This practice is intended as a means for obtaining an extract from mine rock and soil samples measure cyanide concentrations. Cyanide is analyzed in mine rock and soil extracts for measurement of cyanide concentration; however, improper sample collection and extraction can result in significant positive or negative bias, potentially resulting in unnecessary permit violations or undetected cyanide releases into the environment.

This practice is designed to mobilize aqueous cyanides present in the solids, so that the resulting extract can be used to assess leachate that could potentially be produced from remediated mine rock or soil in the field.

This practice is not intended to simulate actual site leaching conditions.

This practice produces extracts that are amenable to the determination of minor (trace) constituents. When minor constituents are being determined, it is especially important that precautions be taken in sample preservation, storage and handling to avoid possible contamination of the extracts.

This practice uses a comparative test method and is intended for use as a routine method for monitoring remediated mine rock and soils after process releases and remediation. It is assumed that all who use this practice will be trained analysts capable of performing it skillfully and safely. It is expected that work will be performed in a properly equipped laboratory applying appropriate quality control practices such as those described in Guide D3856.