The effect of heterogeneity correlation scale (& / #61548 / ) of hydraulic conductivity (K), equilibrium distribution coefficient (Kd) and mass transfer rate (& / #61537 / ) on the design and cost of the P& / T remediation system for different heterogeneity levels (defined by the variance (& / #963 / 2lnK)) and parameter distributions under the rate-limited sorption conditions was evaluated in this study. In addition, the impacts of initial amount of contaminant mass and plume configuration on the remediation design and cost were explored. The effects of different K heterogeneity and remediation design conditions on the length of remediation period, the influence of & / #61548 / anisotropy of K, correlation between K and Kd, and Kd and & / #61537 / , and the fraction of equilibrium sorption sites (f) on the pump-and-treat (P& / T) design and cost were the other studied subjects. In this study, simulation-optimization approach, in which a groundwater flow and contaminant transport simulation model was linked with a genetic algorithm (GA) library, was used. Results showed that not only the amount of PCE mass initially present in the aquifer was important in terms of P& / T design, cost and remediation time, but also the location and size of the high and low K regions defined by & / #955 / lnK as well as the magnitudes of K represented by geometric mean and & / #963 / 2lnK were influential. It was also found that P& / T designs utilizing higher numbers of wells with lower pumping rates may be more robust predicting the time-to-compliance compared to a single well with higher pumping rate for aquifers heterogeneous in K. Homogenous Kd assumption might cause serious error in both the design and the cost of remediation. The magnitude of this error may change depending on the spatial distribution of K and Kd, & / #955 / lnKd, & / #963 / 2lnKd and & / #963 / 2lnK. The effect of heterogeneity in & / #61537 / on the design and cost of remediation may or may not be significant depending on K, Kd and & / #61537 / distributions, & / #61548 / ln& / #61537 / and & / #963 / 2ln& / #61537 / . Increased amount of kinetically sorbed mass defined by decreased f value resulted in more costly remediation.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/3/12610559/index.pdf |
| Date | 01 May 2009 |
| Creators | Gungor Demirci, Gamze |
| Contributors | Aksoy, Aysegul |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | Ph.D. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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