Sampling soil undisturbed

Test pits permit visual examination of the soil in place. Such pits also allow manual sampling of undisturbed soil samples. These samples can be taken from the side walls of the pit. 

Hvorslev (1949) classified soil samples as nonrepresentative, representative, or undisturbed. This classification is made by comparing the state of the sampled soil to that as exists in situ. A nonrepresentative sample is one in which soils from different strata have been mixed, or some of the soil constituents of the sampled soil are missing. Samples that contain scrapings from the well of the borehole or samples with some of the fine particles washed out during sampling fall in this category. A representative soil sample is one in which there is no change in soil constituents but whose structure, water content, or void ratio has been altered. An xmdisturbed sample, ideally, is one that represents the in situ condition. 

G. Matschonat and R. Vogt, Equilibrium solution composition and exchange properties of disturbed and undisturbed soil samples from an acid fore.st soil. Plant Soil I83 l (1996). 

In Table 7, a comparison of actual measurements, and also two well-known pedo-transfer functions, can be found by depth. It is important to note that there is a large difference in water content between the disturbed soil core samples and the undisturbed samples. Additionally, the two pedo-transfer functions also exhibit a large difference in predicted water content. Therefore, when doing calculations or trying... 

In a recent study, Carlsen and colleagues [22] investigated the occurrence of LAS in a series of soil samples from seven different locations with different histories. Ten centimetre subsamples of the 50 cm cores were extracted using a microwave technique and the analyses were carried out using HPLC-FL. With the exception of two sites the LAS concentrations were found to range from [Pg.820]

Evaluations of various soil and sediment samplers have been reported [56, 57]. The sediment shovel proved highly practical, but was limited because small particles tend to be lost when the shovel is lifted [56]. A cryogenic sediment sampler was less convenient to use, but allowed the collection of almost undisturbed samples. Houba described a different device for the automatic subsampling of soil, sediment and plant material for proficiency testing [57]. In another study, Thoms showed that freeze-sampling collects representative sediment samples, whereas grab-sampling introduces a bias into the textural composition of the 120 mesh fraction, due to washout and elutriation of the finer fractions [58]. 

In those climatic regions where humus is developed, it is normally found in undisturbed forested areas above the normal mineral soil. Decomposed black coloured organic material (humus) should be sampled. 

Collect undisturbed soil samples at the bottom and sidewalls of the pit. 

Once the operator brings the full bucket to the ground surface, collect a sample from an undisturbed portion of soil in the bucket. 

During Phase I, a geological survey was carried out from November 1997 to April 1998 at the brownfield site (ILVA and Etemit areas). During the survey, shallow and deep cores were collected reworked and undisturbed soil was sampled and groundwater samples were collected. In addition, a detailed geophysical survey was undertaken to establish a terrain lithostratigraphy, to determine the mechanical properties of the terrains, and to map the water table. 

The usual method for obtaining samples at significant depths below the surface is to push or drive a pipe or tube into undisturbed soil at the bottom of a drill hole. Of course, this process disturbs the soil, particularly when the pipe is heavy walled. Many different kinds and sizes of samplers are used, and the most common is shown in Figure 1.1. This sampler is commonly called a split spoon. When used with the dimensions shown, and hammered into the soil by a free falling, 140 pound weight, dropping 30 inches, this is the Standard Penetration Test (see ASTM Standard D.1586,... 

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