Lipari Landfill Superfund Site Remediation
Pitman, New Jersey
Date of Execution: March 1994
Significant Project Features:
- Value Engineering Change Proposals resulted in cost savings of $3.35 million and schedule reduction of one year.
- Wetlands excavation of over 150,000 cubic yards, including Chestnut Branch Marsh and Alcyon Lake bed.
- On-site low-temperature thermal treatment of 60,000 cy of VOC-contaminated Marsh sediments.
- 320,000 man-hours worked with zero incidents, accidents or lost time injuries.
History and Location of Project
The 16-acre Lipari Landfill Site, in Gloucester County, New Jersey, was once ranked the No. 1 Superfund site in the nation. Originally the location of a sand and gravel pit, the site came to be used as an unregulated dump for municipal and industrial wastes of every type.
Prior to Sevenson's involvement, the USEPA conducted Interim Remedial Measures (IRMs) at the Lipari site. Earlier remedial measures included the installation of a liner cover and slurry wall enclosing the landfill and a leachate treatment system. The persistence of odors following these measures led USEPA to conclude that further remediation, this time in offsite areas, would be necessary.
Description of Work
Sevenson was contracted to excavate and treat contaminated soils and sediments from Alcyon Lake and associated marsh and stream areas adjacent to the Lipari Landfill and restore these areas to natural conditions. All work was conducted under U.S. Army Corps of Engineers and USEPA Region II oversight.
The project was defined in three task areas:
Site Preparation - including installation of 1.5 miles of double-wall HDPE force main, complete with electronic leak detection; over 2 miles of temporary haul roads, including stream crossings; diversion of Chestnut Branch; and construction of soil erosion and sediment control measures over a 25-acre area.
Chestnut Branch - Excavation of 60,000 yd3 of VOC-contaminated soils from the 14-acre marsh areas using specialty amphibious excavating and hauling equipment designed and built by Sevenson. These soils were treated using low temperature thermal desorption then placed in an on-site cell. The wetlands areas were restored to natural conditions with native tidal marsh vegetation; and a drain bordering the marsh was installed to protect off-site areas from re-contamination from the adjacent Lipari Landfill.
Alcyon Lake - Installation of a surface water bypass channel, diversion berms, and floating haul roads on the exposed lake surfaces, followed by excavation of 85,000 yd3 of contaminated lake sediments. Sevenson reconstructed the lake to depths and contours in accordance with USACE guidance specifications.
Acceptance of Value Engineering Change Proposals (VECPs) by the owner, USACE, and USEPA served to reduce project costs and compress the schedule. VECPs included:
- Redesigned site diversion channels and haul roads, and eliminated temporary bridges to simplify on-site traffic patterns and maximize productivity in materials handling.
- Used open-space clam structures in lieu of pre-engineered metal buildings at lower cost and improved safety measures.
- Eliminated concrete storage pads and cast-in-place walls, replacing them with asphalt pads and Jersey Barriers for added flexibility in materials management.
- Redesigned the Alcyon Lake dewatering/pumping method using a combination of pumping and gravity flow resulting in greater control of water flows, which was critical to minimizing construction water requiring on-site water treatment.
- Modified the Marsh Restoration Plan to allow use of a greater volume of lower elevation plantings, resulting in a more emergent wetlands which has experienced minimal mortality. As part of this project, Sevenson constructed a drain and slope cap, relocated a municipal sewer line, and landscaped the site. All work was completed on schedule and below budget.
Health and Safety Overview:
- Unique Characteristics: Since this project involved work with volatile and semi-volatile organic compounds and inorganic metal wastes; continuous real time air monitoring and site perimeter monitoring was performed for the protection of the on-site workers and neighboring persons and residences. All workers wore PPE when working in the exclusion zone, ranging from Level D to Level B PPE. The perimeter air monitoring system was set up to continuously monitor the output from the thermal treatment system and to ensure no off-site migration of VOCs and Semi-VOCs during excavation and staging operations.
- Health and Safety Measures: Real time air monitoring was performed with HNU's, Sibata dust monitors, and oxygen and combustible gas indicators for all work inside confined spaces. Perimeter air monitoring was required to ensure that operations were not allowing off-site migration of dusts and volatiles above site action limits. A state-of-the-art Fourier Transform InfraRed (FTIR) continuous air monitoring system was employed at the marsh excavation areas.
- Health and Safety Staff: One full-time Site Health and Safety Officer and three Safety Technicians were responsible for daily operations. Dr. Paul Hitcho, Corporate Director of Safety and Health, was responsible for the development and oversight of the health and safety plans. The SSO implemented the day-to-day operations for the SSHP. The technicians were responsible for the calibration and proper use of the air monitoring instrumentation, performing the air monitoring and reporting to the SSO any problems or deficiencies.
How 40-Hour Training Was Implemented: Sevenson personnel are trained in-house. Union personnel are provided with training and updates through the hall.