IGE conditions are usually found within heights about 0.5 to 1.0 times the diameter of the main rotor. So if a helicopter has a rotor diameter of 48ft, the IGE region will be about 24 - 48ft above the ground. 150ft above the ocean surface will be in an OGE condition and will require more power to maintain a constant altitude than if it was hovering at 15ft. Therefore a helicopter will always have a lower OGE ceiling than IGE due to the amount of engine power available. Mountains this high are common in Papua New Guinea for example.
Recirculation is a condition which can occur during a low hover in ground effect.
Imagine the airflow which was directed to the ground to create the air cushion in a ground effect is now rebounding off the ground and going back up into the top of the rotor system. When it passes back through the rotor again it gets accelerated. This process may continue with the air velocity increasing each time it passes through the rotor. Eventually the velocity is so great that the air going into the rotor from above causes a loss of lift and the helicopter will sink toward the ground unless the pilot increases power. This means that if recirculation is occuring, the helicopter will need more power to hold a constant height.