The U.S. Fish and Wildlife Service (USFWS) contracted EA to assess the vulnerability of the USFWS Sachuest Point National Wildlife Refuge Remediated Landfill located in Middletown, Rhode Island to coastal storm events. Individual tasks that comprised this project included:
- A desktop review of the available data related to the physical setting, history of operation and closure, past storm damage, etc.
- An analysis of landfill cap susceptibility through wave runup modeling
- Conceptual plans for the short-term protection of the landfill – defined by USFWS as 0‑50 years
- Conceptual plans for the long-term protection of the landfill – greater than 50 years.
Data such as bathymetry, topography, tidal data, existing sea level elevations, storm surge and sea level rise predictions, and historic nearshore wave heights were obtained as inputs for the modeling effort associated with the final Resiliency Assessment Report. Two levels of modeling were performed: coastal storm surge modeling, using the Federal Emergency Management Agency program WHAFIS, and overland wave modeling, using the Federal Emergency Management Agency program RUNUP. The 100-year storm characteristics predicted by North Atlantic Coast Comprehensive Study for present day were applied to four sea level rise projection dates. Several alternatives were explored for short-term landfill protection design to address vulnerability of the Landfill while it remains in place. Conceptual designs, engineering opinions of cost, and construction sequencing were developed for articulated concrete block matting and the relocation of Sachuest Point Road combined with a dune construction design.