recycled slurry 24 is delivered to overspray headers 20 rather than being split between over and under spray headers this enables more of slurry 24 to be provided to the top of tray 18 where contaminant removal efficiency is greater as a result of contact both in the spray and the resultant froth on tray or grid 18 finally awning 32 directs the incoming flue gas 16 initially downward providing a downward swirl effect that intimately mixes the gas 16 and slurry 24 from tests conducted on such a system it has been shown that the availability and reliability of wet fgd systems without underspray headers is the same as those with such headers such data also shows that the performance or contaminant removal of such systems can be maintained by properly selecting the spray flow characteristics above tray 18 additionally there has been no increase or build up of solids underneath tray 18 the slurry flow falling from compartments 44 on awning 32 also provides for the quenching and humidifying of flue gas 16 and for even gas distribution within tower 10 any side to side flow of flue gas 16 passing through the liquid curtain formed from the flow of slurry 24 from overspray headers 20 above will be reduced and or eliminated side plates 46 of awning 32 provide resistance to correct any such side to side movement alternatively this improvement can also apply to grid or packed fgd systems that have sufficient liquid with adequate flow distribution above the packing or grid also this improvement can apply to any absorption or quench system that incorporates a tray or gas distribution device with an overspray above this includes aqueous scrubbers for such gaseous pollutants as hcl hf no x so 2.