What are VOCs in groundwater?
Volatile organic compounds (VOCs) are chemicals that both vaporize into air and dissolve in water. Once released into groundwater, many VOCs are persistent and can migrate to drinking-water supply wells.
How do VOCs affect water?
VOCs evaporate, or vaporize, easily into air at normal air temperatures and when in contact with water may dissolve in and be transported by water. In addition, dissolved organic chemicals in water may vaporize out of water into the air.
Which of the following is a VOC that contaminates groundwater?
Contaminants include xylene, methyl ethyl ketone, methylene chloride, acetone, phthalates, anthracene, toluene, fluoranthene, alkyl benzene, vinyl chloride, dichloroethylene, and aliphatic acids.
What are 5 common sources of VOCs?
Sources of VOCs
- Paint, varnishes, caulks, adhesives.
- Carpet, vinyl flooring.
- Composite wood products.
- Upholstery and foam.
What does VOC mean in water?
Volatile organic compounds
VOCs are common ground-water contaminants. Volatile organic compounds (VOCs) are emitted as gases from certain solids or liquids. VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects.
How are VOCs removed from water?
The activated carbon filter cartridge will absorb the carbon-based VOCs as they pass through the filter, rendering the water VOC-free. The most effective way of removing VOCs from drinking water is through carbon filtration.
How are VOCs treated in water?
Reverse osmosis drinking water treatment systems cannot remove VOCs, which will pass through the membrane, unless they have a carbon filter fitted before or after the reverse osmosis membrane. The most effective way of removing VOCs from drinking water is through carbon filtration.
What are VOCs used for?
What are volatile organic compounds (VOCs)? Volatile organic compounds are compounds that have a high vapor pressure and low water solubility. Many VOCs are human-made chemicals that are used and produced in the manufacture of paints, pharmaceuticals, and refrigerants.
How do VOCs get into groundwater?
VOCs get into the environment through industrial dumping, leaks, spills or from the use and improper disposal of household products that contain these chemicals. VOCs in groundwater can cause problems for people who depend on well water for domestic and irrigation purposes.
How do you remove VOCs from well water?
The best way to remove VOCs from drinking water is to filter it with a good quality carbon filter, such as the Berkey water filter. The activated carbon filter cartridge will absorb the carbon-based VOCs as they pass through the filter, rendering the water VOC-free.
What is a VOC in construction?
Refresher Training or a ‘Verification of Competency’ (V.O.C.) is a method of assessment that can be used to demonstrate a worker’s ability to operate equipment and/or undertake the responsibilities of certain duties.
What causes VOC?
Other sources of VOCs include the burning of fuels such as gas, wood and kerosene and tobacco products. VOCs can also come from personal care products such as perfume and hair spray, cleaning agents, dry cleaning fluid, paints, lacquers, varnishes, hobby supplies and from copying and printing machines.
What kind of VOCs can be found in groundwater?
Gasoline compounds and additives are another class of VOCs that is sometimes detected in groundwater. Leaking underground gasoline storage tanks are a common, but unseen, source of gasoline VOCs to groundwater. Methyl tert-butyl ether (MtBE) in groundwater illustrates the law of unintended consequences.
How are VOCs transported from water to air?
Although VOCs tend to escape from surface water through volatilization (evaporation) into the air, once dissolved in groundwater they are more persistent. They can be transported through the unsaturated zone in recharge, in soil vapor, or as a non-aqueous-phase liquid.
How does VOC move in the saturated zone?
Once in the saturated zone, some highly soluble VOCs, such as the gasoline additive MTBE, move with the groundwater, whereas other VOCs, like carbon tetrachloride, are slowed when they adhere to organic carbon in the aquifer solids.
What do you need to know about VOC analysis?
Groundwater samples for VOC analysis must be collected in 40 ml glass vials with Teflon® septa. The vial may be either preserved with concentrated hydrochloric acid or they may be unpreserved. Preserved samples have two-week holding time, whereasa unpreserved samples have only a seven-day holding time.