Some voters asked that question during Monday night's special town meeting before ultimately approving the borrowing of $2.2 million over 10 years, at 0 percent interest, for the deal with the state Division of Capital Asset Management.
The vote was 248-14.
"I think it's a no-brainer to acquire the land, instead of having houses built there, as was originally proposed," resident Dexter Blois said.
Town Manager Jim Malloy showed voters a map, and said that a "survey is being done right now."
Hospital Road is wrong side of the map, for example, he said.
"There's going to be some slight changes to the survey," Malloy said.
"All you're really looking to do is get an adequate description so the borrowing can actually happen."
Resident Steve Doret said the town meeting warrant says about 95 acres are eyed for purchase, while the motion before voters was for about 90 acres.
"So, what happened to the five acres?" Doret asked.
Town Counsel Gregory Franks said town meeting's role is "to authorize action, and not necessarily dictate every little detail that will happen."
"There will be some changes to the survey that we're working on. And we'd like to not have to come back to town meeting if it does change, and it will," Franks said.
Earlier, Malloy noted that Westborough would have unrestricted control over the site's redevelopment.
Westborough and state officials would look to close the deal in June 2014, Malloy said.
Special legislation would be introduced by Thanksgiving, and passed by February or March, he predicted.
Westborough plans to maintain the 12 to 13 acres of soccer fields at the lower end of the property, Malloy said.
The land deal was among five warrant articles related to the state hospital.
The other votes were:
- Article 4 (special legislation for the purchase): passed, 230-3.
- Article 5 (land disposition): 226-4 (defeated, at the request of selectmen).
- Article 6 (creating a revolving fund for land sale revenue): passed, 215-11.
- Article 7 ($50,000 from free cash for land maintenance): passed, 217-7.