Hydraulic containment

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The word "hydraulic" originates from the Greek word ὑδραυλικός (hydraulikos) which in turn stems from ὕδωρ (hydor, Greek for water) and αὐλός (aulos, meaning tube), and "containment" refers to the action of keeping something harmful under control or within limits. Thus, hydraulic containment is the attempt of confining the movement of any harmful fluid within a limit. In the pollution management sense, hydraulic containment is a technique used to control the movement of contaminated groundwater, preventing the continued expansion of the contaminated zone. It is the first step of pump and treat [1] technology for environmental remediation.

Greek language language spoken in Greece, Cyprus and Southern Albania

Greek is an independent branch of the Indo-European family of languages, native to Greece, Cyprus and other parts of the Eastern Mediterranean and the Black Sea. It has the longest documented history of any living Indo-European language, spanning more than 3000 years of written records. Its writing system has been the Greek alphabet for the major part of its history; other systems, such as Linear B and the Cypriot syllabary, were used previously. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems.

Water chemical compound

Water is a transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms. It is vital for all known forms of life, even though it provides no calories or organic nutrients. Its chemical formula is H2O, meaning that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. Water is the name of the liquid state of H2O at standard ambient temperature and pressure. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds are formed from suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor. Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.

In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, or external force. Fluids are a phase of matter and include liquids, gases and plasmas. They are substances with zero shear modulus, or, in simpler terms, substances which cannot resist any shear force applied to them.

Contents

Description

The hydraulic containment process is accomplished by three [2] major configurations:

The set-up of the underground water pumping wells and the pumping system are subjected on the characteristics of the site and type of containment and requires an effective design and operational effort to meet the goal of cleaning. After the 'containment' is done, according to the contamination type and extent, contaminated water can be treated by different conventional or modified physical, chemical or biological methods usually applied in waste water treatment facilities. [1]

Wastewater treatment Converting wastewater into an effluent for return to the water cycle

Wastewater treatment is a process used to remove contaminants from wastewater or sewage and convert it into an effluent that can be returned to the water cycle with minimum impact on the environment, or directly reused. The latter is called water reclamation because treated wastewater can then be used for other purposes. The treatment process takes place in a wastewater treatment plant (WWTP), often referred to as a Water Resource Recovery Facility (WRRF) or a sewage treatment plant. Pollutants in municipal wastewater are removed or broken down.

Application

As part of pollution management work, this technique can be used to groundwater contaminated with different types dissolved materials, oils, explosives and dissolved metals.

Benefits

There are a number of different waste treatment technologies for the disposal, recycling, storage, or energy recovery from different waste types. Each type has its own associated methods of waste Management

Limitations

The technique has some limitations. The pumping may put threat to lowering of groundwater level. Again, the operating costs can be expensive because of the labor-intensive requirements of the method.

Groundwater water located beneath the ground surface

Groundwater is the water present beneath Earth's surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from and eventually flows to the surface naturally; natural discharge often occurs at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology.

Biological

Trees possess the features to act like living pumps as it pulls water out of the ground for its physiological process. This feature attracted environmentalists and led them to think about the possibility of biological hydraulic containment.

Plants such as willow, sunflower, okra, most of the poplars (such as aspen and cottonwood), pull a large amount of capillary water out of the ground, which can be a useful property of some pollution management efforts and environmental engineering. Plants that draw water upwards through the soil into the roots and out through the plant decreases the movement of soluble contaminants downwards, deeper into the site and into the groundwater. Poplars, for example, take up large quantities of water, transpiring between 200 and 1100 liters daily. With the functional water table depression created, pollutants are drawn and then taken up for an additional treatment process. [5]

Related Research Articles

Water pollution Contamination of water bodies

Water pollution is the contamination of water bodies, usually as a result of human activities. Water bodies include for example lakes, rivers, oceans, aquifers and groundwater. Water pollution results when contaminants are introduced into the natural environment. For example, releasing inadequately treated wastewater into natural water bodies can lead to degradation of aquatic ecosystems. In turn, this can lead to public health problems for people living downstream. They may use the same polluted river water for drinking or bathing or irrigation. Water pollution is the leading worldwide cause of death and disease, e.g. due to water-borne diseases.

Environmental remediation deals with the removal of pollution or contaminants from environmental media such as soil, groundwater, sediment, or surface water. This would mean that once requested by the government or a land remediation authority, immediate action should be taken as this can impact negatively on human health and the environment.

Phytoremediation /ˌfaɪtəʊrɪˌmiːdɪˈeɪʃən/ refers to the technologies that use living plants to clean up soil, air, and water contaminated with hazardous contaminants. It is defined as "the use of green plants and the associated microorganisms, along with proper soil amendments and agronomic techniques to either contain, remove or render toxic environmental contaminants harmless".

Agricultural wastewater treatment Farm management agenda for controlling pollution from surface runoff in agriculture

Agricultural wastewater treatment is a farm management agenda for controlling pollution from surface runoff that may be contaminated by chemicals in fertiliser, pesticides, animal slurry, crop residues or irrigation water.

Soil contamination pollution of land by human-made chemicals or other alteration

Soil contamination or soil pollution as part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals, or improper disposal of waste. The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons, solvents, pesticides, lead, and other heavy metals. Contamination is correlated with the degree of industrialization and intensity of chemical substance. The concern over soil contamination stems primarily from health risks, from direct contact with the contaminated soil, vapors from the contaminants, and from secondary contamination of water supplies within and underlying the soil. Mapping of contaminated soil sites and the resulting cleanups are time consuming and expensive tasks, requiring extensive amounts of geology, hydrology, chemistry, computer modeling skills, and GIS in Environmental Contamination, as well as an appreciation of the history of industrial chemistry.

A waste pond or chemical pond is a small impounded water body used for the disposal of water pollutants, and sometimes utilized as a method of recycling or decomposing toxic substances. Such waste ponds may be used for regular disposal of pollutant materials or may be used as upset receivers for special pollution events. Often, chemical ponds themselves are addressed for cleanup action after their useful life is over or when a risk of groundwater contamination arises. Peak usage of waste ponds in the United States occurred in the period 1955 to 1985, after which the environmental risks of pond technology were sufficiently understood, such that alternative technologies for waste disposal gradually began to displace many of the waste ponds. Waste ponds often have pond liners, such as concrete or robust synthetic polymeric materials, to prevent infiltration of chemicals to soil or groundwater.

Soil vapor extraction (SVE) is a physical treatment process for in situ remediation of volatile contaminants in vadose zone (unsaturated) soils. SVE is based on mass transfer of contaminant from the solid (sorbed) and liquid phases into the gas phase, with subsequent collection of the gas phase contamination at extraction wells. Extracted contaminant mass in the gas phase is treated in aboveground systems. In essence, SVE is the vadose zone equivalent of the pump-and-treat technology for groundwater remediation. SVE is particularly amenable to contaminants with higher Henry’s Law constants, including various chlorinated solvents and hydrocarbons. SVE is a well-demonstrated, mature remediation technology and has been identified by the U.S. Environmental Protection Agency (EPA) as presumptive remedy.

Green nanotechnology refers to the use of nanotechnology to enhance the environmental sustainability of processes producing negative externalities. It also refers to the use of the products of nanotechnology to enhance sustainability. It includes making green nano-products and using nano-products in support of sustainability.

The CSIR-National Environmental Engineering Research Institute (CSIR-NEERI) is a research institute created and funded by Government of India. It was established in Nagpur in 1958 with focus on water supply, sewage disposal, communicable diseases and to some extent on industrial pollution and occupational diseases found common in post-independent India. NEERI is a pioneer laboratory in the field of environmental science and engineering and part of Council of Scientific and Industrial Research (CSIR). NEERI has five zonal laboratories at Chennai, Delhi, Hyderabad, Kolkata and Mumbai. NEERI falls under the Ministry of Science and Technology (India) of central government. The NEERI is an important partner organisation in India’s POPs national implementation plan (NIP).

Rhizofiltration

Rhizofiltration is a form of phytoremediation that involves filtering contaminated groundwater, surface water and wastewater through a mass of roots to remove toxic substances or excess nutrients.

Groundwater remediation is the process that is used to treat polluted groundwater by removing the pollutants or converting them into harmless products. Groundwater is water present below the ground surface that saturates the pore space in the subsurface. Globally, between 25 per cent and 40 per cent of the world's drinking water is drawn from boreholes and dug wells. Groundwater is also used by farmers to irrigate crops and by industries to produce everyday goods. Most groundwater is clean, but groundwater can become polluted, or contaminated as a result of human activities or as a result of natural conditions.

NC State University is a Superfund site in Raleigh, North Carolina located to the north of Carter–Finley Stadium. It is a 1.5-acre (6,100 m2) site that was used from 1969 until 1980 to dispose of hazardous waste from laboratories and research facilities. The North Carolina State University Department of Marine, Earth, and Atmospheric Sciences began monitoring the site in 1981, drilling wells and sampling the groundwater. Groundwater remediation is currently being conducted at the site via pump and treat methods to remove chemicals of concern, including chloroform, bromoform, 1,1,1-trichloroethane, and methylene chloride.

In situ chemical oxidation (ISCO), a form of advanced oxidation processes and advanced oxidation technology, is an environmental remediation technique used for soil and/or groundwater remediation to reduce the concentrations of targeted environmental contaminants to acceptable levels. ISCO is accomplished by injecting or otherwise introducing strong chemical oxidizers directly into the contaminated medium to destroy chemical contaminants in place. It can be used to remediate a variety of organic compounds, including some that are resistant to natural degradation.

A permeable reactive barrier (PRB), also referred to as a permeable reactive treatment zone (PRTZ), is a developing technology that has been recognized as being a cost-effective technology for in situ groundwater remediation. PRBs are barriers which allow some—but not all—materials to pass through. One definition for PRBs is an in situ treatment zone that passively captures a plume of contaminants and removes or breaks down the contaminants, releasing uncontaminated water. The primary removal methods include: (1) sorption and precipitation, (2) chemical reaction, and (3) reactions involving biological mechanisms.

Zerovalent iron

Zerovalent iron and other zerovalent metals have a variety of applications ranging from filters to electrodes to trenches. One of the emerging uses for ZVI is iron wall remediation. This technology uses ZVIs to form a permeable reactive barrier (PRB) which filters out contaminants in groundwater, leaving only decontaminated groundwater and dissolved iron on the other side of the PRB.

The 70-acre Burlington Northern is a former railroad tie treatment plant by Burlington Northern Railroad in Northern Minnesota. The unlined creosote and fuel oil lagoons, which had been used to treat the ties contaminated groundwater. In 1985 the site was listed as a United States Environmental Protection Agency (EPA) Superfund. Contaminated soils were excavated and capped and a groundwater gradient pump out well is in place.

Air sparging, also known as in situ air stripping and in situ volatilization is an in situ remediation technique, used for the treatment of saturated soils and groundwater contaminated by volatile organic compounds (VOCs) like petroleum hydrocarbons which is a widespread problem for the ground water and soil health. The vapor extraction has manifested itself into becoming very successful and practical when it comes to disposing of VOCs. It was used as a new development when it came to saturated zone remediation when using air sparging. Being that the act of it was to inject a hydrocarbon-free gaseous medium into the ground where contamination was found. When it comes to situ air sparging it became an intricate phase process that was proven to be successful in Europe since the 1980s. Currently, there have been further development into bettering the engineering design and process of air sparging.

Nanoremediation is the use of nanoparticles for environmental remediation. It is being explored to treat ground water, wastewater, soil, sediment, or other contaminated environmental materials. Nanoremediation is an emerging industry; by 2009, nanoremediation technologies had been documented in at least 44 cleanup sites around the world, predominantly in the United States. In Europe, nanoremediation is being investigated by the EC funded NanoRem Project. A report produced by the NanoRem consortium has identified around 70 nanoremediation projects worldwide at pilot or full scale. During nanoremediation, a nanoparticle agent must be brought into contact with the target contaminant under conditions that allow a detoxifying or immobilizing reaction. This process typically involves a pump-and-treat process or in situ application.

Groundwater pollution pollutants in groundwater

Groundwater pollution occurs when pollutants are released to the ground and make their way down 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.

Water in Arkansas is an important issue encompassing the conservation, protection, management, distribution and use of the water resource in the state. Arkansas contains a mixture of groundwater and surface water, with a variety of state and federal agencies responsible for the regulation of the water resource. In accordance with agency rules, state, and federal law, the state's water treatment facilities utilize engineering, chemistry, science and technology to treat raw water from the environment to potable water standards and distribute it through water mains to homes, farms, business and industrial customers. Following use, wastewater is collected in collection and conveyance systems, decentralized sewer systems or septic tanks and treated in accordance with regulations at publicly owned treatment works (POTWs) before being discharged to the environment.

References

  1. 1 2 Mackay, Douglas M.; Cherry, John A. (2002-05-01). "Groundwater contamination: pump-and-treat remediation". Environmental Science & Technology. 23 (6): 630–636. doi:10.1021/es00064a001.
  2. "Passive and hydraulic Containment". www.eugris.info. Retrieved 2016-03-24.
  3. Meggyes, T. and Simon, F.G., 2000. Removal of organic and inorganic pollutants from groundwater using permeable reactive barriers. Land Contamination & Reclamation, 8(3), p.3.
  4. "4-47 Ground Water Pumping". frtr.gov. Retrieved 2016-03-24.
  5. Evans, Gareth M.; Furlong, Judith C. (2010-01-01). Phytotechnology and Photosynthesis. John Wiley & Sons, Ltd. pp. 145–174. doi:10.1002/9780470975152.ch7/summary. ISBN   9780470975152.