NAPL Compositional Changes Influence Partitioning Coefficients

• Published in: Environmental science & technology 1998-11, Vol.32 (22), p.3574-3578
• Main Authors: Lee, Cindy M, Meyers, Sarah L, Wright, Charles L, Coates, John T, Haskell, Patrick A, Falta, Ronald W
• Format: Article
• Language: English
• Subjects: Applied sciences; Bioremediation; Chemistry; Contamination; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Groundwaters; Natural water pollution; Pollution; Pollution, environment geology; Water pollution; Water treatment and pollution
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es980261x

Partitioning interwell tracer tests (PITTs) that were developed by the petroleum industry are being used to characterize the extent and amount of subsurface contamination by nonaqueous phase liquids (NAPLs). A promising application of PITTs is to estimate the volume of contamination removed by various remediation technologies by conducting the tests before and after remediation efforts. Laboratory experiments with a light NAPL from Hill Air Force Base, UT, the site of the SERDP demonstration of innovative technologies, indicate that the type of remediation technology used changes the partitioning of the tracer compounds between the NAPL and the aqueous phase. Partitioning coefficients (K nw) that were measured by static and dynamic methods showed a statistically significant change in value after the NAPL was treated in batchwise washes with a cosolvent that simulated enhanced dissolution. In contrast, the value of K nw showed little change before and after the NAPL was treated in a column with a cosolvent that simulated mobilization. The results indicate that PITTs could significantly underestimate the volume remaining of a complex NAPL like the Hill AFB material for an operation that employs the solubilization mechanism without a corrected K nw for the post-treatment test.