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  2. Soil contamination - Wikipedia

    en.wikipedia.org/wiki/Soil_contamination

    Contaminated by rocks containing large amounts of toxic elements. Contaminated by Pb due to vehicle exhaust, Cd, and Zn caused by tire wear. Contamination by strengthening air pollutants by incineration of fossil raw materials. The most common chemicals involved are petroleum hydrocarbons, solvents, pesticides, lead, and other heavy metals.

  3. Persistent, bioaccumulative and toxic substances - Wikipedia

    en.wikipedia.org/wiki/Persistent,_bio...

    Another route is the chemical travelling through the soil and ending up in ground water and in human water supply. [15] In the case that the soil is near a moving water system, the chemical could end up in large freshwater systems or the ocean, where fish are at high risk from the toxicological effects of DDT. [ 16 ]

  4. Weathering - Wikipedia

    en.wikipedia.org/wiki/Weathering

    Within the weathering environment, chemical oxidation of a variety of metals occurs. The most commonly observed is the oxidation of Fe 2+ by oxygen and water to form Fe 3+ oxides and hydroxides such as goethite, limonite, and hematite. This gives the affected rocks a reddish-brown coloration on the surface which crumbles easily and weakens the ...

  5. Earth materials - Wikipedia

    en.wikipedia.org/wiki/Earth_materials

    Other earth materials include soil blocks typically stabilized with a cement additive and produced with forms or compression. Rammed Earth consists of walls made from moist, sandy soil, or stabilized soil, which is tamped into form work. Walls are a minimum of 12″ thick. Soils should contain about 30% clay and 70% sand. [4]

  6. Groundwater pollution - Wikipedia

    en.wikipedia.org/wiki/Groundwater_pollution

    Groundwater pollution (also called groundwater contamination) occurs when pollutants are released to the ground and make their way into groundwater.This type of water pollution can also occur naturally due to the presence of a minor and unwanted constituent, contaminant, or impurity in the groundwater, in which case it is more likely referred to as contamination rather than pollution.

  7. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    In the water cycle, the universal solvent water evaporates from land and oceans to form clouds in the atmosphere, and then precipitates back to different parts of the planet. Precipitation can seep into the ground and become part of groundwater systems used by plants and other organisms, or can runoff the surface to form lakes and rivers.

  8. Evaporite - Wikipedia

    en.wikipedia.org/wiki/Evaporite

    A cobble encrusted with halite evaporated from the Dead Sea, Israel (with Israeli ₪1 coin [diameter 18mm] for scale). An evaporite (/ ɪ ˈ v æ p ə ˌ r aɪ t /) is a water-soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. [1]

  9. Contaminants of emerging concern - Wikipedia

    en.wikipedia.org/wiki/Contaminants_of_emerging...

    Water was being disinfected for domestic use through chlorine treatment, which was effective for killing microbial contaminants and bacteria, but in some cases, it reacted with runoff chemicals and organic matter to form trihalomethanes (THMs). Research done in the subsequent years began to suggest the carcinogenic and harmful nature of this ...