Remediation Work
(Remediation currently suspended for the demolition of 115 River Road)
Cleanup at the Quanta site began in 2016 using a process called in situ solidification (ISS). In the ISS process, cement is mixed with the contaminated soil using an auger or excavator bucket. The mixed material hardens into a solidified mass, locking up arsenic, coal tar, and waste oil, and preventing groundwater from moving through it. The work consists of:
- Mobilization and setup
Locating temporary construction facilities, repairing and upgrading the fence, and clearing vegetation above grade. - Site clearing, debris removal, and demolition
Completing construction of temporary facilities, removing debris, vegetation, and pavement that will interfere with site work and demolishing the concrete wharf at the Quanta property shoreline. - Installation of a steel sheet pile bulkhead
To protect the Hudson River, a steel sheet pile bulkhead is being installed along a 730-foot section of shoreline. - Implementation of full-scale soil solidification
Approximately 150,000 cubic yards of soil is being treated using soil solidification. Cement and slag is mixed with the soil using an auger or excavator bucket. The mixed material hardens into a solidified mass, locking up arsenic, coal tar, and waste oil, and prevents groundwater from moving through the contaminated soil.
NorthStar - Soil Solidification Contractor
NorthStar was selected from a list of EPA-approved contractors for this project to conduct the soil solidification remedy. The company, one of the largest remediation contractors in the nation, with revenues over $650 million in 2015, has a strong safety record and numerous National Safety Council awards. NorthStar also has been recognized by EPA for its greenhouse gas emission reduction, waste reduction, recycling, and local economic impacts.
Successful Field Demonstration Completed in 2013
In 2013, a field demonstration test was completed to evaluate field conditions and potential challenges unique to the Quanta site before full-scale design and implementation of the soil remedy. The field demonstration test involved four areas of the site, each with distinct physical properties. Results demonstrated that the treatment was effective and successfully met the EPA standards, with no exceedances of air quality standards.
Construction of Groundwater Remedy
The groundwater remedy, which involves installing a subaqueous reactive barrier along the shoreline of the river, will be completed separately. This permeable reactive mat will be placed on top of underwater sediments, and will remove contaminants from groundwater as the groundwater flows through it. Detailed design of the groundwater remedy is currently underway, and it will be implemented in conjunction with the river sediments work.
Drinking water in Edgewater comes from four reservoirs - the Oradell, Woodcliff Lake, and Lake Tappan reservoirs in Bergen County, New Jersey, and Lake DeForest in Rockland County, New York. These reservoirs are not affected by groundwater at the Quanta site.
Operable Unit 2 (OU2)
The offshore portion of the site, including surface water and sediment in the Hudson River, is known as OU2. Investigation and remedial design for the cleanup of OU2 is occurring separately from the soil cleanup on land.
