Monitoring the Long Term Stability of the Fresh Kills Landfill in New York City

The stability of many embankments on soft soils is typically assessed during construction by monitoring the behavior of key parameters through the installation of geotechnical instruments. The measurements from the instruments are typically presented in graphical form and then compared to the results from engineering analyses. This procedure generally works well if there are not a lot of instruments to be monitored, the stratigraphy and embankment configuration are relatively uniform, and construction occurs over a relatively short period of time thereby limiting the amount of analyses that need to be performed. However, for many large landfills over soft soils this procedure can be rather cumbersome because the subsurface conditions and side slopes are likely to change over time, many instruments are needed over a large area, and landfill construction may occur over many years. This paper presents a unique methodology that has been implemented at the Fresh Kills Landfill in New York City to rapidly assess the stability conditions of the landfill during construction based on the large number of installed instruments and computer engineering analyses.