Abstract |
The overall objective of the project was to develop a technical base for decisions on the use of chemical countermeasures at releases of hazardous substances. Work included a literature search to determine the nature and quantities of contaminants at Superfund sites and the applicability of existing technology to in situ treatment of contaminated soils. Laboratory studies were conducted to develop an improved in situ treatment methodology and were designed to determine whether significant enhancement to the efficiency of water washing could be obtained by adding aqueous surfactants to recharge water used in a continuous recycle. The use of aqueous nonionic surfactants for cleaning soil spiked with PCBs, petroleum hydrocarbons, and chlorophenol was developed through shaker table and soil column tests. Based upon project results, the aqueous surfactant countermeasure is potentially useful for in situ cleanup of hydrophobic and slightly hydrophilic organic contaminants in soil, and should be further developed on a larger scale at a small contaminated site under carefully controlled conditions. However, reuse of the surfactant is essential for cost-effective field application. Accordingly, any future work should investigate the use of other surfactants that may be more amenable to separation. |