Fox River Cleanup Operable Units 2 - 5

Fox River Cleanup

• Total river 39 miles long, OU 2 – 5 is about 13 miles• PCB contamination • Combined Remedy:

• Prospective dredge volume ~4.0 MM cy• Prospective capping area > 500 acres• Monitored natural recovery in OUs 2 & 5

• Estimated remedial action duration = 8 years• Fox River Cleanup Group:

• Tetra Tech (Main Contractor)• J.F. Brennan (Marine Contractor)• Stuyvesant E.CO (Processing Contractor)

Green Bay, Wisconsin

Fox River Cleanup

• Sediment Characterization• Debris Removal• Cultural Resources• Dredging• Capping & Sand Cover• Sediment Separation• Mechanical Dewatering with Membrane Presses• Water Treatment• Beneficial Re-use & Upland Disposal• Monitored Natural Attenuation

Fox River

Process Plant Design

• Plant Designed and Constructed in one year! effective coordination with Agency Oversight Team

• Treatability Tests Performed• Aim is volume reduction by

beneficial use (sand separation) and mechanical dewatering

• Production Rates 250 in-situ CY per hour or 6500 GPM @ ~ 15% dry solids

• 4 dewatering ‘trains’ each with one pre-thickener tank, one buffer tank and 2 membrane plate and frame presses

Fox River Cleanup

One 12” Hydraulic Dredge, Two 8” Hydraulic DredgesDirect Feed to the Processing Plant (from 10 boosters over 10 miles of HDPE pipeline)

Processing Facility

Fox River Cleanup

1. Oversize Separation

2. Slurry Thickening

3. Sand Separation

4. Dewatering

Sand Separation

• Sand Separation for Beneficial Re-use• Two Sizes of Sand are separated

1. Fine sand (< 63-150um)

2. Coarse sand (150um – 6mm)

• Three Steps:

1. Hydro Cyclones

2. Upstream Classifiers

3. Dewatering Screens

• Sand meets Residential Standards

Fox River Cleanup

1. Polymer Dosing

2. Pre-Thickening

3. Buffer Tank

4. Mechanical Dewatering

Membrane Plate & Frame Presses

3 steps: filling chambers, pressing, discharging filter cake

Production: 8 - 12 Ton/hr (Dry Solid / Press)

188 Plates of 2 by 2 meters, automated cleaning system

Transport and Disposal

• Average ~ 53% DS dewatered filter cake

• TSCA / Non TSCA pre-determined• Truck Scales at the processing

Facility• Truck Wash• Focus on Safe Transport to the

Landfill

Evaluation of Performance

• First Season: May 2009 – November 2009• 460,000 CY planned to be processed in first season• Actual processed: 541,000 CY• ~ 30% sand recovered, all meeting residential standards• No lost time injuries

• Second Season (2010): Currently over 500,000 CY• Incorporated “lessons learned” from first season as part of

“Adaptive Management”• Value Engineering = Shared Savings

Boskalis Dolman bv

P.O. Box 76

3350 AB Papendrecht

The Netherlands

www.boskalisdolman.com

Stuyvesant Environmental Contracting Inc

3525 N. Causeway Blvd – Suite 612

Metairie, LA 70002

United States of America

www.stuyvesantenvironmental.com