Method verification of chemical oxygen demand (COD) and total suspended solid (TSS) analysis from Mentaya River

Research has been conducted which were intended to study the feasibility of the method and the quality of Mentaya River water based on chemical oxygen demand (COD) and total solid suspended (TSS) parameters. The method used in this research was based on SNI 6989.73-2009 with the titrimetric for COD analysis and SNI 06-6989.3-2004 using the gravimetric for TSS analysis. The results of verification analysis for precision tests determine COD and TSS by 3.3% and 1.2%, respectively. Approval values for determining COD and TSS were 102% and 97.4%, respectively. Estimated values for COD and TSS from certified reference material (CRM) were 49.33 ± 0.1356 mg/L and 73.6 ± 0.3916 mg/L respectively. The COD results of the Mentaya River at Samuda, Ketapang and Kuayan sections were 34 mg/L, 123.2 mg/L and 8 mg/L respectively. Meanwhile, the TSS results at Samuda, Ketapang, and Kuayan locations were 98 mg/L, 10 mg/L and 32 mg/L respectively. The results of the verification method can be concluded that the method for determining COD and TSS meets the requirements so it can be used regularly in the laboratory. From the COD analysis, the quality of the Mentaya River at the Kuayan section below the quality standard of Indonesian Government Rules No 82 of 2001, while the Samuda and Ketapang sections exceeded the quality standard. The analysis result for TSS of the Mentaya river at Kuayan and Ketapang sections was below the quality standard and the Samuda section exceeded the quality standard of Indonesian Government Rules No 82 of 2001.