Region 2 serving the people of New Jersey, New York, Puerto Rico and the U.S. Virgin Islands

3/14/2016

RECORD OF DECISIONFOR THE LOWER 8.3 MILES

OF THE LOWER PASSAIC RIVERPART OF DIAMOND ALKALI SUPERFUND SITE

CAG Meeting: March 10, 2016

Record of Decision (ROD) on March 4, 2016

• Engineered cap installed over lower 8.3 miles, bank to bank

• Before cap, dredge 3.5 million cubic yards of sediment

– To prevent cap from making flooding worse

– To accommodate continued commercial navigation in the lower 1.7 mi

• Dredged materials barged to processing facility on the banks of the Lower Passaic or Newark Bay

– To be dewatered � water squeezed out will be treated to standards

– To be transported off-site for disposal

• NJ’s prohibitions on fish and crab consumption remain in effect until risk-based goals are reached - with enhanced outreach

• Institutional controls in place to protect the cap

• Long-term monitoring and maintenance of the cap required

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Diamond Alkali Superfund Site:

Phased Approach to Cleanup

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Reminder: Why Clean Up the Lower 8.3 Miles?

• For Lower Passaic River, majority of contamination is found in the lower 8.3 miles

– Below River Mile 8.3: mostly silt with pockets of sand– Above River Mile 8.3: mostly sand with pockets of silt– 85-90% of fine-grained sediments are below River Mile 8.3

• Lower Passaic River is tidal

• Surface sediments suspend and move with tides twice a day (deeper sediments come up during storms)

• In lower 8.3 miles, contamination is everywhere, bank to bank at levels far above clean-up goals

• Contamination levels have declined very little in past 20 years

• Resuspension of sediment is the major on-going source of contamination

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People are eating fish and crab from the lower 8.3 miles

Risks related to eating fish/crab from the river are significant

Risks from exposure to contaminated sediment are significant for wildlife

Action is required to reduce these risks.

Risks from Contaminated Sediment

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Proposed Plan in April 2014

• EPA evaluated 4 alternatives:

1) No Action

2) Deep Dredging with Backfill

3) Capping with Dredging for Flooding

and Navigation

4) Focused Dredging and Capping

• Active alternatives have 3 disposal methods:

A. CAD (confined aquatic disposal) in Newark Bay

B. Off-Site Disposal

C. Local Decontamination & Beneficial Use

ActiveAlternatives

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From Proposed Plan to Record of Decision

• Proposed Plan public comment period: 4 months

• EPA received thousands of comments

• After the close of the comment period, as part of our consideration of and response to comments, EPA:

– Incorporated data collected after issuance of RI/FFS

– Updated and re-ran the model

– Updated risk assessment calculations

– Updated construction sequencing, schedule and costs

• Considerations for EPA during review of comments:

– Did comments significantly change the comparative analysis of alternatives presented in the Proposed Plan?

– Do we find that significant changes need to be made to the basic features of the remedy, as laid out in the Proposed Plan?

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ROD: Summary of Alternatives

AlternativesVolume Dredged

Construction

TimeDisposal Methods Cost

1) No Action N/A N/A None $0

2) Deep

Dredging with Backfill

9.7 million cubic yards

14 years

A) CAD $1.2 Bil

B) Off-Site Disposal $2.8 Bil

C) Decon/Beneficial Use $2.6 Bil

3) Capping w/

Dredging for

Flooding &Navigation

3.5 million cubic yards

6 years

A) CAD $0.9 Bil

B) Off-Site Disposal $1.4 Bil

C) Decon/Beneficial Use $1.4 Bil

4) Focused

Capping w/

Dredging for Flooding

1.0 million cubic yards

2.5 years

A) CAD $0.4 Bil

B) Off-Site Disposal $0.6 Bil

C) Decon/Beneficial Use $0.6 Bil8

Differences Between Proposed Plan and ROD

• Final plan removes 0.8 million cubic yards less material from the river than was proposed

– Less dredging will be performed in navigation channel

• Final plan will be easier to implement than what was proposed

• Final plan cost estimate is $350 million less than what was proposed

– Final plan = $1.38 million

– Proposed plan = $1.73 million

The final plan is as protective of human health and the environment as the proposed plan.

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Comparing Navigation Channel Depths

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Proposed Plan Navigation Channel

Selected Remedy

Navigation Channel

What Will the Engineered Cap Look Like?

• What EPA assumed in the ROD:

– 2 feet of sand

– If needed, 6 inches of stone to stabilize

– In mudflats, 1 foot of sand under 1 foot of habitat material

• During design, potential changes to the cap could include:

– Sand could be enhanced by carbon

– Sand could be thinner based on inclusion of synthetic materials

• Overall, the engineered cap must be protective, not increase flooding, accommodate anticipated future use, and in mudflats, restore habitat.

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Opening and Closing Bridges During Construction

Bridges over lower 8.3 miles will NOT have to be opened and closed regularly to let barges of dredged materials through.

13 bridges over lower 8.3 miles

• 1 span removed and 1 maintained in open position

• 9 bridges with vertical clearances greater than 20 feet

* Hudson River used low profile barges and tugs *

• For 2 bridges with vertical clearances less than 20 feet:

� Can pump dredged materials under bridges without opening them

May need to open bridges at the beginning and/or end of project to move big equipment through.

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Next Steps

• EPA negotiates with parties responsible for the contamination to seek their performance of or payment for the work

• Design of the cleanup activities could take 3 to 4 years

– During design, EPA will conduct public outreach on

• Location of sediment processing facility

• Quality of life standards

• How to minimize construction impacts

• Updating Community Involvement Plan

• Construction is expected to take 6 years

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