TranSystems Corporation - LGM Construction

Our field engineer removed the samples from the sampling tools and visually classified
them. The undrained shear strength of representative cohesive samples was estimated
using either a hand-held pocket penetrometer or a Torvane shear device. Penetrometer
and Torvane readings are noted on the boring logs. Note that the pocket penetrometer
readings shown on the boring logs show unconfined compressive strength in units of
tons per square foot (tsf). This value is equivalent to undrained shear strength (Su) in
units of kips per square foot (ksf). The Torvane readings shown on the logs are
undrained shear strength readings converted to units of ksf. Soil samples retrieved
during our subsurface exploration were packaged and transported to our laboratory for
further evaluation and testing.
2.3 DEPTH TO GROUNDWATER MEASUREMENTS
As both borings were drilled using the rotary wash drilling method, which employs
constantly circulating drilling fluid, ground water levels could not be measured, so we
advanced a third boring to 12 feet bgs, immediately adjacent to boring KB-2.
First encountered free groundwater was at observed 12 feet bgs, immediately following
drilling, and then at 10 feet bgs after approximately 10 minutes. Depth-to-water
measurements are noted on the boring logs. Because groundwater levels had to be
measured soon after completion of the borehole, the levels recorded likely do not
represent stabilized groundwater. Stabilized groundwater levels are discussed in
subsequent sections of this report.
2.4 EXPLORATION COMPLETION AND ABANDONMENT
In accordance with the conditions of our drilling permit, we backfilled the open boreholes
with cement grout, and patched the asphalt pavement with temporary cold-patch
asphalt. We placed drill cuttings and fluid into 55-gallon steel drums for pickup and
disposal by a specialized disposal subcontractor.
94240/1(OAK8R061)/es Page 4 of 29 June 13, 2008
© 2008 Kleinfelder