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Notes from Rao 2/13/2007 2:07:37 PM Environmental Assessment of Sediments and Water in Bayou Grande, Pensacola, FL. Dr. Carl J. Mohrherr Center for Environmental Diagnostics and Bioremediation University of West Florida Dr. Johan Liebens Department of Environmental Studies University of West Florida Dr. K. Ranga Rao Center for Environmental Diagnostics and Bioremediation University of West Florida June 26, 2008 FOREWORD This study is a component of the "Assessment of Environmental Pollution and Community Health in Northwest Florida" supported by a USEPA Cooperative Agreement award X-9745502 to The University of West Florida (Project Director: Dr. K. Ranga Rao). The contents of this report are solely the responsibility of the authors and do not necessarily represent the official views of the USEPA. The study was undertaken because of the increasing concern for environmental pollution and potential impacts on human health in Northwest Florida. It was designed to assess environmental impacts of toxic pollutants in Bayou Grande. Kristal Flanders managed the spatial databases for the project and drafted the maps. Her assistance has been invaluable. Chris Carlton-Franco, Brandon Jarvis, Guy Allard, and Danielle Peterson helped with the fieldwork and some laboratory procedures. Creative Commons License This work is licensed under a Creative Commons Attribution- NonCommercial- NoDerivatives 4.0 International License. i TABLE OF CONTENTS I INTRODUCTION........................................................................................................... 1 II STUDY AREA.............................................................................................................. 2 II.1 Physiography.......................................................................................................................... 2 II.2 Climate.................................................................................................................................... 3 II.3 Urban Development............................................................................................................... 4 II.4 Pensacola Bay and Dredging Activity.................................................................................. 5 II.5 Historical Outline of Bayou Grande .................................................................................... 6 III POLLUTION IN BAYOU GRANDE: LITERATURE REVIEW..................................... 8 III.1 General Pollution History.................................................................................................... 8 III.2 Fecal Coliform Pollution in Bayou Grande ..................................................................... 13 III.3 Total Petroleum Hydrocarbons ........................................................................................ 14 III.4 Polycyclic Aromatic Hydrocarbons (PAHs) .................................................................... 15 III.5 Organochlorinated Compounds........................................................................................ 20 III.6 Trace Metals ....................................................................................................................... 21 IV ENVIRONMENTAL BACKGROUND OF SEDIMENT POLLUTANTS ..................... 26 IV.1 Polychlorinated Biphenyls (PCBs).................................................................................... 26 IV.2 Organochlorinated Compounds........................................................................................ 28 IV.2.1 General Notions ........................................................................................................... 28 IV.2.2 Organochlorinated Pesticides in Sediments and Biota.............................................28 IV.2.2.1 Aldrin and Dieldrin................................................................................................. 28 IV.2.2.2 Endrin ..................................................................................................................... 29 IV.2.2.3 Lindane ................................................................................................................... 30 IV.2.2.4 Chlordane................................................................................................................ 31 IV.2.2.5 DDT ........................................................................................................................ 32 IV.2.2.6 Mirex and Chlordecone .......................................................................................... 33 IV.2.2.7 Endosulfan .............................................................................................................. 36 IV.2.3 Dioxins/Furans............................................................................................................. 37 IV.2.4 Pentachlorophenol (PCP) ........................................................................................... 39 ii IV.3 Metals................................................................................................................................... 40 IV.3.1 Mercury (Hg) ............................................................................................................... 40 IV.3.2 Lead (Pb) ...................................................................................................................... 42 IV.3.3 Cadmium (Cd) ............................................................................................................. 44 IV.3.4 Arsenic (As).................................................................................................................. 46 IV.3.5 Chromium (Cr)............................................................................................................ 47 IV.3.6 Copper (Cu) ................................................................................................................. 49 IV.3.7 Nickel (Ni)..................................................................................................................... 50 IV.3.8 Zinc (Zn)....................................................................................................................... 51 V OBJECTIVES ............................................................................................................ 53 VI METHODS................................................................................................................ 54 VII RESULTS AND DISCUSSION ................................................................................ 60 VII.1 Semivolatile Organic Compounds................................................................................... 60 VII.1.1 Total Petroleum Hydrocarbons................................................................................ 60 VII.1.2 Polycyclic Aromatic Hydrocarbons (PAHs)............................................................ 63 VII.1.2.1 PAHs in surface sediments.................................................................................... 63 VII.1.2.2 PAHs in the water column..................................................................................... 74 VII.1.2.3 PAHs in vibracores................................................................................................ 74 VII.1.2.4 Origins of PAHs in Bayou Grande........................................................................ 80 VII.1.2.5 Pentachlorophenol (PCP) ...................................................................................... 87 VII.2 Dioxins/furans and PCBs ................................................................................................. 88 VII.2.1 Dioxin/furan and PCB TEQ...................................................................................... 88 VII.2.2 Dioxin/furan and PCB TEQ in Bayou Grande Sediments..................................... 88 VII.2.3 Total Dioxin/Furan Mass Concentrations in Surface Sediments .......................... 92 VII.2.4 Total Dioxin/Furan Mass Concentrations in Vibracores....................................... 93 VII.2.5 Origin of Dioxins/Furans in Bayou Grande ............................................................ 94 VII.2.6 Total PCB Concentrations in Surface Sediments ................................................... 98 VII.2.7 Total PCB Concentrations in Vibracores.............................................................. 101 VII.2.8 Origin of PCBs in Bayou Grande........................................................................... 101 VII.2.9 Dioxin-like PCB Concentrations in Surface Sediments ....................................... 109 VII.2.10 Degradation of PAHs, PCBs, and Dioxins/ Furans in Sediments...................... 113 VII.2.11 Dioxins/Furans in Bayou Grande Sediments and Seafood Tissues................... 120 VII.2.12 PCBs in Bayou Grande Sediments and Seafood Tissues.................................... 123 VII.3 Pesticides.......................................................................................................................... 126 VII.4 Trace Metals.................................................................................................................... 129 VII.4.1 Trace Metal Concentrations in Surface Sediments .............................................. 129 VII.4.2 Origin of Trace Metals in Surface Sediments ....................................................... 140 VII.4.3 Trace Metal Concentrations in Vibracores ........................................................... 144 VII.4.4 Trace Metal Concentrations in Water ..................................................................
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