Geotechnical Investigation for Wreck Pond Coastal Restoration Feasibility Study

Under an Indefinite Delivery Contract with the US Army Corps of Engineers (USACE), New York District, Princeton Hydro completed a hazardous, toxic, and radioactive waste (HTRW) and geotechnical investigation as part of a larger feasibility study to assess potential flood damage reduction and ecological restoration efforts for Wreck Pond.

Wreck Pond is a man-made coastal impoundment that was historically a coastal tidal inlet . Following Hurricane Sandy, there was interest in supplementing local efforts to reduce flooding impacts and restore the lake to a healthier condition.

The investigation included the progression of 10 water-borne borings within the main pond of the Wreck Pond system, including one in a tributary pond. The borings were progressed through accumulated sediment and into the underlying parent material. The borings were logged by Princeton Hydro geotechnical staff and samples were collected for later analysis in Princeton Hydro’s AASHTO-accredited and USACE-certified laboratory.

Samples were also forwarded to a subcontracted analytical laboratory for analysis of potential nonpoint source pollutants that could impact local ecological resources and final disposal, if dredging of sediment was completed. In the geotechnical laboratory, the samples were subjected to geotechnical indexing tests, including grain size, organic content, moisture content, and plasticity/liquid limits. For soil strength parameters, the in-field Standard Penetration Test (SPT) as well as laboratory unconfined compression tests were performed on a clay sample to provide parameters for slope stability modeling.