A new method of manure storage, based on application of a denitrification bed isolated from the ground, was developed. The essence of the method lies in the fact that manure is stored in a landfill, which is a soil and sawdust mixture placed in a geomembrane lined excavation. Research has been carried out to check the effectiveness of this method in the aspect of preventing pollutants penetration into groundwater. Based on the results, it was found: ‒ large increase in ammonia nitrogen and potassium concentration, which indicates that these components were retained and did not penetrate into groundwater; ‒ after the growth period concentration of nitrate nitrogen was reduced, which should be associated with the ongoing denitrification process (nitrates were transformed into nitrogen gas as a result of the action of denitrification bacteria). The obtained results suggest that the denitrifying bed isolated from the ground protects groundwater against contaminants migrating in the effluents from the manure heap.