A Rocky Hill-based homebuilder is proposing to convert the a former high-security Webster Bank building in New Britain into a cannabis cultivation center.

CCC Construction wants to buy the 133,000-square-foot Webster Resource Center on Slater Road and remodel it for growing and commercially distributing cannabis.

The company was drawn to the building partly because it already has an extensive security system installed by Webster, which used it for storing and counting money. Security is a requirement for growing and distribution centers in Connecticut, and is a major expense for companies getting into the business.

But unlike two previous cannabis businesses that the city authorized this winter, the Slater Road project is hitting opposition from some nearby homeowners.

“There is no benefit to this facility being in our neighborhood, and only a detriment to our quality of living,” reads an unsigned letter that was distributed to several homes last week. “Surely the building could be used for something that brings more value to our city residents as it did years ago.”

Shelley Vincenzo of Robindale Drive identified the writer as a neighbor who didn’t want to be identified. In recent Facebook posts, Vincenzo posted the letter along with statements urging neighbors to turn out in opposition at a hearing next week.

“This is a residential neighborhood — it is NOT the place for this type of business. We need you to show up and speak out!,” Vincenzo wrote.

New Britain last year wrote zoning rules that would allow up to three marijuana-related businesses — retailers, commercial distributors or growers — in the city. Officials have already approved two applications, and the zoning board of appeals will hear CCC’s presentation Jan. 31 at 6 p.m. at city hall.

Vincenzo said when she asked last year about what was happening with the Webster property, Mayor Erin Stewart told her a cannabis distributor was looking at the site.

“Toward the end of last year, I noted the bank seemed to be gone. The signage was down, there were no cars,” Vincenzo said. “The mayor said someone wanted it for a distribution center. She never said anything about manufacturing.

“Then I heard they plan on manufacturing marijuana, and my whole perspective changed. That building is surrounded by houses, there are schools in the area,” she said. “The neighbors I talked to were shocked, nobody knew about this. I don’t think the mayor was transparent with us.”

Stewart said Tuesday that she’s been fully upfront about the project.

“I can understand how someone’s judgment would be clouded when they feel that their backyard is being impacted, but my office and city hall have been nothing but transparent through this entire process,” Stewart said.

Last year, the city solicited companies to put forward proposals for cannabis-related businesses, saying it wanted the “most well-developed models and community-focused visions.”

CCC was among the businesses responding. CCC would lease the property to at least two commercial growers. Co-owner Frank DiBacco said the proposed operation would help New Britain.

“Not only does the property satisfy the city’s need for safe and secure cannabis facilities, but applicant’s property would also contribute to the city’s economic development and grand list,” DiBacco wrote. “Such use secures a return on investment not only for applicant, but also the city and the local community by enhancing the city’s tax base.”

DiBacco noted that the building comes with perimeter alarm systems, closed-circuit video surveillance and monitoring systems, electronically operated gates, lockdown double doors, “and other advanced features intended to provide maximum security to the facility and its occupant businesses.”

Its large parking lot is “an optimal site for additional commercial and/or retail facilities. The parking area is large enough for at least three additional 5,000 square-foot buildings — each the ideal size for cannabis retail or hybrid-retail businesses,” according to his application.

One city document about the project says the Webster building is 700 feet from the nearest home, seven times what zoning requires.

But Vincenzo said she and many of her neighbors don’t want cannabis production or retailing nearby.

“I’m not against marijuana. I understand it’s the times we live in, but people have lived here 30 to 40 years, there are schools and homes here,” she said.