Source Control Early Action Focused Feasibility Study

Transcription

1 Source Control Early Action Focused Feasibility Study Empirical Mass Balance Model Results or the Lower Passaic River Edward A. Garvey, PhD, PG Malcolm Pirnie, Inc. Remedial Options Workgroup Meeting June

2 Outline Components o the Conceptual Site Model (CSM) Physical-Geochemical Setting Human and Ecological Setting Framework or the Empirical Mass Balance Model Mass Balance Results Historical Record and Remedial Scenario Forecasts Conclusions 2

3 Components o the CSM Risk Assessment Components Human Cancer Impacts Ingestion and Depuration Human Non-Cancer Impacts Exposure Point Concentrations Exposure Duration Ecological Impacts Physical- Geochemical Components Advection and Tidal Exchange Contaminant Concentrations Sediment Resuspension External Sources Geochemical Processes Sediment Inventory 3

4 Physical Setting Dundee Dam 4

5 History o Dredging in the Lower Passaic Dredged Sediment Volume by Year Physical Setting 1981 to to to to to 1962 Below RM2 Above RM2 Little dredging post 1950 Year Range 1951 to to to to to to to x x x x x 10 7 Volume o Sediment Dredged (cy) 5

6 Physical Setting River Channel Elevation and the Constructed Depths o the Lower Passaic River Channel 0 NGVD2 9 Mean Low Water Mean Low Water Elevation (eet NGVD29) River Bottom Pre-1950s Channel Construction 30' Channel Depth (MLW) 20' Channel Depth (MLW) 16' Channel Depth MLW 10' Channel Depth (MLW Navigational Channel Centerline Bathymetry Navigational Channel Depth Navigational Channel Depth + 2' River Miles 6

7 Physical Setting Passaic River Cross Section and Sediment Type Cross-Sectional Area (square eet) River cross section is greater than 3,700 sq t below RM % River Mile Percent Grain o River Size Bottom Distribution Area 100% 80% 60% 40% 20% 0% Fine-grained Coarse-grained Fine-grained sediment covers 80% or more o the river bottom when the cross-sectional area is >3,700 sq t Cross-Sectional Area (square eet) 7

8 Depositional and Erosional Areas Physical Setting Depositional Zone Erosional Zone 8

9 The History o Contamination is Recorded in the Sediments 2,3,7,8 - TCDD (ug/kg) Chemical Setting Approximate Year o Deposition RM 1.4 RM 2.2 RM 7.8 RM 11 RM

10 Contaminant Inventory in the Lower Passaic River Chemical Setting Silt PCBs Sand Dioxin DDT Hg, Cd, Cr, Cu, Pb, As, PAHs Red Clay 10

11 Chemical Setting Inventory Results Mercury Total DDT 2,3,7,8-TCDD Total PCB Sediment inventories coincide with areas o deposition, not proximity to source 2,3,7,8-TCDD (mg/m 2 ) 2,3,7,8-TCDD MPA (mg/m 2 ), Mercury MPA or Total PCB MPA (g/m 2 ) Mercury (g/m 2 ) or Total PCB Inventory (g/m 2 ) River Mile 11 Total DDT (g/m 2 ) Total DDT MPA (g/m 2 )

12 Framework o the Empirical Mass Balance Model 12

13 Schematic o Box Model or the Lower Passaic River Empirical Mass Balance EMBM Upper Passaic Saddle River Third River Second River CSO/SWO Resuspension Newark Bay Dundee Dam Lower Passaic River Water Sediment 13

14 Schematic o Box Model or the Lower Passaic River Empirical Mass Balance EMBM Upper Passaic Saddle River Third River Second River CSO/SWO Resuspension Newark Bay C sur sed = DD * Water C Sediment DD where + Dundee Dam i NB * C NB DD + + Lower Passaic River * + Tribs NB + C Tribs Tribs + CSO / SWO CSO / SWO * + C CSO / SWO resusp = raction o solids rom source i + resusp * C resusp 14 C i = contam inant concentration in source i

15 2005 Schematic Total PCBs o (ug/kg) Box Model or the Lower ,000 10, ,000 Passaic River Empirical Mass Balance EMBM Approximate Year o Deposition Upper Passaic C sur sed = Water Sediment 15 RM 1.4 RM 2.2 RM 7.8 RM 11 RM 12.6 DD * C DD where + Saddle River Dundee Dam C i i NB = = * C NB DD + + Third River Second River Resuspension CSO/SWO Lower Passaic River * + raction Tribs NB + o contam inant C Tribs Tribs + solids CSO / SWO CSO / SWO C CSO / SWO resusp * + rom source i concentration in Newark Bay + source i resusp * C resusp

16 EMBM Contaminants Used in the EMBM Metals PCDD/F Pesticides PAHs Lead Mercury 2,3,7,8-TCDD Total TCDD DDE Benzo[a]pyrene Fluoranthene PCB Congeners BZ 52 BZ

17 EMBM Formulation or the EMBM Five unknowns + 1 DD to resusp C resusp narrowly constrained by range o sediment conditions Nine equations One or each o nine contaminants Solve by optimization Minimize overall level o error or all ive unknowns or given C resusp 17

18 Empirical Mass Balance Model Results 18

19 Solids Balance or the Lower Passaic River: External Solids Dominant Tributaries ~5% 5% CSO/SWO ~5% 4% Resuspended Lower Passaic Lower River Passaic Integrated River Sediment Sediments Length- Weighted ~10% Average 12% EMBM Upper Upper Passaic Passaic River River ~40 38% % Newark Bay ~40 41% % 19

20 Solids Balance or the Lower Passaic River: Internal Solids Dominant Upper Passaic River River 2% ~2% Newark Bay ~1 1% % Tributaries 0% ~0% CSO/SWO ~0 0% % EMBM Resuspended Lower Passaic Lower River Integrated Passaic Sediment River Sediments 1990s ~97% 20

21 Source Concentrations or 2,3,7,8-TCDD Source Concentrations or 2,3,7,8-TCDD Lower Passaic River Surace Sediments Upper Passaic River Upper Passaic - Core 2 Tributaries Tributaries CSO & SWO CSO&SWO Newark Bay Newark Bay Historical Lower Passaic Sediments Lower Passaic Integrated Concentration (ug/kg) 21 EMBM

22 2,3,7,8-TCDD Mass Balance % Solids Balance EMBM Sediment resuspension responsible or more than 95% o the 2,3,7,8-TCDD 2,3,7,8-TCDD Similar Compounds Total TCDD Light PCBs Lower Historical Passaic Lower Integrated Passaic Sediments Newark Bay Upper Passaic Tributaries CSO&SWO 22

23 Source Concentrations or PCBs BZ Source Concentrations or PCB BZ Lower Passaic River Surace Sediments 0 Upper Passaic - Core River 2 Tributaries CSO CSO&SWO & SWO Newark Bay Lower Historical Passaic Integrated Lower Passaic Sediments Concentration (ug/kg) 23 EMBM

24 PCB BZ Mass Balance % Solids Balance EMBM Sediment resuspension and Upper Passaic each responsible or 40% o BZ PCB Similar Compounds Heavy PCBs DDTs Mercury Historical Lower Passaic Lower Passaic Integrated Sediments Newark Bay Upper Passaic Tributaries CSO&SWO 24

25 Benzo(a)Pyrene Mass Balance % Solids Balance EMBM Upper Passaic River responsible or ~ 75% o Benzo(a)Pyrene Benzo(a)pyrene Similar Compounds LMW PAHs HMW PAHs Historical Lower Passaic Lower Passaic Integrated Sediments Newark Bay Upper Passaic Tributaries CSO&SWO 25

26 EMBM Lead Mass Balance % Solids Balance Each o the sources is roughly equal in magnitude Lead Similar Compounds Copper Chlordane Dieldrin Historical Lower Passaic Lower Passaic Integrated Sediments Newark Bay Upper Passaic Tributaries CSO&SWO 26

27 The Historical Record and Remedial Scenario Forecasts 27

28 Forecasts Basis or Forecasts: Dated Cores 100 Mercury Concentration (mg/kg) 10 1 RM 1.4 RM 2.2 RM 7.8 RM 11 RM Approximate Year o Deposition 28

29 Forecasts Basis or Forecasts: Dated Cores 100 RM 1.4 RM 2.2 Mercury Concentration (mg/kg) 10 1 Hal Lie = 18 years RM 7.8 RM 11 RM Approximate Year o Deposition 29

30 Remedial Scenarios 8 Forecasts No Action 7 Primary Erosion/ Inventory Area Remediation Inventory 3 2 Area o Focus Remediation Erosion 1 Flats Area o Focus 0 30

31 Forecasts 2,3,7,8-TCDD Forecasted Surace Sediment Concentrations Concentration (ug/kg) Hal lie = 17 years Area o Focus Remediation No Action Time ~40 year improvement to any threshold post- AOF Remediation Primary Erosion/Inventory Area Remediation Sediment Cores RM1.4 RM2.2 RM7.8 RM11 RM

32 Concentration (ug/kg) 10,000 1, Total PCBs Forecasted Surace Sediment Concentrations Hal lie = 14 years Area o Focus Remediation Time ~10 year improvement to any threshold post- AOF Remediation No Action Primary Erosion/Inventory Area Remediation Forecasts Sediment Cores RM1.4 RM2.2 RM7.8 RM11 RM

33 Mercury Forecasted Surace Sediment Concentrations Forecasts 100 Sediment Cores RM1.4 RM2.2 Concentration (mg/kg) 10 1 ~10 year improvement to any threshold post- AOF Remediation No Action Primary Erosion/Inventory Area Remediation RM7.8 RM11 RM Hal lie = 18 years Area o Focus Remediation Time 33

34 100 High Molecular Weight PAHs Forecasted Surace Sediment Concentrations Forecasts Sediment Cores RM1.4 RM2.2 Concentration (mg/kg) 10 No Decline Area o Focus Remediation Time No Action Primary Erosion/ Inventory Area Remediation RM7.8 RM11 RM

35 Conclusions o the EMBM External contaminant sources (by themselves) cannot account or the observed COPC concentrations. Sediment re-suspension is a major contributor to the contaminant burden o recently deposited sediments. Surace sediments originate rom the Upper Passaic River and Newark Bay in roughly equal proportions. Minor solids contributions rom historical sediment resuspension, tributaries, and CSO/SWOs. CSO/SWOs and the tributaries play lesser roles or most contaminants. 1 More important or lead, dieldrin, chlordane and copper 1 1. These bullets were modiied rom the original presentation to be more consistent with the oral presentation and the EMBM report. 35

36 Conclusions o the EMBM (cont.) Re-suspension o legacy sediments (i.e., the historical inventory) = ~10 percent o the total annual solids deposition >95% o annual 2,3,7,8-TCDD load Single largest source o : - PCBs - DDT+DDE+DDD - Mercury Upper Passaic River is the major source o PAHs and an important source o PCBs and mercury Newark Bay solids serve to dilute contamination in Lower Passaic River sediments. Newark Bay represents about 25 % o mercury load 36

37 Conclusions o the EMBM (cont.) Surace sediment concentrations show very slow declines post Total PCB has shortest hal lie, at 14 years. LMW PAHs, HMW PAHs, and dieldrin have not declined since 1980 and may be increasing slightly with time. Remediation o the Area o Focus o can signiicantly reduce uture surace concentrations o dioxin, reducing the recovery time by ~40 years relative to No Action. Remediation o the Area o Focus can also improve surace concentrations o PCBs, DDT, and mercury, but to a lesser degree, improving recovery by ~10 to 15 years relative to No Action. Remediation o the Primary Erosion and Primary Inventory Zones results in only marginal improvements relative to No Action. 37