Groundwater anthropogenic

Regarding POCs, eight compounds (see Table 1) were selected as indicators from the qualitative analysis of leachate due to their frequent detection, to their abundance, and to their absence in groundwater wells monitored upstream the landfill. The selected compounds include plasticizers or their degradation products, insect repellent and natural compounds resulting from anthropogenic pollution. 

Heavy metals are introduced into the soil mainly by the application of fertilizers, sewage sludge, liming materials, and other industrial and urban waste materials. In recent years, increased anthropogenic inputs of heavy metals in terrestrial environments have caused considerable concern relative to their impact on groundwater... 

The trace elements are introduced into seawater by river runoff, atmospheric transport, hydrothermal venting, groundwater seeps, diffusion from the sediments, and transport from outer space, usually as micro meteorites. The magnitudes of the first three of these fluxes, which are considered to be the major ones, are given in Table 11.1. Anthropogenic activities have significantly increased some of these fluxes, as discussed later. 

Clara M, Strenn B, Kreuzinger N (2004) Carbamazepine as a possible anthropogenic marker in the aquatic environment investigations on the behaviour of carbamazepine in wastewater treatment and during groundwater infiltration. Water Res 38 947-954... 

Regnery J, Puttmann W, Merz, C, Berthold G (2011) Occurrence and distribution of organo-phosphorus flame retardants and plasticizers in anthropogenically affected groundwater. J Environ Monit 13 347-354... 

The zone between land surface and the water table, which forms the upper boundary of the groundwater region, is known as the vadose zone. This zone is mostly unsaturated— or more precisely, partially saturated— but it may contain a saturated fraction in the vicinity of the water table due to flucmations in water levels or capillary rise above the water table. The near-surface layer of this zone—the soil—is generally partially saturated, although it can exhibit periods of full saturation. Soil acts as a buffer that controls the flow of water among atmosphere, land, and sea and functions as a sink for anthropogenic contaminants. 

Chromium is a common anthropogenic contaminant in surface waters, therefore Cr isotope fractionations are of potential interest in tracking Cr + pollution in groundwaters. Ellis et al. (2002, 2004)) and Izbicki et al. (2008) analyzed ground-water samples from contaminated sites and observed an increase in Cr/ Cr ratios up to 6%c during the reduction of chromate. Equilibrium fractionations between Cr(VI) and Cr (III) have been estimated by Schauble et al. (2002), who predicted Cr isotope fractionations >l%c between Cr species with different oxidation states. 

Again, the absence of monitoring data does not necessarily indicate a lack of cresols in the environment. Cresols are widely occurring natural and anthropogenic products. However, biodegradation is probably the dominant mechanism responsible for the rapid removal of cresols from surface waters (see Section 5.3.2.2). Nevertheless, cresols may persist in extremely oligotrophic waters, in waters with limited microbial communities, and/or under anaerobic conditions such as in some sediments and groundwater aquifers. 

Tables 5-2a through 5-2e summarize the literature data on cresols found in groundwater and their respective anthropogenic sources. STORET (1989) did not contain records for o-cresol in groundwater. 

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