential of coal slurries, which was on average 44% and ranged from 12 % to 97%, the calorific value of the product was 16,950 kJ/kg and did not increase significantly in relation to the calorific value of raw coal slurry, which was 16,427 kJ/kg. Results obtained from this research showed that it is possible to beneficiate coal slurries deposited at old impoundments. Nevertheless, they revealed that a high loss of energetic potential should be taken into account when applying certain technology.