380748 Self Sustaining Treatment for Active Remediation (STAR): Design and Implementation at a Coal-Tar Impacted Site
Background: Self-sustaining Treatment for Active Remediation (STAR) is a novel and patented technology based on the principles of smoldering combustion, where the contaminants are the source of fuel. This new treatment method allows for in-situ treatment of recalcitrant organic compounds (coal tar residuals, heavy hydrocarbons etc.)using a network of locally installed treatment points, requiring minimal energy inputs. The most commonly applied treatment alternative would be to dig and haul the contaminated soil for ex-situ thermal destruction and permitted disposal of treated fill. This alternative represents significant energy inputs, logistical challenges, and results in high overall costs for site remediation. Because the STAR treatment uses the energy content of the contaminants themselves to effect the treatment, and cleans contaminated soils in place, this process represents a sustainable alternative to conventional treatment methods. The carbon footprint of the remedial design has been estimated to be 1/10th of competing alternative remedial options for the Site. This presentation will provide a summary of the full-scale design and implementation ofSTAR at a former coal tar processing site in Newark, New Jersey , and early results of the full-scale application of the STAR technology.
Approach: A CSM was developed utilizing hisSTAR at a former creosote manufacturing facility in Newark, New Jerseytorical data, and a combination of traditional and high resolution characterization methods. Three phases of pilot testing have been conducted at the site to verify treatment effectiveness and develop full scale deployment methods. These pilot tests were conducted to evaluate key design parameters such as: 1) contaminant mass destruction rates; 2) treatment radius of influence (ROI); and, 3) vapor emissions levels. These data were integrated into the design of a full-scale STAR treatment system for the site, with operations commencing in 2014 and continuing through mid-2016.
Results: The conceptual site model identified zones of impacted volume amenable to STAR treatment. Pilot testing has demonstrated sustained coal tar hydrocarbon destruction rates in excess of 800 kg/day supported through air injection at a single well. Deep treatment testing (twenty-five feet below the water table) resulted in the treatment of a targeted six-foot layer of impacted fine sands to a radial distance of approximately twelve feet. These results (and additional parameters) were used to develop a full-scale STAR design consisting of approximately 1800 specific treatment locations and a number of customized unit operations to remediate an approximately 14-acre footprint of contaminated soils within the project timelines (i.e., by mid-2016). Field activities began in early 2014 and progress is currently on-schedule.