Grain Size Analysis Results from Field Samples near Hinkley, California

Grain size analysis using an Advantech Sonic Sifter Separator was conducted as part of a study examining the occurrence of chromium and natural and anthropogenic hexavalent Chromium, Cr(VI) in groundwater. Data will be used to estimate naturally-occurring background Cr(VI) concentrations upgradient, near the plume margins, and downgradient from a mapped Cr(VI) contamination plume near Hinkley, CA (Izbicki and Groover, 2016).
Following field collection the samples were sieved into the greater than and less than 2 millimeter size fractions. The less than 2 millimeter fraction was sifted into seven grain size ranges. Each size fraction was weighed to 0.1 grams and photo documented. The cooperator for this study is the Lahontan Regional Water Quality Control Board.