Passive containment cooling system

A pressure containment cooling system comprising:

• a reactor pressure vessel containing a reactor core therein submerged in reactor water, said core being effective for heating said reactor water to generate steam;
• a containment vessel spaced outwardly from said pressure vessel to define a drywell containing a non-condensable gas;
• an enclosed wetwell pool disposed in said containment vessel and partially filled with water to define a wetwell plenum thereabove, said wetwell pool having means for selectively venting said wetwell plenum into said drywell when pressure in said wetwell plenum exceeds pressure in said drywell;
• a gravity driven cooling system (GDCS) pool disposed in and vented to said containment vessel at an elevation above said reactor core and said wetwell pool, and including water therein and means for selectively channeling by gravity said GDCS pool water into said pressure vessel;
• and
• an isolation pool disposed at an elevation above said GDCS pool and containing an isolation condenser submerged in water, said isolation pool having a vent to atmosphere outside said containment vessel, and said condenser having an inlet line disposed in flow communication with said drywell for receiving said non-condensable gas along with any steam released from said pressure vessel into said drywell following a loss-of-coolant accident (LOCA), and further having an outlet line disposed in flow communication with said drywell for returning to said drywell both condensate produced upon cooling of said steam in said condenser and said non-condensable gas carried with said steam through said isolation condenser.