How do I meet the holding times for hexavalent Chromium (Cr+6) in water samples?
The normal holding time for hexavalent chromium in water samples is 24 hours. The holding time can be increased to 30 days if the water sample is preserved with sodium hydroxide. How much time do I have to get my samples to the laboratory? It is recommended that samplers ship samples to the laboratory on the same day that they are collected, or as soon as possible thereafter. Note that some analytical parameters have very short holding times (See the analytical method for maximum holding time). Holding times are the maximum lengths of time that samples may be held from time of collection to time of preparation and/or analysis in the laboratory and still be considered valid. Why does IDEM need to see all the QA/QC data? The analytical methods require certain quality control samples and tests to document the precision and accuracy of each analysis. Each element in a complete QA/QC program is designed to give a specific piece of information about the results. There are many different item
