Arden Hills has approved the creation of a 427-acre town center megaproject, decades in the making, on the site of a former munitions plant.

The City Council did so in the face of pleas to hold off from its two leading vote-getters in the November elections, who unleashed a torrent of misgivings about what might happen down the road.

But Mayor David Grant, reflecting the feelings of the majority, spoke of the decision Monday as "an important step forward toward an amazing future" by bringing the long-abandoned site "back to life in a way that is good for the entire city."

The Rice Creek Commons project, also known as TCAAP — short for the Twin Cities Army Ammunition Plant that was built just before World War II — aims to create a mini-urban village with buildings as tall as 10 stories, surrounded by suburban-style single-family neighborhoods that are linked by parks and trails.

Susan Evans, speaking for master developer Alatus LLC, thanked "Arden Hills City Council, city staff and the residents of Arden Hills for their time, dedication and ongoing support of what we know will be a vibrant, welcoming community for many years to come."

However, Council Member Brenda Holden, the voters' favorite candidate in the last election, accused her colleagues of failing to conduct the "due diligence" required for a project that's expected to draw hundreds of millions of dollars in investment.

She attacked the plans on grounds that included the micro-sized living units permitted in some spots — smaller even than efficiencies — and the number of senior units, which she said may not create the street-level vitality city officials would like to see.

Steve Scott, who will join the City Council next month and received the second biggest number of votes, invoked the specter of troubled north-metro projects, such as the Vadnais Sports Center and Ramsey Town Center, then added:

"I do ask this council to delay final approval until it is absolutely certain all risks have been properly mitigated, and in my professional opinion" — he has experience as a public-sector project manager — "they have not."

The critiques signaled that a council more divided than the current one will guide the project from here on out.

Grant, on the winning side of the 4-1 vote to approve the master plan, reminded the council that a number of steps remain, including approval from other government entities.

"At some point, there's such a thing as 'analysis paralysis,' " he said in response to calls for more research. "We have discussed this for years."

The vote came very late on Monday night after prolonged debate, but council members noted the historic nature of the moment.

"One reason there is an Arden Hills," said Dave McClung, "is that our forefathers were looking to the development of this land. Another city coveted it; and I think [those forefathers] would be happy with the results we achieved tonight."