What type of cul-de-sac will be constructed at the end of Bellevue Avenue near the proposed roundabout?

That cul-de-sac will be a Hammerhead design, but with a slightly different orientation because the connecting road is rotated to near a 90-degree angle. A Hammerhead design features a T-shaped/Hammerhead layout that allows for vehicle turn-arounds but without a full circular area.