Expedited Remediation of Coal Tar Containing Sediments: Design-to-Build Approach with a Beneficial Reuse

Transcription

1 Expedited Remediation of Coal Tar Containing Sediments: Design-to-Build Approach with a Beneficial Reuse Mike Crystal Sevenson Environmental Services Kurt Paschl Beazer East Inc. Alan Fowler ARCADIS Presentation Overview Site Setting Design-to-Build Approach Design Details Construction Beneficial Reuse Lessons Learned 2

2 Former Coal Tar Processing Facility Site (also known as the Island End River Site) Located near Boston Harbor 10 acres within a larger 200-acre area that also included: A coke plant A manufactured gas plant Related operations Approximately 130,000 cubic yards (cy) of NAPLcontaining sediment 3 What Made this Project a Challenge Multiple PRPs Complicated surface water/groundwater interaction Sediment remediation driven by observations of sheen Project highly visible with Regulators Local community Adjacent marina The need to complete construction during a single season 4

3 Island End River and the FCTPF Site IMC Building Beacham Street N Market Street Boston Fruit Auction Building Northern Mudflat Area W E S Eastern Mudflat Area RAM Area FCTPF Boundary Barge Channel Federal Channel High and Low Water Lines Mean High Water (El. 5.1 ft) Mean Low Water (El ft) Feet 5 Primary Aquatic Environmental Issue: Sediment Generated Sheens 6

4 Primary Upland Environmental Issue: Potential NAPL Migration 7 Design-to-Build Project Approach Client-assembled project team (clients include Honeywell International, National Grid and Beazer East Inc.) Team members selected based on their technical expertise and past performance in similar situations Team members include: ARCADIS: Project management and engineering design Sevenson: Constructability review and construction Other specialty subcontractors for structural steel design, noise monitoring and permitting support Team motivated to act as one team 8

5 Site-Specific Pilot Dredging Study Developed by the designto-build team to answer key design/permitting questions Completed in 2005 and streamlined the design and permitting process Provided quantitative answers to questions asked by both the permitting agencies and local stakeholders 9 State Approved Remedy after Pilot Study In-place isolation of 60,000 cy of sediment within the footprint of a shoreline Confined Disposal Facility (CDF) Dredging of approximately 70,000 cy of sediment with disposal of 50,000 cy in the on-site CDF 20,000 cy of sediment disposed at an off-site landfill (transported via rail and truck) CDF is an integral part of upland migration barrier isolating upland portions of the Site from the River 10

6 CDF Location and Dredging Area 11 CDF Footprint and Dredge Prism 12

7 CDF Details Areas with Concrete and Asphalt Decking CDF Details Section In Concrete Deck Area 14

8 Permitting Process Completed within 18 Months and in Parallel with the Project s Design Complex permitting process included: Five separate federal and state agencies Two municipalities Coastal Beach (Tidal Flat) Regular communication with permitting agencies was important both prior to and during construction 15 Building Local Support During Permitting Process Navigational Dredging of Local Marina 16

9 Area Drainage Improvements Part of Obtaining Local Approvals 17 Steel Fabrication Begins January 2006 in Advance of Final Permits 18

10 Spring 2006 Construction Begins 19 High Level of Uncertainty for Existing Shoreline Conditions 20

11 Template used to Set CDF Alignment 21 Parallel Construction Operations Needed to Meet 1-Year Construction Schedule 22

12 Safety was a Core Project Value 23 Stabilizing Sediment Behind the CDF Wall 24

13 Dredging with Barge-Mounted Excavator 25 Dredging in an Authorized Federal Channel Required Coordination with Many Parties 26

14 Post-Dredging Backfill Placement 27 CDF Constructed to Support Local Marine Business Interests 28

15 Lessons Learned Make safety a core value no significant worker safety issues with over 150,000 man-hours logged Design-to-build approach provides a flexible and cost-effective approach for sediment projects which contain a significant amount of uncertainty by their very nature Beneficial reuse can be an effective tool for moving similar projects forward especially when the projects are located in areas designated for port use or targeted for redevelopment Expect the unexpected, and plan for it schedule and budget requirements for this project were met despite challenges and changes 29 Lessons Learned (cont.) Recognize that some level of local outreach (local extractions) may be needed to make the project viable in the local community Client-assembled teams do work put the best team together irrespective of their organization and demand nothing short of a one team effort Permitting don t sit back, become an advocate with the permitting agencies and have the lead regulatory agency become a proponent for your project 30

16 Acknowledgements Honeywell International: John Morris and Tim Metcalf National Grid: Tracey Bell Beazer East Inc.: Kurt Paschl and Mike Bollinger 31