1. The Hudson River PCB Problem
Ben Jewell
Przemyslaw Bosak

2. PCB Intro Molecular structure: Characteristics Sources Disposal
Two benzene rings linked by a single bond
Chlorine replacement of some Hydrogen atoms
Characteristics
Nearly insoluble in water
Difficult to burn
Low vapor pressure
Good electrical insulators
Sources
Synthetic, used as a coolant fluid
US production ended in 1977, still in use in transformers
Disposal
Incineration

3. PCBs in the Environment
Where does it go?
Deposition in river/lake sediments
Enters food stream, bio accumulation
Volatilization
Life span
Do not readily degrade
Can exist in environment for decades

4. PCB Health Effects Not acutely toxic to humans Chloracne Cancer
most common sympton of organochlorine exposure
Disfiguring, painful analog to acne
Cancer
the types of PCBs likely to be bioaccumulated in fish and bound to sediments are the most carcinogenic PCB mixtures
found through animal and exposure studies
Immune System
increasing risk of non-Hodgkins lymphoma
Neurological
learning deficits and changes in activity associated with exposures to PCBs
most strongly associated with newborn children
Reproductive
decreased birth weight
significant decrease in gestational age
Exposure studies

5. Hudson River History General Electric: 1950s, 60s and 70s Uses
Capacitors, power transformers
Discharge
Two capacitor manufacturing plants released between 209,000 and 1.3 million pounds
Leaking devices

6. Clean Up Efforts Past Clean up
Dredging of 180,000 cubic yards of contaminated sediments in
Capping of remnant deposits with a geosynthetic clay liner and a 2-foot layer of soil,
Stabilization of river banks with rock
Continuous monitoring of PCB level in the river

7. Hudson River Now Peak PCB level in 1991
Clean up efforts lowered the concentration of PCB in the water and have kept it at pre-1991 level
Catch-and-release fishing allowed

8. What is next?
Dredging of 2.65 million cubic yards of PCB-contaminated sediments using environmental techniques to minimize resuspension of sediments
Covering dredged areas with one foot of clean soil to isolate residual PCBs
Restoration of aquatic vegetation
Monitoring system recovery

9. Aquatic Chemistry Implications
Dredging
Disruption to aquatic system
Increased turbidity
Release of trapped minerals and nutrients
Bioaccumulation effects on river fauna
Hazardous to health

10. Thank you for listening, we will now take any questions