A dairy in Sanandaj, Iran, uses activated sludge treatment to clean up its wastewater. The study looked at how well this process worked in removing pollutants like BOD, COD, and TSS. The results showed that the treatment was good at removing TSS, but not as effective for BOD and COD. The levels of BOD and TSS in the treated water were below national standards, but COD was still a bit high. Overall, the activated sludge treatment did a decent job of cleaning up the wastewater, but there is room for improvement in removing certain pollutants.