APPENDIX B Results of Cross-Channel Monitoring

APPENDIX B

Results of Cross-Channel Monitoring

Draft Contractor Document: Subject to Continuing Agency Review

Not USGS Approved (Revised September 2006)

Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Report to the U.S. Army Corp of Engineers

Timothy P. Wilson, Ph.D.

U.S. Geological Survey

West Trenton, N.J.

Fig 6C – EW velocity at M6

Discussion of velocity profiles at M2 and M6

New fig 8. 2/23/2007

Discussion on PCB homologs,

PCB homologs Dec. 6

Dissolved loads on Dec. 6

1



Contents

Introduction …………………………………………………………………………....12

Terminology……………………………………………………………………………14

Overview of Methods……………………………………………………………….....16

Sampling………………………………………………………………………..16

Calculation of chemical concentrations……………………………………..21

Calculation of flow and sediment load mass balance……………………...23

Background Conditions ……………………………………………………………....27

Salinity and Turbidity…………………………………………………………..29

Background Chemistry………………………………………………………..39

Pre- and Post-Dredging Sediment Chemistry………………….…..42

Pre-dredging Sediment Load and Mass Balance……………..…...69

Net Sediment Load to Newark Bay …………………………..……..74

Evaluation of Concentrations and Chemistry of Suspended Sediment during

Dredging…………………………………………………………………………….76

December 5 - a.m. …………………………………………………………....77

Suspended Sediment…………………………………………….…...78

Turbidity…………………………………………………………….…..78

Sediment Chemistry…………………………………………………..79

December 5 – p.m. …………………………………………………………...80

Suspended Sediment ………………………………………………...80

Turbidity………………………………………………………………...80

Water Salinity and Velocity…………………………………………...81

Comparison of Turbidity during Consecutive Tide Cycles…….…..82

Sediment Load and Mass Balance……………………………….....83

Sediment Chemistry……………………………………………….….84

December 6 – A.M.…………………………………………………………...92

Water Salinity and Velocity…………………………………………..94

Sediment Chemistry…………………………………………………..94

December 6 – p.m.…………………………………………………………....95

Suspended Sediment………………………………………………....96

Turbidity………………………………………………………………...96

Water Salinity and Velocity…………………………………………...97

Comparison of Turbidity during Consecutive Tide Cycles………...97

2



Contents - Continued

Sediment Loads and Mass Balance……………………………....98

Sediment Chemistry……………………………………………….100

Water Chemistry and Mass Balance …………………………....101

December 7-A.M. ………………………………………………………….111

Suspended Sediment………………………………………………111

Turbidity…..…………………………………………………………112

Water Salinity and Velocity………………………………………..112

Comparison of Turbidity during Consecutive Tide Cycles……..113

Sediment Loads and Mass-Balance……………………………...113

Sediment Chemistry………………………………………………..115

December 7 – p.m. ………………………………………………………...116

Turbidity……………………………………………………………...116

Water Salinity and Velocity………………………………………...117

Sediment Loads and Mass Balance ……………………………..117

December 8…………………………………………………………………124

Suspended Sediment……………………………………………...124

Turbidity……………………………………………………………..124

Water Salinity and Velocity………………………………………..125

Comparison of Turbidity during Consecutive Tide Cycles…….126

Sediment Loads and Mass Balance……………………………..127


December 10 ………………………………………………………………136

Suspended Sediment……………………………………….……..136

Turbidity……………………………………………………….…….137

Water Salinity and Velocity………………………………….…….137

Comparison of Turbidity during Successive Tide

Cycles……………………………………………………………….138

Sediment Load and Mass Balance………………………………138


December 10 – p.m. ……………………………………………...141

Suspended Sediment……………………………………….……..141

Turbidity……………………………………………………….…….142

Water Salinity………………………………………………….……142

Comparison of Turbidity during Successive Tide

Cycles…………………………..………………………..............…143

Sediment Loads and Mass Balance ……………………………..143

Sediment Chemistry……………………………………….144

Discussion and Summary…………………………………………………………154

References …………………………………………………………………………165

3



Figures

Figure 1. Schematic diagra.m. of mooring locations and water flow in the dredge area, Harrison Reach of the Lower Passaic River, Newark New Jersey

…………………………………………………………………………………………...15

2. Cross-sectional profiles showing ADCP bin areas for (a) line M12 and (b) line

M56; Harrison Reach, Lower Passaic River, Newark, New Jersey,

2005……………………………………………………………………………..26

3. Location of the bed sediment cores and the dredging activity during the Pilot

Program, Lower Passaic River, Newark, New Jersey, 2005……………..28

4. Water elevation at mooring 2 and periods of dredge activity in the Lower

Passaic River, December 4-10, 2005……………………………………….31

5. Hydrograph of freshwater flow of the Passaic River measured at Little Falls,

New Jersey, November 30 through December 13, 2005………………….32

6A. Salinity and water elevation, mooring 2, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom

(dotted) water…………………………………………………………………..33

6B. Bottom velocity at mooring 2, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom (dotted) water…………………………………………………………………………….34

6C. Bottom velocity at mooring 6, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom (dotted) water…35

6D. Surface-water turbidity and bottom-water OBS backscatter (in millivolts) measured at mooring 2, December 2, 2005………………………………..36

6E. Suspended sediment concentrations estimated from ADCP reflectance at mooring M1 and M2, December 2, 2005……………………………………37

7A. Concentrations of PCBs measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the New

Jersey NJCARP program……………………………………………………..44

7B. Concentrations of total PCDD plus PCDF measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the

2004 cores an the New Jersey NJCARP program…………………………45

4



Figures – continued

7C. Concentrations of 2,3,7,8-TCDD measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the

New Jersey NJCARP program……………………………………………….46

7D. Concentrations of 2,3,7,8-TCDF measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the 2004 cores an the New Jersey NJCARP program…………………………………………..47

7E. Concentrations measured in the Pilot Dredge program and the corresponding range of concentrations in bed sediment from the 2004 cores and from the

New Jersey NJCARP sampling conducted from 2000 to 2002…………..48

7F. Concentrations of mercury measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the New

Jersey NJCARP program conducted from 2000 to 2002………………….49

7G. Concentrations of lead measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the 2004 cores and the New

Jersey NJCARP program conducted from 2000 to 2002………………….50

8. Percentage of polychlorinated biphenyl (PCB) homologs by weight for pilot dredge background samples, bed sediment samples from 2004 core C, and New Jersey NJCARP samples of suspended sediment from the

Passaic River collected from 2000 to 2002…………………………………52

9. Flow and sediment imbalance calculated for the Lower Passaic River, mooring line M12 to M56, New Jersey, December 2, 2005…………………………75

10A. Concentrations of suspended sediment in cross-sectional composite samples collected from the Lower Passaic River, New Jersey, December

5, 2000. Vertical lines delineate intervals when chemical samples were collected………………………………………………………………………...86

10B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at mooring M12, Lower Passaic River, New Jersey, December 5, 2005…..87

5




10C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at mooring M56, Lower Passaic River, New Jersey, December 5, 2005…..88

10D. Salinity and water elevation at mooring 6, Lower Passaic River, New

Jersey, December 5, 2005……………………………………………………89

10E. East-west velocity measured at mooring 2, Lower Passaic River, New

Jersey, December 5, 2005……………………………………………………89

10F and 10G. Comparison of turbidity in the surface water, and optical backscatter (in millivolts) the bottom water at mooring 6, Lower Passaic

River, New Jersey, during the low tide at 17:45 on December 5, 2005, and the low tide at 5:40, December 6, 2006……………………………………..90

10H. Comparison of turbidity in the surface water at mooring 5, Lower Passaic

River, New Jersey, during the low tide at 17:45 on December 5, 2005, and the low tide at 5:40, December 6, 2005……………………………………..91

11A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December 6, 2005. Vertical lines delineate intervals when chemical samples were collected……….103

11B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M12, Lower Passaic River, New Jersey, December 6, 2005……….104

11C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 6, 2005………105

11D. Salinity and water elevation at mooring 2, Lower Passaic River, New

Jersey, December 6, 2005………………………………………………….106

11E. Salinity and water elevation at mooring 6, Lower Passaic River, New

Jersey, December 6, 2005………………………………………………….107

11F. East-west velocity measured at mooring 2 and mooring 6, Lower Passaic

River, New Jersey, on December 6, 2005…………………………………108

6




11G and 11H. Comparison of turbidity in the surface water, and optical backscatter (in millivolts) in the bottom water at mooring 6, Lower Passaic

River, New Jersey, during the low tide at 19:10 on December 6, 2005, and the low tide at 6:50 on December 7, 2005………………………………..109

Figure 11I. Percentage of polychlorinated biphenyl (PCB) homologs by weight for pilot dredge background samples collected December 6, 2005, and bed sediment samples from 2004 core C (0 to 1 ft.) from the Lower Passaic

River, New Jersey……………………………………………………………110


12B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M12, Lower Passaic River, New Jersey, December 7, 2005………120

12C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 7, 2005……….120

12D. Water elevation and salinity at mooring 2, Lower Passaic River, New

Jersey, December 7, 2005………………………………………………….121

12E. East-west velocity at mooring 2, Lower Passaic River, New Jersey,

December 7, 2005……………………………………………………………121

12F and 12G. Comparison of turbidity in the surface water, and OBS backscatter

(in millivolts) in bottom water at mooring 2, Lower Passaic River, New

Jersey, during the high tide at 12:15 on December 7, 2005, and the high tide at 1:40 on December 8, 2005………………………………………….122

12H and 12I. Comparison of turbidity OBS backscatter (in millivolts) in bottom water at mooring 1, Lower Passaic River, New Jersey, during the high tide at 12:15 on December 7, 2005 and the high tide at 1:40 on December 8,

2005……………………………………………………………………………123

7





13B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M1, Lower Passaic River, New Jersey, December 8, 2005………..131

13C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 8, 2005………132


Jersey, December 8, 2005…………………………………………………..133

13E. East–west velocity measured at mooring 2, Lower Passaic River, New

Jersey, December 8, 2005………………………………………………….134



Jersey, during the high tide at 12:15 on December 7, 2005, and the high tide at 1:40 on December 8, 2005………………………………………….135

14A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December 10, 2005. Vertical lines delineate intervals when chemical samples were collected……..145

14B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M12, Lower Passaic River, New Jersey, December 10, 2005…….146

14C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 10, 2005……..147


Jersey, December 10, 2005………………………………………………..148

8




14E. East –west velocity measured at mooring 2, Lower Passaic River, New

Jersey, December 10, 2005………………………………………………..149



Jersey, during the low tide at 10:30 on December 10, 2005 and the high tide at 22:40 on December 10, 2005………………………………………150

14H. Comparison of turbidity in the surface water at mooring 5, Lower Passaic

River, New Jersey, during the low tide at 10:30 on December 10, 2005, and 22:40 on December 10, 2005………………………………………….151

14I and 14J. Comparison of turbidity in the surface water, and bottom water OBS backscatter (in millivolts) at mooring 2, Lower Passaic River, New Jersey, during the high tide at 15:45 on December 10, 2005, and the high tide at

4:45 on December 11, 2005………………………………………………..152

14K. Comparison of turbidity in the surface water at mooring 1, Lower Passaic

River, New Jersey, during the high tide at 15:45 on December 10, 2005, and the high tide at 4:45 on December 11, 2005…………………………153

9



Tables

Table 1. Volumes of water processed and sediment captured in samples collected during the Pilot Dredge Program, Lower Passaic River, Newark

New Jersey, December 1 to 12, 2005……………………………………….19

2. Sample-specific detection limits for selected compounds in samples collected during the Pilot Dredge program, Lower Passaic River, Newark, New

Jersey, December 1 to 12, 2005……………………………………………..20

3. Equations used to estimate suspended sediment concentrations from moored acoustic Doppler current profiler reflectance data, Lower Passaic River,

Newark, New Jersey, December 1 to 12, 2005…………………………….41

4. Concentrations of selected constituents in samples of suspended sediment, collected during the Pilot Dredge study, Lower Passaic River, New Jersey,

December, 2005……………………………………………………………….57

5. Concentrations of selected constituents in bed sediment cores, collected during the 2004 coring program in the Lower Passaic River, New Jersey, and in samples from the New Jersey NJCARP Program, 2000-02………61

6. Concentrations of selected constituents in water samples collected during the

Pilot Dredge operations, Lower Passaic River, New Jersey, 2005……....64

7. Concentrations and concentration ratios of selected PCB congeners in sediment samples collected during the Pilot Dredge operations and in samples of bed sediment from the dredge area, Lower Passaic River, New

Jersey, 2005……………………………………………………………………67

8. Summary of sediment mass and loads and change in flow, Lower Passaic

River, New Jersey, December 2, 2005……………………………………...70

9. Net downriver load of sediment calculated to pass mooring line M12 during background days, Lower Passaic River, New Jersey, December 2-11,

2005……………………………………………………………………………74

10. Summary of sediment mass and doads and change in flow, Lower Passaic

River, New Jersey, December 5, 2005……………………………………..84

11. Summary of discharge and sediment mass and loads, Lower Passaic River,

New Jersey, December 6, 2005……………………………………………………99

12. Summary of sediment mass and loads, Lower Passaic River, New Jersey,

December 7 2005………………………………………………………………….114

10



Tables – continued


December 8, 2005……………………………………………………………………127


December 10, 2005………………………………………………………………….139

15. Summary of sediment, river conditions, and chemistry measured on the

Lower Passaic River, New Jersey, during the Environmental Dredge Pilot

Program, December 5-10, 2005……………………………………………….160

11



Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Timothy P. Wilson, Ph.D.

U.S. Geological Survey

West Trenton, N.J.

Introduction

To monitor the Lower Passaic River for contamination released by dredging sediment, samples of river water were collected from cross-channel sections located upriver and downriver from the pilot-dredge operations. These samples were analyzed for concentrations of suspended sediment (SS) and selected organic and inorganic compounds. The results were evaluated in combination with in-situ flow and turbidity measurements made by instruments at four moorings surrounding the dredge area.

Sampling and analytical methods are detailed in the Final Project Plans for

Environmental Dredging Pilot Study, November 21, 2005, prepared for the Lower

Passaic River Investigation and Feasibility Study under New Jersey Department of

Transportation (NJDOT) Task Order #OMR-03-3. In this report, the cross-channel monitoring data collected during the Lower Passaic River Environmental Dredging Pilot

Program, December 1-12, 2005, are evaluated.

A principal question addressed by the monitoring program design was “Did the pilot dredging, under the specific river conditions at the time, release contaminated dredged sediments to the river?” The monitoring described in this report addressed this question by setting “far-field” boundaries located 300 meters upriver and downriver from the dredging operations. Daily monitoring and constituent data were subjected to detailed examination, to answer the following specific questions:

12



1.

How did the suspended sediment in the river, determined by the cross-channel sampling, vary during the time dredging occurred?

2.

Are the variations in the content of SS captured by the cross-channel sampling confirmed by the turbidity measured at the moorings?

3.

Can any observed increase in SS be related to dredging activity? In order for an increase in SS to be attributed to dredging, it must have occurred in the proper spatial and time relation– that is, increased SS must have occurred downflow from the dredge area during times when dredging was ongoing to be attributable to the dredge operations.

4.

Can observed variations in SS and turbidity of the river be explained by natural processes in the river, such as the movement of the saltwater interface and its associated turbidity zone?

5.

How did the concentrations of selected water-quality indicators (total polychlorinated biphenyls (total PCBs), 2,3,7,8-TCDD, sum of DDT isomers

(total DDT’s)) differ between samples collected upflow and downflow from the dredging? How does the chemistry of the SS captured during dredging compare with that of the bed sediment, with samples collected before dredging, and with other background samples collected from the Lower Passaic River?

To address these questions, the SS concentrations in the cross-channel monitoring samples were compared to the times of dredging and to the physical and chemical characteristics of the river. Additionally, sediment loads from upstream were compared with those from the downflow monitoring lines. Finally, the concentrations of selected water-quality indicator chemicals were compared for the two monitoring locations with the chemistry of bed sediment and to historic values of indicator chemicals in suspended sediment collected from the Lower Passaic River.

13



Terminology

The following terms are used to describe the location and direction of the river flow.

Line M12 identifies the cross section of the river starting at the south shore, through mooring 1 and mooring 2, to the north shore. Moorings 1and 2 are the UPRIVER sampling and monitoring locations.

Line M56 identifies the cross section of the river starting from the south shore, through moorings 5 and 6 to the north shore. Moorings 5 and 6 are the DOWNRIVER sampling and monitoring locations.

Because bi-directional flow occurs during tide cycles, upflow and downflow directions are used to describe locations in relation to the direction of the water flow.

UPFLOW describes the monitoring line where water enters the study area.

DOWNFLOW describes the monitoring line where water leaves the study area.

The study area, moorings, and cross-section sampling lines are shown on figure 1.

14



Up river

Average up river velocity = 20 cm/s

M2

~25 minutes to reach M12 from dredge

Dredge

M1

300 meters from

M12 to dredge

~13 minutes to reach

M56 from dredge

300 meters from dredge to M56

M6

M5

Average downriver velocity = 40 cm/s

Figure 1. Schematic diagram of mooring locations and water flow in the dredge area,

Harrison Reach of the Lower Passaic River, Newark New Jersey.

15



Overview of Methods

Complete details of the methods used for the chemical and sediment sampling are presented in the Final Project Plans for Environmental Dredging Pilot Study, November

21, 2005, prepared for the Lower Passaic River Investigation and Feasibility Study under

NJDOT Task Order #OMR-03-3. Many of the sampling methods used in this study were modeled after methods developed by the States of New Jersey and New York working under the Harbor Estuary Plan (HEP) and the New Jersey Contaminant Assessment and

Reduction Program (NJCARP), which is a comprehensive program to evaluate the condition of the tributaries, estuaries, and harbors of Newark and Raritan Bays and the adjoining Hudson River (New Jersey Department of Environmental Protection, 2001;

New York/ New Jersey Harbor Estuary Program Final Comprehensive Conservation and

Management Plan, 1996). Only a brief synopsis of the sampling methods used in the Pilot

Dredge Program is provided here.

Sampling

During the pilot dredge work on the Harrison Reach of the Passaic River, background samples of SS and water were collected on December 1, 2005, from the upriver line M12 and from the downriver line M56; background samples were collected again on

December 12 from line M12 (fig. 1)

1

. Sampling at these locations also was conducted during the dredge operations on Dec. 1, 7, and 8 (once per day) and Dec. 5, 6, and 10

(twice per day). Sampling for SS concentrations and for analysis for indicator chemicals was conducted continuously during daylight hours except for brief interruptions at lunch or for equipment breakdown. Beginning each half-hour during sample collection, boats moved slowly from the south shore (starting at the 6-ft water depth) toward the north shore, and then returned to the south shore. During these traverses, water was pumped through two lines into individual sample bottles for SS and particulate organic carbon,

(POC) or through the Trace Organic Platform Sampler (TOPS) samplers for trace organic

1

The sample collected Dec. 12, 2005, was labeled as a downstream sample (labeled TD); however, it was collected from line M12. A sample was not collected from line M56 on that date.

16


Not USGS Approved (Revised September 2006) compounds. The inlet lines were attached to a weight which kept the intakes at approximately 1 meter below the water surface during the outbound [south (S) to north

(N)] leg. On the return leg (N to S), with the help of a depth finder, the intake was kept approximately 1 meter above the bottom. The duration of each round-trip traverse was kept as constant as possible at 10 to 12 minutes.

The water and SS samples, collected by identical TOPS samplers and pumping equipment in both boats, represent width-integrated composite samples that provide average concentrations of SS across the channel for the entire duration of sampling.

Water was pumped up through a dedicated Teflon line and then through a pre-cleaned

(baked) canister glass-fiber filter (1 micron nominal pore size) that collected SS. The outlet from the canister filter was then split and a small portion pulled through a glassfiber flat filter (0.7 micron pore size) and then through two columns containing XAD-2 exchange resin, which is a poly-styrene resin designed to sequester dissolved organic compounds. The outlet water from the filters and XAD columns was collected in separate carboys, and the volume of the processed water in each carboy was measured using a graduated cylinder at the conclusion of the sampling. The sediment-laden filters and the

XAD columns were sent for analysis for PCBs, dioxin-furans, and organochlorine pesticides. Because the emphasis of this work was on suspended sediment, only a few columns from selected days were analyzed.

During each cross-river traverse discrete grab samples also were collected for SS and

POC content; one discrete sample was collected from the surface (from 1 meter below the water surface) on the outbound leg (S to N) and a second discrete sample of deeper water was collected (from 1 meter above the river bottom) on each inbound leg (N to S). These samples were collected by pumping water from an intake line into individual polypropylene bottles held in an automatic sampler. The samples provided the average cross-sectional SS and POC content in the surface and bottom water. Because they were collected concurrently with the TOPS composite sample, they also provided the mass of sediment captured on the TOPS filters -- a required input for converting the results of the laboratory analyses into concentrations. This inlet line also was used to collect composite

17


Not USGS Approved (Revised September 2006) samples for analysis for trace elements; samples were prepared by collecting approximately equal volume aliquots of river water on each leg of the traverse into two sample bottles. By splitting the pump outflow of this line, both unfiltered and filtered composite samples were collected.

An important consideration in this type of sampling, where results from different locations and times are to be compared, is that similar masses and volumes are processed in each sample so that similar lower detection levels are obtained from analytical methods. In this type of sampling, the mass of sediment collected on the filters is not known until well after sampling has ended, so volumes and pumping rates were chosen to increase the likelihood that sufficient masses of sediment were collected to allow the lowest possible detection level to be obtained in each sample. The masses and volumes that were ultimately processed in this study (table 1) were similar between all pairs of samples and were adequate to allow low-level resolution of the compounds of interest in all samples. A summary of the minimum, maximum, and average sample- specific detection limits for the general classes of compounds measured in this study is presented in table 2. Detection levels are sample and compound specific; that is, each sample and each compound (including each polychlorinated biphenyl (PCB) congener) has a unique level of detection that is based on the analytical methods, the measuring instrument, and the mass/volume in the sediment. The similar volumes and masses also show that consistent sampling methods were employed at both monitoring lines.

18



Table 1. Volumes of water processed and sediment captured in samples collected during the Pilot Dredge Program, Lower Passaic River, Newark, New Jersey,

December 1 to 12, 2005.

Sample identifier Date and time Volume of water filtered, in liters

TD-GFF-051201-1130

TU-GFF-051201-1130

TD-GFF-051205-0730

TU-GFF-051205-0730

TD-GFF-051205-1430

TU-GFF-051205-1430

TD-GFF-051206-0830

TU-GFF-051206-0830

Dec, 1, a.m.

Dec 1, a.m.

Dec. 5, a.m.

Dec 5, a.m.

Dec 5, p.m.

Dec. 5, p.m.

Dec 6, a.m.

Dec. 6, a.m.

TD-GFF-051206-1330

TU-GFF-051206-1330

TD-GFF-051207-0930

TU-GFF-051207-0930

Dec 6, p.m.

Dec. 6, p.m.

Dec 7, a.m.

Dec 7, a.m.

TD-GFF-051208-1030

TU-GFF-051208-1030

Dec, 8, a.m.

Dec. 8, a.m.

TD-GFF-051210-0730 Dec. 10, a.m.

TU-GFF-051210-0730 Dec. 10, a.m.

TD-GFF-051210-1230 Dec. 10, p.m.

TU-GFF-051210-1230 Dec. 10, p.m.

TD-GFF-051212-0900 Dec. 12, a.m.

235.5

251.3

408.3

195.2

295.3

221.7

323.8

209.1

158.0

109.3

309.1

261.3

225.5

154.9

231.8

143.2

148.3

346.6

305.4

8.95

9.03

6.33

3.44

8.46

9.07

10.1

9.29

5.48

9.92

8.62

Mass of sediment calculated to have been collected on filters, in grams

18.8

16.8

3.83

5.19

7.92

6.07

6.11

7.54

Volume of water passed through

XAD columns, in liters

19.5

16.9

26.8

18.7

25.3

25.9

20.0

19.3

10.5

14.0

33.2

19.2

16.9

10.5

22.8

10.2

19.0

22.7

26.9

19



Table 2. Sample-specific detection limits for selected compounds in samples collected during the Pilot Dredge program, Lower Passaic River, Newark, New Jersey, December

1 to 12, 2005.

[ pg/L, picograms per liter; ng/kg, nanograms per kilogram; ug/kg, micrograms per kilogram]

Constituent and phase

PCBs, dissolved

PCBs, sediment

Dioxin, dissolved

Dioxin, sediment

1

Pesticide, sediment

Total 4,4’-DDT, sediment

Total Toxaphene, sediment

Minimum Maximum Average Units

0.01

0.01

1.00

132

0.11

4.19 pg/L ng/kg

0.06 18.2 1.76 ng/kg

0.0001 0.82 0.086 μ g/kg

0.026 0.77 0.17

μ

38 197 116 g/kg g/kg

1

Total of all pesticides analyzed except toxaphene.

20



Calculation of Chemical Concentrations

Analytical results provided by the laboratory (for both dissolved and sediment-bound compounds) were in units of mass per sample, and required conversion to concentration before use

2

. For the dissolved phase, the mass of each compound recovered was divided by the volume processed through the XAD columns (table 1). To determine the sedimentbound concentrations, the mass of sediment trapped on the filters was calculated using the SS concentrations from the discrete cross-section traverse composite samples. This mass was used to normalize the mass of recovered compounds to provide concentration values.

To calculate the trapped mass of sediment, the total volume of water filtered was divided by the number of traverses (legs) resulting in the volume assumed filtered on each outgoing (S-N) and incoming (N-S) leg. Because pump rates and the cross-channel boat velocity were kept as constant as possible, this results in an approximate mean-volume per leg value. The volume per leg was then multiplied by the SS (or POC) concentration measured in each SS grab sample from the respective individual leg to obtain mass per traverse leg. These masses were then summed (for the legs when the TOPS was operated) to get the final mass in the processed water. Then, the concentration in mass per gram of sediment was calculated using:

Concentration (pg or ng per gram of sediment) = (mass of chemical recovered in filter, in ng or pg) * filter efficency / (mass of sediment calculated to have been in the filtered water, in grams)

During the NJCARP program, field tests determined the filter efficiency to be 90 percent

(confirming the manufacture’s specifications), which accounts for the potential loss (10 percent) of sediment by breakthrough of the filters. The canister and flat filters used in

2

At the time of report preparation, the PCB and pesticide data had not been checked by the U.S.

Environmental Protection Agency quality-assurance officer. Several problems with the data were being investigated, and as result, the concentrations reported and conclusions reached in this report are considered preliminary, and are subject to change.

21


Not USGS Approved (Revised September 2006) this monitoring work were identical to those used in the NJCARP program; therefore, a filter efficiency of 0.9 was used in calculating the concentrations in this study.

Before normalizing, the raw data were compared to the analyses of one glass-fiber (GFF) filter and XAD blanks to evaluate for potential bias caused by field and laboratory contamination. The field equipment blanks were produced by opening the foil packaging holding a GFF filter and opening the end-caps of two unused XAD columns, which were left opened during the time when the sample filters and columns were installed in the

TOPS samplers. The blanks were resealed, handled, and analyzed in the same manner as were the field samples. The raw data from the field blank are assumed to represent the field contamination expected on all days of sampling, along with any laboratory induced contamination. The raw data from the sample analyses were compared with the data from the analysis of the filter and column blanks to determine whether the results for any compound was (potentially) biased by field or laboratory contamination. Following the procedures developed by the New Jersey Contaminant and Sediment Reduction Program

(CARP) that were modeled after guidance in the U.S. Environmental Protection Agency

(EPA) dioxin analysis methods (U.S. Environmental Protection Agency, 1994), if any compound (PCB, dioxin/furan, or pesticide) was present in a sample at a value less than 3 times the value in the field blank, that compound was to be removed from the data. There were no compounds in any of the SS phase samples affected by the blank elimination procedure. For the dissolved PCB and dioxin/furan concentrations, a value of 3 times was used for PCBs and dioxin/furans, and a value of 5 times was used for the dissolved pesticides.

One important result from the NJCARP program was the determination of the analytical uncertainty associated with the laboratory methods. During the NJCARP program, the analytical laboratory made repeated analyses of the standard reference materials (SRM), which were dried bed sediment from the lower NY Harbor. The National Institute of

Standards SRM (# 1944) contained a full suite of compounds commonly found in the

Passaic River, including PCBs, dioxin/furans, organochlorine pesticides, and trace elements. Analytic accuracy and precision were calculated for individual compounds by

22


Not USGS Approved (Revised September 2006) repeated measurement of the sediment. Although the analytical laboratories used in the

NJCARP study were not those used in the Pilot Dredge study, both studies employed the same analytic methods for analysis of PCBs and dioxin/difurans. For the NJCARP program, an uncertainty of 10 to 15 percent was associated with the laboratory methods.

On this basis, the uncertainty in the analyses of this study was assumed to be 15 percent; values that differed by less than 15 percent were considered indistinguishable. The

NJCARP study, organochlorine pesticides (OCPs) were determined by a high-resolution mass-spectrometer method, whereas in this present study, OCPs were measured using gas chromatography with electron capture detection. Thus, the uncertainty for the OCPs in the Pilot Dredge study can differ substantially from 15 percent. The 15 percent uncertainty is not associated with error introduced in the sampling procedures because it has not yet been possible to collect samples in (at least) triplicate from a well-mixed

“standardized” water using TOPs.

Calculation of Flow and Sediment Load Mass Balance

The sediment loads required for the sediment mass-balance determination were calculated for the river between lines M12 and M56, using data obtained by the automatic

Doppler current profiler (ADCP) that were recorded at the four moorings surrounding the dredging (M1, 2, 5, and 6), along with instrument calibration data supplied by Rutgers, the State University of New Jersey (presented in the Final Report of the Pilot Dredge project). The loads were used to establish whether the mass of sediment moving across each mooring line increased during dredging. Sediment load is a function of the volumetric water flow and the SS concentration in the river. The ADCPs provided high frequency measurements and averaging of water velocity and acoustic reflectance at each moored site. Acoustic reflectance is a surrogate measure of the suspended sediment in the water column and, with proper calibration, can be used to estimate SS concentration as a function of position in the water column. ADCPs work by sending a ping of acoustic energy up through the water column, and recording the reflectance and other acoustic parameters in a series of “bins” of set thickness in the water column. These data can be

23


Not USGS Approved (Revised September 2006) recorded instantaneously or averaged over a set number of pings. The setup, operation, and calibration of the ADCPs are described elsewhere in the Final Project Report.

Sediment load was calculated by first establishing the volumetric flow that passed each sampling line. The flow was calculated using the east to west (EW) velocity (cm/sec) recorded in each bin sampled by the ADCPs. Velocity was converted to flow using

Q n

= (V n

* A n

) , where

Q n

= flow in bin n, in cubic meters per second;

V n

= velocity in bin n, in centimeters per second; and

A n

= cross sectional area of bin n, in square meters.

The cross sectional area for each ADCP bin was determined from the equipment setup

(distance from ADCP head to center of bin) and the cross-sectional topography taken from the bottom topography survey made by Rogers Survey, P.L.L.C. in 2005. Cross sections of the river at each mooring line with a few representative ADCP bins established for these calculations are shown in figure 2. Because the ADCP head is elevated by almost 1 meter above the river bottom, two additional bins were added to the

ADCP velocity data set; bin 0.5 with a center at one-half the distance of the ADCP head to the bottom, and bin 0.25 at a center height of one-quarter the distance of the ADCP head to the bottom. E-W velocities were assigned to these bins at 50 (bin 0.5) and 25 percent (bin 0.25) of the velocity in bin 1, which approximate an exponential decay in velocity as the river bottom is approached. Using the velocities, the flow was calculated and assigned to each bin, all bins were summed from the bottom to the water surface, and the total flow from each adjoining mooring was summed to get total cross-section volumetric flow for a 30-minute period

3

. The change in flow between line M12 and line

M56, in percent, was then calculated using

3

ADCPs at moorings 1 and 5 recorded the velocity and reflectance each half hour. ADCPs at M2 and M6 recorded values each minute. Therefore, the data from M2 and M6 were summed again to get 30-minute total flow. This total was then added to the flow at the respective adjoining moorings.

24



Percent change = (Q

M12

– Q

M56

)*100/(Q

M12

) , where

Q

M12

= flow measure at line M12, in liters per 30 minutes; and

Q

M56

=flow measured at line M56, in liters per 30 minutes.

Positive values indicate more water flowed past line M12 than M56, and negative values indicate more water flowed past line M56 than M12. Uncertainty in the water balance comes from (1) assuming the uppermost ADCP bin is filled with water, when in reality the water level may have only partially filled the bin; (2) error in the bin width and cross- sectional area assigned to the upper-most bins, (3) assuming the velocity measured at the

ADCP holds over the entire width of the river, (4) using only the E-W velocity, and (5) assuming the ADCPs were at a location where they sampled approximately the same percentage of cross-sectional flow. For this study, water imbalances less than 15 percent were assumed acceptable, and no attempt was made to “zero” the imbalances by changing bin areas and other parameters.

The sediment loads then were calculated using the flow and sediment concentrations inferred from ADCP reflectance using calibration equations (table 3). These equations were developed from concentrations of SS in samples that were collected concurrently with ADCP measurements made from other boats (L and M boats), and by using a boatmounted ADCP in the vicinity of the four moorings. The concentrations of SS in the lowest bin (bin 1) was assigned to the two bins added for flow calculation

25



0

-0.5

-1

-1.5

-2

-2.5

-3

-3.5

-4

-4.5

1.5

1

0.5

A

Bin

Bin areas for M2 data were calculated from point C (south shore) to B

M2

Bin B

Two additional bins (0.5 and

0.25) were added below ADCP head

Bin

Bins areas for M1 were calculated from point A

(north shore) to point B

Bin

Meters from south shore

M1

A

-1.5

-2

-2.5

-3

-3.5

-4

-4.5

1.5

1

C

0.5

B

0

M5

Bin areas for M5 data were calculated from point C (south shore) to B

-0.5

-1

Two additional bins

(0.5 and 0.25) were added below ADCP head

B

Bins areas for M6 data were calculated from point A (north shore) to point B

M6

A

Distance from south shore in meters

Figure 2. Cross-sectional profiles showing ADCP bin areas for (a) line M12 and (b) line M56; Harrison

Reach, Lower Passaic River, Newark, New Jersey, 2005.

26



(bins 0.5 and 0.25). The estimated SS concentration for each bin then was multiplied by the volumetric flow for the bin. The bin masses from the bottom to the surface of the water column were summed and those totals then were summed with the values for the associated moorings to get the sediment load in kilograms per 30-minute interval

3

. The percent change was calculated in the manner used for the flow calculations. Uncertainty in the sediment balance, as indicated by large percent imbalances, comes from the uncertainty in the flow values plus uncertainty in the values from the calibration curves.

For this study, sediment loads with imbalances of less than 25 percent were assumed to be equal. This is an arbitrary level of uncertainty and is not based on measurements or other testing of the procedure.

Background Conditions

Background conditions in the river provide a baseline for comparing and contrasting the conditions measured during the dredging. Background data were obtained from (1) moored instrument data (turbidity and ADCP) collected on December 2, 3, 4 and 11,

2005, days when barge traffic was minimal and dredging did not occur, (2) analysis of samples of suspended sediment collected on December 1 and 12, 2005, as part of this study, (3) analyses of bottom-sediment cores collected during June 2004, as part of the

Lower Passaic River Investigation and Feasibility Study, and (4) analyses of suspended- sediment samples collected for the New Jersey NJCARP program during 2000-02. Data collected by the moored instruments were available for only a part of December 1, 2005, and were not considered in this evaluation of background conditions. The compositional data for the bed sediment were obtained from cores collected in 2004 from five locations in the dredge area (fig. 3) (TAMS, May 2005). The sediment from these cores was collected and composited by 1-foot intervals from depths of 0-1ft, 1-2 ft., and 2-3ft. for each of the 5 transects (A to E). The NJCARP data used here were collected during 2000-

02 by Stevens Institute of Technology and the U.S. Geological Survey (Stevens Institute of Technology, 2005).

27



695600

695550

10-Dec

Dredge Locations

8-Dec 7-Dec

6-Dec 5-Dec Cell row 1

Cell row 2 Cell row 3

Sediment from cores were composited for each transect, at

3 depths (0-, 1-2, and 2-3 ft.)

695500

E1

A1

B1

C1

D1

695450

E2

695400 C2

B2 D2

A2

695350

Core and cell identifier

E3

D3

A3

B3 C3

695300

594150 594200 594250 594300 594350 594400

New Jersey State Plane Y-coordinate, in feet

594450 594500 594550

Figure 3. Location of the bed sediment cores and the dredging activity during the Pilot Program, Lower Passaic River, Newark, New

Jersey, 2005.

28



Salinity and Turbidity

With the exception of December 9, the program was undertaken during a period of normal tidal flow (fig. 4). During this period, freshwater flow was elevated but was receding after a precipitation event that occurred the previous week (fig. 5). By

December 11, the freshwater flow entering the estuary had decreased to near mean annual flow of 1,128 ft

3

/sec (cubic feet per second). The weather was clear, calm, and cold.

However, on Dec. 9, a snow and wind storm moved through the area and disrupted the tidal flow. Because of this, data from Dec. 9 were not considered for background evaluation. Inspection of the data revealed similar patterns in turbidity, salinity, and flow during December 2-4 and December 11; therefore, data from December 2, collected at moorings 1 and 2, were chosen to illustrate the relations between water elevation, surface and bottom water salinity, and the turbidity in the river.

Mean daily flow for Dec. 2 was 3,475 ft

3

/sec, approximately 3 times the mean average value; flow decreased steadily throughout the day (fig. 5). During each tidal cycle the water-surface level changed by about 1.5 to 1.75 meters, and was accompanied by large, rapid changes in bottom water salinity (fig. 6a). The salinity of the surface water changed during each tide cycle but only by about one-half the change observed in the bottom water. In the bottom water, the salinity change was sharp, followed by a steady plateau, before declining with the ebb-tide freshening. The maximum flow velocity ranged from

30 to 40 cm/s (centimeters per second) during upriver flow, and was 60 to 80 cm/s during downriver flow (fig. 6b). During times when flow velocities were increasing, the difference between the velocity of the bottom water and surface water typically was large; however, at other times velocities were similar throughout the water column. It is of interest that the velocity profile at the down-river mooring M6 differed from that at

M2 (fig. 6c). At M6 the surface water velocity reached about 100 cm/s, while the bottom water veleocity remained low, less than 20 cm/s. This difference is due to channel morphology and the presence of the turnpike bridge immediately dowriver of M6. These differences in velocity profiles have important implications in attempting to calculate short-term (several hours or less) water balances and loads of dissolved constituents. The

29


Not USGS Approved (Revised September 2006) flow direction in the Harrison Reach was dominantly east to west with an average ratio of

E-W to N-S velocity for the study period (Dec. 1 to 12) of 18.4 (at mooring 1). However, approaching low tide, the N-S flow component would increase (especially at M2 and M5) as water apparently drained from the south shore into the deeper channel.

30



1

0.5

HT

@9:25

HT @

22:45

HT

@10:24

HT @

23:10

HT

@ 11:55

HT @

0:35

HT @

12:15

HT @

1:42

HT @

13:26

HT @ 2:23

0

HT @

2:23

HT @

15:47

-0.5

-1

-1.5

LT @

4:05

12/4

LT @

16:50

LT @

5:03

LT

@17:45

Dredging

10:24 - 12:35

13:02- 19:03

12/5

-2

LT

@

5:40

LT @

19:12

Dredging

9:17-12:23

13:01 -16:19

17:37 - 18:48

12/6

LT @

6:49

LT @

19:48

Dredging

7:44-15:38

12/7

LT @

20:43

LT @

8:10

Dredging

9:20 - 13:27

12/8

LT @

21:49

12/9

LT @

10:32

Dredging

7:45-10:38

12:39-15:18

12/10

LOCAL TIME

Figure 4. Water elevation at mooring 2 and periods of dredge activity in the Lower Passaic River, December 4-10, 2005.

[Pink lines show elevation at time of dredging activity].

31



4,000

3,500

3,000

2,500

2,000

1,500

1,000

Mean Annual Discharge = 1,128 cubic feet per second

500

0

2E

+07

2E+

07

2E+

07

2E+

07

2E

+0

7

2E

+0

7

2E+

07

2E+

07

2E+

07

2E+

07

2E

+0

7

2E

+0

7

2E+

07

2E+

07

2E+

07

DATE

Figure 5. Hydrograph of freshwater flow of the Passaic River measured at Little Falls, New Jersey, November 30 through

December 13, 2005.

32



December 2 - Mooring 2 Salinity and Water Elevation

11

10

9

8

14

13

12

5

4

7

6

3

2

1

0

-1

-2

-3

LT

Flow up river

HT

Surface

Bottom

Water Elevation

LT

Flow up river

H

Figure 6A. Salinity and water elevation, mooring 2, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom (dotted) water.

33



December 2 AM Mooring 2 Velocity at Bottom and Surface 1meter

100

80

60

40

20

0

+ = East flow to Newark Bay

-20

-40

-= West flow upriver

-60

-80

Flow up-river to M12

LT

Bottom Bin

Surface 1m

HT

Flow up-river to M12

Local Time

Figure 6B. Bottom velocity at mooring 2, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom (dotted) water.

34



December 6 Mooring 6, East-West Velocity

100


80

60

40

20

0

-20

Mooring 5-6 DOWN FLOW of Dredge Area

-40

-60


-80

Bottom ADCP bin

Average ADCP bins < 1 meter below surface

Local time

Figure 6C. Bottom velocity at mooring 6, December 2, 2005. Arrows show times when elevated turbidity was detected in surface (solid) and bottom (dotted) water.

35



December 2 Moorings 1-2

300

250

200

150

100

Flow up river toward

M12

Surface Turbidity M2

Bottom OBS M2

Surface Turbidity M1

Flow up river towards M12

50

LT LT

HT HT

0

Local Time

Figure 6D. Surface-water turbidity and bottom-water OBS backscatter (in millivolts) measured at mooring 2,

December 2, 2005.

36



350

300

250

200

150

100

50

December 2 - M12- ADCP - SS Concentrations

Flow

Up-river toward moorings 1-2

Mooring 1 - bottom

Mooring 1 - average top 1 meter

Mooring 2 - bottom

Mooring 2 - average top 1 meter

Flow

Up-river toward moorings

1-2

0

Local Time

Figure 6E. Suspended sediment concentrations estimated from ADCP reflectance at mooring M1 and M2,

December 2, 2005.

37



Inspection of data on surface turbidity and bottom optical back scatter (OBS)

4

, a measure of turbidity, (fig. 6d) from mooring M1 showed repeating periods when elevated turbidity

“spikes” occurred during each day representing periods when the content of suspended sediment in the water column had increased sharply. Turbidity in the deeper water

(mooring 1) experienced the same increases in turbidity as the shallower sections of the channel (mooring 2).

Overlaying the times when turbidity was high or when it peaked onto the plot of salinity and water elevation (fig. 6a) (Note: the solid arrows on fig. 6A and 6B represent the times of increased turbidity at the surface, and dotted arrows indicate increases in the bottom water), and the plot of water velocity (fig. 6b) shows that an evident relation exists between the times of elevated turbidity, salinity change, and high water velocity. As described earlier, ADCP reflectance can be used to estimate the SS concentration in the vertical water column. The plot of SS calculated from ADCP reflectance in the bottom and surface water (fig. 6e) shows the repeating periods of increased suspended sediment, with concentrations estimated to be as high as 300 to 400 mg/L.

These plots show that a zone of high turbidity, associated with the saltwater interface, moved through the monitored area during each tide cycle. This natural turbid zone, which has been reported in the literature (see references in Schubel, 1968; Geyer, 1993;

Buchard and Baumert, 1998, Chant and Stoner, 2201), results from the change in water salinity, which causes silt-clay sized particles to flocculate in the water column. The migration of the saltwater interface also is associated with times of high water velocity, times when surficial bed sediment can erode and become suspended. The change in salinity also affects the settling velocity of particles moving between the surficial fresh water and the deeper seawater, which helps the “cloud” of flocculated and resuspended sediments remain in the water column. Inspection of the data from all background days showed the correlation between turbidity and salinity was strongest for the bottom water;

4

OBS, optical backscatter, is measured in volts and is related linearly to turbidity, in NTU units, and therefore, suspended-sediment concentration. The OBS values were not calibrated to provide standard NTU turbidity units. Turbidimeters recorded directly in NTU units.

38


Not USGS Approved (Revised September 2006) the correlation is weaker for the surface water because turbulence from winds, passing water craft, and other sources act to keep sediment in suspension. The lateral distance the saltwater interface migrates upstream in the river is affected by the flow of freshwater into the estuary, the tidal range, and other factors. The steady tidal conditions and declining input of freshwater (except on Dec. 9) allowed the saltwater interface to migrate completely through the dredge area on each tide cycle during the days of dredging.

The recognition of the natural variation in suspended sediment content associated with the migrating saltwater interface is important when evaluating the impacts of release by dredging. Increases in SS that, at first, may seem related to dredging can simply be the result of natural estuarine processes and tidal flow. Also, the presence of high, natural turbidity makes it difficult to detect sediment released from dredging– any released sediment may quickly become assimilated and lost when the natural background turbidity is elevated.

Background Chemistry

The background chemistry of the sediment in the dredge area was determined from samples collected pre- and post-dredging, and was compared to the data from cores collected in 2004 in the dredge area, and with samples collected by Steven Institute of

Technology during the New Jersey NJCARP program conducted by the New Jersey

Department of Environmental Protection in 2000-02. The bed sediment cores, collected from the dredging cells

5

(fig. 3), are described in the Final Data Summary and Evaluation

Report (TAMS, 2005). The locations of the cores and the location of the dredging bites

5 for each day of the pilot program are shown on figure 3. As mentioned previously

(footnote 2), at the time of the preparation of this report, the USEPA quality assurance review of the data set was not yet complete, and several concerns had been identified

5

Dredging cells are the square areas into which the dredge area was divided. A dredging bite is an individual drop of the dredge.

39


Not USGS Approved (Revised September 2006) with the analytic work. Thus, the results and conclusions reached in this report are considered preliminary and may be subject to change in the future.

The NJCARP study used equipment and analytical procedures nearly identical to those used in this study, including the use of Trace Organic Platform Samplers (TOPS) and isotope dilution, high-resolution mass spectrometry for low-level quantification of PCBs and dioxin/furans. The 2000-02 NJCARP sampling in the Lower Passaic River was conducted by personnel from Stevens Institute of Technology, who collected samples of river water from the site PAS-1, located at the abandoned barge on the south shore of the

Passaic River, almost directly at the southern terminus of line M56. Samples were collected over a 6-hour period using tubing placed into the river and buoyed to remain at

1 meter below the surface. Sampling also was performed at the north end of Newark Bay at two depths, 1 meter below the water surface (NB-1S) and 1 meter above the bottom

(NB-1D). The details of the NJCARP sampling, methods, and results can be found in the report by Stevens Institute of Technology (2005). Only the suspended sediment phase chemistry of the NJCARP data is evaluated in the report.

40



Table 3. Equations used to estimate suspended sediment concentrations from moored acoustic Doppler current profiler reflectance data, Lower

Passaic River, Newark, New Jersey, December 1 to 12, 2005.

[ SS, suspended sediment concentration; ABS, reflectance value].

Mooring Equation

1

M1

M2

SS = 10^(0.0387*((ABS-3.781)/0.998) - 2.083)

SS=10^(0.0387*((ABS-0.649)/1.031) - 2.083)

M5 SS= 10^(0.0387*((ABS-9.471)/0.904) - 2.083)

M6 SS = 10^(0.0387*((ABS-16.927)/0.927) - 2.083)

1

SS is in milligrams per liter, ABS is reflectance value in decibel.

41



Pre- and Post-Dredging Sediment Chemistry

A summary of the concentrations of total PCBs, total dioxin/difuran (PCDD/PCDF),

2,3,7,8-TCDD and 2,3,7,8-TCDF, and total 4,4’-DDT in samples of SS and water collected during this study is provided as table 4. A summary of the concentrations of organic and inorganic chemical compounds the bed sediment cores collected during

2004, and in samples from the Lower Passaic River collected during the NJCARP is provided as table 5. These data are presented graphically in figures 7A-G.

The constituents selected for evaluation are a small subset of all compounds measured in the Pilot Dredge study. The compounds analyzed for this study were selected on the basis of the known presence of high concentrations in the bed sediment and on their significance in risk-based assessment schemes. Because most of the PCBs and all of the

PCDD/PCDF compounds are strongly hydrophobic and are not likely to exchange from the sediment to the water phase if released in the water column, these compounds are good indicators for the presence of bed sediment resuspended in the water column . Total

PCDD and total PCDF values (the sum of the congeners) are less useful indicators because two congeners, OCDD and OCDF, are typically high in the river bed and suspended sediment, and the concentrations of these congeners greatly outweigh all other congers concentrations combined. Thus, a small percent change in the concentrations of either of these two congeners can substantially affect the total PCDD/PCDF values.

Small changes in the percentage of OCDD or OCDF values can be the result of natural variability or analytical uncertainty. Therefore, two individual congeners, 2,3,7,8-TCDD and 2,3,7,8-TCDF, are likely better indicator species than total PCDD+PCDF. Likewise, total concentration of organochlorine pesticides (OCPs) is not considered to be a reliable indicator because of the wide range of properties (such as hydrophobicity or solubility) exhibited by the numerous compounds that were included in the analyses. Therefore, the total 4,4’-DDT value (the sum of 4,4’-DDT, 4,4’-DDD and 4,4’-DDE) was selected as the indicator for the presence this group of compounds. The 4,4’-DDT values were affected by problems in the analytical scheme used in this study, however. The organochlorine-pesticides were analyzed using gas chromatography with electron capture

42


Not USGS Approved (Revised September 2006) detection (GC-ECD), which is not a specific detection procedure, especially in complex mixtures of chlorinated compounds such as exists in these sediments. Also, a number of interferences and other analytical problems were noted by the laboratory for these compounds. Therefore, the results and conclusions based on the OCP compounds are considered tenuous.

Total PCBs in the three background samples collected on Dec. 1 and Dec. 12 ranged from 877 to 1,000

μ g/kg. Total PCB concentrations in the two samples from Dec. 1, collected during a period of downriver flow, differed by 123

μ g/kg, which is equivalent to a 12 percent decrease from the upflow sample concentration, within the assumed uncertainty of the analysis

6

. The concentrations in the background samples fall within the range of the total PCB concentrations in the NJCARP data from PAS-1 and the two

Newark Bay samples, which ranged from 466 to 1,345

μ g/kg. These values show that there is a large range in total PCB concentrations for the Lower Passaic River. The range for PCB concentrations in the surface (0-1 ft depth) layer of the bed sediment in cores collected during 2004 is 1,450 to 2,000

μ g/kg; the average is 1,660

μ g/kg. These values for the bed sediment (the sediment most likely to be mobilized by river tidal flow and by dredging) are much greater than the total PCB concentrations in the background samples from the 2005 Pilot-Dredge study and are similar to the lowest values in the NJCARP data from PAS-1 and Newark Bay samples (fig. 7a). The samples of sediment collected in 2004 and buried deeper than 1 ft in the riverbed contained total PCB concentrations as great as 7,830

μ g/kg.

6

Differences in concentrations are calculated as difference = upflow – downflow concentrations. Percent change is calculated as percent change = (difference/upflow concentration) *100.

Negative values indicate a loss between upflow and downflow sampling lines.

43



9,000

A

8,000

7,000

6,000

5,000

4,000

3,000

2,000

Pilot dredge suspended sediment, December 1 to 12, 2005

0 to 1 feet below river bottom



NJ CARP Passaic River suspended sediment

1,000

0

0 2 4 6 data

7A. Concentrations of PCBs measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the New

Jersey CARP program conducted from 2000 to 2002.

44



100

90

B

50

40

30

20

80

70

60

Pilot dredge data, December 1 to 12, 2005

0 to 1 foot below river bottom




10

0

0 2 4 6

7B. Concentrations of total PCDD plus PCDF measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the 2004 cores an the New Jersey CARP program conducted from 2000 to 2002.

45



3,000

2,750

C

2,500

2,250

2,000

1,750

Pilot dredge suspended sediment data, December 1 to 12, 2005

0 to 1 foot below river bottom




1,500

1,250

1,000

750

500

250

0

0 2 4 6

7C. Concentrations of 2,3,7,8-TCDD measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the New Jersey CARP program conducted from 2000 to 2002.

46



1,000

900

800

D Pilot dredge suspended sediment data, December 1 to 12, 2005

0 to 1 foot below river bed

1 to 2 feet below river bed



400

300

200

100

700

600

500

0

0 2 4 6

7D. Concentrations of 2,3,7,8-TCDF measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the 2004 cores an the New Jersey CARP program conducted from 2000 to 2002.

47



450

400

350

300

250

200

150

100

50

E

Pilot dredge study, December 1 to 12, 2005





0

0.0

2.0

4.0

6.0

Figure 7E. Concentrations of total 4,4’-DDTs measured in the Pilot Dredge program and the corresponding range of concentrations in bed sediment from the 2004 cores and from the New Jersey CARP sampling conducted from 2000 to 2002.

48



10

8

6

14

F

12





NJ CARP suspended sediment data

4

2

0

0 2 4 6

7F. Concentrations of mercury measured in the Pilot Dredge program and the range of concentrations in bed sediment from the 2004 cores and the

New Jersey CARP program conducted from 2000 to 2002.

49



1,200

G

1,000





NJ CARP suspended sediment data

800

600

400

200

0

0 2 4 5

NJ CARP data

6

7G. Concentrations of lead measured in the Pilot Dredge program and the range of concentrations in the bed sediment from the 2004 cores and the

New Jersey CARP program conducted from 2000 to 2002.

50



A plot of the percentage of each PCB homolog (fig. 8) shows that the homolog distribution in the samples from the Pilot Dredge program differs only slightly from the congener distribution of the bed sediment (Core transect C in figure 3, 0-1, 1-2, and 2-3 foot depth) and both distributions are very similar to that in the PAS-1 suspended sediment samples. As expected, the homolog distribution in the background suspended sediment samples is most similar to the distribution in the 0-1 ft. depth sediment cores.

Sediment from deeper in the botton-sediment has a slightly higher percentages of penta- and tetra- (especially in the 2-3 ft depth), and slightly lower percentages of hexa- and hepta- congeners. However, the differences among homolog percentages in the various samples is very small and may be the result of differences in analytical methods, or more likely, because a slightly different congener suite was measured in the NJCARP study (a different number of individual congeners were sought in the NJCARP study). What ever the cause, the slight differences in homolog distribution among sample (fig. 8) indicates that it is unlikely that changes in homolog distribution in the suspended sediment can be used to indicate that dredged bottom-sediment were released to the water column.

The three background samples from the Pilot Dredge program have very similar individual congener concentrations, as well as the presence/absence of congeners that are in the surfacial (0-1ft) samples from the five bed sediment cores. In fact, all congeners present in the surface bed sediment also were present in the SS, thereby precluding the presence of a unique “tracer” PCB in the bed sediment. Upon inspection of the individual concentrations available, nine congeners found to be present at nearly 5 times or greater

(by weight) in the bed sediment than in background SS samples (collected December 1 and 12) (table 7). These congeners are PCB 16, 17, 21, 25, 34, 96, 107, 137, and 150.

Three other congeners are of special interest --PCB 11, which was identified in the

NJCARP work as a tracer of pigments, and PCBs 77 and 126, congeners that have the highest co-planar PCB toxic equivalency factors. The ratios of the concentrations of this suite of 12 congeners in the bed sediment to the concentrations in the background SS samples were much greater than 5 (some well over 15) for the 1-2 ft and 2-3 ft depths of

51



35

20

15

10

5

30

25

Core C

PAS-1 and Pilot

Dredge samples

Core C 0 to 1 ft

Core C 2 to 3 ft

TU Dec. 5

TD Dec. 12

Core C 1 to 2 ft

PAS -1 Average

TD Dec. 5

0

Mono Di Tri Tetra Penta Hexa

Homolog group

Hepta Octa Nona Deca

Figure 8. Percentage of polychlorinated biphenyl (PCB) homologs by weight for pilot dredge background samples, bed sediment samples from

2004 cores C, and New Jersey CARP samples of suspended sediment from the Passaic River collected from 2000 to 2002.

[PAS-1, Passic River CARP sample site; C, core transect C in figure 3; TU, upriver sample site; TD, downriver sample site].

52


Not USGS Approved (Revised September 2006) the cores (table 7). Thus, the presence of high concentrations of these congeners in the SS collected during dredging, relative to the three background samples, could indicate that deep (1-3 ft) bed sediment was released into the water column. Inspection of the PCB data for all samples collected during dredging showed that the ratios of the bed-sediment congener concentrations to the concentrations in background samples generally were near

1 (table 7), which is also the ratio of the total PCBs concentrations in the bed-sediment samples relative to background samples. If ratios greater than or equal to 1.5 are arbitrarily considered “elevated”, than ratios for samples *TU-051205-1430, TD-051206-

1330, *TD-051207-930, *TD-051208-1030, and TD-051210-7:30 could indicate a rise in concentrations occurred that could relate to bed sediment having been introduced into the water column (* indicates samples collected upflow from the dredging operations). Of these samples, the sample TD-GFF-051206-1330 shows the most consistently elevated ratios for all the selected congeners. However, the following were considered in the evaluation: (1) elevated congener ratios are not consistent across all 12 congeners, and (2) the ratios for the SS samples do not approach the high ratios for the bed sediment samples. Thus, there was no clear evidence that, during dredging, any of the concentrations of these 12 congeners became elevated in the suspended sediment above the concentrations in background samples. The author emphasizes that the concentrations of this suite of congeners in the samples collected during background sampling and during dredging fall within the range of their respective concentrations in the NJCARP samples.

Concentrations of 2,3,7,8-TCDD are known to be elevated in the bed sediment of the

Passaic River, and together with 2,3,7,8-TCDF, may serve as a tracer of bed sediment released to the river during dredging. Concentrations of total PCDD plus PCDF also were evaluated, but these values are less reliable than others because they are controlled by the very high concentrations of OCDD and OCDF congeners. The 2,3,7,8-TCDD concentrations in the sample collected downriver on Dec 1

7

and the sample collected during post-dredging on Dec. 12 were similar, 258 and 267 ng/kg, respectively, and the concentrations of 2,3,7,8-TCDF were 13 and 18 ng/kg, respectively. These 2,3,7,8-TCDD

7

Results for the upriver sample TU-051201-1130 were not provided by the laboratory.

53


Not USGS Approved (Revised September 2006) concentrations are nearly the same as the average for the PAS-1 samples (279 ng/kg); however, the range of values in the PAS-1 samples is large (25-437 ng/kg) (figs. 7b to

7d). Average concentrations of 2,3,7,8-TCDD in the surface and middle layers of the bed sediment (0-1 and 1-2 ft depths; 336 and 374 ng/kg) were higher than the concentrations in background samples. The ratio of 2,3,7,8-TCDD to the concentration of total TCDD compounds could be a useful indicator of contaminated Passaic River sediment. The ratios in the surface bed sediments (0-1 ft) from the 2004 core ranged from 0.66 to 0.89; similar ratios were determined for the 0-1, 1-2, and 2-3 ft. depths (table 5). The ratios of total TCDDs for background samples of SS collected Dec. 1 and Dec. 12 are 0.75 and

0.63, respectively, which are less than to within the range of ratios for the bed sediments.

The average 2,3,7,8-TCDF concentration was higher for the PAS-1 samples (244 ng/kg) than for the background monitoring samples, but again, the background samples are within but near the lower end of the large range of concentrations in the NJCARP samples (6.3-870 ng/kg). The concentrations of 2,3,7,8-TCDF in the Pilot Dredge background samples (13 and 18 ng/kg) were lower than average values for the bed sediment (table 5; figs. 7b to 7d).

Concentrations of total OCPs in the three background monitoring SS samples ranged from 411 to 709

μ g/kg

8

; however, concentrations of total OCPs are not reliable values for comparisons because different suites of compounds and different analytical methods were used in the various studies. The dominant OCP compound in the suspended sediment samples were 4,4-DDT and its degradation products (4,4’-DDD, 4,4’-DDE).

The concentrations of total 4,4-DDT (the sum of DDT, DDE, and DDD) ranged from 178 to 421

μ g/kg, most of which (40 to 86 percent) was 4,4’-DDD, followed by 4,4’-DDE and 4,4’-DDT. The concentrations of total 4,4’-DDT in the PAS-1 samples ranged from

58 to 153

μ g/kg (120

μ g/kg average), and concentrations in samples from Newark Bay were 50 to 120

μ g/kg. Values from both depths were lower than the background concentrations measured in this study (figure 7e). The average concentration of total 4,4’-

DDTs was 195

μ g/kg for the 0 to 1 ft section of the bottom cores, 105

μ g/kg for the 1to

8

Total OCP content was not compared throughout this report because different methods were used for analysis and different compounds were reported for some of the samples.

54



2 ft and 165

μ g/kg for the 2 to 3ft sections. Thus, it appears that the highest concentrations of 4,4’-DDT in these various data sets were present in the SS samples collected during the pilot dredge operations. As a result, bed sediment released during dredging would cause concentrations of total 4,4’-DDT in the SS load in the river to decline.

Total DDT’s in the PAS-1 samples were composed of approximately 50 percent 4,4’-

DDD and 25 percent each of 4,4’-DDE and 4,4’-DDT, nearly identical to the composition of samples collected during dredging. In SS from Newark Bay, the average composition of total 4,4’-DDT was 45 to 48 percent 4,4’-DDE, 37 to 40 percent 4,4’DDD, and 11to

17 percent 4,4’-DDT. On average, the total DDT in the bed sediment consisted of approximately 50 percent 4,4’-DDT, 40 percent 4,4’-DDD and 10 percent 4,4’-DDE, which is similar to the values in the background samples. Deeper in the bed sediment (2-3 ft), 4,4’-DDE becomes the dominant (up to 64 percent on average) compound.

Mercury (Hg) and lead (Pb) were measured only in selected samples that were collected during the Pilot Dredge operations. Concentrations in the SS were determined by the difference between the total (whole water) and the dissolved fraction concentrations, multiplied by the average SS concentration calculated for the composite water sample.

Concentrations of Hg and Pb in the two background samples of SS collected on Dec. 1 were 0.190 mg/kg and 0.285 mg/kg, respectively. These values are within or slightly greater than the range of Hg and Pb in SS reported by NJCARP for PAS-1 and Newark

Bay samples (0.427 to 3.37 mg/kg for Hg; 112 to 322 mg/kg for Pb).

Concentrations of dissolved organic species were measured in water samples collected on selected dates, with pairs of samples collected Dec.1 and Dec 6. (pm) (table 5). In the background samples collected Dec. 1 and 12, the concentrations of total dissolved PCBs ranged from 3,610 to 4,800 pg/L (picograms per liter). These values are within the range reported for the NJCARP samples from the Lower Passaic River and Newark Bay.

Dissolved PCDD/PCDF species were not measured in the NJ CARP program, so no comparison can be made for these compounds. Values for dissolved 2,3,7,8-TCDD and

55



2,3,7,8-TCDF were reported as estimated maximum possible concentrations because values were at or below the method detection level for the analysis. These concentrations were all less than 0.20 pg/L. Total 4,4’-DDT concentrations in the background samples ranged from 0.441 ng/L to 0.630 ng/L (nanograms per liter), which are within the range reported by NJCARP for PAS-1 and Newark Bay samples (0.34 to 1.69 ng/L of total

DDT, including the 2,2’-isomers of DDT, DDE, and DDD).

56



Table 4. Concentrations of selected constituents in samples of suspended sediment, collected during the Pilot Dredge study, Lower Passaic River, New Jersey, December,

2005.

1

[PCB, polychlorinated biphenyls; OCP, organochlorine pesticides; PCDD + PCDF, polychlorinated dibenzo-pdioxin and difurans; Hg, mercury; Pb, lead;

μ g/kg, micrograms per kilogram; ng/kg, nanograms per kilogram;

μ g/g, micrograms per gram; ng/g, nanograms per gram; %, percent; shaded values are percent]

Date and time

Sample identifier

Location of sample site in relation to dredge

Dominant flow direction

TU-GFF-051201-1130

TD-GFF-051201-1130

TD-GFF-051205-0730

Dec. 1, 1130

Dec. 1, 1130

TU-GFF-051205-0730 Dec. 5, 730

Upriver

Downriver

TU-GFF-051205-1430 Dec. 5, 1430 Upriver

TD-GFF-051205-1430 Dec. 5, 1430 Downriver













TD-GFF-051212-0900 Dec. 12, 900 Upriver

TD-GFF-051212-0730 Dec. 12, 730

Upriver

Dec. 5, 730 Downriver

1,000 -123 -- -- -- --

877

1,540

1,230

791

1,190

1,290

523

142

1,090

57




2005. -- Continued




1


TD-GFF-051205-0730

TD-GFF-051205-1430

TD-GFF-051206-0830

5

-- --

TD-GFF-051206-1330

TU-GFF-051207-0930

TU-GFF-051208-1030

TD-GFF-051210-0730

TU-GFF-051210-1230

TD-GFF-051212-0730 -- -- -- -- -- -- --


2005. -- Continued

58







TD-GFF-051205-0730

TD-GFF-051205-1430

TD-GFF-051206-1330

TU-GFF-051207-0930

TU-GFF-051208-1030

TD-GFF-051210-0730

TU-GFF-051210-1230

374 --

59



1. Samples beginning with TU were collected from upriver line M12. Samples beginning with TD were collected from the downriver line M56.

2.Negative differences indicate loss from upflow to downflow sample, + values indicate increase .

Percent difference calculated as (delta concentration/upflow concentration) *100

3.Total OCP value does not include toxaphene.

4. Total 4,4’-DDTs value is the sum of 4,4’-DDD, 4,4’-DDE, and 4,4’-DDT concentrations.

5. Concentration of 4,4’-DDT not reported for this sample: total could not be calculated.

60



Table 5. Concentrations of selected constituents in bed sediment cores, collected during the 2004 coring program in the Lower Passaic River, New Jersey, and in samples from the

New Jersey CARP Program, 2000-02.

1

[PCBs, polychlorinated biphenyls; PCDD + PCDF, polychlorinated dibenzo-p-dioxin and difurans; Hg, mercury; Pb, lead;

μ g/kg, micrograms per kilogram; ng/kg, nanograms per kilogram; mg/kg, milligrams per kilogram; nd, not determined]

Sample site

Bed sediment – 2004 cores

5.9-14

Range

CARP DATA

2

5.6-28 36-92 .63-.79 70-143

5,510-7,830 5.0-23 300-1,600 20-120 .77-.84 116-241

NJCARP Suspended Sediment nd

Range

Station nd

Range

Range 466-966 0.9-12.9 5.8-210 4-59 nd

50-79

1. New Jersey CARP (Contaminant Assessment and Reduction Program) data provided by Joel Pechiolli, N. J.

Department of Environmental Protection, 2006.

2. Total 4,4’-DDTs is the sum of 4,4’-DDD, 4,4’-DDE, and 4,4’-DDT concentrations.

61





1

- - Continued.

[PCBs, polychlorinated biphenyls; PCDD + PCDF, polychlorinated dibenzo-p-dioxin and difurans; Hg, mercury; Pb, lead;

μ g/kg, nanograms per gram; ng/kg, picograms per gram; mg/kg, milligrams per kilogram; nd, not determined]

Sample

0-1 ft depth

1-2 ft depth

2-3 ft depth

Range

CARP DATA

2

Station PAS-1

Station NB-1S Shallow

Station NB-1D Deep

Range

3.9-7.5

1.2-3.1

Bed sediment – 2004 cores

260-307

437-477

570-760

NJ CARP Suspended Sediment

144-234

154-322

112-255

62





1

- - Continued.

[PCBs, polychlorinated biphenyls; Hg, mercury; Pb, lead;

μ g/kg, nanograms per gram; ng/kg, picograms per gram; mg/kg, milligrams per kilogram]

Sample

CARP DATA

2

Station PAS-1

NJ CARP Dissolved concentrations

.47-1.09

Station NB-1S Shallow

Station NB-1D Deep

0.54

.57

0.45

Range

Average Passaic River freshwater

.20-1.35 .34- .55 194-413

3. New Jersey CARP data provided by J. Pecchioli

4. total 4,4’-DDTs is the sum of 4,4’-DDD, 4,4’-DDE, and 4,4’-DDT concentrations

63



1

Table 6. Concentrations of selected constituents in water samples collected during the

Pilot Dredge operations, Lower Passaic River, New Jersey, 2005.

[PCB, polychlorinated biphenyls; OCP, organochlorine pesticides; PCDD + PCDF, polychlorinated dibenzop-dioxin and difurans; pg/L, picogram per liter; ng/L; nanogram per liter; %, percent; shaded values are percent; na, not analyzed; --, not applicable; * values are estimated maximum possible concentration]


Date and time

Location of sample site in relation to dredge

Dominant flow direction

TU-GFF-051201-1130 Dec. 1, 1130

TD-GFF-051201-1130 Dec. 1, 1130

TU-GFF-051205-0730 Dec. 5, 730

TD-GFF-051205-0730

Dec. 5, 730

Up 3,610 2.93

Down

Up

Down na -- na -- na --

TU-GFF-051205-1430

TD-GFF-051205-1430

TU-GFF-051206-0830 Dec. 6, 830

TD-GFF-051206-0830

TU-GFF-051206-1330

TD-GFF-051206-1330

Dec. 5, 1430

Dec. 5, 1430

Dec. 6, 830

Dec. 6, 1330

Dec. 6, 1330

TD-GFF-051207-0930 Dec. 7, 930

TU-GFF-051207-0930 Dec. 7, 930

TD-GFF-051208-1030 Dec. 8, 1030

TU-GFF-051208-1030 Dec. 8, 1030

TU-GFF-051210-0730 Dec. 10, 730

TD-GFF-051210-0730 Dec. 10, 730

Up

Down

Up

Down na na

--

-- na na

--

-- na na

Down

Up

Up 3,010 2.54

Down na -- na -- na

Down

Up

Up

Down na na

--

-- na na

--

-- na na

--

--

--

--

--

TD-GFF-051210-1230 Dec. 10, 1230 Down

TU-GFF-051210-1230 Dec. 10, 1230 Up na -- na -- na -- na -- na -- na --

TD-GFF-051212-0730

TD-GFF-051212-0900 Dec. 12, 900 Up -- 3,310 -- 1.13 0.11*

Dec. 12, 730 --

64



Table 6. Concentrations of selected constituents in samples collected during the Pilot

Dredge operations, Lower Passaic River, New Jersey – Continued.

[PCB, polychlorinated biphenyls; OCP, organochlorine pesticides; PCDD + PCDF, polychlorinated dibenzop-dioxin and difurans; pg/L, picogram per liter; ng/L; nanogram per liter; %, percent; shaded values are percent; na, not analyzed; --, not applicable; * values are estimated maximum possible concentration]

Sample na --

TD-GFF-051205-0730 na --

TD-GFF-051205-1430 na --

TD-GFF-051206-0830

TU-GFF-051206-1330 0.14

0.50 3.192 -1.118 0.624 -0.182

TD-GFF-051206-1330 na --

TU-GFF-051207-0930 na --

TU-GFF-051208-1030 na --

TD-GFF-051210-0730 na --

TU-GFF-051210-1230

TD-GFF-051212-0730 -- -- -- -- -- -- --

1. Samples beginning with TU were collected from upriver line M12. Samples beginning with TD were collected from the downriver line M56.

65



2.Negative difference indicate loss from up flow to down flow sample, + values indicate increase .

Percent difference calculated as (delta concentration/up flow concentration) *100.

3.Total OCP value does not include toxaphene.

4. Total 4,4’-DDTs value is the sum of 4,4’-DDD, 4,4’-DDE, and 4,4’-DDT concentrations.

66



Table 7. Concentrations and concentration ratios of selected PCB congeners in sediment samples collected during the Pilot Dredge operations and in samples of bed sediment from the dredge area, Lower Passaic River, New Jersey, 2005.

[PCB, polychlorinated biphenyl; concentrations are in nanograms per kilogram except total PCB, which is in micrograms per kilogram;

μ g/kg, micrograms per kilogram; ft., feet; BG, background value; ave, average]


Average BG

Average 0-1 ft

Average 1-2 ft

Average 2-3 ft

Ave 0-1ft / ave BG

Ave 1-2 ft / ave BG

Ave 2-3 ft/ ave BG

Concentrations

6,220 3,630 5,360 6,570 2,940 128 6,090 435 1,120 138 1,590 159

937

9,940 11,880 15,800 17,000 5,240 300 5,620 1,330 3,320 215 6,700 470 1,660

34,400 42,800 56,000 49,200 21,200 892 10,000 2,780 6,440 296 12,000 16,60 3,350

57,200 96,200 127,000 110,400 31,800 3,360 22,000 34,980 11,560 605 59,400 23,000 6,600

Ratios of concentrations

1.6 3.3 2.9 2.6 1.8 2.3 0.9 3.1 3.0 1.6 4.2 3.0 1.8

5.5 11.8 10.4 7.5 7.2 7.0 1.6 6.4 5.7 2.1 7.5 10.5 3.6

Sample/ average BG

TU-GFF-051205-0730

1

1.0 0.9 1.0 1.1 1.2 1.1 0.9 0.9 1.0 1.0 0.9 1.1 1.0

TD-GFF-051205-0730 0.8 0.8 0.8 0.8 0.8 0.8 0.5 0.5 0.5 0.4 0.4 0.5 .60

TU-GFF-051205-1430 1.5 1.6 1.5 1.7 1.5 1.5 1.3 1.6 1.6 1.7 1.5 1.7 1.7

TD-GFF-051205-1430 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.2 0.2 0.4 0.1 0.2 0.2

TD-GFF-051206-0830 1.3 1.3 1.4 1.4 1.5 1.5 0.9 1.1 1.1 1.0 0.9 1.3 1.2

TU-GFF-051206-0830 1.3 1.2 1.2 1.2 1.4 1.3 1.0 1.1 1.2 1.2 1.1 1.3 1.2

67



Table 7. Concentrations and concentration ratios of selected PCB congeners in sediment samples collected during the Pilot Dredge operations and in samples of bed sediment from the dredge area, Lower Passaic River, New Jersey, 2005. -- Continued.

[PCB, polychlorinated biphenyl; concentrations are in nanograms per kilogram except total PCB, which is in micrograms per kilogram;

μ g/kg, micrograms per kilogram; ft., feet; BG, background value]

Sample

Ratios of concentrations

1. For TU and TD samples, ratios are concentrations in the samples divided by the average concentration in the background samples.

68



Pre-dredging Sediment Load and Mass Balance

For the 9-day period beginning 00:00 on December 2 and ending on 00:00 on December

12, 2005,the overall difference (imbalance) in load between line M12 and line M56 was found to be -3.4 percent for water discharge, and -12.6 percent for SS; both are well within the assumed level of uncertainty.

The sediment loads and change in flow over 30-minute intervals and the 24-hour period of December 2 are shown in table 8. The calculated values were separated into periods of upriver and downriver flow. The 24-hour sediment imbalance (-4.2 percent) between lines M12 and M56 could be interpreted to represent the net bed sediment erosion

(26,400 kilograms or 1,100 kg/hr) from the area between lines M12 and M56. For the background days of December 2, 3, 4, and 11, the difference was slightly greater (1,781 kg/hr). It is entirely possible that these differences are the result of erosion of materials from the river bed, especially the channel edge. For example, erosion likely occurs from the south shore where depositional areas were obvious. This represents the natural transport, deposition, and erosion of sediment being carried by the river. The calculated differences are within the assumed uncertainty (25 percent), however, and the calculations were made for a 24-hour periods that includes partial tide cycles. If the calculations are made for less than a full tide cycle, then the difference between two monitoring lines will not include the SS mass returned during the next tide reversal.

The 24-hour period of December 2, the sediment imbalance of -4.2 percent represents a difference of 26,400 kilograms of sediment (table 8). The corresponding difference in water flow is -2.1 percent, so both the sediment load and water flow were in good balance. As the values in table 8 indicate, the 30-minute sediment and water flow imbalances differ dramatically over the successive time intervals, and can be quite large in some instances. When plotted (fig. 9), large imbalances occurred at three times during the day; this is typical of the other days of monitoring as well. Large positive differences in sediment loads are related to large

69



Table 8. Summary of sediment loads and change in flow, Lower Passaic

River, New Jersey, for December 2, 2005.

[kg, kilograms; M12, line M1 to M2; M56, line M5 to M6; totals are rounded]

Time, line

M12

0-30

30-100

100-130

130-200

200-230

230-300

300-330

330-400

400-430

Sediment load at line

M12, in

Kg/30 minutes

49,000

48,100

29,100

20,800

18,900

18,500

13,800

5,790

437

Time, line M56


M56, in kg/30

Difference, in Kg/30 minutes

Change in sediment load

1

, in percent

Change in flow percent

2

, in minutes

Flow downriver

30-100

36,400

100-130

26,300

130-200

24,100

200-230

27,500

230-300

24,600

300-300

14,000

330-400

4,120

400-430

-1,350

430-500

-5,030

500-530

-15,400

12,500 26

21,700 45

5,080 17

-6,650 -32

-5,620 -30

4,500 24

9,680 70

7,140 123

5,470 1,250

12,700 -475

17

30

17

0.6

24

40

67

138

1,290

-162

Total for 300 minutes

201,900

--

135,300 66,600 33 50

Flow upriver

81

50

33

-7.8

-100

-3,880

177

51

-79

Total for 270 minutes

-69,200

--

-64,200 -4,970 7.2 -32

70




River, New Jersey, for December 2, 2005 – continued.


Time, line

M12


M12, in kg/30 minutes

Time, line M56



Flow downriver

Difference kg/30 minutes


1

, in percent

Change in flow

2

, in percent

67,300 -12

54,900 8.7

53,200 11

54,600 13

39,500 25

37,500 18

30,600 27

1500-1530 27,500 1530-1600 23

17,000 39

5,370 75

Total for

570 minutes

456,000 -- 461,600 -5,240 -1.1 6.6

Flow upriver

-2,790 67

-7,620 33

Total for

210 minutes

-31,900

--

-47,600 15,700 -49 -24

71




River, New Jersey, for December 2, 2005 – continued.


Time, line

M12


M12 kg/30 minutes

Time, line M56


M56 kg/30 minutes

Flow downriver

Difference, kg/30 minutes


1

, in percent

Change in flow

2

, in percent

Total for

180 minutes

Total for 24 hours

72,200

628,000

97,000

654,000

-24,800

-26,400

-34

-4.2

-19

-2.1

1 Percent change in sediment mass is calculated as sediment mass at (M12-M56)*100/M12. Negative values indicate more mass calculated to have passed M56 than M12.

2 Percent change in flow is calculated as Q m12

-Q m56

* 100 / Q m12

, where Q is flow crossing mooring M12 or M56.

72


Not USGS Approved (Revised September 2006) negative differences in water flow across the two monitoring lines. The cause of these large imbalances in water is unclear at present; they are not always related to the times of highest and lowest tide but are more likely related to the times when the north-south flow velocity increased.

If sediment loads are to be compared over the short periods (1 tide cycle or less), then the travel time between mooring lines must be considered in the calculations. In the pilot dredge area, the average downriver flow velocity is approximately 40 cm/s over a tidal cycle, which corresponds to an average of 25 to 30 minute travel time for the 600 meters between line M12 to M56. During high tide, the average upriver velocity is about 20 cm/s, corresponding to an average travel time of 50 to 60 minutes from line M56 to line

M12. Therefore, when sediment mass balances are calculated for short periods of times

(partial tide cycles, such as during dredging), the loads must be offset 30 minutes for downriver flow and 60 minutes for upriver flow. Only when one-half, or a full, tide cycle is evaluated do these offsets strictly apply – different offsets should be used for calculating mass balances for less than one tide cycle.

The sediment-load data (table 8) were separated into the successive downflow and upflow periods of the tide cycle, as determined by the velocity measurement at M2, and the 30- or 60-minute offset was applied. The first downflow period has a large sediment imbalance (+33 percent), but this is the result of not using the entire period of downriver flow, which began shortly before 20:00 on December 1. Likewise, the imbalance for the last downflow period (2100 to 2330) is -34 percent, but again these calculations did not use the entire downriver flow which lasted until 4:45 on December 3. The one complete upflow period (500-930) and the complete downriver flow period (9:00 to 18:00) had very small imbalances for both sediment (7.2 and -1.1 percent, respectively) and water (-

32 and 6.6 percent, respectively). It was found that the SS calculated to cross one line, say line M12, during the complete upriver flow cycle (-69,200 kg per 270 minutes, or 256 kg per minute) does not equal the load carried downstream in the next successive downflow cycle (456,000 kg per 570 minutes, or 800 kg per minute). This inequality is

73


Not USGS Approved (Revised September 2006) due to the longer time periods of flow and to the differences in maximum velocity that was reached during the two tide cycles.

Net Sediment Load to Newark Bay

The net flux of SS that crossed either monitoring line is a measure of the amount of sediment delivered to the harbor from upstream sources minus the load brought back upriver by tidal action over a given time period. The net load (for a 24-hour period) across line M12 was quite large for the initial days, but decreased steadily until Dec. 4 when it decreased until Dec. 11 (table 9). The decrease was likely related to the decline in freshwater flow into the Lower Passaic River. The magnitude of these daily fluxes provides a base to compare with the mass of sediment dredged from the river bottom during this project.

Table 9. Net downriver load of sediment calculated to pass mooring line

M12 during background days, Lower Passaic River, New Jersey, December

2-11, 2005.

[kg, kilograms; hr, hours; m

3

/hr, cubic meters per hour; yd

3

/hr, cubic yards per hour; kg/m

3

, kilograms per cubic meter; values are rounded]

Date Flux

Dec. 2

Dec. 3 kg/24 hours

628,000

388,000

Flux kg/hr

26,200

16,200

Flux m

3

/hr

(dry weight

20.1

12.5

1

)

Flux yd

3

/hr

(dry weight)

26.3

16.4

Dec. 4 305,000 12,700 9.8 12.8

Dec. 11 61,000 2,540 2.0 2.55

1 Calculated using a bulk density of 1,300 kg/m

3 , which is the average bulk density in

2004 bed core samples.

74



500

400

300

200

100

0

-100

LT = low tide

HT = high tide

-200

LT

H

Discharge

Sediment LT HT

-300

0

100 200 300 40

0

500 600 700 80

0

900

100

0

110

0

120

0

130

Local Time

0

140

0

150

0

160

0

17

00

180

0

190

0

200

0

21

00

220

0

230

0

Figure 9. flow and sediment imbalance calculated for the Lower Passaic

River, mooring line M12 to M56, New Jersey, December 2, 2005.

75



Evaluation of Concentrations and Chemistry of Suspended

Sediment during Dredging

The SS concentrations, flow, data from moored instruments, and concentrations in suspended sediment were evaluated for each day of dredging to seek evidence of sediment release as a result of dredging. For each day, the following evaluations were undertaken.

1.

Concentrations of SS in the cross-channel monitoring samples were plotted to determine changes in SS during the periods of dredging.

2.

Turbidity (and OBS) measured by the moored instruments was plotted to confirm the change in SS observed in the cross-channel samples.

3.

The relations between the SS changes and the river characteristics (water level, salinity, and bottom currents) were established graphically to determine whether changes in SS were associated with the migration of the saltwater interface, and therefore, if they were related to the natural zone of maximum turbidity.

4.

For some days, the turbidity measured during dredging was compared with the turbidity measured during the next successive tidal cycle. This allowed a graphical comparison to be made to determine whether turbidity was elevated during dredging above a comparable level in the next (non-dredging) tide cycle.

5.

The SS loads were calculated (using data collected by the moored ADCPs) to determine whether SS load increased during downriver flow and periods of dredging.

6.

The differences in the chemical composition of SS collected upflow and downflow of the dredging were calculated for selected chemical species. The chemical data also were compared with chemical data for the bed sediment and with the range of values for the background data and for the NJCARP data from the Lower Passaic.

76



As discussed earlier, the chemical indicator species are a small subset of the entire set of chemical compounds that were measured in the samples and may not represent the changes measured for other specific chemical compounds. Also, review of the analytical results by the USEPA quality assurance/control was not yet completed at the time this report was prepared. Thus, values and conclusions are considered preliminary and are subject to change.

December 5

Dredging on December 5, 2005, was conducted between 10:24 and 12:35 (AM sampling), and 13:02 and 19:03 (p.m. sampling) (fig. 10A). A total of 25 unique dredge bites

9

were taken from between the NJSPC XY coordinates 561254-695381 and 594272-

695422 (corresponding dredge cell A2 fig. 3)

9

. During the morning dredging (10:40-

12:35) flow was downriver; however, sampling was conducted when flow was both upriver and downriver. For the morning, therefore, the line M56 was considered downflow. Cross-sectional sampling for SS was conducted from 8:00 to 12:30 (AM sampling). TOPS sampling was conducted from 8:30 to 12:00 at line M12, and 9:00 to

12:00 at line M56. During the morning, sampling was hampered by the freezing of the

TOPS equipment.

December 5-a.m.

Suspended Sediment

9

The number of bites represents unique bucket locations within a cell. Multiple bites may have been collected at a single location. Coordinates are given as X Y and are in the NJSPC coordinate system.

77



The reversal in flow during the morning makes interpretation of the SS and chemical data difficult. SS in the consecutive samples from the downriver (downflow) line M56 decreased steadily through the morning as dredging began (fig. 10A), whereas at the upriver (upflow) line M12 the concentrations increased steadily. At the upflow line M12, peak concentrations were reached between 11:30 and 12:30, but then decreased throughout the remainder of the day. Before 9:30, the flow of the river was upriver.

Because dredging started when flow was downriver (at 1024), the increase of SS in the upriver samples (line M12) cannot be attributed to dredging – flow is in the wrong direction to have affected samples from M12. The downflow samples from line M56 collected after 10:00 showed no increase in SS concentration that could be related to dredging.

Turbidity

No increase in water turbidity was observed in the surface water at M1 or the bottom at

M2 (fig. 10B) during the morning sampling; however, the turbidity in the surface at M2 increased starting at about 9:30. After peaking at 11:00, the turbidity decreased the remainder of the afternoon until about 16:00 after which the turbidity again increased.

Thus, suspended sediment in the surface water near M2 apparently caused the increase in the SS of the cross-channel SS samples. After 8:30, turbidity in the surface water at M1 was elevated, but was declining from the high values measured at 8:30. By the time dredging began, however, flow was downriver toward line M56, and the SS samples and turbidity showed no indication of a rise in SS until well after the dredging had ended (fig.

10C). Turbidity in the bottom water at M6 was slightly elevated but steady throughout the morning. A sharp but short-lived spike in the turbidity was measured in the surface water at downflow mooring M5 (after 12:00), however, the turbidity in the surface water at the downflow line M56 remained low and constant throughout the morning, consistent with the SS measured in the cross-channel samples. Apparently during this time, the dredge bucket seals were reported to be leaking, but repairs were made by 12:30. The spike in turbidity at M5 could be related to this malfunction.

78



Sediment Chemistry

The concentration of total PCBs decreased from 973

μ g/kg in the upflow sample (line

M12) to 523

μ g/kg in the downflow sample (line M56), a decrease of -46 percent.

Similarly, decreases were found in the concentrations of total PCDD+PCDF (-69%),

2,3,7,8-TCDD (-48%), 2,3,7,8-TCDF (-48%), total OCPs (-45%), and total 4,4’-DDTs (-

50%) (table 5). The rather constant decreases for all indicator components provide an indication that the SS was “diluted” by sediments having lower concentrations of these constituents (“cleaner” sediment). The concentrations of total PCB, PCDD+PCDF, and

4,4’-DDT in the monitoring samples were lower than those in the surficial (0-1 ft) bed sediment. The ratios of the concentrations of 2,3,7,8-TCDD to total TCDD were identical in the two samples 0.73, whithin the range reported for the surficial bed sediments (tables

5 and 6).

Concentrations of total PCB, 2,3,7,8-TCDD and 2,3,7,8-TCDF, and the total 4,4’-DDT are within the range of those in the NJCARP samples from PAS-1 and Newark Bay. Only the concentrations of total PCDD+PCDF in the upflow samples were higher than those reported by NJCARP for the SS. Concentrations of dissolved constituents were not determined for the samples collected in the morning.

December 5 – p.m.

The afternoon dredging began at 12:35 and ended at 18:00; during this time the flow direction was downriver until low tide was reached at 18:15. A total of 133 unique dredge bites were taken in the afternoon between the NJSPC XY coordinates 594278-695481

79


Not USGS Approved (Revised September 2006) and 594345-695465 (dredge cells B2 through E2, fig. 3). Cross-sectional monitoring for

SS was conducted from 14:00 to 17:00 (p.m. sampling) along lines M12 and M56.

During the afternoon, TOPS sampling was conducted on the upriver line M12 from 14:00 until 17:00, and on the downriver line M56 from 14:30 to 17:00.

Suspended Sediment

In the afternoon of December 5, the direction of water flow was from upriver (line M12) to the downriver (M56) moorings, making the interpretations of the data more straightforward than was the case for the morning data. The concentration of SS at the downriver line M56 increased during the afternoon, whereas the concentration of SS continued to decrease at the upflow line M12 (fig. 10A). The concentration of SS at the downriver line M56 began to rise at 13:30, approximately one-half hour after dredging began, and peaked in the surface and bottom samples collected between 15:30 and 16:00.

Turbidity

The turbidity in the bottom water downflow, measured by the OBS at moorings M5 and

M6, increased during the first hour of the afternoon dredging (fig. 10C). However, turbidity also increased in the bottom water during upflow at M1 and M2 (fig, 10B) and in the surface water at M1 during downflow, concurrent with the increase measured during downflow at M5 and M6.

One explanation for the increase in SS at downflow line M56, that the SS that moved upriver earlier in the day and was measured at line M12 moved downriver in the afternoon> Also, the increase in SS could be the result of downriver movement of the turbidity associated with the saltwater interface. High concentrations of SS were measured in samples of surface and bottom water at M12 as late as 13:00. Assuming an average downriver current velocity of 40 cm/s (beginning at 12:00), it would take approximately 25 minutes for water and sediment to move from the line M12 to M56; so the bulk of the sediment that had passed by line M12 should have passed M56 by mid-

80


Not USGS Approved (Revised September 2006) afternoon. This demonstrates the dynamic nature of the saltwater interface and its associated turbidity zone. The bottom water velocity during this period was slow, indicating that the saltwater interface remained in the dredge area during the afternoon.

As it slowly moved downriver, the SS and turbidity decreased at the upriver line (M12) and slowly increaseed at line M56. The author considers it important to note that as dredging proceeded during the afternoon, the concentration of SS decreased (after 15:00) at downflow line M56 in a manner similar to that observed at the upflow line M12. A decrease in concentration of SS in the downflow direction would not be expected if dredging was actively releasing bed sediment. The most likely explanation for the decrease in SS at line M56 during the afternoon was the return of the sediment cloud that had been located upriver earlier in the day.

Water Salinity and Velocity

The increase in suspended sediment and turbidity that was recorded at downflow mooring

M5, and (to a lesser extent) at the surface at M6 (fig. 10C) occurred between 14:00 and

16:00, the initial 2 hours of dredging. During this time, the salinity at mooring M6 was decreasing to freshwater values (fig. 10D). Thus, the increase in concentrations of SS and turbidity coincided with the movement of the saltwater interface downflow and the freshening of the river. At the same time, the flow velocity of the bottom water reached a maximum (50 cm/s) (fig. 10E).

Comparison of Turbidity during Consecutive Tide Cycles

Because the concentrations of SS increased downflow of the dredging during the afternoon, the turbidity values measured during the afternoon were compared with those measured during the next low tide cycle that occurred when dredging was not underway, in this case, during the low tide cycle in the early morning hours of Dec. 6. During the afternoon of Dec. 5, low tide was reached at 17:45 at M6, and on Dec. 6, low tide was reached at 5:40. To make the comparison meaningful, the data were shifted in time to

81


Not USGS Approved (Revised September 2006) line up with corresponding phases in each tide cycle. This was done by aligning the turbidity data with the time maximum low tide was first reached (fig. 10F, 10G, and

10H). The data were plotted for a period of 4 hours before until 4 hours after low tide.

Inspection of the turbidity in the surface water (fig. 10F) shows that two periods existed during the dredging when turbidity was elevated over the comparable time in the nondredging tidal cycle. The first was from 14:45 to 15:45, and the second began at about

16:30 and lasted until about 30 minutes before low tide. Except for these two periods, the patterns followed by the turbidity around the low tides are remarkably similar. The optical backscatter (OBS) values of the bottom water at M6 show that a period of elevated turbidity occurred about 4 hours before low tide and lasted for 2 hours (fig.

10G). Turbidity was also elevated in the surface water at M5, beginning more than 4 hours before and lasting until about 2 hours before the afternoon low tide was reached, compared with the turbidity during the next low tide cycle on the Dec. 6 (fig. 10H).

When presented in this manner, it is evident that periods of elevated SS, measured as turbidity, occurred downriver from the dredging.

Sediment Load and Mass Balance

The sediment load calculated using ADCP data from M12 and M56 were used to determine whether an increase in sediment load occurred during the afternoon dredging activities. The mass of sediment, in kilograms per each 30-minute interval, estimated for the two mooring locations are listed in table 10. The mass loads between M12 and M56 were offset for these calculations by 30 minutes to account for the travel time between moorings.

82



Inspection of the results for the 30-minute periods showed imbalances ranged from

-50 to +5 percent (Table 10). However, the difference for the period of downriver flow is

-23 percent, nearly identical to the 24-hour mass balance for Dec. 5. This difference is within the assumed uncertainty for this analysis.

83



Table 10. Summary of sediment mass and load, Lower Passaic River, New

Jersey, for December 5, 2005.

[kg, kilograms; tables are rounded]

Time at

M12 (upflow)

Mass of sediment passing M12, in kg/30 minutes

Time at

M56

(downflow)


1030 -1100 1,270 1100 -1130 3,260

1100-1130 1,410 3,910

1130-1200 2,020 4,670

1200-1230 2,620 5,830

1230-1300 5,030 9,200

1300-1330 6,460 19,100

1330-1400 14,600 22,600

1400-1430 21,900 30,400

1430-1500 25,100 40,300

1500-1530 30,800 29,000

1530-1600 23,300 21,500

1600-1630 17,800 16,100

1630-1700 13,300 13,100

1700-1730 11,100 8,930

1730-1800 8,700 4,840

1800-1830

5,370 1830-1900

Total

Total 24 hours

191,000

191,000

233,000

235,000

Difference in mass, in kg/30 minutes


1

,

in percent

-1,990 -157

-2,500 -178

-2,650 -131

-3,210 -123

-4,210 -84

-12,500 -192

-8,670 -62

-8,490 -39

-15,200 -60

1,790 5.8

1,830 7.8

1,700 9.5

291 2.2

2,140 19

3,900 45

-42,900

-44,700

1. Percent change in sediment load is calculated as sediment mass at (M12-M56)*100/M12. Negative values indicate more mass was calculated to have passed M56 than M12.

-23

-24

Sediment and Water Chemistry

The concentration of total PCBs (table 3) was 1,450

μ g/kg lower (91 percent decrease) in the downflow sample than the concentration measured in upflow sample (table 4). The concentration of total dioxin/furans decreased by 5.5

μ g/kg, a decrease of 32 percent. The concentration of 2,3,7,8-TCDD in the upflow samples was 49 percent lower than that in the downflow sample, however, the concentration of 2,3,7,8-TCDF in downflow samples was 43 percent greater. The concentrations of total 4-4’-DDT (sum of 4,4-DDD, DDE

84


Not USGS Approved (Revised September 2006) and DDT) in the upflow sample was 398 and was 121

μ g/kg in the downflow, a decrease of 70 percent.

In the upflow sample (line M12), the concentrations of total PCBs, and 2,3,7,8-TCDF were within the range of the concentrations in the surface layer of bed sediment (0-1 ft)

(table 5). The upflow sample was the only sediment sample with a 2,3,7,8-TCDD concentration similar to the concentrations in the deeper bed sediment. To some extent the concentration of 2,3,7,8-TCDF followed the same pattern (concentrations of up to

1,600 ng/kg were measured in the sediment collected from 2-3 ft in the river bottom).

However, this sample was collected upflow from the dredging, so its high concentration cannot be related to a release of dredged sediment. Rather, this demonstrates the large range of concentrations for this compound in the SS of the river. The ratio of the concentration of 2,3,7,8-TCDD to total tetra-TCDD in the upflow sample was 0.82, similar to the concentrations in the bed sediment. In the downflow sample, the concentrations of total PCBs and the other indicator compounds were lower than concentrations in the bed sediments, as was the ratio of the concentration of 2,3,7,8-

TCDD to total tetra TCDDs.

The upflow sample had concentrations of total PCB, total PCDD, 2,3,7,8-TCDD, and

4,4’-DDT that were higher than those reported for the river sediments by NJCARP for

PAS-1 and Newark Bay samples. The very high concentration of 2,3,7,8-TCDD mentioned earlier in the upflow sample indicates the range of 2,3,7,8-TCDD concentrations in suspended sediment is greater than that for the NJCARP samples. The concentration of 2,3,7,8-TCDF was within the range reported by NJCARP, but the total

PCBs concentration was lower than that for the NJCARP samples. All of the other indicator compounds were within the ranges reported by NJCARP.

85



120

100

80

60

Flow upriver to M12

Downriver line M56 shallow

Downriver line M56 deep

Upriver line M12 shallow

Upriver line M12 deep


40

20

Dredging Dredging

0

Local Time

Fig 10A. Concentrations of suspended sediment in cross-sectional composite samples collected from the Lower Passaic River, New Jersey,

December 5, 2000. Vertical lines delineate intervals when chemical samples were collected.

86



90

80

70

60

50

40

30

20

10

0

150

140

130

120

110

100

Flow upriver towards line

M12

Turbidity, mooring M2, surface

Backscatter, mooring M2, bottom


Backscater * 1000, mooring M1, bottom

Dredging


M12

Local Time

Figure 10B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at mooring M12, Lower Passaic River, New Jersey, December 5, 2005.

December 5 Mooring 5 and 6

150

140

130

120

110

100

90

80

70

60

50

40

30

20

10

0

LT

Flow upriver toward line

M12

HT

Turbidity, mooring M6, surface

Backscatter, mooring

M6, bottom

Turbidity, mooring M5, surface

Dredging LT

Flow up river toward line

M12

Local time

Figure 10C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at mooring M56, Lower Passaic River, New Jersey, December 5, 2005.

87



December 5- Mooring 6 Water Elevation and Salinity

8

6

4

2

12

10

Water elevation, mooring 6

Salinity, mooring 6, bottom

Salinity, mooring 6, surface

0

Dredging Dredging

-2

Local time

Figure 10D. Salinity and water elevation at mooring 6, Lower Passaic River, New Jersey,

December 5, 2005.

December 5 Mooring 2 E-W Velocity

100

80

+ = East flow to Newark Bay

Flow upriver to line

M12

Flow upriver to line

M12

20

0

-20

-40

60

40

Bottom ADCP bin

Average, ADCP bins

<1m from surface

-60

-= West flow upriver

-80

Dredging

HT

Dredging

LT

Local time

Figure 10E. East-west velocity measured at mooring 2, Lower Passaic River, New Jersey,

December 5, 2005.

88



December 5 Low Tide Mooring 6 Surface Turbidity

25

20

15

10

5

40

35

30

50

F

45

Low tide at 17:45 on Dec. 5


Flow upriver toward line M12

Low Tide @ 5:40 12/6

Low Tide @ 17:45

12/5

Dredging 10:24 through 19:03 12/5

14:45 15:45

16:45 Local time 12/5 18:45

Time before or after low tide

19:45

20:45 21:45

Mooring 6 December 5 Low Tide Bottom OBS Reflectance

100

90

G

50

40

30

20

10

0

80

70

60


Low tide at 17:45

Dec. 5

Low tide at 5:40,

Dec. 6

Low tide at 5:40 Dec. 6


Low tide at 17:45, Dec. 5


Figure 10F and 10G. Comparison of turbidity in the surface water, and optical backscatter

(in millivolts) the bottom water at mooring 6, Lower Passaic River, New Jersey, during the low tide at 17:45 on December 5, 2005, and the low tide at 5:40, December 6, 2006.

89



1000

H

December 5 Mooring 5 Low Tide Surface Turbidity



100

10




Dredging through 19:03, Dec. 5

1


10H. Comparison of turbidity in the surface water at mooring 5, Lower

Passaic River, New Jersey, during the low tide at 17:45 on December 5,

2005, and the low tide at 5:40, December 6, 2005.

90



December 6 – a.m.

Dredging on December 6 was conducted from 9:17 to 12:23 (AM sampling), from 13:01 to 16:19 (PM sampling), and for a short time from 17:37 to 18:48, which was not sampled. A total of 35 unique dredge bites were taken during the morning between the

XY coordinates 594244-695394 and 594281-695358 (corresponding to dredge cell A3)

(fig. 3). During most of the morning, flow was upriver toward line M12; however, the flow reversed (at 10:15) and was downriver for nearly half the time the dredging took place. Cross-sectional sampling for SS was conducted from 7:30 to 11:30 (AM sampling) along both lines. Sampling was conducted during both upriver and downriver flow.

TOPS sampling was conducted from 8:30 to 11:30 (PM sampling) along both lines; during most of this time flow was upriver. During the early morning, cold weather caused the equipment to freeze up, which may have affected the dissolved fraction samples.

Suspended Sediment

Flow during the morning of Dec. 6 was in both the upriver and downriver directions (fig.

11A), making interpretations of the SS and other constituent concentrations difficult.

Because most of samples were collected during upriver flow, the upriver line M12 is considered downflow for this evaluation (of the 10 transect samples collected, five were collected during the time dredging was underway). The concentrations of SS measured in the bottom water at the downflow line M12 peaked at 9:00, after which time the values steadily decreased. Concentrations of SS in the surface water at line M12 did not peak but rather decreased steadily throughout the morning- clearly the concentration of SS did not increase during dredging. A similar trend of decrease in concentration, was observed at the downriver line M56.

The highest concentration of SS in bottom-water samples during downriver flow (line

M12) was in the sample collected at 9:00, which was more than 15 minutes before the

91


Not USGS Approved (Revised September 2006) initiation of dredging. This peak was followed by a decline during the remainder of the morning. Thus, the spike observed in the bottom water at 9:00 cannot be attributed to a release from the dredging. Between 9:00 and 10:15, flow was upriver but was slowing as the tide began to reverse. At an average upriver velocity of -10 cm/s, sediment released from the dredge would take approximately 50-60 minutes to reach line M12. Thus, any sediment released early in the dredging activity could have reached line M12, and would be expected to be present in the samples. Any sediment released after the flow had reversed (after 10:15) would not have reached line M12 but could have reached line M56 before the end of sampling at 11:30. Clearly, there was no indication of an increase in concentration of SS during the dredging at either line M12 or M56.

Turbidity

The the OBS optical backscatter (turbidity surrogate) measured in the downflow bottom water at M1 (fig. 11B) increased during the morning, beginning around 8:00 and peaked at about 9:00 but then decreased during the remainder of the morning. A small increase in turbidity was detected in the bottom water at M2, and in the surface water at M2, beginning shortly after 9:00. The OBS values confirm the increase in SS measured in the bottom-water samples collected during the cross-channel monitoring at line M12. The increased turbidity in the surface water was not reflected in the concentrations of SS in the surface-water samples collected during the cross-sectional monitoring-- the increase in suspended sediment in the surface water may have been too small or localized to be detected in the cross-channel samples for SS. A large increase in turbidity was measured at moorings 5 and 6 beginning around 7:00, but turbidity had returned to low levels by

9:00, before dredging had started (fig. 11C); values remained low and constant in the surface and bottom water at M56 after 10:00. The turbidity measured at line M56 also confirms the concentrations of SS in the transect samples collected at this line.

92




The plot of salinity and water elevation at mooring M2 in figure 11D shows that the salinity of the bottom and surface water increased substantially beginning shortly after

8:00, reached a maximum at 10:00, and remained elevated throughout the afternoon. This confirms that the saltwater interface passed through the line M12 during the morning sampling. The dredging, however, occurred as the (upriver) flow velocity was decreasing

(fig. 11F), then through the period of stagnant flow at low tide, and continued as the flow downriver began to increase. The vertical velocity profile downriver is somewhat distorted – the velocity in the surface water remained low and steady from 10:00 until

13:00, then reversed. In the bottom water, the velocity peaked, then decreased and reversed until 14:00, after which time began to increase in the downriver direction.

Sediment Chemistry

The chemical concentrations in the suspended sediment collected the morning of

December 6 are difficult to interpret because sediment was collected during a flow reversal – there is no clear “upflow” to “downflow” relation between the sampling lines.

However, because most of the dredging occurred during the time of downriver flow, the samples from the downriver line M56 were chosen to represent downflow for this comparison.

The concentrations of total PCBs in the SS collected during the morning of December 6, decreased by just 7

μ g/kg, a 0.6 percent decrease between the sample collected upflow at line M12 and those collected downflow at line M56 (table 4). The concentration of total dioxin/furans in these samples decreased 1.8

μ g/kg, or 14 percent. The concentration of

2,3,7,8-TCDD decreased between the two monitoring lines (differing by -112 ug/kg or

43 percent), but the concentration of 2,3,7,8-TCDF increased slightly (14 percent). The concentration of total 4,4’-DDT increased by 35

μ g/kg (14 percent) between the two

93


Not USGS Approved (Revised September 2006) sampling lines. If the upriver line M12 had been chosen to represent the downflow sample, then all of these concentrations would have increased during the morning dredging.

Compared to the concentrations in the bed sediment from the 2004 cores, both afternoon samples contained lower concentrations of total PCBs and 2,3,7,8-TCDF, but both samples had concentrations of total PCDD+PCDF, 2,3,7,8-TCDD and 4,4’-DDTs that were within the ranges of concentrations for the bed sediment. Both samples had concentration ratios of 2,3,7,8-TCDD to total tetra-TCDD (0.67 and 0.76) that were within the range of ratios for bed sediment. Both samples had concentrations of total

PCBs, total PCDD+PCDF, 2,3,7,8-TCDD, and 2,3,7,8-TCDF that were within the range of concentrations for the NJCARP samples from PAS-1 and Newark Bay, but had a concentration of total 4,4’-DDT content that was higher than the concentrations range for the NJCARP samples. Concentrations of dissolved constituents were measured only in the down river (downflow) samples, so the change in chemistry could not be evaluated.

December 6 p.m.

Dredging in the afternoon of December 6 was conducted from 1301 to 1619 (PM sampling) and for a short time from 17:37 to 18:48, which was not sampled. During the afternoon dredging (13:01 to 16:19) 82 unique dredge bites were taken between the

NJSPC XY coordinates 594285-695362 and 594436-695390 (dredge cells B3 through

D3) (fig. 3). Flow was downriver toward line M56 during the entire afternoon. Crosssectional monitoring for SS was conducted from 13:30 to 16:00 along both lines. TOPS sampling was conducted from 13:30 to 16:00 along line M56 and from 13:30 to 16:30 along the upriver line M12.

94



Suspended Sediment

During the afternoon of December 6, the flow of the river was in one direction from line

M12 toward line M56. Concentrations of SS in samples from the upflow line M12 and the downflow line M56 increased steadily as dredging proceeded (fig. 11A), reaching very high values in both the bottom and surface water. The large concentrations of SS in the samples from M12 cannot be attributed to dredging; line M12 were upflow from the dredging area for the entire afternoon, and the flow had been downriver for nearly 2.5 hours after the morning dredge activities had ended.

Turbidity

Turbidity in the surface and bottom water downflow at mooring M56 (fig. 11B) had already started to increase before dredging commenced at 13:00. Although the turbidity data are extremely “noisy”, and temporal trends are difficult to discern, an extremely large spike in turbidity occurred in the surface water at mooring M6 after the start of dredging at 13:00 and lasting until 14:00 (fig. 11C). A second spike in turbidity at M6 was detected from 19:00 to 20:00, well after the evening dredging had ended. Turbidity

(and OBS backscatter) at M5 and M6 reached maximum values between 15:00 and 16:00 hours, after which it decreased. The decrease in turbidity continued well after the dredging had ended at 1619. At the upflow moorings M1 and M2, the turbidity in the bottom water (M2) and in the surface water (M1) also began to increase starting at about

15:00 (fig. 11B). The SS data from downflow mooring 5 and 6, as well as from upflow moorings 1 and 2, confirm the increase in turbidity observed at both cross-channel sediment sampling lines (fig. 11A).

The increase in concentrations of SS in samples collected along downflow line M56 can be explained by the downstream transport of sediment in the water measured concurrently at line M12 (fig. 11A). At an average downriver flow velocity of 40 cm/s, sediment passing line M12 would reach line M56 in about 25 to 30 minutes. Although the

95


Not USGS Approved (Revised September 2006) downriver transport of sediment contributed the high concentrations of SS at line M56, the concentrations in samples from line M56 were higher than those measured in samples collected at line M12 (at least until the 16:00 sample), indicating that additional sediment was added to the water between lines M12 and M56.


The salinity data (figs. 11D and 11E) shows that the water at both sampling lines M12 and M56 was very saline during the first half of the afternoon dredging period but freshened to nearly freshwater values by the time dredging ceased shortly after 16:00.

During this time, the velocity of the bottom and surface water increased rapidly and reached a maximum downriver flow rate of more than 60 cm/s by 15:00 (fig. 11F). Thus, the afternoon rise in concentration of SS occurred during the passing of the saltwater interface and during the times when maximum flow velocity was reached in the dredge area.


Because the SS increased downflow during the afternoon dredging on Dec. 6, the turbidity values were compared with the turbidity values during the next low tide cycle that occurred during the early morning hours of Dec.7 (when dredging was not underway). To make the comparison meaningful, the data were shifted in time to line up corresponding phases in the tide cycles. During the afternoon of Dec. 6, low tide was reached at 19:10 at M6, and on Dec. 7 at 6:50 (fig. 11H and 11I). To do this, data measured at line M56 were aligned on the time when maximum low tide was first reached (0 on the plot) and were plotted for a period of four hours before, until four hours after, low tide.

96



With two exceptions, the turbidity in the surface water at M56 was very similar during these two tide cycles (figs. 11G and 11H). The first difference occurred near the end of dredging at 16:10 on December 6, when the turbidity in the surface water increased to nearly 5 times the turbidity measured during the same relative point in the Dec. 7 low tide cycle (fig. 11G). The period of high turbidity lasted until approximately 30-45 minutes after the end of dredging. A rise in turbidity (OBS backscatter) also occurred about the same time in the bottom water at mooring 6 (fig. 11H). Thus, when compared with the conditions during the next low tide, the turbidity values at downflow line M56 indicated the suspended sediments in the water column had increased from earlier values.

A second very large increase in turbidity occurred in the surface water just as maximum low tide was reached at 19:10 on Dec 6 and lasted for more than 30 minutes (fig. 11G).

The increase occurred well after maximum low tide was reached and may have been associated with the dredging that occurred in the evening on Dec. 6 and ended at 18:48, some 25 minute before maximum low tide. Because the cross-channel monitoring had ended, this increase in turbidity was not captured by the SS or chemical sampling data.


The sediment load and mass data for the afternoon of December 6 are presented in table

11. The overall sediment mass balance beginning at 13:00 changed by -61 percent between the upflow and downflow lines, much higher than the level assumed to be significant. The difference between mass balances supports that sediment was released during the afternoon dredging.

97



Table 11. Summary of discharge and sediment mass and load, Lower Passaic River, New Jersey, December 6,

2005.

[kg, kilograms]

Time at

M12

(upflow)

Volume of water passing

M12, in cubic meters/30 minutes

Mass of sediment passing


Time at

M56 for

(downflow) mass was calculated to have passed M56 than M12.

Volume of water passing

M56, in cubic meters/30 minutes


Difference in mass

(M12-M56), in kg/30 minutes

Change in discharge

1 percent

, in


in percent

1300-1330

99,300

1330-1400

282,000

1400-1430

449,000

1430-1500

506,000

1500-1530

480,000

1530-1600

481,000

1600-1630

Total

426,000

2,730,000

Total 24 hours 4,700,000

958 1330-1400

381,000

4,600 1400-1430

515,000

8,920 1430-1500

583,000

18,600 1500-1530

531,000

3,310,000

5,320,000

7,800 -7,100

-280

16,700 -12,300

-83

23,100 -14,200

-30

26,300 -7,700

-5.0

26,700 -7,180

-5.0

34,700 -13,800

12

26,300 634

162,000 -61,300

15

-21

-710

-278

-159

-42

-37

-66

2.4

100,000

190,000 271,000 -80,400 -13

-61

-42

1. Percent change in discharge and sediment load are calculated as volume or sediment mass at (M12-M56)*100/M12. Negative values indicate more

1

,

98



Sediment Chemistry

The concentration of total PCBs in SS increased from 967

μ g/kg in the upflow sample collected at line M12 to 1,540

μ g/kg in the downflow sample collected downriver at line

M56, representing a 59 percent increase in the concentration (table 4). As shown in figure 11I, the homolog profile of the two samples are very similar, differing mainly in the slightly higher percentage of tri-homolog congeners in the downstream sample. The two samples are very similar to the surface layer of the bottom-sediment (0-1 ft.), and there is no indication in the suspended sediment profiles of the elevated penta-homolog proportion observed in the bottom-sediment. Any difference in the homolog compositions between upstream and down-stream samples, and any difference between homolog composition in the suspended sediment and bottom sediment, is likely within the range of scatter in the analysis.

Concentrations of total dioxin/furans were lower in the upflow than in the downflow samples, a decrease of 20 percent. The concentration of 2,3,7,8-TCDD increased by 103 ng/kg (33 percent) and the concentration of 2,3,7,8-TCDF decreased by 1 ng/kg, or a decrease of -5 percent. Changes in concentration of total 4,4’-DDTs could not be evaluated because a value was not reported by the laboratory for the upflow sample.

The concentration of total PCB in the upflow sample was lower than the concentrations reported for the surface bed sediment, but the concentration in the downflow sample was within the range for the bed sediment in this study. Likewise, concentrations of total

PCDD+PCDF, 2,3,7,8-TCDD, and total 4,4’-DDT in upflow and downflow samples were within the range of concentrations for the bed sediment, but the concentrations of

2,3,7,8-TCDF in both afternoon samples was lower than the range for bed sediment. The ratios of concentrations of 2,3,7,8-TCDD to total-tetra TCDDs for both samples were nearly identical (0.67 and 0.69) and within the range reported for bed sediment. The concentration of total PCBs in the upflow sample was within the range reported for the

NJCARP SS samples, but for the downflow sample the concentration was greater than

99


Not USGS Approved (Revised September 2006) the range reported by NJCARP. The concentration of total PCDD+PCDF in the upflow sample was greater than the range, but the concentration in the downflow sample was within the range reported by NJCARP. The concentrations of 2,3,7,8-TCDD, 2,3,7,8-

TCDF, and total 4,4’-DDT concentrations in both samples were within the ranges reported by NJCARP for PAS-1 and Newark Bay SS samples.

Water Chemistry and Mass Balance

Concentrations of dissolved constituents were measured in the upflow and downflow samples collected on the afternoon of Dec. 6. This was the only dredging day for which concentrations of dissolved constituents were obtained for both the upflow and downflow samples. The concentration of dissolved total PCBs increased 660 pg/L (picograms per liter)(18 percent), whereas the concentration of total PCDD+PCDF decreased 5.6 pg/L

(22 percent) from the upflow sample to the downflow sample. The concentration of

2,3,7,8-TCDD increased slightly in the upflow sample, although in the downflow sample this congener was below the detection level. The concentration of 2,3,7,8-TCDF was nearly the same in upflow and downflow samples, increasing only 7 percent. The concentration of dissolved total 4,4-DDT decreased 29 percent from the upflow to downflow sample. Values of all these indicator species are within the range reported for the NJCARP samples. Concentrations of all dissolved phase constituents were similar to the respective concentrations obtained during the background sampling on December 5.

The volumetric discharges for each 30 minute time period during the afternoon (table 11) show that during the afternoon roughly 580,000 cubic meters more water passed line

M56 than M12 (21 percent change). Although curious, this difference is due to the flow reversal that occurred from 12:30 to 13:00 – figure 11F shows the velocity of the water in the surface layer at M2 was increasing (down-river) while the water at the bottom of the channel was either still moving upstream, or was stagnant (no velocity). After about

13:30, a large difference (about 40 cm/sec) existed in water velocity of the surface and the bottom layers at M2. At the same time the profile at M6 shows that the velocity of the surface water was very similar to that at M2, but the bottom water velocity at M6 was much lower than at M2. These differences in velocity result in more water calculated to

100


Not USGS Approved (Revised September 2006) have passed M12 than M56. Removing the 30 minute time offset in the data used in table

11 results in a difference of 390,000 cubic meters of water, a change of 14 percent, which is still greater than the assumed error in this method (+/- 10 percent). Balances for shorter time periods (1 to 2 hours) are less than 5 percent. Multiplying the discharge that crossed each line for the entire afternoon period (table 11) by the respective concentrations of dissolved PCB (table 6; 3,010 pg/L and 3,670 pg/L, respectively) showed that approximately 8 grams of PCB passed line M12 and 12 g of PCB passed line

M56 during this time. This difference (50%) is a product of the differences in water volumes and differences in concentrations. Any balance developed for dissolved chemicals can be no more accurate than the balance developed for water plus the uncertainty in the analytic concentrations. The large difference in estimated discharge crossing the two lines makes evaluating the cause of the difference in PCB (or other chemical) load tenuous.

101



60

50

40

30

90

80

70

130

120

110

100


Downriver line M56 shallow

Downriver line M56 deep

Upriver line M12 shallow

Upriver line M12 deep

20

Dredging

10

Dredging

0

700 730 800 830 900 930 1000 1030 1100 1130 1200 1230 1300 1330 1400 1430 1500 1530 1600 1630 1700

Local time

Fig 11A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December 6,

2005. Vertical lines delineate intervals when chemical samples were collected.

102



110

100

90

80

70

60

50

40

30

20

10

0

150

140

130

120

Turbidity mooring mooring M2 surface

Backscater mooring M2 bottom

Turbidity mooring M1 surface

Backscater * 1000 mooring M1 bottom


M12

2 points off scale

Dredging


M12

Local time

Figure 11B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M12, Lower Passaic River, New Jersey, December 6, 2005 .

December 6 Mooring 5-6 Surface Turbidity and Bottom OBS Reflectance

1000

100

10

1


Backscatter, mooring

M6, bottom


Backscatter, mooring

M5, bottom

LT


HT

Dredging

Local time

LT

Flow upriver toward line

M12

103



Figure 11C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 6, 2005.

104



December 6 Mooring 2 Salinity and Water Elevation

4

3

2

1

7

6

5

0

-1

-2

12

11

10

9

8

Dredging

Dredging

Water elevation

Salinity, mooring 2, bottom

Salinity, mooring 2, surface

Dredging

Local time

Figure 11D. Salinity and water elevation at mooring 2, Lower Passaic River, New Jersey,

December 6, 2005.

12

11

10

9

8

7

6

5

4

3

2

1

0

105



December 5- Mooring 6 Water Elevation and Salinity

8

6

4

2

12

10

Water elevation, mooring 6

Salinity, mooring 6, bottom

Salinity, mooring 6, surface

0


-2

Local time

Figure 11E. Salinity and water elevation at mooring 6, Lower Passaic River, New

Jersey, December 6, 2005.

106




100


80

60

40

20

0

-20

-40

-60

-80


Flow upriver

to line M12

Dredging

Bottom ADCP bin

Average ADCP bins <1 meter from surface

Dredging

Flow upriver to line M12

Local time

December 6 Mooring 6, East-West Velocity

100


80

60

40

20

0

-20

Mooring 5-6 DOWN FLOW of Dredge Area

-40

-60


-80

Dredging

Bottom ADCP bin

Average ADCP bins < 1 meter below surface

Dredging

Local time

Figure 11F. East-west velocity measured at mooring 2 and mooring 6,

Lower Passaic River, New Jersey, on December 6, 2005.

107




10,000

G Flow is upriver toward line M12

Low Tide at 19:10, Dec. 6

1,000



100

10

Dredging 13:01 through 16:19

1

15:10 16:10 17:10

Dredging 17:37 through 18:48

18:10 local 12/6


20:10


21:10

22:10

23:10

1000

H

December 6 Low Tide Mooring 6 Bottom OBS Reflectance

Flow is upriver toward line M12 Low tide at 19:10, Dec. 6


100


10




1


Figure 11G and 11H. Comparison of turbidity in the surface water, and optical backscatter

(in millivolts) in the bottom water at mooring 6, Lower Passaic River, New Jersey, during the low tide at 19:10 on December 6, 2005, and the low tide at 6:50 on December 7, 2005.

108



PCB Homologs Dec 6 PM

40

35

30

25

20

15

10

5

TD Dec 6 PM

TU Dec 6 PM

TU Dec 1 (background)

TD Dec. 1 (background)

TD Dec. 12 (Background)

Core C 0 to 1 ft.

0

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

Figure 11I. Percentage of polychlorinated biphenyl (PCB) homologs by weight for pilot dredge background samples collected December 6, 2005, and bed sediment samples from 2004 core C (0 to 1 ft.) from the Lower

Passaic River, New Jersey.

[C, core transect C in figure 3; TU, upriver sample site; TD, downriver sample site].

109



December 7 - a.m.

Dredging on December 7 was conducted for only one period – from 7:44 until 15:38; a total of 143 unique dredge bites were taken between the NJSPC XY coordinates 594185-

695487 and 594345-695465 (corresponding to dredge cells A1 through B1) (fig. 3). From

8:00 to 11:45, the flow direction was upriver, and from 1245 to the end of dredging; the flow was downriver. Cross-sectional monitoring for SS was conducted along both lines from 8:00 to 12:30 and again from 14:30 to 16:30. Sampling for chemical constituents was conducted from 930 to 12:30 along both lines during the time flow was upriver;

TOPS sampling was not conducted during the afternoon. Samples collected Dec. 7 were evaluated as a morning samples (sampled for chemical and SS analysis); during the afternoon period samples were collected for SS. No substantial problems were associated with the sediment or chemical sampling.

Suspended Sediment

The concentrations of SS at lines M12 and M56 in the surface and bottom water samples followed a similar pattern during the dredging (fig. 12A). For the surface and bottom water samples collected at the downflow line M12, concentrations of SS began increasing at 8:00 in both the surface and bottom water. After initially rising, the concentrations in the surface water remained at about 15 to 25 mg/L until 11:30, after which time they decreased. Because the flow was upriver from line M56 to line M12, the increased SS in successive samples from the upflow line M56 cannot be attributed to dredging. The concentrations of SS for line M56 followed nearly the same pattern as for line M12; first increasing, peaking at 10:30, and then decreasing. The concentrations of SS in surface water from line M56 were very high in the first two samples, but then decreased until

9:00 after which time the concentrations increased steadily throughout the remainder of the morning.

110



Turbidity

The turbidity data from downflow mooring 2 shows that turbidity increased steadily in bottom and surface water beginning at about 10:00 (fig. 12B). Turbidity also increased in the bottom water at mooring M1, where it peaked at 11:00 before declining as the reversal in flow direction approached. During this time, the turbidity in the bottom water at the upflow mooring M6 increased sharply beginning at 9:30, peaking at 1:00, thereafter declining to moderate levels over the remainder of the afternoon (note that after

12:00 the M56 line was downflow) (fig. 12C). Turbidity in the surface water at M5 was also high during the time flow direction was upriver. However, turbidity was not elevated in the surface water at M6. These data confirm the increase in concentrations of SS in the cross-channel samples from lines M12 and M5.


Dredging began on December 7 at the end of low tide, continued through high tide, and ended almost at the time of maximum low tide in the afternoon (fig. 12D). Beginning at about 10:00, the bottom water salinity increased sharply, as the saltwater interface moved upriver through the area, and peaked at about 11:30. In the surface water, the salinity increase was more gradual and ultimately reached a level of about one-fourth the salinity of the bottom water. As dredging concluded and the salinity was declining as the tide lowered (fig. 12D). The dredging was conducted through the entire upriver velocity cycle, through the time of no flow at high tide, then continued until maximum downriver velocity was attained (fig. 12E). Thus, the increase in concentration of SS in the crosschannel monitoring samples and the increase in turbidity correlate almost exactly with the passing of the saltwater interface (first upriver and later downriver) and with the time of maximum flow velocities in both directions.

111




Additional evidence for the movement of the maximum turbidity through line M12 was found by comparing the turbidity measurements made at mooring 2 during the high tide at 12:15 on December 7 with the next high tide that occurred at 1:40 a.m. on Dec. 8 (fig.

12F-I). The turbidity data were aligned at the time of maximum high tide for the two cycles, and the data were plotted from 4 hours before until 4 hours after high tide was reached. Almost identical OBS readings were recorded for the two cycles in the bottom water at mooring M2, showing that the elevated turbidity in the bottom water that occurred during the dredging was not anomalous (fig. 12F). In the surface water at mooring M2 (downflow, fig. 12G), the turbidity was lower during the time dredging than occurred at the 1:40 tide on Dec. 8 cycle. However, after the high tide at 12:15 onDec. 7, the turbidity was substantially higher than during the tide cycle on Dec. 8– but this increased turbidity occurred when the flow direction was downriver and so cannot be attributed to dredging. The surface-water turbidity measured at mooring M1 on Dec. 7 was similar to the turbidity measured for the Dec 8 high tide, although a few short peaks in turbidity occurred during Dec. 7 (fig. 12H). The OBS measurements in the bottom water at mooring M1 were collected on a coarse (30 minute) time scale and so do not contain the detail observed in the OBS readings at the other moorings; however, the turbidity data plot in nearly identical patterns through both tide cycles reaching high levels after high tide was reached and during the last hour of dredging.


The sediment load mass balance were calculated for December 7 for two time periods,

8:00 to 12:30 when flow was upriver and 12:30 to 16:30 when flow was downriver (table

12). For the morning upriver flow period, the imbalance in sediment load was calculated to be +3.2 percent, showing there was no difference between sediment loads at the two mooring lines.

112



Table 12. Summary of sediment mass and loads, Lower Passaic River, New Jersey,

December 7, 2005. [kg, kilograms; totals are rounded]

Time at

M12

Mass of sediment passing


Time at

M56

Mass of sediment passing M56, in

Kg/30 minutes


(M12-M56),

in kg/30 minutes


1

,

in percent

8:00-830 -238

Upriver flow – morning

700 4,330

830-9:00 -2,050 1,370

9:00-930 -2,900 -1,390

930-1000 -3,710 -1,380

1000-1030 -5,460 -5,100

-7,000

1100-1130 -7,040 -7,200

1130-1200 -3,420 -6,960

1200-1230 -1,280 -4,390

1230-1300 492 -1,920

Total -30,600 -29,600

Downriver flow- afternoon

3,580

3,150

4,820

9,020

14,900

9,890

23,500

24,680

Total

Total 1230 to 2030

52,600

130,300

93,500

217,600

-4,570

-3,420

1,920

167

-1,510

52

-2,340

63

-357

6.5

2,000

-40

158

-2.2

3,540

-104

3,110

-242

2,410

971

490

+3.2

-3,080 -627

-589 -23

-2,560 -113

-6,230 -223

-10,700 -253

-5,940 -150

2,650 10

-14,500 -142

-78

-40,900

-87,300 -67

Total 24 hours 191,000 318,000 -12,7000 -66


113



Sediment Chemistry

With the exception the last cross-channel aliquot, all of the samples analyzed were collected during upriver flow. The concentration of total PCBs in the upflow sample collected at line M56 (downriver of the dredge) during Dec. 7 was 1,050

μ g/kg, whereas in the downflow sample (upriver from the dredge at line M12), the concentration of total

PCB was 1,230

μ g/kg, an increase of 182

μ g/kg, or 17 percent (table 4). Concentrations of total dioxin/furans in these samples decreased from 14.6 ng/kg to 12.2 ng/kg, a decrease of 16 percent. The concentrations of 2,3,7,8-TCDD decreased from 1,080 ng/kg at line M56 to 342 ng/kg at M12 (a decrease of 68 percent) and 2,3,7,8-TCDF decreased from 30 ng/kg to 26 ng/kg, a decrease of 13 percent. Likewise, the concentration of total

4,4’-DDTs decreased from 214

μ g/kg at M56 to 169

μ g/kg at M12, a decrease of 22 percent.

A comparison of the concentrations of indicator compounds in the SS with those in the bed sediment showed that the SS samples had concentrations of total PCBs, total

PCDD+PCDF and 2,3,7,8-TCDD that were within the range for the bed sediment. The concentration of 2,3,7,8-TCDD for the upflow sample was elevated to a level similar to those in the deeper river-bed sediment (2 to 3 ft.). The concentrations of 2,3,7,8-TCDF and total 4,4’-DDT in upflow and downflow samples were within the range for the bed sediments. The ratios of concentrations of 2,3,7,8-TCDD to total tetra-TCDD also were within the range of those for the bed sediment; however, the ratio in the downflow sample (0.91) was at the high end of the range for bed sediment, because of the high

2,3,7,8-TCDD concentration in this sample.

Concentrations of total PCBs in the upflow and downflow samples were within the range reported by NJCARP for SS in the PAS-1 and Newark Bay samples. The concentration of total PCDD+PCDF in the upflow sample was greater than the range reported by

NJCARP, but concentrations in the downflow sample was within the range. As noted previously, the concentration of 2,3,7,8-TCDD in the upflow sample was very high and exceeded the range reported by NJCARP. This supports the findings in this study that the natural range of concentrations of 2,3,7,8-TCDD is larger than the range reported by

114



NJCARP. The concentration in the downflow sample was within the NJCARP range, as was the concentration of 2,3,7,8-TCDF in both the upflow and downflow samples. The concentrations of total 4,4’-DDT in both samples was higher than the range reported by

NJCARP.

Concentrations of dissolved compounds were measured only in the upriver (downflow) samples. The concentrations of dissolved PCBs were within the range for the NJCARP samples.

December 7 – p.m.

Samples collected during the afternoon of Dec. 7 were analyzed only for SS concentrations. With the exception of the last sample of bottom water collected from downflow line M56, concentrations of SS in samples collected from 14:30 to 16:30 were less than 15 mg/L and increased only slightly throughout the afternoon. The concentrations of SS in the surface water collected downflow at M56 decreased through the afternoon but, as mentioned, increased in the very last sample collected.

Concentrations of SS in samples from the upflow line M12 were also less than 15 mg/L and relatively steady during the afternoon.

Turbidity

The turbidity at upflow line M12 increased steadily throughout the afternoon, peaking between 13:00 and 14:00 (fig. 12A). Because the flow was downriver after 12:00, the peaks in turbidity at line M12 that occurred in the afternoon cannot be attributed to dredging. Instead, the rise in turbidity likely resulted from the downriver transport of SS that previously had been transported upriver by tidal flow. The turbidity measured in the bottom and surface water downflow at M5 and M6 was generally steady throughout the afternoon, although an increase was detected in the bottom water at M6 at 14:00, after which it decreased sharply. Turbidity in the bottom water at M6 and the surface water at

M5 began to increase at about 16:00 and remained elevated for about four hours through

20:00. A sharp increase occurred in the surface water turbidity of M6 beginning shortly

115


Not USGS Approved (Revised September 2006) before 19:00; however, all of the increases in turbidity occurred after 15:38 when the dredging operations had finished for the day. During this time, the downriver flow velocity was more than 40 cm/s, so only a release at the very end of the dredging could possibly have caused the increase in turbidity that was measured in the downflow samples after 16:00. There was no clear indication that turbidity increased downflow from the ongoing dredging. The turbidity data confirm the increase in SS concentrations measured in the last transect sample collected from the cross-channel monitoring at line

M56 at 16:00, and also show that high levels of SS remained in the water column for about 4 hours throughout the evening low tide cycle (ending at 21:00), well after dredging had ended.

Salinity and Velocity

During the afternoon of December 7, the salinity of the bottom water was elevated until approximately 14:00, when it began to decrease sharply. In the surface water, however, the salinity decrease was gradual and did not reach freshwater values until 17:30. During this period, the velocity of both the bottom water and surface water increased steadily, and there was a marked difference between the velocity at the bottom and surface; the velocity in the surface water was about 40 cm/s greater than in the bottom water. Thus, the afternoon dredging and sampling occurred at the saltwater interface, and likely its associated zone of high turbidity passed through the dredging area.

Sediment Loads and Mass Balance

For the afternoon period when flow was downriver, the sediment loads mass balance was calculated to be -78 percent, which is greater than the assumed level of significance (table

12). If the length of time over which the sediment load was integrated was increased to include the entire period of downriver flow, the imbalance decreased slightly to -67 percent. The mass-balance values support the finding that that more sediment passed the downflow line M56 than passed line M12 during this period.

116



Sediment Chemistry

The chemical sampling was conducted only during the morning period (until 12:30) when the flow was upriver. No sampling or other tests were performed to determine the chemistry of the sediment during the afternoon downriver flow.

117



25

20

15

10

35

30

Flow upriver to

M12





5

Dredging

0

700 730 800 830 900 930 1000 1030 1100 1130 1200 1230 1300 1330 1400 1430 1500 1530 1600 1630 1700

Local Time

Figure 12A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December 7,


118



100

90

60

50

40

30

80

70

20

10

0


Backscatter mooring M2 bottom


Backscatter mooring M1 bottom


M12

1 point

Dredging


M12

60

50

40

30

20

10

0

Local time

Figure 12B. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M12, Lower Passaic River, New Jersey, December 7, 2005.

December 7 Mooring 5-6

100

90


M12

Flow up river toward line

M12

80




70

LT HT

Dredging

LT

Local time

Figure 12C. Surface-water turbidity and bottom-water optical backscatter (in millivolts) at line M56, Lower Passaic River, New Jersey, December 7, 2005.

119



December 7 Mooring 2 Water Elevation and Salinity

4

3

2

1

7

6

5

0

-1

-2

12

11

10

9

8

Water elevation



Dredging

Local Time

Figure 12D. Water elevation and salinity at mooring 2, Lower Passaic River, New Jersey,

December 7, 2005.


100

+ = East flow to Newark Bay Flow upriver to line M12

80

Flow upriver to

line M12

60

12

11

10

9

8

7

6

5

4

3

2

1

0

40

20

0

Bottom ADCP bin

-20

Average ADCP bins < 1m from surface

-40


-60

LT HT

Dredging

LT

-80

Local time

Figure 12E. East-west velocity at mooring 2, Lower Passaic River, New Jersey,

December 7, 2005.

120

40

35

30

25

20

15

10

5



December 7 High Tide Mooring 2 Bottom OBS Reflectance

50

F

45

Flow is upriver

toward line M12

High tide at 12:15, Dec.

7

Hight tide at 1:40, Dec. 8

High tide at 12:15, Dec. 7


Dredging from 7:44 to 15:38

0

Time before or after high tide

December 7 High Tide Mooring 2 Surface Turbidity

30

25

20

15

40

35

50

G

45

Flow is upriver toward line M12




10

5

0

8:15

9:15


10:15

11:15 local 12/7


13:15

14:15 15:15 16:15


Figure 12F and 12G. Comparison of turbidity in the surface water, and OBS backscatter (in millivolts) in bottom water at mooring 2, Lower Passaic River, New Jersey, during the high tide at 12:15 on December 7, 2005, and the high tide at 1:40 on December 8, 2005.

121




14

H

12

High tide at 1:40, Dec. 8 Flow is downriver toward line M56

10

8

6


4


High tide at12:15, Dec. 7


2

Dredging from 7:44 to 15:38 Dec. 7

0



50

45

40

25

20

35

30

I



Hight tide at 1:40, Dec. 8


Flow is downriver toward line M56

15

10


5


0

Time beforeor after high tide

Figure 12H and 12I. Comparison of turbidity in surface water, and optical backscatter (in millivolts * 1000) in bottom water at mooring 1, Lower Passaic River, New Jersey, during the high tide at 12:15 on December 7, 2005 and the high tide at 1:40 on December 8, 2005.

122



December 8

Dredging on December 8 was conducted from 9:20 to 13:27. A total of 85 unique dredge bites were taken between the NJSPC XY coordinates 594318-695472 and 594414-

695476 (corresponding to dredge cell C1) (fig. 3). During all but the last 30 minutes of dredging, flow was upriver from line M56 to line M12. Cross-sectional monitoring for SS was conducted from 8:30 to 16:00 (samples were not collected at 10:00, 14:00, and 14:30 along line M56), and from 7:30 to 15:30 (samples were not collected at 8:30 and 13:00) along line M12 (fig. 13A). Samples for chemical analysis were collected during upflow from 10:30 to 13:30 along both lines. No substantial problems occurred with the sediment or chemical sampling.

Suspended Sediment

The concentrations of SS in samples collected at both lines followed similar trends (fig.

13A). Concentrations were low until 9:30 when they began to increase, and peaked at

11:00, after the concentrations fell steadily until 16:00. This rise and fall in concentrations of SS occurred nearly simultaneously at both monitoring lines. Although the concentrations in the bottom water at both lines followed the same trend, the maximum concentration reached at the downflow (upriver line M12) line was almost 30 mg/L greater than at the upflow line. Because flow was upriver during most of the dredging, the increase in concentrations of SS at line M56 cannot be attributed to dredging.

Turbidity

Turbidity and OBS (fig. 13B and 13C) at downflow line M12 confirm the increase in SS in the cross-channel samples. As was the case for SS, OBS turbidity increased in the bottom water at M1 and M2 beginning about 10:00 and reached maximum values at

11:00 (M2) and 12:00 (M1), after which values decreased at both moorings. The turbidity in the surface water at M2 was low and steady until 11:30 when a very sharp but shortlived spike in turbidity occurred (fig. 13B). The difference between the turbidity

123


Not USGS Approved (Revised September 2006) measured in the surface water at M1 and at M2 is striking – the well defined spike of turbidity that occurred at M2 is suggestive of the passing of a small “slug” of SS, perhaps related to stirring by boat traffic or debris. Similar spikes are evident in the bottom water of M1 at 3:00 and again at 18:00. Whatever the cause, the turbidity in the surface water at

M2 was low and was not greatly affected by the spikes, nor did it change as the dredging progressed. This differs from the turbidity of the surface water measured during dredging at the upflow mooring M5, which gradually increased. Unlike the turbidity spike measured at the surface of M2, the rise and fall in turbidity at M1 in both the surface and bottom water were substantial and well defined. The turbidity in the bottom and surface water at the downflow moorings M5 and M6 (fig. 13C) also increased, peaked, and then decreased concurrently with turbidity at M12. These data confirm the increase in concentrations of SS measured in the cross-sectional monitoring in the bed sediment and show that nearly simultaneous increases in SS occurred at both lines.


The dredging occurred during a sharp increase in salinity in both the bottom and surface water at mooring M2 (fig. 13D). The increase in salinity began shortly after 10:00 while the dredge operations were underway and occurred simultaneously with the increase in turbidity shown in figure 13C. The salinity of the surface-water rose to high levels (8

PSU) on the Dec. 8, close to the value for the bottom water (10.5 PSU). In contrast, on

Dec. 7 (fig. 12D), the salinity of the surface-water reached only 2 PSU. Dredging was conducted throughout the entire upflow velocity cycle (fig. 13E).

124




The turbidity measured on Dec. 8 at the downflow mooring line M12 was compared to the turbidity measured over the next high tide cycle, which was reached at 2:20 on Dec 9.

Aligning the turbidity data on the time of maximum high tide (fig. 13F and 13G), showed that the surface turbidity at mooring M2 on Dec. 8 was low and constant, and was similar to the turbidity during the high tide later that night. Between 2 and 4 hours before each high tide, the turbidity in the surface water was low and steady and nearly identical in the two cycles – low and steady. The turbidity on Dec 9, however, began to rise about 2 hours before maximum high tide was reached. This likely was due to the storm that passed through the area during that time. However, during Dec. 8, the turbidity increased only slightly, beginning at 13:00 as the flow direction reversed. Over the next 6 hours, turbidity remained low and nearly constant and clearly did not increase during the dredging. Therefore, no indication was observed that dredging affected the surface-water turbidity does not exist. A similar conclusion can be made for the turbidity in the bottom water (fig. 13G). Almost identical turbidity was present in the bottom water for the two successive high tides – rising steeply before declining towards the end of the upriver flow.

125




The sediment loads and mass balance calculated for December 8, for the period 9:00 to

13:30 (table 13), had an imbalance of -23 percent. This indicates that sediment was lost between the upflow mooring line M56 and the downflow line M12; however, this difference is within the assumed level of significance, so the loads are essentially equal between the two monitoring lines.

Table 13.

Summary of sediment mass and loads, Lower Passaic River, New


[kg, kilograms; totals are rounded]

Time at

M12

Mass of sediment passing M12, in kg/30 minutes Time at M56





1

in

, percent

-2,810

-386

-3,420

235

1000 -5,520 9:00 532 -6,050

110

-5,640

63

1100 -15,200 1000 -8,640 -6,570

43

Total

Total 24 hours

-67,100

30,400

-82,800

50,500

-9.9

11,500

-94

11,000

-197

11,000

-755

5,250

370

15,700

-20,100

-23

-66


126



Sediment Chemistry

Samples for analysis of organic compounds were collected n Dec. 8 from 10:30 to 13:45, when flow was upriver towards line M12. The concentration of total PCBs in samples collected on Dec. 8 was 1,380

μ g/kg in the upflow (downriver) sample and 791

μ g/kg in the downflow sample, showing that total PCBs decreased by 588

μ g/kg or 43 percent

(table 4). Concentrations of total dioxin+furans also decreased (-26 percent); however, the concentration of 2,3,7,8-TCDD increased from 510 ng/kg to 2,680 ng/kg (+425 percent). A large increase was not observed in the concentration of 2,3,7,8-TCDF, which decreased from 27 ng/kg to 18 ng/kg (-33 percent). The concentration of total 4,4-DDT’s also decreased from 218

μ g/kg to 89

μ g/kg in the downflow sample, a decrease of 59 percent.

The concentrations of total PCB in the upflow sample were within the range of concentrations reported for the bed sediment; however, the concentration of total PCBs in the downflow sample was lower than the range. The concentrations of total

PCDD+PCDF in both samples also were within the range for bed sediment. The 2,3,7,8-

TCDD concentration in the upflow sample was within the range for bed sediments, but the downflow sample had a concentration much greater than was reported for the 2004 cores. The concentrations of 2,3,7,8-TCDF in the upflow and downflow samples were lower than the range reported for bed sediment. The ratios of the concentrations of

2,3,7,8-TCDD to tetra-TCDDs in the upflow and downflow samples were within the range for in the 2004 cores, although the ratio for the downflow sample was quite high

(0.98), the highest of any sample collected in this study. The concentration of total 4,4’-

DDT in the upflow sample also was much greater than the range of concentrations in the bed sediment, whereas the concentration in the downflow sample was within the range.

The concentrations of total PCBs in both samples were within the range reported by

NJCARP for the PAS-1 and Newark Bay samples. The concentration of total

PCDD+PCDF in the upflow sample was higher than the range, but the concentration in the downflow sample was within the range reported by NJCARP for this constituent.

127



Both samples had concentrations of 2,3,7,8-TCDD that were higher than the range reported by NJCARP. The concentrations of 2,3,7,8-TCDF were within the range, but the concentration of 4,4’-DDT in the upflow sample was greather than the range reported by

NJCARP for suspended sediment. Concentrations of dissolved constituents were measured only in the upriver (downflow) samples that were collected on Dec. 8 from line

M12. The concentration of dissolved PCB was within the range of concentrations reported by the NJCARP.

128



100

90

80

70

40

30

20

60

50

Moorings 1-2 Downflow of dredge area





10

Dredging

0

700 730 800 830 900 930 1000 1030 1100 1130 1200 1230 1300 1330 1400 1430 1500 1530 1600 1630 1700

Local Time

Figure 13A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December 8,


129



150

140

130

120

110

100

90

80

70

30

20

10

0

60

50

40




Backscatter, mooring M, bottom


M12

Dredging

1 point


M12

Local time

Figure 13B. Surface-water turbidity and bottom-water optical backscatter

(in millivolts) at line M1, Lower Passaic River, New Jersey, December 8, 2005.

130



December 8 Mooring 5-6 Surface and Bottom Turbidity

150

140

130

120

110

100

90

80

70

60

50

40

30

20

10

0




LT


M12

Dredging

HT

LT


M12

Local time

Figure 13C. Surface-water turbidity and bottom-water optical backscatter

(in millivolts) at line M56, Lower Passaic River, New Jersey, December 8, 2005.

131



December 8 Water Elevation and Salinity

12

11

10

9

8

7

6

5

4

3

2

1

0

-1

-2

Water elevation



Dredging

Local time

Figure 13D. Water elevation and salinity at mooring 2, Lower Passaic River,

New Jersey, December 8, 2005.

8

7

6

5

4

1

0

3

2

12

11

10

9

132



December 8 Mooring 2 AM

100

80

60


Flow upriver

to line M12

40

20

0

-20

Bottom ADCP bin

-40


-60

LT

-80

Dredging

HT

Average ADCP bins

<1meter from surface

Local time

Figure 13E. East–west velocity measured at mooring 2, Lower Passaic River,

New Jersey, December 8, 2005.

133




50

45

F

25

20

15

40

35 Flow is upstream toward line M12

30

Maximum 82.5 NTU at

2:20 (11:25 local time)

High tide at 13:26, Dec 8


Flow is downstream towards line M56


10

5

0

9:45

10:45


11:45

12:45 local 12/8


14:45 15:45 16:45 17:45



40

35

30

25

20

50

G

45


Flow is downriver toward line M56



High Tide @ 2:20 12/9

15

10

Dredging from 9:20 to 13:27 High Tide @ 13:45 12/8

5

0

9:45

10:45

11:45

12:45

14:45

15:45

16:45


Figure 13F and 13G. Comparison of turbidity in the surface water, and OBS backscatter (in millivolts) in bottom water at mooring 2, Lower Passaic River, New Jersey, during the high tide at 12:15 on December 7, 2005, and the high tide at 1:40 on December 8, 2005.

134



December 10

Dredging was conducted twice on December 10, from 7:45 to 10:38 (am sampling) and from 12:39 to 15:18 (pm sampling). During the morning dredging (7:45 to 10:38) 88 unique dredge bites were taken between the NJSPC XY coordinates 594402-695515 and

594383-695543 (corresponding to dredge cell D1) (fig. 3). The flow was downriver

(toward line M56) during the entire morning of dredging.

During the afternoon, 58 unique dredge bites were taken between the XY coordinates

594459-695483 and 594485-695457 (corresponding to dredge cell E1). Flow during the afternoon dredging was upriver toward line M12. Cross-sectional sampling for SS was conducted from 7:30 to 16:00 (samples were not collected at 11:00 and at 11:30 from line M56) and 7:00 to 16:00 along line M12 (samples were not collected at 11:00 and

11:30). Sampling for chemical analysis was conducted from 7:30 to 10:30 (am sampling) on both lines, from 12:30 to 15:00 (p.m. sampling) along line M56, and from 12:30 to

14:00 along line M12. Sampling along line M12 was stopped early, after the 14:00 sample, because of equipment malfunction.

December 10 - a.m.

Suspended Sediment

Concentrations of SS in the morning samples from lines M12 and M56 were nearly identical (fig. 14A). Concentrations increased slowly from about 25 mg/L to slightly more than 50 mg/L in final samples collected at 10:30. Close inspection of the values shows that SS in samples from the upflow line M12, in the bottom and surface water, were slightly greater than in corresponding samples from the downflow line M56.

Because flow at this time was downriver, the increase in SS content in the line M12 samples cannot be the result of dredging.

135



Turbidity

The turbidity in the bottom water at the downflow mooring M6 and in the bottom and surface water at M5 increased greatly during the morning as dredging began, and peaked at about 10:15, after which it decreased at all locations (fig. 14B). However, turbidity in the surface water at M6 did not change during this time. Only in the bottom water at mooring M2 (up-flow, fig. 14C) was a marked increase in turbidity detected. Turbidity in the surface and bottom water at M1 increased slowly but steadily through the latter half of the morning. Turbidity in the surface water at M2 was steady until just after 10:00 when the flow direction reversed. These data confirm the gradual increase in SS concentrations measured in samples from the downflow and upflow cross-channel monitoring lines.


The morning dredging was conducted during the ebbing tide as the water level decreased and the water freshened (fig. 14D). The salinity decreased only slightly throughout the morning. During this time, the east-west water velocity was constant throughout the water column at about 30 cm/s, until about 10:00 when the velocity decreased rapidly as the flow direction reversed (fig. 14E). Thus, the increased turbidity observed at the downflow line M56 occurred after the saltwater interface had passed and during a period of high and constant downriver velocity. Shortly after the dredging and sampling ended, the water flow rapidly changed direction and the upfloow velocity increased, during a short high tide. Compared with the velocities on other monitored days, the “stepped” velocity profile during the morning of December 10 is unique and may have affected the pattern of turbidity.

136




The surface water turbidity and bottom water OBS measurements made at the downflow mooring line M56 during the morning low tide cycle of December 10 were compared with the turbidity and OBS measured during the next lowtide cycle, which occurred at

22:40 on December 10 (figs. 14 F-H). In the surface water at mooring M6 (fig. 14F), the turbidity measured during the lead up to low tide was almost identical in both cycles; the turbidity was low and showed little fluctuation throughout the tide cycles. For the most part, this was also observed in the bottom water at mooring M6 (fig. 14G); however, close inspection showed that turbidity (OBS) in the bottom water began to increase at about 8:45 in the morning of Dec. 10 (note the log scale used in this plot, which reduces the apparent difference in values). The turbidity measured in the shallow portion of the river channel at the downflow mooring M5 (fig. 14H) during the morning of Dec. 10 was much greater than the turbidity recorded during the evening tide cycle.


The sediment loads and mass balances for December 10 were calculated and are presented in table 14. The loads were offset by 30 minutes to account for the downriver travel time between mooring lines. The sediment loads for the period 7:30 to 11:30 had an imbalance of -33 percent, which is outside the 25 percent uncertainty; therefore, no significant difference was apparent in the loads crossing the two mooring lines.

137



Table 14. Summary of sediment mass and loads, Lower Passaic River, New


[kg, kilograms; totals are rounded]

Time at

M12


Time at

M56





1

,

in percent

Downriver flow – morning

730-800 6,470 -5,730 -89

-699 -7.3

830-900 7,600 -3,390 -45

900-930 7,760 -4,890 -63

930-1000 8,640 -8,930 -103

-463 -5.2

4,690 49

Total 58,500 77,900

Upriver flow – afternoon

-19,400 -33

-9,600 200

-6,790 76

-9,010 54

-3,950 16

3,610 -16

9,010 -73

8,690 -125

5,070 -170

4,760 340

Total

-99,300

-101,000

1,782 -1.8

Total 24 hours

-109,000 -58,300 -50,950 47


Sediment Chemistry

The concentrations of total PCBs in the samples collected during the morning of

December 10 were almost identical at the two monitoring lines, 1,220

μ g/kg in the upriver (and upflow) sample at line M12 and 1,190

μ g/kg in the downriver (downflow) sample from line M56, representing a difference of -2.7 percent (table 4). Concentrations

138


Not USGS Approved (Revised September 2006) of total dioxins/furans in the samples decreased slightly from 13.8

μ g/kg in the upflow sample to 12.5

μ g/kg in the downflow sample, representing a decrease of 9 percent. The concentration of 2,3,7,8-TCDD decreased substantially from 1,590 to 428 ng/kg for the downriver sample (a decrease of 1,160 ng/kg, or -73 percent), whereas the concentration of 2,3,7,8-TCDF increased slightly (9 percent). The concentration of total 4,4’-DDT increased slightly from 158 to 167 ug/kg from the upriver sample, an increase of +5.7 percent.

Concentrations of total PCBs in both samples of SS were lower than the range for the bed sediment, whereas the concentrations of total PCDD+PCDF were within the range of bed sediment values. The concentration of 2,3,7,8-TCDD was within the range for bed sediment, being most similar to the concentrations in the 2-3 ft. depth of the cores collected during 2004. The ratios of the concentration of 2,3,7,8-TCDD to total TCDD in the two samples were 0.89 and 0.67, which are within the range for the bed sediments.

The concentrations of 2,3,7,8-TCDF and total 4,4’-DDT in both samples were within the ranges measured in the 2004 bottom cores.

The concentrations of total PCBs in both of the samples collected on December 10 (a.m.) were within the range of the NJCARP samples. The concentration of total PCDD+PCDF in the upflow sample was higher than the range, but the concentration in the downflow sample was within the range of concentrations reported by the NJCARP work. The concentration of 2,3,7,8-TCDD in the upflow sample was high and exceeded the range of concentrations reported by NJCARP, indicating that the range of concentrations in the river exceeded that reported by NJCARP. The sample collected downflow from the dredging had a concentration of 2,3,7,8-TCDD that was within the NJCARP range, as were the two 2,3,7,8-TCDF concentrations. The concentrations of total 4,4’-DDTs in both of the SS samples were greater than the range reported by NJCARP for PAS-1 and

Newark Bay samples.

139



During the morning of Dec. 10, only the sample from the downflow (down-river) line

M56 was analyzed for dissolved constituents (table 6). The concentrations of dissolved

PCBs in these samples were within the range of the NJ-CARP samples (table 5).

December 10 – p.m.

Suspended Sediment

During the afternoon of December 10, flow was upriver from line M56 to line M12. The concentration of SS in samples from the two lines followed similar trends -- first increasing with the onset of dredging, then decreasing throughout the afternoon.

Initial concentrations of SS were low, and with the exception of the upriver bottom water sample from line M12, were similar to those in samples collected during the morning

(fig. 14A). However, concentrations increased after 12:30 and reached a maximum in the

13:00 and 13:30 samples, after which time the SS concentrations decreased to values similar to those at the onset of dredging. The pattern exhibited by the SS in the bottom water of the downflow line M12 is similar to that at upflow line M56 except that (1) the initial sample at M12 contained a very high SS content, more than 150 mg/L, whereas at

M56 the initial SS concentration was less than 50 mg/L, and (2) the general pattern of the concentrations (first increasing then decreasing) measured at line M12 (down-flow) is offset in time compared to M56; the maximum concentration at line M56 (about 80 mg/L) was reached at 13:00 while at line M12 (20 mg/L) is was reached at 12:30. The concentrations of SS in the bottom water at the downflow line M12 exceeded those measured at the upflow line M56, which was nearly 200 mg/L.

The high concentration of SS at line M12 at 13:30 were, at first, suspicious, perhaps having been generated by the sampling line hitting the bottom. However, this value is now considered real because concentrations remained elevated over the next 1.5 hour period, and the same general concentration pattern (first increasing, peaking, and then decreasing) was observed for both sampling lines.

140



Turbidity

Turbidity in the bottom water at the downflow mooring M1 and M2 (fig. 14C), and the surface water at mooring M2, increased during the afternoon. The turbidity in the bottom water at moorings M1 and M2 and at the surface water at M2 increased to high values

(>150 NTU) before returning to near their initial low levels, following the same pattern as observed in the cross-sectional SS samples (fig. 14A). Turbidity at the surface of mooring M2 remained elevated until much later in the day, when at about 17:00, a very sharp decline occurred as values returned to pre-dredging levels. This pattern of a sharp increase followed by a sharp decrease (at M2) may be real; however, the jump in turbidity may also indicate instrument related problems such as the clogging of the sensor. Also, turbidity in the surface water at M1 remained low and steady during this period even though turbidity was high in the bottom water at this mooring. Over the same time period the turbidity in the bottom water at the upflow mooring M6 and in the surface water at M5 rose to high levels before declining as the end of the upriver flow was approached. The turbidity in the surface water at M5 remained low and steady, similar to that measured at M1. The turbidity measured at the two sampling lines confirmed the pattern shown in the concentrations of SS that were measured in the bottom water, and showed that the SS increased, peaked, then decreased during the dredging.

Water Salinity

The dredging during the afternoon of the Dec. 10, occurred as the salinity of the bottom and surface water increased with the rising tide (fig. 14D). The salinity in the bottom and the surface water rose to high levels, about 12 PSU in the bottom water and 9 PSU in the surface water. Thus, the increase in turbidity and SS concentrations during the afternoon coincided with the upriver movement of the saltwater interface and, likely, the associated zone of high turbidity. The high turbidity that was measured in the surface water at mooring 2 (fig. 14B) could be related to the high salinity that was measured on this day.

141




The turbidity and optical backscatter data for the afternoon tidal cycle on December 10

(high tide at 15:45 on Dec. 10; fig. 14I) at the downflow line M12 were compared with the values measured during the next high tide cycle which occurred at 4:45 on Dec. 11

(fig. 14K). The turbidity in the surface water at mooring M2 (fig. 14I) was similar during the two tide cycles until approximately 2 hours before the afternoon high tide was reached on Dec. 10, when the turbidity doubled from about 50 NTU up to 100 NTU. The turbidity remained at near this value until about 1 hour after high tide was reached. This

“step” in turbidity is odd, and may indicate an instrument problem such as the clogging of the sensor or other malfunction; however, if it is real, then a significant increase in turbidity occurred at mooring M2 during afternoon of Dec. 10. There was no indication of a similar jump during the tidal cycle on December 11. The OBS backscatter in the bottom water followed the same pattern during the two cycles, but reached higher levels during the high tide cycle on Dec. 10 (fig. 14I, note log scale). The backscatter in the surface water at M1 was similar during the two cycles but was elevated from the turbidity measured during Dec 11.


To calculate the afternoon sediment load and mass balance, the loads were offset by 60 minutes to account for the travel time between moorings at an average upriver flow velocity of -20 cm/s. The calculated sediment load for the afternoon (table 14) crossing the upflow line M56 almost exactly equals the load across the downflow line M12; the difference is -1.8 percent. Thus, no difference was observed between the sediment loads at the two monitoring lines.

142



Sediment Chemistry

Nearly identical concentrations of total PCBs were measured in the SS samples collected during the afternoon of December 10, only a small difference (6.4 percent) was measured between the upflow (1,210

μ g/kg at line M56) and the downflow (1,290

μ g/kg in the upriver sample at line M12) samples (table 4). The concentration of total dioxin/furans increased by 16 percent, from 11.9

μ g/kg in the downriver sample to 13.8

μ g/kg in the upriver sample. The concentration of 2,3,7,8-TCDD was nearly identical in the two samples, differing by only +2.2 percent. The concentration of 2,3,7,8-TCDF increased by

23 percent, whereas the concentration of total 4,4’-DDT increased substantially (295 percent), nearly tripling from 76

μ g/kg to 224

μ g/kg.

The concentrations of total PCBs in the two SS samples were lower than the range reported for bed sediment, while total PCDD+PCDF, 2,3,7,8-TCDD, 2,3,7,8-TCDF, and total 4,4’-DDTs were all within the range of concentrations for bed sediment. The ratios of the concentration of 2,3,7,8-TCDD to total-TCDDS (0.65 in both samples) were low but within the range for bed sediment.

Concentrations of total PCBs, 2,3,7,8-TCDD, 2,3,7,8-TCDF, and total 4,4’-DDTs were all within the range of values reported by NJCARP for SS. Concentrations of total

PCDD+PCDF in the downflow sample exceeded the range of concentrations reported by

NJCARP. Dissolved components were not measured in afternoon samples collected on

Dec. 10.

143



250

200

150

100






50

Dredging

0

700 730 800 830 900 930 1000 1030 1100 1130 1200 1230 1300 1330 1400 1430 1500 1530 1600 1630 1700

Local Time

Dredging

Figure 14A. Concentrations of suspended sediment in cross-sectional samples collected from the Lower Passaic River, New Jersey, December

10, 2005. Vertical lines delineate intervals when chemical samples were collected.

144



300

250

200

150





Flow upriver to line M12


100

Dredging

50

Dredging

0

Local time

Figure 14B. Surface-water turbidity and bottom-water optical backscatter

(in millivolts) at line M12, Lower Passaic River, New Jersey, December 10,

2005.

145



300

250

December 10 Mooring 5-6 Turbidity and OBS Reflectance





200

150

100


50

Dredging

LT

HT LT

0

Local time

Figure 14C. Surface-water turbidity and bottom-water optical backscatter

(in millivolts) at line M56, Lower Passaic River, New Jersey, December 10,

2005.

146



December 10 Mooring 2 Water Elevation and Salinity

12

11

10

9

8

7

6

5

4

3

2

1

0

-1

-2

Water elevation



Dredging

Local time

Figure 14D. Water elevation and salinity at mooring 2, Lower Passaic River, New Jersey,

December 10, 2005.

December 10 EW Velocity at Mooring 2

100


80


8

7

6

5

4

1

0

3

2

10

9

12

11

60

40

20

0

-20

Bottom ADCP bin

-40

Average of ADCP bins

<1 meter from surface

-60



LT

HT

-80

Local time

Figure 14E. East –west velocity measured at mooring 2, Lower Passaic River, New Jersey,

December 10, 2005.

147




50

45

40

35

30

25

20

15

10

5

0

6:30

F






Morning dredging 7:45 through 10:38

7:30 8:30

9:30 local


Afternoon dredging 12:39 through 15:18

11:30 12:30

13:30

14:30

December 10 Low Tide Mooring 6 Bottom OBS Reflectance

1,000

G





100

10


830

Morning dredging

7:45 through 10:38

930

Afternoon dredging

12:39 through 15:18

1

630

730

1130 1230 1330 1430


Figure 14F and 14G. Comparison of turbidity in the surface water, and OBS backscatter (in millivolts) in bottom water at mooring 6, Lower Passaic River, New Jersey, during the low tide at 10:30 on December 10, 2005 and the high tide at 22:40 on December 10, 2005.

148



December 10 Mooring 5 Low Tide Surface Turbidity

100

90

80

70

60




Low tide at 10:30,

Dec. 10

50

40

30

20


Morning dredging 7:45 through 10:38

830 930

Afternoon dredging 12:39 through 15:18

10

0

630

730

1130

1230 1330


Figure 14H. Comparison of turbidity in the surface water at mooring 5, Lower Passaic

River, New Jersey, during the low tide at 10:30 on December 10, 2005, and 22:40 on

December 10, 2005.

149



1000


Flow is up river towards moorings 1-2

SURFACE NTU AM

SURFACE NTU PM

High Tide @ 15:45 12/10

100

10

High Tide @ 4:45 12/11

Afternoon dredging from 12:39 to 15:18

1

11:45

1000

12:45 13:45 14:45 local 12/10

Time before/after High Tide

16:45 17:45



18:45 19:45

BOTTOM OBS AM

BOTTOM OBS PM

High Tide @ 15:45 12/10

100

10

High Tide @ 4:45 12/11

Afternoon dredging from 12:39 to 15:18

1


Figure 14I and 14J. Comparison of turbidity in the surface water, and bottom water OBS backscatter (in millivolts) at mooring 2, Lower Passaic River, New Jersey, during the high tide at 15:45 on December 10, 2005, and the high tide at 4:45 on December 11, 2005.

150




50

45

40

35

30

25

20


High Tide @ 15:45 12/10

SURFACE NTU AM

SURFACE NTU PM

Instrument stopped working after this time

15

10

High Tide @ 4:45 12/11

5

Afternoon dredging from 12:39 to 15:18 12/10

0


Figure 14K. Comparison of turbidity in the surface water at mooring 1, Lower Passaic

River, New Jersey, during the high tide at 15:45 on December 10, 2005, and the high tide at

4:45 on December 11, 2005.

151



Discussion and Summary

Three general observations can be made from the “far-field” monitoring of the Pilot

Dredge program presented in this report. First, the cross-channel sampling that was designed and conducted for this program was apparently able to produce a representative cross-sectional picture of SS in the river during dredging – at least consistent with the turbidity and SS estimated using the reflectance data acquired using the moored instruments. Data from the cross-channel sampling correlated with data fromthe moored instruments regarding the suspended sediment content in the river. Only occasionally did the moored instruments record an increase in turbidity that was not reflected in the composite cross-channel SS samples. These periods of higher turbidity generally were short lived pulses that likely were not captured in the composite samples. The good agreement between the data from the moored instruments and from the composite samples indicates that these sampling routines can be used to accurately monitor dredging activities .

Second, using the concentrations of SS collected during the (cross-channel) monitoring to demonstrate unequivocally that sediment was released from the dredging operation is a difficult task because of the wide variation in natural SS content that can occur during each tide cycle. This natural variability is associated with the presence and movement of the saltwater/freshwater interface in the estuary. Data recorded at by the moored instruments indicate that the saltwater interface and its associated zone of high turbidity migrated through the dredge area with each daily tide. The SS estimated from the reflectance data show that the SS in the river can rapidly change from near 0 mg/L to over 400 mg/L (estimated). This change is the result of the migration of the natural turbidity in the river. The velocity and conductivity data from the moored instruments show that the saltwater interface migrated at various velocities, often migrating through the Harrison Reach of the Lower Passaic River at a very slow rate. As a result, sediment released during dredging would quickly became assimilated and “lost” in the natural zone of high turbidity.

152



Finally, the use of concentrations of indicator species of organic and inorganic compounds to discern dredging releases is difficult because of the wide range of concentrations that were present in the suspended sediment, and the similarity in chemical concentrations of the suspended and the bed sediment. All of the “background” samples collected during this study fall within, or near, the range of concentrations measured in samples previously collected from the river (the NJCARP samples). The few concentrations that were found to exceed the range of “background” concentrations most likely indicate that a larger range of concentrations naturally exists in the river than was previously known. All of the background concentrations obtained from the Pilot Dredge study are within the range of concentrations in the bed sediments (0 to 1 ft. depth) of the dredging area. The concentrations of selected indicator species in the suspended sediment are exceeded only by the concentrations in samples of bed sediment buried deeper than 2 feet. The background samples collected in this study have concentrations of indicator species that are within the range of concentrations found in the surficial (0 to 1 or 2 ft depth) river bed samples. The bed sediment from 0 to 2 ft below the river bed could have been disturbed and released by dredging or by natural erosion/resuspension that occurs in the river.

Although it is difficult to identify the presence of sediment released by dredging, the SS and chemical data obtained during this program still may support (or repudiate) the contention that suspended sediment was released during dredging. To summarize the detailed evaluation that was made of the daily monitoring data, the results of the examination of the SS and chemical concentrations, and data from the moored instruments are framed as questions which are presented in table 15. Ultimately, two questions can be addressed for each day of dredging operations: (1) Did SS concentrations increase from upflow to downflow of the dredging operations? and (2)

Did concentrations of indicator species increase downflow of the dredging activity?

December 5, morning.

The information from the morning dredging period is difficult to interpret because the monitoring was conducted during a flow reversal. Dredging began

153


Not USGS Approved (Revised September 2006) late during the morning after the flow had reversed direction in the river; however the majority of the composite sample was collected when flow was upriver and dredging was not underway. During the period when flow was downriver and dredging was underway, the concentrations of SS downflow from the dredge did not increase. Therefore, there is no evidence that dredging released sediment. Because the chemical samples were collected mainly during upriver flow when dredging was not underway, the chemical data are not easily interpreted; thus, a change in concentrations occurred during dredging could not be confirmed.

December 5, afternoon. Dredging was conducted during the afternoon when flow in the river was in one direction, making the interpretation of the monitoring data more straightforward. The concentrations of SS in the samples collected downflow from the dredging increased substantially from the concentrations measured in upflow samples.

During the afternoon, the SS measured upflow decreased from the values that occurred in the morning. Therefore, the increase in SS downflow from the dredging is most easily explained as the passing of water and sediment that had migrated upriver with the tide earlier in the day. Data from the moored instruments indicate this sediment was likely associated with the saltwater interface and the zone of natural turbidity. The concentrations of indicator chemicals did not change between upflow and downflow samples; therefore, these data do not support the concentrations that contaminated bed sediment was released by dredging.


The dredging was conducted when a reversal in flow occurred in the river, making to interpretation of changes in SS and chemical concentrations difficult.

The concentration of SS increased downflow from the dredge, but this increase began well before the initiation of dredging and cannot be associated with the dredging activity.

The SS concentrations at both monitoring lines decreased as the morning dredging proceeded, which is not consistent with an ongoing release of sediment during dredging.

Although the concentrations of indicator chemicals decreased from upflow to downflow of the dredging, the reversal in flow makes the interpretation of these data equivocal.

154



December 6, afternoon.

The dredging took place during a period of unidirectional downriver flow, making interpretations for this period more straightforward than for the morning. The SS concentrations increased in the samples collected downflow and upflow from the dredging. However, the maximum concentration of SS measured downflow were much greater than the peak concentration measured in the upflow samples, indicating that SS was added to the river. The increase in SS occurred during the time the saltwater interface was migrating downriver through the sampling area, and thus, any sediment added by the dredging was obscured by the natural zone of turbidity. All of the concentrations of indicator chemicals in the downflow samples were greater than those in the morning samples, except the 4,4’-DDTs. Although obscured by the natural variability in the turbidity of the river, the sediment and chemical data support the contention that sediment may have been added to the river during the dredging. Further evidence might be found in the “near-field” data collected from the L and M boat.


Although the morning dredging was undertaken during a flow reversed, flow was unidirectional (upriver) during the time when the sampling was conducted. The SS concentrations in the samples collected from both downflow and upflow from the dredging increased through the early morning, then decreased at both locations as high tide approached and the upriver flow velocity diminished. The saltwater interface moved through the dredge area twice during the morning, so it is likely that variations in SS concentrations reflect the passing of the natural zone of turbidity through the monitored area. The concentrations of all indicator species decreased between the upflow and downflow samples collected during the dredging and were within the range of concentrations considered background. Thus, there is no indication in these data that sediment was released by the dredging.

December 7, afternoon.

Monitoring was conducted only for SS during the afternoon.

The concentrations of SS in both the downflow and upflow samples increased slightly throughout the afternoon. The last down-flow sample collected had a high concentration of SS that might be related to the ending of the dredging operations. Further evidence for

155


Not USGS Approved (Revised September 2006) the presence of a “near-field” sediment release may be evident in data collected by the L and M boat monitoring.

December 8.

Dredging on this day occurred during unidirectional flow (upriver). The concentration of SS in samples collected downflow and upflow from the dredging increased as dredging began, then peaked, and decreased at both sites as dredging proceeded. This pattern is not consistent with an ongoing release of SS by dredging. The saltwater interface passed through the dredging area during this time, so the pattern of SS concentrations is consistent with the passing of the natural zone of high turbidity. The chemical concentrations of most of the indicator species decreased from upflow to downflow monitoring locations. The concentration of 2,3,7,8-TCDD in the downflow sample (up-river) collected on this day was substantially greater than that measured in the upflow sample. The 2,3,7,8-TCDD concentration reported for this sample exceeded the concentrations reported for the 2004 bed-sediment cores, and those in any other samples collected in this study. Only the 2,3,7,8-TCDD congener increased in the downflow sample compared with the upflow sample; all of the other indicators decreased. The high concentration of 2,3,7,8-TCDD is odd, and although analytic problems cannot be ruled out, the high concentration may be indicative of the release of deep bed sediment.

December 10, morning . During the morning dredging, flow was downriver and did not reverse. The SS concentrations measured in samples upflow and downflow of the dredging increased steadily through the morning, showing the same pattern in both locations. The saltwater interface passed through the area early in the morning, so the increase in SS was likely related to the passing of the natural turbidity zone. The concentrations of all indicator species decreased between the two monitoring locations, so there was no indication that sediment was released by the dredging operations during this period.

December 10 afernoon . Flow during the afternoon was upriver and did not reverse during the monitoring period. The concentrations of SS measured in the upflow and downflow samples were greater in subsequent samples collected during the onset of

156


Not USGS Approved (Revised September 2006) dredging, then peaked and decreased in samples collected throughout the afternoon. This pattern is not consistent with a release by dredging; however, the concentrations of SS in samples collected downflow from the dredging were higher than those measured in the upflow samples. The saltwater interface passed through the area during the afternoon dredging, so the increase in SS could be related to the passing of the natural zone of high turbidity. The chemical data are equivocal; although the concentrations of the indicator species were higher in samples collected downflow from the dredging, the difference is within the assumed uncertainty of the analyses. The concentrations in the SS samples were within the range measured in the bed sediments, and within the range of the background samples. Therefore, there is no clear evidence that sediment was released by the dredging.

157



Table 15. Summary of sediment, river conditions, and chemistry measured on the Lower Passaic River, New

Jersey, during the Environmental Dredging Pilot Program, December 5-10, 2005.

[ SS, suspended sediement; PCB, polychlorinated biphenyls; PCDD+PCDF, polychlorinated dioxins and difurans; --, not sampled or analyzed; NJCARP, New Jersey Contaminant Reduction Program]

Date and time of sampling

Dec. 5 a.m.

Dec. 5 p.m.

Location of downflow sample line

M56

M56

Did SS increase in downflow samples during dredging?

No

Yes

Did turbidity increase downflow during dredging?

No

Yes, at both lines, increased then decreased

Yes, at both lines

Was turbidity greater than levels in next tide cycle?

Not evaluated

Did sediment load increase downflow?

Not evaluated

Yes No

1

Dec. 6 a.m.

Dec 6 p.m.

M56

M56

Yes, but then decreased

Yes, at both lines Yes, at both lines, increased then decreased

Yes, at both lines

Not evaluated

Yes, at very end of dredging

No

Not evaluated

Not clear

Dec. 7 a.m. M12 Yes, at both lines

Dec. 7 p.m.

Dec 8.

Dec. 10 a.m.

Dec. 10 p.m.

M56

M12

M56

M12

Yes, at both lines

Yes, increased then decreased

Yes


No




Not evaluated

No

Yes

Yes sediment sampling

Yes

No

Yes

No

1. During the morning dredging on December 6, the flow direction in the river reversed, and both M12 and M56 sampling lines were upflow and downflow from the dredging activity. Line M56 was chosen to represent the downflow sampling site because it was downflow for the longer period of time.

No for morning chemical sampling; yes for afternoon

158




Jersey, during the Environmental Dredging Pilot Program, December 5-10, 2005. -- Continued

[ SS, suspended sediement; PCB, polychlorinated biphenyls; PCDD+PCDF, polychlorinated dioxins and difurans; --, not sampled or analyzed; NJCARP, New Jersey Contaminant Reduction Program]


Location of downflow sample line

Did salinity change during dredging?

Did saltwater interface pass through area during dredging?

Did bottom-water velocity increase during dredging?

Was dredging conducted during period of maximum flow velocity?

Was it likely that zone of maximum turbidity passed through area during dredging?

Dec. 5 a.m.

Dec. 5 p.m.

1

Dec. 6 a.m.

Dec. 6 p.m.

Dec. 7 a.m.

Dec. 7 p.m.

Dec 8.

M56

M56

M56

M56

M12

M56

M12

Yes, surface only

Yes- deep only

Yes, surface only

Yes, decreased


Yes, decreased

Yes, increased

No

Yes

No

Yes

Yes-twice

Yes

Yes

Yes, flow reversal

Yes

Yes, flow reversal

Yes

Yes

Yes


No No

No

Yes

No

Yes

Yes, upriver

No

Unclear

Yes

Yes

Yes

Yes, twice

Yes

Yes Yes

Dec. 10 a.m. M56 Yes, decreased slightly

Yes, increased

Yes Unclear

Dec. 10 p.m. M12 Yes No, decreased Yes Yes

1. During the morning dredging on December 6 the flow direction in the river reversed, and both M12 and M56 sampling lines were upflow and downflow from the dredging activity. Line M56 was chosen to represent the downflow sampling site because it was downflow for the longer period of time

159





[ SS, suspended sediement; PCB, polychlorinated biphenyls; PCDD+PCDF, polychlorinated dioxins and difurans; --, not sampled or analyzed; NJCARP, New Jersey Contaminant Reduction Progam]

How did concentration change between upflow and downflow sample?

Date and time of

1 sampling

Dec. 5 a.m.

Dec. 5 p.m.

Dec. 6 a.m.

Dec. 6 p.m.

Dec. 7 a.m.

Dec. 7 p.m.

Dec 8.

Dec. 10 a.m.

Location of upflow/downflow

Change in total PCB concentration

Change in total

PCDD+PCDF

Change in 2,3,7,8-

TCDD

Change in

2,3,7,8-TCDF

Change in total

4,4’-DDT sample line

M12/M56 Decreased Decreased Decreased Decreased Decreased

Decreased M12/M56 Decreased, but within uncertainty uncertainty

M12/M56 Decreased Decreased Decreased Decreased

M12/M56 Increased

M56/M12 Decreased, but within

No

Decreased, but within

Increased Increased

Decreased Decreased, but within

Increased

Decreased

Decreased

M12/M56

M12/M56 uncertainty

Not evaluated

M56/M12 Decreased Increased Increased Decreased

Decreased, but within uncertainty uncertainty

Not evaluated

Decreased, but within uncertainty

Not evaluated

Decreased uncertainty

Not evaluated

Increased, but within uncertainty

Not evaluated

Decreased

Decreased

Dec. 10 p.m. M56/M12 Increased, but within uncertainty

Increased Increased, but within uncertainty

Increased, but within uncertainty

Increased

1. During the morning dredging on December 6 the flow direction in the river reversed, and both M12 and M56 sampling lines were upflow and downflow from the dredging activity. Line M56 was chosen to represent the downflow sampling site because it was downflow for the longer period of time.

160







Dec. 5 a.m.

Dec. 5 p.m.

1

Dec. 6 a.m.

Dec. 6 p.m.

Dec. 7 a.m.

Dec. 7 p.m.

Dec 8.

Dec. 10 a.m.

Dec. 10 p.m.

Location of upflow

/downflow sample line

M12/M56

M12/M56

M12/M56

M12/M56

M56/M12

--

M56/M12

M12/M56

M56/M12

Total PCB

--

No, lower

No, lower

Yes

No, lower

Not evaluated

No, lower

No, lower

Yes

Was concentration of downflow sample within range of surficial bed sediment ?

Total PCDD+PCDF 2,3,7,8-TCDD 2,3,7,8-TCDF Total 4,4’-DDT

--

Yes

Yes

Yes

Yes

Not evaluated

Yes

No, lower

Yes

--

Yes, 1-2ft layer

Yes

Yes

Yes

Not evaluated

Above

Yes

No, lower

--

Yes, 1-2ft layer

Yes

Yes

Yes

Not evaluated

Yes

Yes

Yes

--

Yes

Yes

No, greater

Yes

Not evaluated

Yes

Yes

Yes


161







Dec. 5 a.m.

Dec. 5 p.m.

1

Dec. 6 a.m.

Dec 6. p.m.

Dec. 7 a.m.

Dec. 7 p.m.

Dec 8.

Dec. 10 a.m.

Dec. 10 p.m.

Location of upflow

/downflow sample line

M12/M56

M12/M56

M12/M56

M12/M56

M56/M12

M12/M56

M56/M12

M12/M56

M56/M12

Was the constituent concentration in the downflow sample within the range for NJCARP samples?

Total PCB

Not evaluated

Yes

Yes

Yes

Yes

Not evaluated

Yes

Yes

Yes

Total PCDD+PCDF

Not evaluated

No

Yes

Yes

Yes

Not evaluated

Yes

Yes

Yes

2,3,7,8-TCDD

Not evaluated

Yes

Yes

Yes

Yes

Not evaluated

No, lower

Yes

Yes

2,3,7,8-TCDF

Not evaluated

Yes

Yes

Yes

Yes

Not evaluated

Yes

Yes

Yes

Total 4,4’-DDT

Not evaluated

Yes

No, greater

No, greater

Yes

Not evaluated

Yes

No, greater

No, greater


162



References

Burchard, H., and Baumert, H., 1998, The formation of estuarine turbidity maxima due to density effects in the salt wedge. A hydrodynamic process study: Journal of

Physical Oceanography, v. 28, p. 309-321.

Chant, R.J., and Stoner, A.W., 2001, Particle trapping in a stratified flood-dominated estuary: Journal of Marine Research, v. 59, no. 1., p. 29-51.

Geyer, W.R., 1993, The importance of suppression of turbulence by stratification on the estuarine turbidity maximum: Estuaries, v. 16, no. 1, p. 113-125.

New Jersey Department of Environmental Protection, 2001, New Jersey Toxics

Reduction Workplan (NJTRWP) and Standard Operating Procedures (SOP)

NJTRWP-01, Rev. 1.0, March 2, 2001: New Jersey Department of

Environmental Protection, 112 p.

New York/ New Jersey Harbor Estuary Program Final Comprehensive Conservation and

Management Plan, 1996: Trenton, N.J., New Jersey Department of Environmental

Protection, 25 p.

Schubel, J.R., 1968, Turbidity maximum of the Northern Chesapeake Bay: Science, v. 6, p. 1012-1015.

Stevens Institute of Technology, 2005, The New Jersey Toxics Reduction Workplan for

NY-NJ Harbor ambient monitoring of water quality within major tributaries & the estuary, Studies I-D and I-E, 2 nd

draft, 150p.

TAMS, 2005, Final data summary and evaluation report for the Lower Passaic restoration project, May 2005, prepared by TAMS for the New Jersey Department of

Transportation Office of Maritime Resources under Contract No. 2001-NJMR02,

310 p.

U.S. Environmental Protection Agency 1994, USEPA Method 1613: Tetra- through octa- chlorinated dioxins and furans by isotope dilution HRGC/HRMS: U.S.

Environmental Protection Agency Office of Water, EPA Report Number

EPA/821/B-94/005, 86 p.

Wilson, T.P., and Bonin, J.L., 2006, Concentrations and loads of organic compounds and trace elements in tributaries to Newark and Raritan Bays, New Jersey, U.S.

Geological Survey Scientific Investigative Report XX-XX. 520p

163

APPENDIX B Results of Cross-Channel Monitoring

APPENDIX B

Results of Cross-Channel Monitoring

Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Contents

Contents - Continued

Figures

Figures – continued

Figures – continued

Figures – continued

Figures – continued

Figures – continued

Tables

Tables – continued

Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Introduction

Background Conditions

Evaluation of Concentrations and Chemistry of Suspended

Sediment during Dredging

December 5

December 5 – p.m.

December 6 – a.m.

December 7 - a.m.

December 8

December 10

December 10 - a.m.

December 10 – p.m.

References

Related documents

Products

Support

APPENDIX B Results of Cross-Channel Monitoring

APPENDIX B

Results of Cross-Channel Monitoring

Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Contents

Contents - Continued

Figures

Figures – continued

Figures – continued

Figures – continued

Figures – continued

Figures – continued

Tables

Tables – continued

Results of Cross-Channel Monitoring During the Lower

Passaic River Environmental Dredging Pilot Program on the

Lower Passaic River, December 1 to 12, 2005

Introduction

Background Conditions

Evaluation of Concentrations and Chemistry of Suspended

Sediment during Dredging

December 5

December 5 – p.m.

December 6 – a.m.

December 7 - a.m.

December 8

December 10

December 10 - a.m.

December 10 – p.m.

References

Related documents

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