Breagh Development - RWE.com

Glossary
Breagh Environmental Statement
Non Technical Summary
Acute Of Short duration
Annulus The ring shaped cavity between 2 concentric tubes, e.g. inner and outer
strings of casing, or between casing, or drill pipe, and the well borehole.
Appraisal well A well drilled to confirm the size or quality of a hydrocarbon discovery.
Before development, a discovery is likely to require at least 2 or 3 of such
wells.
Barite A very heavy substance used as a main component of drilling mud to
increase its density and counter balance down-hole pressures.
Bathymetry The measurement of ocean depth and the study of floor topography.
Benthic Relating to organisms that are attached to, or resting on, the bottom
sediments.
Bioaccumulate The increasing concentration of compounds within fauna such as limpets,
oysters and other shellfish.
Biocide A chemical toxic or lethal to living organisms.
Biogenic Produced by the action of living organisms
Biomagnify Increase in toxicity within a species
Block Sub-division of sea for the purpose of licensing to a company or group of
companies for exploration and production rights. A UK block is
approximately 200 – 250km 2 .
Casing Steel lining used to prevent caving of the sides of a well, to exclude
unwanted fluids and to provide a means to control well pressures and oil
and gas production.
Cetacean Aquatic animals comprising porpoises, dolphins and whales.
Choke An aperture restricting flow in a well or flowline.
Christmas Tree An assembly of isolation valves, chokes and gauges installed at the top of
a well to control the flow of oil and gas once a well has been completed.
Condensate Light hydrocarbon fractions produced with natural gas which condense
into liquid at normal temperatures and pressures associated with surface
production equipment.
Cuttings pile Pile of primarily rock chips deposited on the seabed as a result of drilling
activities.
Demersal Living at or near the bottom of the sea.
Dinoflagellates Plankton with two flagellae.
Down hole Down a well. The expression covers any equipment, measurement, etc. In
a well or designed for use in one.
Dynamic Positioning Use of thrusters to maintain a vessels’ position without the use of
anchors.
Environmental aspect An activity that causes an environmental effect.
Environmental effect Any change to the environment or its use.
Flagellae A long projection from a unicellular or multicellular body that aids the
movement of the organism.
Flowline Pipe through which produced fluids travel
Greenhouse gas Gas that contributes to the greenhouse effect. Includes gases such as
carbon dioxide and methane.
Greenhouse effect The greenhouse effect results in a rise in temperature due to infrared
radiation trapped by carbon dioxide and water vapour in the Earth’s
atmosphere.
Infauna Benthic organisms that live within the sediment.
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