A sump is a low space that collects any often-undesirable
liquids such as water or chemicals.  An example is the oil pan
of an engine. The oil is used to lubricate the engine's moving
parts and it pools in a reservoir, known as a sump, at the
bottom of the engine. Use of a sump requires the engine to be
mounted slightly higher to make space for it. Oil in the sump
can surge during hard cornering, starving the oil pump; for
these reasons, race engines are "dry sumped" using scavenge
pumps and a swirl tank to separate oil from air which is also
sucked up by the pumps.  One common example of a sump is the
lowest point in a basement into which any water that seeps in
flows. If this is a regular problem, a sump pump that moves the
water outside of the house may be used. If the building is a
nuclear power plant's reactor housing, the role of the sump will
be to collect any overflow of primary loop coolant; in this
case, monitoring and pumping of the sump is an important part of
the reactor's safety system.  Another