Wastewater

Cyanide in NPDES Wastewater Samples

A common practice for cyanide extraction in soil and sediment is acid distillation. This approach is valid for all cyanide forms except the double metal cyanide complexes that are most likely to be present. The quality control practice of spiking a soil sample with simple cyanides, or strong metal-cyanide complexes, to validate acid distillation is misleading because these cyanide complexes are readily soluble. Acid distillation of cyanide in soil results in low and irreproducible recoveries for the double metal cyanide complexes most likely to be present. Acid distillation of cyanide in soil is ineffective and does not accurately measure total cyanide, nor does it estimate cyanide toxicity.

Learn more about the extraction and analysis of cyanide in soil and sediment samples
 

Ensuring Water Quality with Accurate TOC Analysis

The Biological Oxygen Demand (BOD) test measures oxygen consumed by the decomposition of organic matter in secondary wastewater treatment processes. Total Organic Carbon (TOC) analysis provides a direct quantitative measurement of organic contamination in wastewater, whereas BOD tests provide an indirect, empirical estimation of organic contamination.  Read A Comparative Study of Online and Laboratory TOC Analyzers for Analysis of Municipal Wastewater for a more detailed look at substituting TOC analysis for BOD monitoring.