Stochastic analysis of dense nonaqueous phase liquid dissolution in naturally heterogeneous subsurface systems

Field-scale Dense Nonaqueous Phase Liquid (DNAPL) dissolution in three-dimensional heterogeneous subsurface systems is investigated using a stochastic approach that treats the variability of flow properties as three-dimensional random fields. A steady-state, quasi-static DNAPL saturation distribution in a source zone is derived, based on the previous research to describe the field-scale nonuniform residual DNAPL distribution. A local-scale dissolution model is generalized from the laboratory experimental results. Effective transport and dissolution properties are obtained by a stochastic analysis, which includes nonstationarity in the concentration field to address both boundary and downstream effects. An extrapolation of the effective properties is performed for the large spatial variability of hydraulic and dissolution parameters. The extrapolation is evaluated using a unique two-zone model that simplifies the continuous DNAPL distribution to two components: low permeability lens zone with high DNAPL saturation and a surrounding permeable zone with low DNAPL saturation. The agreement between the two-zone model results with stochastic solutions demonstrates the adequacy of the extrapolation of the latter. Four field sites with different geological settings and hydraulic characteristics are evaluated using effective properties: the Borden site, the Cape Cod aquifer, the Savannah River Site and the Hanford site.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Civil and Environmental Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2003

Author dc:creator

• Fu, Xin, 1973-

Advisor dc:contributor.advisor

• Lynn W. Gelhar.

• Civil and Environmental Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/29283

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/29283