Challenge
The former Hi-Lo Cipriano Landfill in Johnston, Rhode Island encompasses approximately 13.6 acres. Landfilling operations were conducted at the property from 1967 to the late 1980s. The facility reportedly received approximately 35,000 tons of construction and demolition debris per year. The former Pocasset River channel extends through the landfill from northwest to southeast. The former river channel through the site is designated by Federal Emergency Management Agency (FEMA) as a floodway and Flood Zone AE, indicating an area that would be “inundated by the 1% annual chance flood.” The Site is also bordered to the north, south and west by the Pocasset River and its associated wetlands, which represent environmentally sensitive receptors in the area.
Solution
GZA completed the site investigation, FEMA Letter of Map Revisions to revise the delineation of the floodway and floodplain on the property, and design and permitting of the Site landfill closure. GZA designed the Site landfill closure system and remedial actions to integrate with the property’s planned mixed-use medical/commercial redevelopment. The Site remedy involved removal of landfill debris from wetlands; re-use of 60,000 CY of landfill debris on-site based on the Rhode Island Department of Environmental Management’s (RIDEM) Beneficial Use Determination (BUD); landfill redevelopment and landfill capping (geomembrane and geotextile barriers); creation of wetland habitat; and increase in floodplain storage capacity.
Benefit
GZA is the Engineer-of-Record for implementation of the landfill closure and remedial actions and Site development (geotechnical), and performed Construction and quality control services and geotechnical special inspections for building construction.
