188 Bulletin UASVM, Veterinary Medicine 65(1)/2008 pISSN 1843-5270; eISSN 1843-5378 COMPARATIVE STUDY OF SURFACE WATERS POLLUTION BY SLAUGHTERHOUSES WASTEWATER Borda C., Silvana Popescu, Daniela Rodica Borda University of Agricultural Sciences and Veterinary Medicine, Faculty of Veterinary Medicine, 3-5 Manastur St., Cluj-Napoca, Romania, e-mail: cborda@usamvcluj.ro Keywords: surface water; wastewater; slaughterhouse; polluting; comparison. Abstract: one of the pollution sources for the surface waters is represented by slaughterhouses wastewater. This study; performed at two such units; showed that wastewater treatment was insufficient; even if one of these slaughterhouse was provided with a modern wastewater treatment plant. Analyses of water samples collected from the region of the outflow into surface waters showed exceedings of the admissible limits for total suspensions; pH and ammonium. Exceedings were more important in the higher capacity slaughterhouse; leading to a more significant pollution potential. INTRODUCTION Wastewaters from slaughterhouses have a high pollution potential (Finnish Environment Institute; 2002; Masse and Masse; 2000; Paszkiewicz; 1999). This potential acts; depending on the outflow place; on the sewage networks (Borda et al.; 2002) or on the surface waters (Borda et al.; 2005). Even if the number of slaughterhouses has been considerably decreased comparatively to the 90’s situation; there are still enough of such units evacuating important quantities of wastewaters (Borda; 2007). This paper presents a comparative study between two slaughterhouses; regardind the effect of outflowed wastewaters on surface waters. MATERIAL AND METHODS Research was performed at two units; A and B. Slaughterhouse A; situated in Cluj county; slaughtered a mean number of 25 cows and 120 pigs/month. Wastewater treatment was provided in a settling tank with three compartments; wherefrom the water was evacuated into a rivulet. Slaughterhouse B; situated in Alba county; was meant for poultry slaughtering; with a maximal capacity of 24000 tones/year. Wastewater; once treated in a modern mechanical-biological treatment plant; was also evacuated into a rivulet. Three water samples have been collected for each of the slaughterhouses; from the region of outflowing into the surface waters. Samples have been analysed in the Hygiene and Environmental Protection Laboratory from the Faculty of Veterinary Medicine Cluj-Napoca and in the laboratory of „Romanian Waters” National Administration; Some-Tisa Waters Department Cluj-Napoca. The next parameters have been determined: - total suspensions: centrifugation method; - conductivity: with electronic conductivity-meter (Conmet 1; Hanna Instr.); - pH: with electronic pH-meter (Checker 1; Hanna Instr.); - dry matter: at 105 o C; after centrifugation; brought to you by CORE View metadata, citation and similar papers at core.ac.uk