1

James Hahnenberg

June 22, 2005

2

Todays discussion1. Tittabawassee & Fox rivers

2. Fox river cleanup activities (today: upriver focus)

3. Dredging issues and cleanup options

4. Cleanup economics

3

Fox and Tittabawassee

15

7

0

2

4

6

8

10

12

14

16

0

500

1000

1500

2000

2500

Depth (feet) Water velocity (ft3/sec)

Fox Tittabawasee1 Fox Tittabawasee

23302 23532(6 - 24)

(3 - 11)

1Midland to the Saginaw River (Saginaw River is up to 28 feet deep)

2Upstream

4

(Dioxin)

(PCBs)

Tittabawassee

Fox

5

Fox River PCBs: from papermills

Modified from Green Bay Press Gazette

6

PCBs can PCBs can get into get into your bodyyour body

7

Fox fish advisories

8

Fox River progress1. State & federal studies – 1990’s

2. Superfund studies: 1998

3. Dredging demos: 1998-2001

4. Cleanup proposal: 2001

9

Fox River progress5. Cleanup decisions: 2002 &

2003 by EPA and WDNR

6. Upriver dredging begins: 2004

7. Upriver completion: 2010

8. Downriver completion: 2018

10

Lower Fox River Dredging projects

Winnebago Calumet Manitowoc

Outagamie Brown

MILES

Deposit N(1998-1999)

SMU 56/57(1999-2000)

11

Clay & siltysediment

BedrockMaterial under contamination

$17,000,000 by companies

$4,000,000 by WDNR

Costs

80,000**8000*Volume removed (cubic yards)

1999-20001998-1999Years

SMU 56/57(downriver)

Deposit N(upriver)

Fox River dredging demonstrations

*Football field – 5’ high **Football field – 5 stories high

12

Dredging projects Achievements

1. Removed 2200 pounds of PCBs

2. PCB concentrations reduced (where no bedrock)

3. Negligible PCB loss to air and water

13

Dredging projects Achievements

4. Minimal community disturbance(e.g., noise, odors, traffic, etc.)

5. Developed working relationship with companies and communities

6. Showed dredging works

14

Fox River cleanupdecisions

Dredging/disposal –7.2 million cubic yards

Total cost: $400 million(dredging $350 million)

Monitored Natural

Recovery

Upriver work

started 2004

15

Fox Cleanup Decision• Reduce risks

• Mixture of cleanup options1. Dredging/disposal2. Capping3. Natural recovery

• Practical and flexible

16

OU 2: Monitored Natural Recovery

Upriver cleanup

17

Monitored Natural Recovery (OU 2)

1. PCB burial, dilution, or breakdown from biological activity

2. Monitoring to track “recovery”

18

0.3% (OU2)

3%6%

91%

OU1 (upstream)

OU4 (downstream)

PCBs by river segment(pounds)

OU3

19

Fox River PCB concentrations

3.02.10.23.7

Average

Surface average

Average1

61

204

41

53

17

521

28Water (ppt)

15Sediments (ppm)

Operable UnitMedia

1 All depths Sediment goal: 0.25 ppm

20

Lower Fox River side view profile

OU1 Little Lake Butte

des Mort

OU2 Appleton to Little Rapids

OU3 Little Rapids toDe Pere

OU4De Pere toGreen Bay

OU5Green Bay

OU 2 - steep slope (thin sediment - faster flow)

21

Monitored Natural RecoveryOU 2

1. Relatively small PCB mass

2. Lower PCB concentrations

3. Bedrock

4. Lots of dams (difficult access)

22

Upriver dredging

Started September 2004

23

1. Dredge sediments(800,000 cubic yards*)

2. Separate water from dredge slurry

3. Treat dredge water

4. Dispose at landfill

Upstream cleanup

2005dredging

*Football field – 50 stories high

24