Physicla barriers constructed in acontaminated groundwater systemthat intercept and degrade or remove soluble pollutants yet allowgroundwater to flow through are called permeable barriers. They maybe constructed as trenches placed down gradient from a leak or spill,and the trench backfilled with media which intercepts the solutes andremoves them from solution. This project investigated the feasibilityof using trench based air stripping to remove volatile hydrocarbonsfrom groundwater contaminated with gasoline components, specificallymethyl tertiary-butyl ether (MTBE). Based on theoretical calculationsand previous laboratory research a 9 m long trench-based airstripping/biodegradiation barrier was constructed at a sitecontaminated from a leaking underground gasoline storage tank.Monitoring data show the trench removed approximately 100/100 of theMTBE reaching it by natural groundwater flow, event at a relativelylow air-to-liquid flow ratio. The total construction cost of thebarrier was less than $5000, including the installation of amonitoring well, and annual operating costs were found to be about $180/year. Guidelines for successful application of the permeablebarrier concept to groundwater remediation are presented based on theexperience from this project.
展开▼
