Multi-Site In Situ Air Sparging, Multiple Locations

Site Name:

Multiple (10) Sites - Air Sparging

Location:

Various

Period of
Operation:

Varied by site

Cleanup
Type:

Field demonstration and full scale

Technology:
Air Sparging
- Total of 10 projects - systems included 6 sites with in situ air sparging and 4 sites with in situ air sparging/SVE; both full-scale and demonstration-scale projects
- Sampling and monitoring procedures varied depending on site conditions and system configuration; included soil gas testing, vapor sampling, groundwater sampling, air flow and air injection pressure monitoring, and helium tracers

Cleanup Authority:
Not provided

Contacts:

Lt.Col. Tim Wiley
Air Force Project Manager
AFRL/MLQE
139 Barnes Drive, Suite 2
Tyndall AFR, FL 32403
Telephone: (850) 283-6199
Fax: (850) 283-6064
E-mail: timothy.wiley@tyndall.af.mil
Dr. Andrea Leeson
Battelle Project Manager
Battelle Memorial Institute
505 King Avenue
Columbus, OH 43201
Telephone: (614) 424-5942
Fax: (614) 424-3667
E-mail: leeson@battelle.org

Contaminants:
Volatile and Semi-volatile organics and PAHs
- Variety of contaminants at the sites including BTEX, anthracene, napthalene, MTBE, TCE, DCE, VC, benzene, TPH, and PCE

Waste Source:
Varied by site, including waste disposal in landfills, leaks from fuel and POL storage, and firefighter training areas

Type/Quantity of Media Treated:
Soil and Groundwater
- Quantity treated varied by site

Purpose/Significance of Application:
Multi-site study of in situ air sparging to evaluate the Air Sparging Design Paradigm

Regulatory Requirements/Cleanup Goals:
- The objective of the study included determining whether the Air Sparging Design Paradigm was effective and valid based on data collected during the study

Results:
- The data supported the necessity to use a suite of diagnostic tests in designing and installing air sparging systems rather than relying on one type of testing; such diagnostic tests included pressure response testing, deep vadose zone helium tracer testing, and dissolved oxygen monitoring
- The data indicated that the 15-ft well spacing prescribed in the design paradigm would have been sufficient to achieve adequate treatment of the target zone
- Many of the air sparging systems in the study were poorly instrumented and monitored to the extent that system performance was compromised

Cost Factors:
- Costs for the demonstration air sparging system at Port Hueneme, CA was $189,880 or $130 per cubic yard, based on 1,500 cubic yards of soil treated
- Projected full-scale costs for this system were $268,490 or $179 per cubic yard based on 1,500 cubic yards of soil treated

Description:
In the mid-1990s, the U.S. Air Force Research Laboratory, Airbase and Environmental Technology Division, Tyndall AFB, initiated an air sparging project, funded by AFRL/MLQE, SERDP, and U.S. NFSEC. A key goal of the project has been the development of a technically defensible and praticable Air Sparging Design Paradigm. This paradigm was evaluated based on information at 10 sites to determine whether it was effective at evaluating air distribution and to use the results to modify the paradigm.

The 10 sites selected for the study included sites with air sparging systems in place that were being used to treat various soil types and various contaminants. The results of the study showed that many aspects of the Air Sparging Design Paradigm were effective, with the results of the study used to develop the final Air Sparging Design Paradigm.