HR: 10:30h
AN: B22A-01 INVITED     [Abstracts]
TI: Analytical Models for Plumes With Biodegradation in Both Fringe and Core
AU: * Lerner, D N
EM: d.n.lerner@shef.ac.uk
AF: Groundwater Protection and Restoration Group, Kroto Research Institute, University of Sheffield, Broad Lane, SHEFFIELD, S3 7HQ United Kingdom
AU: Gutierrez-Neri, M
EM: cip03mg@shef.ac.uk
AF: Groundwater Protection and Restoration Group, Kroto Research Institute, University of Sheffield, Broad Lane, SHEFFIELD, S3 7HQ United Kingdom
AB: The classical analytical solutions for biodegrading plumes take account of advection and dispersion, and represent biodegradation by a first order decay term (Domenico 1987). It has long been recognised that biodegradation rates are more complex, with the potential for different rates to occur for each degradation pathway. In particular, oxidation of organic carbon by oxygen and nitrate at the fringes of a plume is often effectively instantaneous, and is controlled by the rate of dispersive mixing between the plume and background water. This has led to a new generation of analytical solutions (eg Ham et al. 2004), and the production of a new screening tool for predicting plume lengths, CoronaScreen (www.shef.ac.uk/corona). However, such models do not always predict the behaviour of plumes in the field, possibly because they do not take account of the slow, anaerobic, biodegradation processes in the plume. Although such core processes may be slow, they take place in a relatively large volume, and so can make a significant contribution to the overall biodegradation rate. We present a new analytical solution to the reactive transport problem which includes both instantaneous fringe and first order core processes, and compare it to field data. We close with words of caution about applying such simple, analytical solutions to real field problems which are frequently complex, heterogeneous, have unknown source terms, and are poorly described by field data.
DE: 0412 Biogeochemical kinetics and reaction modeling (0414, 0793, 1615, 4805, 4912)
DE: 0418 Bioremediation
DE: 0466 Modeling
DE: 1832 Groundwater transport
SC: Biogeosciences [B]
MN: Fall Meeting 2005