Demonstration of MicroBlower™ technology for sustainable soil vapor extraction: Case studies at the Savannah River Site, South Carolina

Abstract

The MicroBlower Sustainable Soil Vapor Extraction System is a cost-effective device specifically designed for remediation of organic compounds in the vadose zone. The system is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction to natural attenuation. It can also be a better choice for remediating small source zones that are often found in "tight zones" that are controlled by diffusion rate. The MicroBlower was developed by the Savannah River National Laboratory at the US Department of Energy's Savannah River Site to address residual volatile organic compound (VOC) contamination after shutdown of active soil vapor extraction systems. In addition, the system has been deployed to control recalcitrant sources that are controlled by diffusion rates. O Braden H. Rambo is a senior field scientist at CRB Geological and Environmental Services, Inc., and he has worked in the environmental industry since 2004; for most of his career, he has studied and applied techniques for biodegradation of chlorinated solvents. He received a BS in geology and a minor in environmental engineering from Clemson University. During an internship at SRS, he assisted groundwater and vadose-zone remediation efforts. Rambo is pursuing an MBA through the University of Florida and plans to qualify as a professional geologist within the year.

Vapor Extraction Well Performance and Recommendations for Transitioning to Passive Extraction at the Former DUS-II Site

“…These observations were reported for vapor extraction wells associated with the former 782-5M SVEU that was located just north of the MASB along the abandoned process sewer line. In contrast, it was recently reported that 24-volt Microblowers have a radius of influence of 41 feet when operating at 10.3 scfm (Noonkester et al, 2012a). The later investigation was performed between the 782-5M SVEU and the WSTS location.…”

“…The majority of these wells are located in Parcel 2 with VEW-15A located in Parcel 3, VEW-23F located in Parcel 4, and VEW-34F located in Parcel 1. In comparison to other MicroBlower™ deployments (Noonkester et al, 2012a) these wells have larger diameters (4 and 6-in) and have screen lengths ranging from 30 to 120 feet. These parameters couple to create large well bore volumes that facilitate the use of the highest capacity systems available.…”

“…This utilizes earlier observations on the performance of these systems within A/M Area (Noonkester et al, 2012a).…”

“…The 24-volt version of the MicroBlower is designed to operate 24 hours a day and is capable of generating a maximum vacuum of 10 inches of water and a maximum flow rate of 18 scfm (Noonkester et al, 2012a). The actual performance will vary depending upon the pressure and flow characteristics of each well; a reasonable performance of 10 cfm should be expected from these wells.…”

Vapor Extraction Well Performance and Recommendations for Future Soil Vapor Extraction Activities at the A-014 Outfall

“…Wells that are identified as candidates for transition to low energy operation are further analyzed and estimates of performance under MicroBlower™ extraction are performed. This utilizes earlier observations on the performance of these systems within A/M Area (Noonkester et al, 2012a).…”