ETL 1110-1-171
31 Jan 96
investigated to some extent and will have boring information.
Military HTRW sites will have construction boring information
which can be accessed. Soil classification by cone penetrometer
testing (CPT) and factors affecting CPT results have been
established empirically and discussed in the literature. Several
references are provided in paragraph 3.
(2) Sensor Validation: The LIF sensor responds to
polynuclear aromatic hydrocarbons and was designed to detect
petroleum/oil/lubricants (POLs). Laboratory and field validation
experiments have been performed on a number of samples.
Comparisons have been made between the LIF response and
conventional analytical methods. Available chemical data
indicate that the LIF sensor equipped with the nitrogen laser
(excitation wavelength of 337 nm) can detect diesel, heavy weight
fuel oils, and coal tar derivatives at relatively low
concentrations and gasoline and JP4 at relatively high
concentrations or as pure products. The tunable dye laser
(excitation wavelength of 290 nm) is more capable of detecting
the lighter or more volatile fuels than the LIF probe equipped
with the nitrogen laser, although only limited field tests have
been conducted. Preliminary detection limit determinations have
indicated response is influenced by soil type and other matrix
effects. Additional validation work is in progress and is
planned for the future. Reports on this work will be available
periodically.
Field Applications:
k.
(1) SCAPS can be used anywhere static direct push is
feasible. A static direct push method is most suited for fine
grained unconsolidated materials including sands, silts and clays
which are typically found in recent flood plains, coastal plains,
and lake beds. Unconsolidated Pleistocene and Tertiary deposits
corresponding with the environmental settings listed above are
also suitable as is eolian loess. In some areas where hard
surficial materials are found, it may be possible to pre-push
holes with non-instrumented probes prior to using a sensor probe.
Although geotechnical data cannot be obtained with this approach,
it does allow sensor probe data (e.g., LIF) to be obtained while
minimizing the risk of damage to the sensors.
(2) The LIF sensor can be used on sites where petroleum
hydrocarbons are expected to be contaminants. These sites
include fuel storage areas, refueling stations, former
manufactured gas plants, air base flight lines, fire training
areas, fuel pipelines, fuel spill areas, and vehicle maintenance
shops. The use of the LIF sensor to delineate in-situ
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