It sprays out as pure water just like the municipal sewer systems. Essentially, those of us on aerobic systems are a municipal sewer system of one. I have two pop-up sprinklers that water my grass. As long as the air pump works to keep the little bacteria bugs happy and well fed, there is no odor at all in the spray except for a slight chlorine smell from the tiny bit of "insurance" chlorine added to the water. The nice thing about aerobic is no leach field problems. The bad thing is the state requires an annual service contract, so it costs me about $225 annually or about $75 per inspection and cleaning every 4 months. My aerator motor runs continually and that is an electric expense just like my well pump. The motors last about 6 to 8 years and have to be replaced because of shot bearings, cost: $400. My initial cost for the system was $5500 back in 2001. I also had to pay an engineer to approve the layout and $400 to the county for an inspection of the installation.