Measuring Groundwater and Contaminant Flux: Passive Flux Meter Field Applications and Issues with Alcohol Degradability

The passive flux meter (PFM) developed at the University of Florida is an innovative device that is inserted into a well in order to measure groundwater and contaminant flux. The in-situ device consists of an activated carbon matrix impregnated with known amounts of alcohols that are desorbed at rates proportional to the groundwater flux through the device. After exposure the sorbent is extracted to quantify the contaminant mass intercepted and the resident alcohol mass remaining. Since the alcohols employed in bioactive sites are degradable, studies were conducted to investigate biodegradation issues and microbial acclimation times in field application. Also, silver-impregnated activated carbon was compared to unamended activated carbon in batch and column studies to determine silver ion effects on degradation. The studies confirm degradation and microbial acclimation occurrence, and demonstrate that silver impregnated activated carbon does inhibit degradation. Issues remain with biofilm/biofouling observed in the field as well as column studies.