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warm season plants - (3) plants whose major growth occurs
during the spring, summer, or fall and are usually dormant in winter.
See also cool season plants.
waste rock - (1)(a) the barren rock in a mine; (b)(2) the
ore deposit that is too low in grade to be of economic value at
the time, but can be stored for later processing if it becomes economically
feasible; (4) rock with insufficient amounts of economically valuable
elements to warrant its extraction, but which has to be removed
to allow physical access to the ore. Waste rock is typically blasted
into smaller particles to allow its removal by truck and shovel.
Disposal occurs in subaerial or subaqueous surface dumps or backfill
to open pit or underground workings. In heap leaching, spent
ore is sometimes referred to as 'spoils', 'gob', or 'rejects', terms
which also can apply to waste materials from density separation
and the wash plant.
waste rock dump (spoil pile) - (2) the area where mined
waste rock or spoil materials are discarded.
water balance - (4) a term used to describe an inventory
of the drainage inputs and outputs, water volumes, and the rate
of flow.
water quality - (4) chemical and physical properties defined
by measurable attributes of water, sediment and aquatic life.
water table - (4)(a) the elevation at which fluid pressure
is equal to atmospheric pressure. The surface separating the vadose
zone (where water is held under tension) and the saturated zone
(where fluid pressures are greater than zero); (b) the level to
which water will rise in a well just penetrating the saturated zone.
watershed - (3) the total area above a given point on stream
that contributes runoff water to the streamflow at that point.
weathering - (4) the process by which particles, rocks and
minerals are altered on exposure to surface temperature and pressure,
and atmospheric agents such as air, water and biological activity
wetlands - (2) areas that, under normal circumstances, have
hydrophytic vegetation, hydric marshes, and wetland hydrology. It
includes landscape units such as bogs, marshes, and lowlands, covered
with shallow ephemeral or intermittent waters. Permanent
waters of streams and water deeper than 9 feet in lakes or reservoirs
are not considered wetlands; (4) land where soils are water saturated
for a sufficiently prolonged period of time such that excess water
and resulting low soil-oxygen levels are the principal determinants
of vegetation and soil development. Jurisdictional wetlands are
described based on hydrology, presence of hydrologic soils and vegetation.
widowmaker - (1) a compressed air drill.
wilderness area - (3) a congressionally designated area
of undeveloped federal land retaining its primeval character and
influence, without permanent improvements or human habitation, that
is protected and managed to preserve its natural conditions and
that (a) generally appears to have been affected mainly by the forces
of nature, with human imprints sustantially unnoticeable; (b) has
outstanding opportunities for solitude or a primitive and unconfined
type of recreation; (c) has at least 5,000 acres or is large enough
to make practical its preservation and use in an unimpaired condition;
and (d) may also contain ecological, geological, or other features
of scientific, educational, scenic, or historic value.
winter range - (3) range that is grazed during the winter.
See also summer range
winze - (2) a vertical or inclined opening, or excavation,
connecting two levels in a mine, differing from a raise only
in construction. A winze is driven downward, and a raise is excavated
upward.
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