Other than dealing with resource management for the players, the Arks' denizens will show discontent if the players keep providing resources to the neighboring city instead of focusing on preserving the Arks' seedlings, even if there is a surplus.
In half of the chances for entering the city, the site will become a source for Steam Cores, which cannot be manufactured in your city.
A Wall Drill is probably enough for the first 10 days.