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Title: Possible replacements for the biochemical oxygen demand (BOD) test and suspended solids as measures of effluent and water quality : interim report (402/6/HO)
Author: K. Clark
Author: S. Comber
Author: A.M. Gunn
Document Type: Monograph
This report covers progress on R and D Project 402 for the period December 1992 to March 1993, assessing possible replacements for biochemical oxygen demand (BOD) and suspended solids as measures of effluent and water quality. A limited assessment of archive data for sewage treatment works effluents has revealed a good correlation between BOD and COD, with little evidence of site-specificity. A much poorer relationship existed between BOD and TOC, but this may have been influenced by poor solids handling capability of the TOC instrument employed in the study. A more comprehensive NRA laboratory evaluation of possible alternative determinands has now been initiated. This covers a range of rivers, sewage effluents and industrial effluents. TOC data are being obtained using four different instruments, two with good solids handling capability. Other determinands include BOD, COD, ammonia, suspended solids and turbidity. An assessment of the likely impact of a move away from BOD and suspended solids on water quality models has been undertaken. In some respects, there would be advantages here in changing from BOD to a more direct chemical measure of available organic carbon. However, any such change would inevitably have considerable cost implications in terms of redesign and recoding of models. The same would also hold for a change from suspended solids to turbidity measurements.
Publisher: National Rivers Authority
Publication Date: Bristol
Publication Place: 1993
Extent: 25
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