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| Titel |
Detection of an organic-non volatile compound in variable-contaminated volcanic soil samples via Time Domain Reflectometry (TDR) technique: Preliminary results |
| VerfasserIn |
Alessandro Comegna, Antonio Coppola, Giovanna Dragonetti, Nesrine Chaali, Angelo Sommella |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250090781
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| Publikation (Nr.) |
 EGU/EGU2014-5038.pdf |
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| Zusammenfassung |
| Hydrocarbons may be present in soils as non-aqueous phase liquids (NAPLs), which means
that these organic compounds, exist as a separate and immiscible phase with respect to water
and air commonly present in the soil. NAPLs, which can be accidentally introduced in the
environment (for example by waste disposal sites, industrial spills, gasoline stations,
etc), constitutes a serious geo-environmental problem, given the toxicity level and
the high mobility. Time domain reflectometry (TDR) has became, over several
decades, an important technique for water estimation in soils. In order to expand the
potentiality of the TDR technique, the main objective of this study is to explore the
capacity of dielectric response to detect the presence of NAPLs in volcanic soils. In
laboratory, soil samples were oven dried at 105°C and passed through a 2 mm sieve.
Known quantities of soil, water and NAPL (corn oil, a non-volatile and non-toxic
organic compound) were mixed and repacked into plastic cylinders (16 cm high and
9.5 cm in diameter); in order to obtain forty different volumetric combinations of
water and oil (i.e. θfg = θwater + θNAPL), with θNAPL varying from 0.05 to
0.40 by 0.05 cm3/cm3 increments. Data collected were employed to implement a
multiphase mixing model which permitted conversion from a dielectric permittivity
domain into a θf domain and vice versa. The results of this study show that, the
TDR device is NAPL-sensitive, especially for θf values greater than 0.20. Further
works will be built on this initial study, concentrating on improving the dielectric
response-database, in order to: i) enhancing the model efficiency in terms of NAPL capability
detention, and ii) validating the developed TDR interpretation tool with field results. |
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