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Glossary

Safety level
State in which the risk of harm (to persons) or damage is limited to an acceptable level (ISO 8402). Freedom from those conditions that can cause death, injury, or occupational illness, or damage to or loss of equipment or property, or damage to the environment (882C).

Salinity
A measure of the total concentration of dissolved salts in water. The salinity of ocean water is in the range 33-38 parts per thousand.

Salinization
Change in the salinity status of the soil. It can be caused by improper management of irrigation schemes, mainly in the arid and semiarid regions covering small areas or it may also occur if seawater or fossil saline groundwater intrudes in coastal regions or in closed basins with aquifers of different salt content when there is an excessive use of groundwater. It usually takes place where human activities lead to an increased evapotranspiration in soils on salt containing parent material or with saline groundwater. (source: United Nation, Statistics Division, Environment Glossary)

Sampling
Methods and techniques used to obtain a representative sample of the material under investigation.

Sand
Loose mixture of minerals and rock fragment sediments in which at least 50% have grain sizes that range in size from 0.02 to 2 millimeters in diameter. Quartz, feldspars, micas, and heavy minerals are predominant.

Sand dune
A mound, ridge, or hill of windblown sand.

Saprophagous
Refers to organisms that feed on decaying or decayed plant or animal matter.

Satellite
a)A small, natural celestial body (such as our Moon) revolving around a larger one. b)A man-made object (such as a spacecraft) placed in orbit around the Earth, another planet or the Sun.

Scavenger
An organism that feeds on dead or decomposing animals or macrophytes.

Sciophilous
Thriving in shaded situations, or in habitats of low light intensity.

Scoping
Process by which important environmental issues, project alternatives, and important environmental components are identified by the interested parties. Scoping identifies the potential impacts which are to be addressed in detail by the assessment. Scoping will usually initiate the public consultation/public participation process.

Screening level
Screening level information about a chemical’s toxicity or exposure potential is derived from readily available information using methods that do not require extensive analyses to support preliminary evaluations of chemical safety. Screening level information is useful and necessary for ranking potential problems, directing more detailed investigations, and taking preventative action.

Scrub
Low, woody vegetation composed principally of shrubs.

Seagrass
A flowering plant, complete with leaves, a rhizome (an underground, usually horizontally-oriented stem) and a root system. They are found in marine or estuarine waters. Most seagrass species are located in soft sediments. However, some species are attached directly to rocks with root hair adhesion. Seagrasses tend to develop extensive underwater meadows.

Sealine
see pipeline

Seawater
The mixture of water and various dissolved salts found in the world’s oceans and seas.

Seaweed
Seaweeds are marine algae, saltwater dwelling, simple organisms that fall into the general category of “plants”. Most of them are the red (6000 species), brown (2000 species) or green (1200 species), and most are attached by holdfasts, which just have an anchorage function. These plant-like organisms are found throughout the world’s oceans and seas and none is known to be poisonous. Many are in fact eaten and considered to be a great delicacy.

Second law of thermodynamics
It is not possible for an engine to transfer heat from one body to another at a higher temperature unless work is done on the engine.

Sedimentary basin
A geographical area, whose origin is a depression in the crust of the Earth formed by plate tectonic activity, where much of the rock is sedimentary (as opposed to igneous or metamorphic) and therefore likely to contain hydrocarbons in which sediments accumulate.

Sedimentary rocks
Any rock resulting from the weathered products of pre-existing rocks which have been transported, deposited, compacted, and cemented. Also includes rock that accumulated as chemical precipitates.

Sedimentation
The process of creation, transportation and deposition of sediments like pieces of rock or mineral grains.

Segregated ballast water
A term describing the provision of separate tanks for ballast water only, thus eleminating the need to carry ballast in cargo oil tanks. Tankers must carry about one-third or more of their total capacity in ballast when on an empty part of voyage to improve stability and control the draft of the ships. Usually sea water is used for ballast.

Seismic interpretation
In geophysics, analysis of data to generate predictions and models about the properties and structures of the subsurface. Interpretation of seismic data is the primary concern of geophysicists.

Seismic survey tecniques
A technique for determining the detailed structure of the rocks underlying a particular area by passing acoustic shock waves into the strata and detecting and measuring the reflected signals.

Seismic surveys
Refers to studies done to gather and record patterns of induced shock wave reflections from underground layers of rock which are used to create detailed models of the underlying geological structure.

Seismic wave
Seismic waves are the vibrations from earthquakes that travel through the Earth; they are recorded on instruments called seismographs. (USGS National Earthquake Information Center, 1998)

Selective Catalytic Reduction (SCR)
An emission control technology to reduce nitrogen oxides (NOx) by reduction with ammonia (NH3) in a catalytic reactor.

Selective Non Catalytic Reduction (SNCR)
An emission control technology to reduce nitrogen oxides (NOx) by reduction with ammonia (NH3) without a catalytic reactor.

Selective waste collection
Also known as separate collection: consists of collecting domestic waste which has already been pre-sorted into different categories by householders, so as to enable optimum recovery or specific treatment. Each collection round covers one type of waste.

Semiconductor
Any material that has a limited capacity for conducting an electric current. Generally falls between a metal and an insulator in conductivity. Certain semiconductors, including silicon, gallium arsenide, copper indium diselenide, and cadmium telluride, are uniquely suited to the photovoltaic conversion process.

Serac
A large irregular fragment of glacier ice formed as a glacier moves over a steep icefall.

Service area
The territory in which a utility system or distributor is authorized to provide service to consumers.

Sessile
Describes an immobile organism because of its attachment to a substrate. The term has also been applied to organisms, such as anemones, that move very slowly. Also it refers to plant structures lacking a stalk.

Seston
Minute particulate material moving in water that is composed of both living organisms, such as plankton (see), and non-living matter such as plant debris and suspended soil particles.

Settling tank
A basin or tank in which water or wastewater containing settleable solids is retained to remove by gravity a part of the suspended matter.

Sewage sludges
The accumulated settled solids separated from various types of water either moist or mixed with liquid component as a result of natural or artificial processes. ( source: European Environment Agency)

SI International System of Units
Le Systeme international d’Unités officially came into being in October 1960 and has been officially recognised and adopted by nearly all countries, though the amount of actual usage varies considerably. It is based upon 7 principal units, 1 in each of 7 different categories: Category Name Abbrev. Length metre m Mass kilogram kg Time second s Electric current ampere A Temperature kelvin K Amount of substance mole mol Luminous intensity candela cd Meter [m] The metre is the basic unit of length. It is the distance light travels, in a vacuum, in 1/299792458th of a second. Kilogram [kg] The kilogram is the basic unit of mass. It is the mass of an international prototype in the form of a platinum-iridium cylinder kept at Sevres in France. It is now the only basic unit still defined in terms of a material object, and also the only one with a prefix[kilo] already in place. Second [s] The second is the basic unit of time. It is the length of time taken for 9192631770 periods of vibration of the caesium-133 atom to occur. Ampere [A] The ampere is the basic unit of electric current. It is that current which produces a specified force between two parallel wires which are 1 metre apart in a vacuum.It is named after the French physicist Andre Ampere (1775-1836). Kelvin [K] The kelvin is the basic unit of temperature. It is 1/273.16th of the thermodynamic temperature of the triple point of water. It is named after the Scottish mathematician and physicist William Thomson 1st Lord Kelvin (1824-1907). Mole [mol] The mole is the basic unit of substance. It is the amount of substance that contains as many elementary units as there are atoms in 0.012 kg of carbon-12. Candela [cd] The candela is the basic unit of luminous intensity. It is the intensity of a source of light of a specified frequency, which gives a specified amount of power in a given direction. From the 7 basic units of the SI other units are derived for a variety of purposes. Only a few of are explained here as examples, there are many more. Farad [F] The farad is the SI unit of the capacitance of an electrical system, that is, its capacity to store electricity. It is a rather large unit as defined and is more often used as a microfarad. It is named after the English chemist and physicist Michael Faraday (1791-1867). Hertz [Hz] The hertz is the SI unit of the frequency of a periodic phenomenon. One hertz indicates that 1 cycle of the phenomenon occurs every second. For most work much higher frequencies are needed such as the kilohertz [kHz] and megahertz [MHz]. It is named after the German physicist Heinrich Rudolph Hertz (1857-94). Joule [J] The joule is the SI unit of work or energy. One joule is the amount of work done when an applied force of 1 newton moves through a distance of 1 metre in the direction of the force.It is named after the English physicist James Prescott Joule (1818-89). Newton [N] The newton is the SI unit of force. One newton is the force required to give a mass of 1 kilogram an acceleration of 1 metre per second per second. It is named after the English mathematician and physicist Sir Isaac Newton (1642-1727). Ohm [ ] The ohm is the SI unit of resistance of an electrical conductor. Its symbol, is the capital Greek letter ‘omega’. It is named after the German physicist Georg Simon Ohm (1789-1854). Pascal [Pa] The pascal is the SI unit of pressure. One pascal is the pressure generated by a force of 1 newton acting on an area of 1 square metre. It is a rather small unit as defined and is more often used as a kilopascal [kPa]. It is named after the French mathematician, physicist and philosopher Blaise Pascal (1623-62). Volt [V] The volt is the SI unit of electric potential. One volt is the difference of potential between two points of an electical conductor when a current of 1 ampere flowing between those points dissipates a power of 1 watt. It is named after the Italian physicist Count Alessandro Giuseppe Anastasio Volta (1745-1827). Watt [W] The watt is used to measure power or the rate of doing work. One watt is a power of 1 joule per second. It is named after the Scottish engineer James Watt (1736-1819).

Silicates
Compounds containing silicon, oxygen, and one or more metals; any of a large group of minerals, forming over 90% of the earth’s crust.

Silicon
Atomic symbol, Si, silicon is the 14th element in the periodic table (atomic number 14) with an atomic weight of 28.09. Silicon is a group IV element and is a semiconductor at room temperature with an energy gap of 1.11eV. Silicon is far and away the most widely used semiconductor material.

Silt
Fine particles of sand and rock that can be picked up by the air or by water and deposited as sediments.

Sismic ship
Vessel mapping geological structures in the seabed by firing air guns transmitting sound waves into the bottom of the sea. The echo of the shot is captured by listening devices/hydrophones being towed behind the vessel. A seismic ship provides data which is an intrinsic part of the material determining if and when a test drilling should be initiated.

Skimmer
A mechanical device used to recover (skim) oil from the water’s surface.

Slags
A mixture of substances that are waste products of a furnace. Most slags are composed mainly of silicates.

Slime
A surface growth on, or originating from, a surface which may be jelly-like if form. Such slimes are usually infested with various microorganisms and can act as sites for the bioaccumulation of various chemicals.

Slope instability
Attitude to down-slope movement of soil, rock and organic materials under the influence of gravity. Many factors contribute to the instability of slopes, in addition to the inherent characteristics such as the underlying bedrock and soils, the configuration and geometry of the slope, and ground water conditions, landslides can be triggered by gradual processes such as weathering or by external mechanisms including: erosion, prolonged rainfall, earthquake.

Smog
Smog is a mixture of fog and smoke made up of some primary atmospheric pollutants “trapped” at very low altitude by a “thermal inversion”. The former is meteorological phenomenon whereby, contrary to what occurs normally, air temperature increases with the increase in altitude. Of a particular class is photochemical smog (typical of large urban areas like Los Angeles), generated by the emission of primary pollutants (nitrogen oxides, hydrocarbons). These primary pollutants, in the presence of photochemical reactions triggered by ultra-violet radiations, produce the so-called secondary pollutants (ozone, organic peroxides, aldehydes) which are all chemically highly aggressive.

Soil quality
The capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality, and promote plant and animal health.

Soil vapor extraction
A system of recovery and rehabilitation of soils polluted by volatiles contaminants which creates plains with a depression that withdraws the volatile present in the terrain. The system also includes the treatment of the removed volatiles.

Soil venting
Technology used to remove gasolina vapors from soil without excavation. This method may be applied either passively (with vents that are open to the atmosphere) or actively (using pressure or vacuum pumps).

Soil washing
Soil washing is a water-based chemical-physical process for scrubbing soils ex situ to remove contaminants. The process removes contaminants from soils by dissolving or suspending them in the wash solution (which can contain agents that facilitate the removal of organic substances and metals).

Solar energy collector
A device that gathers and accumulates solar radiation to produce heat.

Solar photovoltaic systems
An installation of PV (photovoltaic) modules and other components designed to produce power from sunlight and meet the power demand for a designated load.

Solar thermal electric systems
Solar energy conversion technologies that convert solar energy to electricity, by heating a working fluid to power a turbine that drives a generator. Examples of these systems include central receiver systems, parabolic dish, and solar trough.

Solubility
The amount of a substance that dissolves in a given volume of solvent at a given temperature.

Solvent
The dissolving medium in a solution.

Sound pressure level
The level, in decibels, of acoustic pressure waves. Commonly, how loud the sound is measured in decibels. Speech is around 70-80 dB at three feet. Normal background noise on average is 50-60dB. 120dB is the threshold of pain. 200dB is 50lbs of TNT detonated 10 feet away.

Sound sources
Any device, machine or living organism which produces noise emissions.

Source rock
A sedimentary rock which is capable of generating hydrocarbons under optimum maturation conditions of temperature, pressure and time.

Special waste
Special waste is a controlled waste from industry or commerce that is regulated under a more stringent regime because of its hazardous nature. Waste oils come under this category. Defined by the Environmental Protection (Special Waste) Regulations 1996 (as amended) and is broadly any waste on the European Hazardous Waste List that has one or more of fourteen hazardous properties.

Species
A population or series of populations of closely related and similar organisms. The individuals within a species are able to interbreed freely with each other, producing healthy, fertile offspring. Members of a species are not able to interbreed successfully with members of other species.

Specific humidity
The mass of water vapor per unit mass of air, including the water vapor (usually expressed as grams of water vapor per kilogram of air).

Spheroid or spheroidal
Any shape that closely resembles or approximates a perfect sphere. In the context of map projections, a spheroid is an ellipsoid of rotation that is flattened at the poles, like the earth.

Spot oil market
An international market in which oil or oil products are traded for immediate delivery at the current price. Most crude moves from producer to refiner under long-term contracts, so only a small fraction of the world’s petroleum is priced and traded on the spot market.

Spread
The difference between two prices, amounts, or numbers such as the bid/ask prices in a commodity trading. In the futures and options markets a spread is the simultaneous purchase and sale of two different contracts in the expectation of a favorable change in their relative prices.

Spring
An issue of water from the earth; a natural fountain; a source of a body or reservoir of water.

Stabilization
Actions taken to further confine or reduce the hazards associated with contaminates sites, areas, buildings or equipment.

Starch
A complex polymer of glucose, used by plants and green algae to store surplus sugar for later use.

Steam cracking
A petrochemical plant unit which produces olefins, particularly ethylene, and in some cases aromatics, by pyrolysis. The trade often calls these plants ethylene crackers, after their primary product. Some units, called light liquids crackers, crack ethane or LPG. Heavy liquids crackers can run on naphtha or gasoil feedstocks.

Steel
An alloy of iron, carbon and often several other elements. The amount of carbon is below 2% by mass – materials with higher levels are termed ‘cast irons’. Steels in which carbon is the main alloying element are termed carbon steels. Those with significant concentrations of other elements are termed alloy steels.

Stock tank oil (originally in place STOOIP)
Amount of oil originally contained in a rock formation, expressed as barrels at stock-tank conditions (i.e., under atmospheric pressure and room temperature). Only a fraction of the STOOIP is ever produced; the oil that remains is beyond the reach of petroleum engineering in today’s economic climate.

Storage
Typically onland tankage facilities for short- or long-term storage of crude or products; the term sometimes is used interchangeably with the concept of oil stocks.

Straight run
A material produced by distillation of crude oil without appreciable cracking or alteration of the molecules in the product.

Strategic Petroleum Reserves (SPR)
Petroleum stocks maintained by national governments or oil companies for use during periods of major supply interruption.

Stratosfera
The layer of atmosphere that ranges from about 20 to 50 km in altitude above the Earth’s surface. In the stratosphere, the temperature rises with increasing height, which is the opposite of the situation in the lower atmosphere. Ozone (see) occurs in minute quantities throughout the full depth of the atmosphere, but its concentration peaks within the stratosphere at an altitude of about 35 kilometers. This is referred to as the ozone layer (see).

Stream
A body of water that is confined to a channel and moves downhill under the force of gravity.

Streamer
A surface marine cable, consisting of an assembly of electrical wires that connects hydrophones and relays seismic data to the recording seismic vessel. Multistreamer vessels tow more than one streamer cable to increase the amount of data acquired in one pass.

Stripping
A separation process that consists in injecting water steam into the distillation residue in order to recover the lightest molecules.

Styrene
A colourless liquid with a strong aromatic aroma. Insoluble in water, soluble in alcohol and ether; polymerizes rapidly; can become explosive. Used to make polymers and copolymers, polystyrene plastics, and rubber…

Subsidence
Alteration of land’s equilibrium consisting in a slow vertical lowering of the topographical surface. This phenomenon can occur, given certain conditions, following the withdrawal of fluids from the sub-oil (water, gas, liquid hydrocarbons).

Sulphur
Sulphur is found in crude oil in the form of both metal sulphur and organic sulphur compounds such as H2S. The lower the sulphur content, the higher the crude quality, as it is easier to refine such oils. Pure sulphur is also produced as a secondary product of the desulphurisation processes in the refinery and sold for subsequent transformation.

Sulphur oxides
Emissions of sulphur oxides, mainly made up of sulphur dioxide (SO2), are primarily caused by the combustion of solid and liquid fuels and are correlated to the sulphur content of the fuel. Sulphur oxides are typical urban and industrial area pollutants, where the high density and extent of built-up areas create a favourable environment for their accumulation, especially under unfavourable meteorological conditions. The most serious cases occur during the winter, when household heating is added to the other sources of emission.

Sulphuric acid
Sulfuric acid (H2SO4), also called oil of vitriol, or hydrogen sulfate, is a dense, colourless, oily, corrosive liquid; one of the most important of all chemicals, prepared industrially by the reaction of water with sulfur trioxide, which in turn is made by chemical combination of sulfur dioxide and oxygen. In various concentrations the acid is used in the manufacture of fertilizers, pigments, dyes, drugs, explosives, detergents, and inorganic salts and acids, as well as in petroleum refining and metallurgical processes.

Surfactant
A natural or synthetic chemical that promotes the wetting, solubilization, and emulsification of various types of organic chemicals.

Sustainable development
As defined by the 1978 Bruntland report (the United Nations World Commission on Environment and Development, The Brundtland Commission, 1987), is said sustainable development “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” Sustainable development is a policy and a strategy intended to ensure the continuity of economic and social development over time, with respect for the environment, and without compromising the natural resources required for human activity.

Swamp
Wetland area of mineral soil normally flooded in the growing season and dominated in most cases by emergent macrophytes (broad-leaved plants), shrubs, and/or trees.

Swing producer
The most dominant member of a cartel, and the one which is expected to support the weaker members when they have difficulty in living within the cartel’s terms. The swing producer either boosts supply by adding extra production at short notice, or reduces it by withholding production. Within OPEC, the oil-producers’ cartel, Saudi Arabia plays the role of swing producer.

Symbiosis
Symbiosis (“living together” in Greek) is a situation in which two dissimilar organisms are living in close contact. There are many types of symbiosis, including mutualism (in which both organisms benefit), commensalism (in which one organism benefits and the other is not affected), or parasitism (in which one organism benefits at the other organism’s expense).

Synthesis
A chemical reaction of elements to form a compound.

Synthetic compound
Compounds produced by total synthesis from unrelated and base reactants.

Synthetic lubricants
Lube oils possessing a base oil that has been manufactured from chemical constituents or by the polymerization of hydrocarbons (olefins) rather than by conventional refining of petroleum. The three most common types of synthetic base oils are: Polyalpolefins, Organic esters, Polyglycols. Synthetic lubricants have several advantages over conventional mineral oils as: excellent low temperature fluidity, low pour point, high natural viscosity index, excellent oxidation stability, high flash, fire, and auto-ignition points, low volatility.

Synthetic resin
Complex chemical resins produced through reactions of simple molecules.

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