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- Location: Western Colorado
A.5.0 HISTORY OF PRACTICES IN THE SAMPLING AND PREPARATION OF SOLID MATERIALS FOR VOC ANALYSIS
A.5.1 Traditional Practices
Over the past 20 years, solid samples obtained for VOC analysis were collected using a spatula -type device to completely fill a container for transfer off-site before the introduction of certain preparation steps and analysis within a 14-day holding time. VOC sampling procedures recommended the use of clean stainless steel utensils to completely fill either 40-mL to 250-mL glass containers. The containers were then closed with polytetrafluoroethylene (PTFE)-lined caps. Sample containers were stored in coolers at 4 ± 2E C and shipped to field or off-site support laboratories for subsampling (usually with 1 to 5 g aliquots) and subsequent analysis. The common holding time for these bulk soil samples, held at 4 ± 2EC, was 14 days.
A close reading of 5035 is nearly as restrictive as 5035A. Basically stating there is no way to have a 14-day hold time without either freezing or MeOH preservation.
Now we have vendors from out of state that insist that all samples be taken with TerraCore samplers into pre-weighed VOA's with 5-10mL of MeOH. Apparently, the only way to have a 14-day hold time, other than freezing all samples to <-7C and no less than -20C. See for example method 5035A Table A.1.
What has been the tradition in your states if you are doing 8260 VOC's on soils?