title: Atmospheric dispersion of PCB from a contaminated Lake Michigan harbor.
abstract: Indiana Harbor and Ship Canal (IHSC) in East Chicago is an industrial waterway on Lake Michigan and a source of PCBs to Lake Michigan and the overlying air. We hypothesized that IHSC is an important source of airborne PCBs to surrounding communities. We used AERMOD to model hourly PCB concentrations, utilizing emission fluxes from a prior study and hourly meteorology provided by the State of Indiana. We also assessed dispersion using hourly observed meteorology from a local airport and high resolution profiles simulated by the Weather Research and Forecasting model. We found that emissions from IHSC waters contributed about 15% of the observed ΣPCB concentrations close to IHSC when compared on an hourly basis and about 10% of observed annual concentrations at a nearby school. Concentrations at the school due to emissions from IHSC ranged from 0 to 18,000 pg m-3, up to 20 times higher than observed background levels, with an annual geometric mean (GSD) of 19 (31) pg m-3. Our findings indicate that IHSC is an important source of PCBs to East Chicago, but not the only source. Four observed enriched PCB3 samples suggest a nearby non-Aroclor source.
authors.affiliation: Department of Civil & Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, USA.
authors.forename: Andres
authors.initials: A
authors.lastname: Martinez
authors.affiliation: Department of Civil & Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, USA ; School of Urban and Regional Planning, Public Policy Center, The University of Iowa, IA, USA.
authors.forename: Scott N
authors.initials: SN
authors.lastname: Spak
authors.affiliation: Department of Civil & Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, USA.
authors.forename: Nicholas T
authors.initials: NT
authors.lastname: Petrich
authors.affiliation: Department of Civil & Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, USA.
authors.forename: Dingfei
authors.initials: D
authors.lastname: Hu
authors.affiliation: Department of Chemical and Biochemical Engineering, The University of Iowa, Iowa City, IA, USA.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Carmichael
authors.affiliation: Department of Civil & Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, USA.
authors.forename: Keri C
authors.initials: KC
authors.lastname: Hornbuckle
keywords: 4-monochlorobiphenyl (PCB3); AERMOD; Indiana Harbor and Ship Canal (IHSC); Polychlorinated Biphenyls (PCBs); Weather Research and Forecasting Model (WRF)