Most of the Fifth Avenue
area is flat and lies at 23 feet above sea level. There are a few
elevated portions of the site that rise between seven to 15 feet
above the 23 feet level. The most significant elevation, caused
by a bedrock outcrop, rises to 60 feet above sea level and forms
a steep rock face on the southwest portion of the Fifth Avenue area.
A geotechnical boring
program was conducted in the Fifth Avenue area for soil analysis.
The soil types found included Urban Land, which refer to soils that
have been significantly altered by filling, regrading, and construction
and Udorthents, which describe soils that are deep, well drained
soils that have been altered by cutting and filling. Specifically
the surface material consists of asphalt, gravel and concrete. The
fill material, which ranges from 0.5 to 5.0 feet in depth, includes
gray sandy silt, organic silt, or gray coarse to fine sands of varying
colors. Fine gravel, clay, mica and roots were also observed. No
erosion prone soils are present. The bedrock in the area is comprised
of dark gray, white and pink-banded gneiss. Due to the long history
of development and landfill, the soils in the Fifth Avenue area
have all been disturbed.
Ten shallow groundwater-monitoring
wells were installed for groundwater analysis. (The results are
listed in detail in Section 3.14 Hazardous Materials of the DEIS).
The depth of the groundwater ranged from 3.7 to 7.1 feet below the
surface, with water elevations varying from 23.82 feet. Groundwater
flowed towards the east and northeast. Groundwater in the Fifth
Avenue area is not used in the vicinity for either drinking water
or industrial purposes. The Fifth Avenue area is not floodplain
area, but is located within the Pine Brook Basin watershed.