Paper Title
The Water Quality exiting the Arad Sewage Treatment Plant

Abstract
The discharge of insufficiently purified effluents led to the alteration of the quality of water courses and the appearance of a wide range of pollutants: organic and microbiological substances. The degree of water pollution, discharged directly into the effluent can lead to an imbalance of the ecosystems and its monitoring is necessary to avoid destruction in the food chain. In the assessment of water pollution, sudden increases in the values of organic matter are particularly significant, which raises the intervention of a pollution. The organic substances in water are determined by the oxidation of organic matter with oxidants such as potassium permanganate and potassium bichromate by measuring BOD5 and COD, respectively. The paper presents the efficiency of the biological treatment process of a sewage treatment plant by monitoring of waste water through the BOD5 and COD values. The exit values are bellow the allowable limits given in NTPA 001/2002 and NTPA 002/2002. Keywords - Sewage Treatment Plant, BOD5, COD, Potassium Permanganate and Potassium Bichromate