From July 2020 through January 2021, HGL installed and operated a solar-powered air sparge system to remediate chlorinated volatile organic compounds in groundwater at Kennedy Space Center, Florida (Figures 1 and 2). The National Aeronautics and Space Administration (NASA) had selected an air sparging remedy to reduce contaminants in a “hot spot” area to concentrations that support transition into monitored natural attenuation. To address logistical challenges associated with connecting remediation equipment to a conventional electrical power source, HGL designed a more sustainable GSR-based system that used solar power to generate 100% of the energy required for its operation. The HGL-designed system significantly reduced both the cost and environmental impact associated with the remedial action by eliminating the need to construct and operate a system with supplied electricity. By using solar power, the logistical challenges of supplying outside electricity were solved, and the greenhouse gases that would have been generated during construction and operation were eliminated.
Further, during the construction of the solar-powered system, HGL installed aboveground rather than underground piping to eliminate the need to mobilize additional equipment to the site, reducing additional greenhouse gas and dust emissions. During construction permitting, the location of the proposed system was easily relocated to accommodate facility constraints without requiring significant design changes to accommodate the electrical connection.
The operation of the system exceeded project objectives and attained the more stringent Florida Department of Environmental Protection groundwater cleanup target levels within the air sparge treatment area. The project demonstrated to NASA the benefits of using solar-powered air sparge systems as a sustainable technology to address legacy groundwater contamination where electrical connections were a limiting factor while simultaneously reducing the environmental footprint of NASA’s remediation program.