Industrial
| Project | Cell 6 -2A, Environmental Cap Phase II and Gas Collection System |
| Client | Waste Management (DRPI) |
| Design Professional | Geosyntec |
| Location | New Castle, DE |
| Job Size | $1 – 3 Million |
| Duration | 8 months |
| Date of Completion | October 2013 |
Project Overview
Project consisted of installation of new twelve acre landfill cell adjacent to operating cell of existing landfill, including two foot drainage layer of rice gravel. The cell received a gas collection system below the primary liner due to existing waste in area (gas wells, vertical and horizontal conduit). An environmental cap was also placed outside of the cell extents which received two feet of protective cover soil. The landfill gas was tied into the existing LFG loop at the landfill, with connections for future collection points from the waste.
- Installed and maintained E&S controls for 20+-acre area.
- Unloaded and stored geosynthetic liner materials (HDPE, GCL, Composite, Non-Woven)
- per DNREC and ASTM standards.
- Completed fine grading and fill placement for 12-acre cell subgrade.
- Excavated and backfilled 3,000+ linear feet of anchor trench.
- Maintained and installed additional E&S controls.
- Imported and placed 40,000 CY of protective drainage layer (rice gravel) on geosynthetic liner system.
- Work performed utilizing GPS technology on grading equipment within 0.1’ tolerance.
- Installed 2,200 LF of perimeter roadway and water channel.
- Installed 230 vertical feet gas conduit.
- Installed 170 vertical feet gas well.
- Installed 2,400 LF of gas collection trench, well heads including liner boots.
- Installed 2,800 LF of 12” HDPE LFG header.
- Installed 1,250 LF of perforated HDPE leachate collection corridor.
- Installed gas condensate sump, controls and valves.
- Installed 1,300 LF of dual contained leachate force main from gas condensate sump
- Graded for (6) acres of environmental cap.
- Placed 16,500 CY of protective cover soil on environmental cap.
Key Challenges
Coordination of the cell construction with landfill operations (tie-in’s, erosion from existing cell etc.) Import of 25,000+ CY of structural fill and 40,000+ CY of protective drainage layer material from one entrance and working on low area of cell during a period of significant rain events. Tie-in and installation of Gas Force Main and Leachate Force Main as the new cell was being filled with waste.