On January 11th, 2011 The Nevada Division of Environmental Protection, Bureau of Mining Regulation and Reclamation (BMRR) issued a statement clarifying the acceptable methods for the analysis of Weak Acid Dissociable, or “WAD”, cyanide. The statement listed two acceptable methods: ASTM D2036-082 and SM 4500CN I.
Keep in mind this concerns only compliance monitoring samples that are being reported to BMRR. The issued statement doesn’t cover any sample that is not for compliance, or is being reported to any other agency.
Both acceptable methods are manual distillation methods that use a weak acid (glacial acetic acid) to break up easily dissociated cyanide complexes, capture the free cyanide in solution, and then analyze the solution using a few different techniques. These two methods have long been thought to be the most reliable techniques for the quantification of cyanide in waters. BMRR stated that only data obtained using one of these two methods would be acceptable for compliance monitoring.
Western Environmental Testing Laboratory (WETLAB) has been using SM4500CN I for the analysis of WAD cyanide for many years and is currently certified by the State of Nevada, Bureau of Water Quality Planning. Just like any method or technique that WETLAB wishes to use for compliance monitoring sample analysis, we have gone through a rigorous certification program that includes an on-site audit and the analysis of “blind” QC samples.
Over the last decade new techniques have been developed for the analysis of the easily dissociated cyanide complexes that WETLAB hopes become acceptable for BMRR reporting. One specific method is known as Flow Injection Ligand Exchange or F.I.L.E. cyanide. WETLAB is already certified and equipped to use this more efficient and environmentally sound testing method, which would provide clients with quicker turn-around time for results. Should BMRR choose to accept data generated from this technique, WETLAB will contact clients to inform them of our wish to change methodologies.
As always, if you have any questions regarding the information contained in this blog, don’t hesitate to call (775) 355-0202.