The Space Portal and The Sea

I want to take my Nuclear Thermal Propulsion (NTP) idea one step further.

A space portal situated on a shore would generate the required fuel for a space flight except for the mini-Nukes. Offshore wind turbines would be used to generate hydrogen and oxygen from the sea water to be used in the first stage of the rocket. Later stages would utilize the NTP and liquified air as the mono propellent. Liquified air would also be generated by the offshore wind turbines.

This space portal would only launch high energy missions such as Geostationary Satellite deployment, lunar and planetary missions. The second and later stages of the rocket are not recovered in those missions. Therefore, no risk of radioactive space debris to fall on Earth.

The first stage of the rocket would directly lift it to the ionosphere with no lateral speed. Then, the second stage would be fired and the first stage would free fall to Earth with parachutes attached. Due to vertical only displacement, the stage would fall close to the launch site where it would be recovered for reuse.

Emitting radioactive gas from the second stage above the ionosphere is not a big risk for the Earth. The ionosphere is bombarded with Sun's radiation and is already full of high energy particles. As the rocket increases its distance from the Earth, the risk would be reduced considerably. The magazines containing the mini-Nukes can be made of fire proof materials that can be safely recovered in case of an accident.