Modeling in situ ozonation for the remediation of nonvolatile PAH-contaminated unsaturated soils

2002 ◽  
Vol 55 (3-4) ◽  
pp. 261-285 ◽  
Author(s):  
Jeongkon Kim ◽  
Heechul Choi
Keyword(s):  
Unsaturated Soils

scholarly journals Ferum concretions in the soils of the Lviv region

2017 ◽  
pp. 256-266 ◽  
Author(s):  
Zinoviy Pankiv ◽  
Olena Iliasevych ◽  
Stepan Malyk
Keyword(s):  
Unsaturated Soils ◽  
Podzolic Soil ◽  
Soil Material ◽  
Profile Distribution ◽  
High Level ◽  
Soil Forming Processes ◽  
Reducing Potential ◽  
Main Factor ◽  
Brown Color

It is established that ferum concretions can be observed in 60 % area of Lviv’s oblast’s and represented by brown spots, pseudophybras, ortsteins, ortzanders, nodules, layers of marsh ore. In acidic unsaturated soils of Male Polissya, Nadsanya, Precarpathians ferum concretions is the basis for diagnosing soil-forming processes and their genesis. The main factor of ferum concretions formation is the dynamics of oxidation-reducing potential. Fe-Mn pedofetures (ortsteins) dominated in the sodpodzolic gleyed soils of Malogo Pollisya, Nadsanya and in the sod-podzolic pseudogleyed soils of the Precarpathians. Their profile distribution and morphological features. Were established nodules (solid concretions of a dark brown color with a gray tint, irregular shape and with diffuse outlines) were diagnosed within the EI horizon of the brown-podzolic soil of the Precarpathians. Found features of nodules testify about the genesis of in situ. Sod glesish soils of Male Polissya, Precarpathians, valleys Pasmovogo Pobyzzya are characterized by ferum concretions of a dense consistency, a dark brown color with diffuse outlines, which are formed in horizons with long saturation of water due to cementation with soil material of oxides Fe, Al, Mn, Si. Ferum concretions are characterized by maximum accumulation of iron compound (Кх=7,21). Ortzanders and pseudophybras - glandular hydrogenated cemented neoplasms formed are within the profi les of sod pinewood soils of Male Polissya, Nadsanya which were formed on the water-glacial deposits and sod soils in the Davudiv range, formed on Neogene sands on the conditions of high level ironization of ground water and pulsating regime. Little attention is paid to the study of ferum concretions in the soils, which is a significant disadvantage in the study of the genesis of hydromorphic soils. In order to establish the genetic nature, of ferum concretions it is advisable to use modern methods of scanning electronic microscopy, mineralogical and micromorphological studies. Key words: ferum concretions, Fe-Mn pedofetures, ortsteins, nodules, soils.

Time-resolved in-situ pH measurement in differently treated, saturated and unsaturated soils

2015 ◽  
Vol 178 (3) ◽  
pp. 425-432 ◽  
Author(s):  
Sören Thiele-Bruhn ◽  
Stefan Wessel-Bothe ◽  
Marc-Oliver Aust
Keyword(s):  
Unsaturated Soils ◽  
Ph Measurement ◽  
Time Resolved

scholarly journals Novel rapid measurement system of undisturbed soils water characteristics curve utilizing the continuous pressurization method

2019 ◽  
Vol 92 ◽  
pp. 07008 ◽  
Author(s):  
Adel Alowaisy ◽  
Noriyuki Yasufuku ◽  
Ryohei Ishikura ◽  
Masanori Hatakeyama ◽  
Shuu Kyono
Keyword(s):  
Soil Water ◽  
Unsaturated Soils ◽  
Natural Soil ◽  
Undisturbed Soil ◽  
Water Characteristics ◽  
Undisturbed Samples ◽  
In Situ Conditions ◽  
Undisturbed Soils ◽  
Short Time

Through this paper, a sampling methodology and a novel full automatic system adopting the continuous pressurization method which is capable of determining the Soil Water Characteristics Curve (SWCC) for both remoulded and undisturbed samples in a very short time were developed. The proposed system was validated by comparing the SWCCs of standard testing soils obtained using the developed system to the SWCCs obtained using a conventional method. Remoulded and undisturbed natural soil samples were tested, where the degree of disturbance influence on the obtained SWCC was discussed. In addition, the undisturbed samples containing moulds material influence on the obtained SWCC was investigated. It was found that remoulded samples do not properly represent the in-situ conditions with significant error that should be carefully considered when conducting analysis and proposing countermeasures against unsaturated soils related Geo-disasters. In addition, the material which the containing mould is made from has minor influence on the obtained SWCC which can be neglected. Finally, it can be concluded that the developed undisturbed soil water characteristics curve obtaining system is direct, rapid, reliable and simple. In addition, the proposed undisturbed sampling and testing methodology can be used to accurately evaluate the spatial variations of the SWCC regardless the heterogeneity of the soil profile.

Water flow in unsaturated soils subjected to multiple infiltration events

2020 ◽  
Vol 57 (3) ◽  
pp. 366-376
Author(s):  
Xiaokun Hou ◽  
Sai K. Vanapalli ◽  
Tonglu Li
Keyword(s):  
Water Content ◽  
Water Flow ◽  
Unsaturated Zone ◽  
Unsaturated Soils ◽  
Water Infiltration ◽  
Wetting Front ◽  
Influx Rate ◽  
The Relationship ◽  
Stable Zone

In this paper, water flow in a 4 m height column with an unsaturated soil that is subjected to multiple infiltration events for a 62 day period is investigated. One-dimensional (1D) numerical analysis is also undertaken to analyze the flow, extending the seepage theory for unsaturated soils. Results highlight the formation of two wetting fronts; namely, wetting front I and wetting front II that are induced by the first and subsequent infiltration events, respectively. There is a stable zone where the water content is approximately constant; it forms between the two fronts. A conceptual model of the suction profile is proposed for interpreting in situ water flow by dividing the unsaturated zone into four distinct zones; namely, active, steady, transition, and capillary fringe zones. This division is helpful for providing a rational explanation of water flow in different zones. Novel contributions from this study include a relationship between the hydraulic properties in the steady zone and the flow velocity, which is determined by an average influx rate. In addition, the rate of groundwater recharge can also be estimated using the average influx rate. Results of the present study are useful to understand and interpret the relationship between water infiltration and suction or water content profile in the unsaturated zone as well as variation of groundwater table level.

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