Long-Term Effectiveness of Isolation Techniques for Contaminated Soils

Abstract

Seven different isolation methods, designed to prevent the migration of pollutants away from contaminated disposal sites, are compared. A 17-step integrated risk methodology is developed to compare these isolation methods. A disposal site containing heavy metals and toxic organics is used as a case study. Model calculations based on actual data predict that the Maximum Tolerable Concentration (MTC) for drinking water is never exceeded, while the MTC-lead is exceeded for the reuse of contaminated land for housing by all isolation methods after 100 years. Isolation methods are generally effective for the first 10 years, then have a retarding effect after 25 years, but are generally similar to a "non-intervention" reference situation after 100 years. Thus, it is argued that the current types of isolation techniques in use represent a potential "time bomb".