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7.6.2.1 Introduction Chemical analysis allows determination of the chemical composition of collected samples and, therefore, to identify specific compounds in the chosen environment. Each chemical compound has one or more analytical methods, from the many dif­ferent methods available, that are more suitable for obtaining an accurate determi­nation of concentration. This section of this chapter presents […]

Selective extraction can be considered as an “operational speciation” as it corre­sponds to the quantification of elements bound to specific phases of the soil, rather LEACHING TESTS FOR GRANULAR MATERIALS pH Domain 4-5 pH 5-6 Material Dictated Complexation Low L/S TCLP Swiss TVA DIN 38414 S4 MBLP (Synth) MBLP EPtox NFX-31-210 (California WET EN 12457-3 […]

Leaching can be defined as the process by which soluble constituents are dissolved and filtered through the soil by a percolating fluid, while percolation can be de­scribed as the movement of water downward and radially through subsurface soil layers, continuing downward to groundwater (US EPA, 1997 in ADEME, 1999). This led Tas & Van Leeuwen […]

Contaminants may be held both in pore water and on/in the solids fraction of soil samples. Often it is desirable to know how much contaminant could be released from the sample. Simple separation of the pore water (e. g. by a centrifuge method) will not enable us to know how much contaminant might be released […]

The redox potential, i. e. a measure (in volts) of the affinity of a substance for elec­trons compared with hydrogen, may also be determined in the field using electrical, hand-held equipment, this time employing an inert oxidation-reduction electrode. 7.5.2 Electrical Conductivity Electrical conductivity is typically measured in-situ, being an important, yet sim­ple, indicator of pollution […]

To measure pH in-situ, so-called pH testers (for a rough estimate of the pH value) and pocket (portable) pH meters are used (Fig. 7.9). Periodic calibration of the in­strument is required. The determination of pH is very fast and reliable when a combined glass elec­trode is used. It enables an automatic measurement over long time […]

As physico-chemical and biological reactions occur in the soil and the water, sam­pling periods of short duration are recommended. Some chemical variables should be measured in-situ in a sub-sample (temperature, pH, redox potential, and electrical conductivity) whereas the main water sample is preserved to prevent reduction or loss of target analytes, and transported to the […]

Having entered the soil environment near roads, contaminants will either be retained in the soil or transported through the soil. Depending on soil characteristics and other environmental conditions, different contaminants are transported with the soilwater through the soil at varying rate. Mobile compounds (such as chloride) move rapidly whereas many heavy metals and organic contaminants […]

Groundwater sampling can be performed in existing facilities (wells, piezometers, springs, etc.) or in new ones that need to be built. In this latter case, it is more frequent to install piezometers of a small diameter, just enough to be compatible with the monitoring equipment to be subsequently used. Most groundwater sam­pling installations must be […]

Water samples should be collected from surface water bodies (lakes, rivers, streams, ponds, etc.), taking into account the velocity field in flowing water and any possible stratification in standing water. Once the location and frequency of water sampling are selected there are a set of procedures for sampling water in the natural environ­ment (from surface […]