1. Complex Estuarine Dynamics
Estuarine circulation can transport downstream pollutants to upstream

2. Pollutants in the James River can be transported into the Elizabeth River

3. Pollutants in the Elizabeth River can be transported to James River

4. Pollutant Sources from Watershed

5. PCB Transport in Estuary
Atmospheric
depostion
Air-sea
exchange
Runoff
Discharge
Sorbed to
POC & algae
PCB
Transport downstream
Sorption/desorption
Sorbed
to DOC
Dissolved
Settling and
Resuspension
Transport
Upstream due to stratification
Ground
water
Diffusion
Burial

6. Modeling Approach Entire James River will be simulated
Refined model grids will be used whenever it is needed
An equilibrium sorbent dynamic PCB model will be incorporated into the hydrodynamic model for simulation PCB transport in the estuary

7. Modeling Framework Hydrodynamic Model Eutrophication Model
Transport fields
Mixing
Eutrophication
Model
Organic carbon in water column
Organic carbon in bottom Sediment
point/nonpoint sources
Sorbent dynamic PCB model
(equilibrium partition)
Atmospheric deposition
Diffusion
PCB in water
PCB in sediment
deposition
resuspension
Net burial

8. James River Model Grid

9. Example of Refined Elizabeth River
This slide shows the transition from coarse grid (370m cells) to fine grid (123m cells) in the Elizabeth River where the effects of channel deepening were investigated. In addition to channel deepening, the evaluation of design effects on material transport and the flushing ability of the Elizabeth River basin was evaluated. Neither would have been possible in the absence of the fine grid.