Mesa residents and city planners are scratching their heads over a proposal to convert a cluster of two-story apartments by Cliff and Loma Alta drives now serving about 490 tenants — mostly City College students — into three-story dormitories for as many as 1,500 students. According to city planner Dan Gullet, the proposal is now in the pre-application process. “We don’t really have anything like this,” he said. “It’s pretty unique.” Although the development company — landlord Ed St. George’s Unknown Dreams LLC — would serve City College students, it’s not working in partnership with SBCC, Gullet said. The project’s high densities would be achieved by eliminating individual kitchens and replacing them with dorm-style cafeterias, adding an additional story, and building 67 parking spaces, which is half the number of spaces now there.