The potential of covering the manure tanks have been confirmed and reductions of at least 90% seem to be feasible. The covers have to be sealed properly to prevent leakage and venting of the gases emitted (ammonia, H2S) could be treated trap and recycled through a scrubber. More work is needed to understand the pH changes occurring when the tank is covered as compared to uncovered as pH has an important role in ammonia release also changes in the methane measurements has also to be done as the method used was too insensitive.