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Partnership for Environmental Research and Community Health (PERCH). Environmental quality of surface soils in public places in NW Florida. Johan Liebens Department of Environmental Studies University of West Florida Carl J. Mohrherr and K. Ranga Rao
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Partnership for Environmental Research and Community Health (PERCH) Environmental quality of surface soils in public places in NW Florida Johan Liebens Department of Environmental Studies University of West Florida Carl J. Mohrherr and K. Ranga Rao Center for Environmental Diagnostics and Bioremediation University of West Florida
Introduction • Soils in many urban areas have been found to be polluted with trace metals. • NW Florida has water, sediment, air pollution problems. • Surface soils in NW Florida polluted? • Soil pollution has only been studied at/near former industrial sites.
Objectives • Dioxins/furans, polycyclic aromatic hydrocarbons (PAHs), trace metals. • Assessment of trace metal pollution in surface soils in public places (parks, playgrounds, sports facilities). • pollution levels • spatial distribution • potential origin • urban vs. rural • influence traffic • influence CCA treated wood • influence soil characteristics • speciation (bioavailability) of trace metals
Objectives • Dioxins/furans, polycyclic aromatic hydrocarbons (PAHs), trace metals. • Assessment of trace metal pollution in surface soils in public places (parks, playgrounds, sports facilities). • pollution levels • spatial distribution • potential origin • urban vs. rural • influence traffic • influence CCA treated wood • influence soil characteristics • speciation (bioavailability) of trace metals
Trace metal concentrations (n = 126) RSCTL = Residential Soil Cleanup Target Level
Anthropogenic trace metal pollution Enrichment factor: • Concept: ratio of concentration in sample to background concentration • EFmetal = (Conc. metal/Conc. Al)sample / (Conc. metal/Conc. Al)background • < 2 unpolluted, 2 - 10 polluted, > 10 strongly polluted
Potential trace metal origin: Factor analysis (with Fe, Al) Factor loading plot Factor 2 Factor 1
Hot spot analysis • Do sites with high concentrations tend to cluster spatially? • Assigns a sampling site to a hot spot if the values for the site and surrounding sites are high compared to rest of dataset. • Output is Z score. • Run on Pollution Load Index (PLI) for four anthropogenic metals.
Sequential extraction • Fractions of trace metals extracted in stepwise procedure with gradually more "aggressive" compounds: • Water extractable • Exchangeable • Oxide-bound • Organic matter (OM)-bound • Residual phase (parent material)
Sequential extraction • Trace metals extracted in stepwise procedure with gradually more "aggressive" compounds: • Water extractable • Exchangeable • Oxide-bound • Organic matter (OM)-bound • Residual phase (parent material) bioavailable fraction
Conclusions • Most trace metals do not exceed RSCTL, have relatively low anthropogenic pollution levels. • As exceeds RSCTL throughout area, has largest bioavailable fraction. • Cu, Pb, Zn, Hg have anthropogenic origin. • Cr, Ni are associated with parent material and predominantly in residual phase. • Small difference between concentrations in urban and rural areas, but elevated concentrations in Palafox Industrial Corridor.
Acknowledgements • PERCH/CEDB personnel. • EPA cooperative agreement X-97455002. • Student assistants: Eric Joyner, Kristal Walsh, Michael Somerville.
PERCH Project Center for Environmental Diagnostics and Bioremediation (CEDB) Sediment Pollutant Profiles in the Escambia Bay/River System and Pensacola Bayous Carl J. Mohrherr, CEDB UWF Johan Liebens, ES UWF Joe Lepo, CEDB UWF K. R. Rao, CEDB UWF PERCH Symposium on Project Outcomes
Pensacola Estuaries Determined Sediment Pollutant Profiles for the Escambia Bay/River System and 3 Bayous: B. Texar, B. Chico, and B. Grande. Three Bayous have hotspots that frequently exceed SQAG for metals, PAHs, PCBs, dioxins Petroleum hydrocarbons were high in two Bayous- No SQAGs Escambia Bay/River sediments have lower levels of pollutants Exceptions: Arsenic and DDT were higher Bayou Grande Bayou Chico
Bayou Texar • Elongated estuary receives flow from Carpenter’s Creek • Residential-light commercial watershed with Superfund Fund plumes • Metals Map: Pollutant Load Index: shows Hot Spot • Sedimentation and pollution greater in the northern portion of the bayou • Mean total TEQs >TEL • PCBs lower than other Bayous • PAH conc. > TEL • PB, Hg, Cu, Zn > PEL • Cr, Cd, As >TEL • Petroleum hydrocarbons high • Sedimentation also at mouth Superfund Sites
spoil island Bayou Chico • Small Bayou with three creeks • Major Impacts • Sedimentation • Dredging and spoils disposal over last 90 years • Dredge spoils disposed in nearby bay or about the bayou • Catchment areas-Hot Spots • Major industrial pollution • Waste sites see green arrows • Plume impacts? • Pollutants: • Cu, Pb, Hg, Zn> PEL As, Cr, Cd >TEL; • PCBs, dioxins > PEL PAHs >TEL • Petroleum hydrocarbons (ASTs)
Bayou Grande • Elongated with embayments • Eastern embayments highly polluted • PAHs • PAH hot spots exceed PEL • Deeper sediments have naphthalene contamination as do surface sediments near NAS • Suggests groundwater contamination impact Bayou Grande Pollutant Load Index Map-Cu, Hg, Pb, Zn
Continued: Bayou Grande • Metals • Cd, Pb, Zn >PEL • As, Cr, Hg, Ni >TEL • PCBs and dioxins Exceed SQAG Bayou Grande Pollutant Load Index Map-Cu, Hg, Pb, Zn
Escambia Bay and River • Escambia Bay is part of the Pensacola Bay System • 36 miles2 • Escambia River is 230 miles with about 58 miles in Florida • Past impacts from Industries and Utilities • 1969 Monsanto PCB spill • Several Bridges: 90 Causeway is likely most impacting • ~1970 Environmental crash of bay, Followed by US EPA studies and enforcement actions Escambia River Escambia Bay
Escambia Map: Pollutant Load Index Hg, Cu, Pb, ZnIndex values are very low-no metal hot spots Escambia Bay Escambia River and upper bay: • Most pollutant concentrations were low compared to the bayous. • Arsenic was the only metal to consistently exceed SQAG
Organochlorine Pesticides • Detections were minimal in Bayous Texar and Grande • Not analyzed in Chico • Escambia River and wetlands DDT present
ESCAMBIA PCBs Escambia Bay Upper Escambia Bay and River and lower wetlands.
Contaminated Plumes • Each of the three bayous: Texar, Chico, and Grande are adjacent to Plumes from Superfund sites. • B. Texar: AGRICO Fluoride Plume is entering Bayou waters • No evidence that Escambia Treating Company naphthalene plume has impacted the Bayou • No evidence that radium from AGRICO has impacted the bayou • B. Grande: naphthalene is present in deep & surface bayou sediments. NAS Pensacola could be a source • B. Chico: no demonstrated impact from the American Creosote Site or OmniVest Landfill
Future of contaminated sediments • Most sediment organics will tend to degrade slowly, metals are more persistent • Flushing • It sends the pollutants elsewhere • Sediment remediation of Bayous and Bay is not being pursued by state or federal entities • Currently TMDLs under CWA section 303(d) • For Fecal bacteria in water column • Sediment contaminants are not covered
Past Past END Present Future