Heater cores are located inside the passenger compartment, and a leak there would explain the antifreeze appearing on the floor near the gas pedal. The leak near the engine could be related to a connection point, or possibly a very significant crack in the heater core's inlet or outlet hose where it connects to the engine's cooling system. This is because the heater core is part of the engine's cooling system.
While other possibilities exist (though less likely given the location of the leaks), a bad heater core is the most probable cause. You'll need to have it replaced; it's a fairly involved job requiring dashboard disassembly.
