efficient way to obtain materials and hydrotransport them to on-shore processing
facilities, whether it be sand, gravel, or hard salt deposits.
Dredge pump It is a horizontal centrifugal pump designed to handle abrasive
granular materials and solids of limited size in suspension. They are distinct
from water and slurry pumps, which carry liquid and homogeneous mixtures,
respectively.
Dredge It is a piece of machinery used for removing materials that have been
partially or fully immersed under water, with the intent of collecting the sediment
and redistributing the content at a separate location.
Dredger It is the European term to describe a dredge.
Dredging It describes the digging or mining action used to collect sediment from
below the water surface. The gathered sediment is then either transported elsewhere or repurposed for other uses.
Drift eliminators Baffles, or other specialized collection products, placed in the air
exit path to capture water droplets. (Note: as per the previous mention of
scrubbing, again, mist elimination in scrubbing is a similar application.)
Drift Also known as windage, small droplets of water, which are carried out of the
tower by the airflow, normally expressed as a % of total water flow rate.
Drill A type of exercise that is a coordinated, supervised activity usually employed
to test a single specific operation or function in a single agency. Drills are
commonly used to provide training on new equipment, develop or test new
policies or procedures, or practice and maintain current skills.
Drone bee It is the sexually active male honey bee. Drones are most numerous
during the summer, but as food becomes scarce, the worker bees kill the drones
and remove them from the hive. A drone bee can only mate the female queen bee
once, and then die.
Dry bulb temperature Air temperature, measured by standard means.
Dryland farming A technique that uses soil moisture conservation and seed
selection to optimize production under dry conditions.
Dual Wheel Excavator (DWE) It is an Ellicott’s term for its patented underwater
bucket wheel excavator, also known as a Wheel Dragon™ excavator.
Earthquake The sudden movement of the Earth caused by the breaking and
shifting of rock beneath the Earth’s surface.
Eccentricity The extent to which the Earth’s orbit around the Sun departs from a
perfect circle.
Ecology It is a branch of biology that deals with the mutual relations between
organisms and their environment. Ecology implies more the webs of natural
forces and organisms, their competition and cooperation, and how they live off
one another.
Ecosystem Any natural unit or entity including living and nonliving parts that
interact to produce a stable system through cyclic exchange of materials.
Effluent Wastewater or other liquid—raw (untreated), partially or completely
treated—flowing from a reservoir, basin, treatment process, or treatment plant.
Elutriation The washing of digested sludge with fresh water, plant effluent, or
other wastewater. The goal is to remove fine particles and/or the alkalinity in the
12 Glossary of Natural Resources and Environmental Pollution Control
445
facilities, whether it be sand, gravel, or hard salt deposits.
Dredge pump It is a horizontal centrifugal pump designed to handle abrasive
granular materials and solids of limited size in suspension. They are distinct
from water and slurry pumps, which carry liquid and homogeneous mixtures,
respectively.
Dredge It is a piece of machinery used for removing materials that have been
partially or fully immersed under water, with the intent of collecting the sediment
and redistributing the content at a separate location.
Dredger It is the European term to describe a dredge.
Dredging It describes the digging or mining action used to collect sediment from
below the water surface. The gathered sediment is then either transported elsewhere or repurposed for other uses.
Drift eliminators Baffles, or other specialized collection products, placed in the air
exit path to capture water droplets. (Note: as per the previous mention of
scrubbing, again, mist elimination in scrubbing is a similar application.)
Drift Also known as windage, small droplets of water, which are carried out of the
tower by the airflow, normally expressed as a % of total water flow rate.
Drill A type of exercise that is a coordinated, supervised activity usually employed
to test a single specific operation or function in a single agency. Drills are
commonly used to provide training on new equipment, develop or test new
policies or procedures, or practice and maintain current skills.
Drone bee It is the sexually active male honey bee. Drones are most numerous
during the summer, but as food becomes scarce, the worker bees kill the drones
and remove them from the hive. A drone bee can only mate the female queen bee
once, and then die.
Dry bulb temperature Air temperature, measured by standard means.
Dryland farming A technique that uses soil moisture conservation and seed
selection to optimize production under dry conditions.
Dual Wheel Excavator (DWE) It is an Ellicott’s term for its patented underwater
bucket wheel excavator, also known as a Wheel Dragon™ excavator.
Earthquake The sudden movement of the Earth caused by the breaking and
shifting of rock beneath the Earth’s surface.
Eccentricity The extent to which the Earth’s orbit around the Sun departs from a
perfect circle.
Ecology It is a branch of biology that deals with the mutual relations between
organisms and their environment. Ecology implies more the webs of natural
forces and organisms, their competition and cooperation, and how they live off
one another.
Ecosystem Any natural unit or entity including living and nonliving parts that
interact to produce a stable system through cyclic exchange of materials.
Effluent Wastewater or other liquid—raw (untreated), partially or completely
treated—flowing from a reservoir, basin, treatment process, or treatment plant.
Elutriation The washing of digested sludge with fresh water, plant effluent, or
other wastewater. The goal is to remove fine particles and/or the alkalinity in the
12 Glossary of Natural Resources and Environmental Pollution Control
445