AMHERST – If they have their way, Amherst town councilors would see property at Hampshire College become a mixed-use development with young families living next to seniors, some business and the preservation of the pool and tennis courts. “My nightmare would be a sterile subdivision,” Councilor George E. The Amherst Town Council held one of its first meetings to prepare for the sale of the property as the school heads for closing at the end of the fall semester and sells its land to pay off loans. “One of my concerns is nothing happens. We can’t coalesce around a vision or we can’t spend the money on infrastructure,” Councilor Andrew Churchill said. “Another concern is it would be sold for a nontaxable religious or education entity and we would not get any benefit out of it.” MassDevelopment is providing assistance to help the town prepare to get the best use out of the college’s 800 acres of property, more than 600 of which are in Amherst, with the rest in Hadley. Monday’s meeting was mostly a discussion with the 13 town councilors.