Beneficial Reuse of Wastewater
You've heard the old saying, "When life gives you lemons, make lemonade?" Well, we share that philosophy, but we aren't making lemonade! Dalton Utilities has an ongoing partnership with Harvest Farms to take the solids (or sludge) from our wastewater system and put it to work to improve the environment.
In the wastewater treatment process, solids (or sludge) are pulled from the wastewater in several of the treatment stages. These solids ultimately are sent to our sludge handling facility where a polymer or "caking" agent is added. The mixture is then sent through a high-speed centrifuge to remove any remaining moisture.
At this point, the sludge is mixed with organic material, like tree bark and wood chips. The mixture is composted in large containers where it must be kept above 131 degrees Fahrenheit for three consecutive days and an average of 114 degrees Fahrenheit for a total of 14 days. No special heating is required as the composting process produces its own heat. During this heating process, any pathogens in the sludge/organic material are eliminated. The compost is then placed in windrows (long rows of heaped compost in an open field) on our Land Application System facility to complete the decay process for an additional four to six months.
Is it safe? The composting process is closely regulated by the Georgia Environmental Protection Division (EPD) to ensure the safety of the product. According to Gerry Harstine, president of Harvest Farms, "All soil is made up of things that have decayed, but the end product of composted sludge is safer and cleaner than the soil you might dig up in your front yard."