Sault Ste. Marie MGP Sediment Remediation: A Public-Private ...
MGP 2012
Sault Ste. Marie MGP Sediment Remediation: A Public-Private Partnership Under the Great Lakes Legacy Act Ed Sloan Marquette, Michigan
Former Sault Ste. Marie MGP - 1937 • MGP Site • Hickler Bros. Foundry and Marine • Soo Warehouse
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MGP Gas Holder and Hickler Bros. - 1929
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Site Photo – Present Day
• • • •
MCM Marine Floating Dry Dock Soo Warehouse Hickler Brothers Foundry and Marine
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GLLA – St. Marys River Former MGP • Approximately 35,000 cubic yards of contaminated sediment • Primary contaminant of concern – Polycyclic Aromatic Hydrocarbons (PAHs) • Non-federal sponsor – Consumers Energy Company • Multiple potential sources of PAHs identified in AOC near the GLLA project site • Initial contaminated sediment removal conducted solely by Consumers Energy in 2005 (7,300 cubic yards removed) • Phase I GLLA removal completed in 2010 (7,800 cubic yards) • Phase II GLLA removal completed for 2011 (20,000 cubic yards)
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Project Stakeholders • Consumers Energy • U.S. Environmental Protection Agency (USEPA) • City of Sault Ste. Marie • Michigan Department of Environmental Quality (MDEQ) • Bi-National Public Advisory Council (BPAC) • Sault Tribe of Chippewa Indians • MCM Marine
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Sediment Investigation (2001 through 2009)
Barge Mounted Drill Rig Vibracore and Ponar
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On-Shore MGP Remediation Tar Tank Demo
Separator Tank Demo
Pier Demo, Re-Design, and Construction
Shoreline Restoration
Sediment Removal Design and Support Activities • Geotechnical Evaluations • Structural Stability Modeling and Monitoring • Dredging effect on existing structures • Temporary Shoring Design and Monitoring • Conventional and Hydrographic Surveyors and Vessels • Geographic Information System Specialists
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Phase I GLLA Sediment Removal (2010)
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Phase I GLLA Sediment Removal (2010) Modified Clamshell Bucket
Containment Pad
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Phase I GLLA Sediment Removal (2010)
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Phase I GLLA Sediment Removal (2010)
Turbidity Curtain and Oil Boom (Native Clay Layer)
Background Turbidity of St. Marys River 0 to 5 NTUs
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Phase I GLLA Sediment Removal (2010)
Water Treatment - Frac Tanks - Bag Filters - Organo-Clay - Tri-Carb - 2 Canister Carbon Polish - Discharge to Sanitary Sewer
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Clean-up Criteria Development • Over 100 sediment sample locations (Surface and Cores) within the dredging footprint • Began with evaluation of historical PAH (16) data [22.8 ppm Total PAHs – MacDonald 2000, Probable Effects Concentration (PEC)}. • Gathered additional samples for analysis of PAH (16), PAH (34), and Pore Water (University of North Dakota Lab). • Conducted a statistical analysis of data to derive clean-up criteria applicable to the site (115 ppm total PAH 16 – less than 1 toxic unit). • Utilized multiple lines of evidence (visual contamination, thick soft sediment deposits, pore water PAH data, whole sediment PAH data) to propose the final dredging outline.
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Phase II Sediment Removal - Area Based on TU>1, PAHs >115 ppm, Visible, and Soft Sediment
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Phase II GLLA Sediment Removal (2011) • • • •
Federal Navigation Channel River Current and Level Changes Ship Traffic Working Dry Dock and Marine Contractor
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Phase II GLLA Sediment Removal (2011) Offloading to Containment Pad Hopper Barge
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Phase II GLLA Sediment Removal (2011)
• 12 CUYD Cable Arm • Dredging to Hopper Barge
Truck Loading (Sediment Dried with Lime and Sawdust)
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Verification Sampling and Residual Cover
• Over 50 verification samples were collected in the dredge footprint • Samples verified that soft sediment was removed to the target native clay layer • Areas with PAH levels above clean-up targets received residual sand cover
Page 22
Water Treatment
Thank You
Edward J. Sloan Senior Project Manager 906-226-4983 [email protected]
Sault Ste. Marie MGP Sediment Remediation: A Public-Private Partnership Under the Great Lakes Legacy Act Ed Sloan Marquette, Michigan
Former Sault Ste. Marie MGP - 1937 • MGP Site • Hickler Bros. Foundry and Marine • Soo Warehouse
Page 2
MGP Gas Holder and Hickler Bros. - 1929
Page 3
Site Photo – Present Day
• • • •
MCM Marine Floating Dry Dock Soo Warehouse Hickler Brothers Foundry and Marine
Page 4
Page 5
Page 6
GLLA – St. Marys River Former MGP • Approximately 35,000 cubic yards of contaminated sediment • Primary contaminant of concern – Polycyclic Aromatic Hydrocarbons (PAHs) • Non-federal sponsor – Consumers Energy Company • Multiple potential sources of PAHs identified in AOC near the GLLA project site • Initial contaminated sediment removal conducted solely by Consumers Energy in 2005 (7,300 cubic yards removed) • Phase I GLLA removal completed in 2010 (7,800 cubic yards) • Phase II GLLA removal completed for 2011 (20,000 cubic yards)
Page 7
Project Stakeholders • Consumers Energy • U.S. Environmental Protection Agency (USEPA) • City of Sault Ste. Marie • Michigan Department of Environmental Quality (MDEQ) • Bi-National Public Advisory Council (BPAC) • Sault Tribe of Chippewa Indians • MCM Marine
Page 8
Sediment Investigation (2001 through 2009)
Barge Mounted Drill Rig Vibracore and Ponar
Page 9
On-Shore MGP Remediation Tar Tank Demo
Separator Tank Demo
Pier Demo, Re-Design, and Construction
Shoreline Restoration
Sediment Removal Design and Support Activities • Geotechnical Evaluations • Structural Stability Modeling and Monitoring • Dredging effect on existing structures • Temporary Shoring Design and Monitoring • Conventional and Hydrographic Surveyors and Vessels • Geographic Information System Specialists
Page 11
Phase I GLLA Sediment Removal (2010)
Page 12
Phase I GLLA Sediment Removal (2010) Modified Clamshell Bucket
Containment Pad
Page 13
Phase I GLLA Sediment Removal (2010)
Page 14
Phase I GLLA Sediment Removal (2010)
Turbidity Curtain and Oil Boom (Native Clay Layer)
Background Turbidity of St. Marys River 0 to 5 NTUs
Page 15
Phase I GLLA Sediment Removal (2010)
Water Treatment - Frac Tanks - Bag Filters - Organo-Clay - Tri-Carb - 2 Canister Carbon Polish - Discharge to Sanitary Sewer
Page 16
Clean-up Criteria Development • Over 100 sediment sample locations (Surface and Cores) within the dredging footprint • Began with evaluation of historical PAH (16) data [22.8 ppm Total PAHs – MacDonald 2000, Probable Effects Concentration (PEC)}. • Gathered additional samples for analysis of PAH (16), PAH (34), and Pore Water (University of North Dakota Lab). • Conducted a statistical analysis of data to derive clean-up criteria applicable to the site (115 ppm total PAH 16 – less than 1 toxic unit). • Utilized multiple lines of evidence (visual contamination, thick soft sediment deposits, pore water PAH data, whole sediment PAH data) to propose the final dredging outline.
Page 17
Phase II Sediment Removal - Area Based on TU>1, PAHs >115 ppm, Visible, and Soft Sediment
Page 18
Phase II GLLA Sediment Removal (2011) • • • •
Federal Navigation Channel River Current and Level Changes Ship Traffic Working Dry Dock and Marine Contractor
Page 19
Phase II GLLA Sediment Removal (2011) Offloading to Containment Pad Hopper Barge
Page 20
Phase II GLLA Sediment Removal (2011)
• 12 CUYD Cable Arm • Dredging to Hopper Barge
Truck Loading (Sediment Dried with Lime and Sawdust)
Page 21
Verification Sampling and Residual Cover
• Over 50 verification samples were collected in the dredge footprint • Samples verified that soft sediment was removed to the target native clay layer • Areas with PAH levels above clean-up targets received residual sand cover
Page 22
Water Treatment
Thank You
Edward J. Sloan Senior Project Manager 906-226-4983 [email protected]
