skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Modelling flow to leachate wells in landfills

Abstract

Vertical wells are frequently used as a means of controlling leachate levels in landfills. They are often the only available dewatering option for both old landfills without any basal leachate collection layer and for newer sites where the installed drainage infrastructure has failed. When the well is pumped, a seepage face develops at the entry into the well so that the drawdown in the surrounding waste will not be as great as might be expected. The numerical groundwater flow model MODFLOW-SURFACT, which contains the functionality to model seepage surfaces, has been used to investigate the transient dewatering of a landfill. The study concludes that the position of the seepage face and information about the characteristics of the induced seepage flow field are important and should not be neglected when designing wells in landfills.

Authors:
; ;
Publication Date:
OSTI Identifier:
20875632
Resource Type:
Journal Article
Resource Relation:
Journal Name: Waste Management; Journal Volume: 24; Journal Issue: 3; Other Information: DOI: 10.1016/j.wasman.2003.11.010; PII: S0956053X03002307; Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; DRAINAGE; DRAWDOWN; FLOW MODELS; GROUND WATER; SANITARY LANDFILLS; WASTES; WATER POLLUTION; WATER POLLUTION CONTROL; WATER REMOVAL; WELLS

Citation Formats

Al-Thani, A.A., Beaven, R.P., and White, J.K. Modelling flow to leachate wells in landfills. United States: N. p., 2004. Web. doi:10.1016/j.wasman.2003.11.010.
Al-Thani, A.A., Beaven, R.P., & White, J.K. Modelling flow to leachate wells in landfills. United States. doi:10.1016/j.wasman.2003.11.010.
Al-Thani, A.A., Beaven, R.P., and White, J.K. 2004. "Modelling flow to leachate wells in landfills". United States. doi:10.1016/j.wasman.2003.11.010.
@article{osti_20875632,
title = {Modelling flow to leachate wells in landfills},
author = {Al-Thani, A.A. and Beaven, R.P. and White, J.K},
abstractNote = {Vertical wells are frequently used as a means of controlling leachate levels in landfills. They are often the only available dewatering option for both old landfills without any basal leachate collection layer and for newer sites where the installed drainage infrastructure has failed. When the well is pumped, a seepage face develops at the entry into the well so that the drawdown in the surrounding waste will not be as great as might be expected. The numerical groundwater flow model MODFLOW-SURFACT, which contains the functionality to model seepage surfaces, has been used to investigate the transient dewatering of a landfill. The study concludes that the position of the seepage face and information about the characteristics of the induced seepage flow field are important and should not be neglected when designing wells in landfills.},
doi = {10.1016/j.wasman.2003.11.010},
journal = {Waste Management},
number = 3,
volume = 24,
place = {United States},
year = 2004,
month = 7
}
  • In modern society, production of industrial and domestic waste is increasing so much that waste disposal has become a serious problem in many countries in terms of both difficulty in obtaining a location for waste disposal and concern for the hazardous effects upon the human-environmental system. In Japan, combustible waste is burned in an incinerator and the cinders are buried in landfills together with incombustible waste. These buried substances are degraded by soil bacteria and the physico-chemical milieu existing underground. This requires a great deal of time. However, leachate from the waste landfill is unceasingly dispersed into the environment throughoutmore » the degradation period. It is known that leachate contains various kinds of chemicals both organic and inorganic, resulting from the degradation process. Leachate should therefore be examined from the point of view of both environmental pollution and hazardous effects on human health. In an attempt to evaluate the mutagenicity of leachate, the authors endeavored to establish some methods. They developed a protocol for the preconcentration of mutagens in the leachate and for the examination of the mutagenicity of leachate obtained from waste landfills in Japan using the Salmonella typhimurium/mammalian-microsome system (Ames test).« less
  • This article describes the origins of sanitary landfill leachates, their potential for contamination of surrounding soil and groundwater, and characterization and techniques for treating this extremely high-strength municipal wastewater to required standards by biological processes. Topics include leachate characterization, effluent standards and treatment by two stage activated sludge process.
  • The presence, transport, and ultimate fate of heavy metals in landfill leachate are discussed. The influence of chemical activity and complexation on the behavior of metals in such environments is investigated. Leachates generated in experiments had high concentrations of dissolved ions and organic and inorganic ligands. These substances favored the removal of heavy metals primarily by precipitation as sulfides. This removal was enhanced by the increased stabilization rates and filtering action promoted by the recirculation of leachate through the landfill mass. (1 diagram, 13 graphs, 15 references, 2 tables)
  • Controlling gas and leachate production is a primary objective of sound landfill management. Gases, composed mainly of carbon dioxide and methane, are formed during the decomposition of solid wastes. Leachate forms as water passes through the refuse, dissolving out chemicals. Three basic methods for controlling gas and leachate production are presented: managing production; directing gas or leachate movement; and treating the gas or leachate. Determining whether it would be more advantageous to increase or reduce the gas and leachate production is the first step in choosing a control method. (3 graphs, 3 tables)
  • There has been considerable debate regarding the chemical characterization of landfill leachate in general and the comparison of various types of landfill leachate (e.g., hazardous, codisposal, and municipal) in particular. For example, the preamble to the US EPA Subtitle D regulation (40 CFR Parts 257 and 258) suggests that there are no significant differences between the number and concentration of toxic constituents in hazardous versus municipal solid waste landfill leachate. The purpose of this paper is to statistically test this hypothesis in a large leachate database comprising 1490 leachate samples from 283 sample points (i.e., monitoring location such as amore » leachate sump) in 93 landfill waste cells (i.e., a section of a facility that took a specific waste stream or collection of similar waste streams) from 48 sites with municipal, codisposal, or hazardous waste site histories. Results of the analysis reveal clear differention between landfill leachate types, both in terms of constituents detected and their concentrations. The result of the analysis is a classification function that can estimate the probability that new leachate or ground water sample was produced by the disposal of municipal, codisposal, or hazardous waste. This type of computation is illustrated, and applications of the model to Superfund cost-allocation problems are discussed.« less