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Draft Guidance for Silica Gel Cleanup in Washington State

Publication number Date Published
22-09-059September 2022
VIEW NOW Draft Guidance for Silica Gel Cleanup in Washington State (Number of pages: 19) (Publication Size: 932KB)
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Author(s) Charles San Juan
Description The guidance contains information about using Silica Gel Cleanup (SGC) when testing for diesel range organics in Total Petroleum Hydrocarbon (TPH) groundwater testing.
Silica Gel Cleanup (SGC) is a process where silica gel can be used in Total Petroleum Hydrocarbon analysis to adsorb the polar metabolites and remove or greatly reduce non-hydrocarbons from groundwater sample extracts. When using SGC, you should analyze groundwater samples both with and without applying SGC. The difference in the analytical results provides a measure of the diesel fuel biodegradation components, or polar metabolites.


Sept 2022 – Oct 2022: Received public comments. Currently under review and revision.

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Keywords Diesel Range Organics (DRO), groundwater sampling, Total Petroleum Hydrocarbons (TPH)., Total Petroleum Hydrocarbons (TPH) analysis, Silica Gel, weathered groundwater diesel-range organic plume, Silica Gel cleanup

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