title: Evaluating fugacity models for trace components in landfill gas.
abstract: A fugacity approach was evaluated to reconcile loadings of vinyl chloride (chloroethene), benzene, 1,3-butadiene and trichloroethylene in waste with concentrations observed in landfill gas monitoring studies. An evaluative environment derived from fictitious but realistic properties such as volume, composition, and temperature, constructed with data from the Brogborough landfill (UK) test cells was used to test a fugacity approach to generating the source term for use in landfill gas risk assessment models (e.g. GasSim). SOILVE, a dynamic Level II model adapted here for landfills, showed greatest utility for benzene and 1,3-butadiene, modelled under anaerobic conditions over a 10 year simulation. Modelled concentrations of these components (95,300 microg m(-3); 43 microg m(-3)) fell within measured ranges observed in gas from landfills (24,300-180,000 microg m(-3); 20-70 microg m(-3)). This study highlights the need (i) for representative and time-referenced biotransformation data; (ii) to evaluate the partitioning characteristics of organic matter within waste systems and (iii) for a better understanding of the role that gas extraction rate (flux) plays in producing trace component concentrations in landfill gas.
authors.affiliation: Integrated Waste Management Centre, Sustainable Systems Department, Building 61, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK.
authors.forename: Sophie
authors.initials: S
authors.lastname: Shafi
authors.forename: Andrew
authors.initials: A
authors.lastname: Sweetman
authors.forename: Rupert L
authors.initials: RL
authors.lastname: Hough
authors.forename: Richard
authors.initials: R
authors.lastname: Smith
authors.forename: Alan
authors.initials: A
authors.lastname: Rosevear
authors.forename: Simon J T
authors.initials: SJ
authors.lastname: Pollard
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001554:Benzene / Q000032:analysis; D001673:Biodegradation, Environmental; D002070:Butadienes / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D005740:Gases / Q000032:analysis*; D055593:Geological Phenomena; D005844:Geology; D008697:Methane / Q000032:analysis; D015233:Models, Statistical; D012037:Refuse Disposal; D018570:Risk Assessment / Q000379:methods; D014241:Trichloroethylene / Q000032:analysis; D014752:Vinyl Chloride / Q000032:analysis; D014835:Volatilization; D014919:Wind
chemical_list: D000393:Air Pollutants; D002070:Butadienes; D005740:Gases; D014241:Trichloroethylene; D001554:Benzene; C031763:1,3-butadiene; D008697:Methane; D014752:Vinyl Chloride