In New Milford, a vacant, 300,000-square-foot brass mill is gradually deteriorating as an engineering firm prepares an estimate of how much it will cost to tear it down and make fit for reuse the 72-acre property on which it sits.

In Redding, workers are preparing the site of a former wire factory for development of a mixed-use complex that town leaders envision will one day include a thriving combination of apartments, shops and restaurants.

In Newtown, asbestos and other hazardous materials have been stripped from six buildings that were once part of a sprawling state hospital, and economic development officials are looking for businesses interested in renovating them for their own use.

And in Danbury, land where generations of workers built the city's reputation as the hatting capital of the world is nothing more than an overgrown lot, the factory that once occupied it vanished like the industry itself.

Century Brass in New Milford, the old Gilbert & Bennett factory in Redding, and the Mallory Hat factory in Danbury are brownfields, decaying legacies of the manufacturing industry that was once the backbone of the region's, and the nation's, economy.

But along with the campus of the Fairfield Hills Hospital in Newtown, they also represent benchmarks in efforts to restore the properties to productive use, this time cleansed of the contaminants that for years drove potential occupants to unpolluted, more easily-developed sites in the suburbs and left municipal leaders to deal with the economic and environmental fallout.

As Connecticut, and the rest of the country, struggle back to economic health, brownfields are seen as one of the most stubborn obstacles to successful redevelopment of communities scarred by their toxic legacy.

"Often, these are sites that are lying idle in the middle of a downtown area and are a blight on the community," said Pat DeRosa, remediation supervisor for DEEP's northwestern district.

"Developing them puts them back on the tax rolls and prevents the development of greenfields, (previously unused lands ) outside these communities and also saves the cost of extending infrastructure to the new sites," Ms. DeRosa said.

how many brownfields?

The Connecticut Department of Energy and Environmental Protection's brownfields inventory lists 281 locations across the state where remediation is necessary to restore abandoned or under-utilized properties to productive use.

While the majority are in cities where most factories were built, others are located in suburban communities, such as Redding and Newtown.

But DEEP's list is by no means definitive.

Other agencies involved in brownfield redevelopment, including the federal Environmental Protection Agency and regional development groups, don't always agree on the numbers. The Connecticut Brownfield Redevelopment Authority lists 190 sites.

Some authorities say the estimates are low and the actual number of polluted sites is much greater.

"We don't know of every brownfield site," Ms. DeRosa said. "A site could be active one day and abandoned the next."

The rules are different now than what they were years ago, said Elizabeth Stocker, the Economic and Community Development director in Newtown, who has helped lead the town's efforts to rehabilitate the buildings at Fairfield Hills.

"It's likely," she said, "there is a brownfield in nearly every community that has an industrial history."

Under state law, the buyer of a contaminated property is responsible for cleaning up contaminants, something that could potentially cost millions of dollars.

Without federal or state funds to aid the cleanups, developers and owners often walk away and build on clean land elsewhere.

competition for funds

Newtown acquired the former state hospital, which closed in 1995, and over the past several years, has rehabilitated some of the buildings to include a new municipal center and recreation facilities.

Beginning in 2005, the town received several grants, ranging from $150,000 to $200,000, which allowed officials to determine how much it would cost to remove the contaminated material, then pay to have the work done.

"It's a very competitive process," Ms. Stocker said. When the town received the most recent grant from the EPA earlier this year, there were more than 200 applications from across New England for the 17 that were eventually awarded, she said.

Officials envision several of the smaller, 4,000-square-foot buildings as office space, Ms. Stocker said, while a larger building would be an ideal location for a restaurant.

New Milford Mayor Pat Murphy said the town is using a $60,000 grant to determine the cost of removing the 300,000-square-foot Century Brass facility that former Economic Development Supervisor Vin Nolan has called the town's "industrial albatross."

The grant was a small slice of the $16 million package of loans and grants awarded by the state in March for brownfield projects.

"There is a renewed commitment for brownfield redevelopment in Connecticut," Catherine Smith, commissioner of the Department of Economic and Community Development, said at the time. "Cleaning up these sites so they are ready for redevelopment is vital to our efforts to spur economic activity and make our communities more vibrant and accessible."

In New Milford, the 72-acre site previously had undergone a multi-million dollar cleanup, including soil remediation work and removal of the ponds that held decades of chemical sludge, but as the building continues to deteriorate, fresh pollutants, including asbestos from the decaying roof, are contaminating the building, Mayor Murphy said.

There have been previous attempts to sell the property, most recently in 2010, but the mayor said demolition of the building will make that task easier.

Redding was similarly successful in obtaining money that enabled them to clean up the old wire mill in Georgetown and allow Georgetown Land Development Co. to develop the 55-acre site.

Crews are now relocating a road and doing soil remediation work on the property, Redding First Selectman Natalie Ketcham said.

"It's certainly moving us in that direction," Ms. Ketcham said. "It may be one of the few (brownfield cleanups) that are actually in progress."

old hat factories

In Danbury, attempts to develop the former Mallory Hat Co. factory on Rose Hill Avenue and an adjacent site on Barnum Court that once housed another hat factory have been at a standstill for years.

In 1997, the city obtained $200,000 from the EPA to determine the cost of removing mercury, lead and other contaminants.

Former city Environmental Director Jack Kozuchowski said the cost of remediation was estimated at about $600,000, adding that the cost has likely risen since that assessment was completed.

The lack of movement frustrates Jordan Young, president of Fairfield Processing, a manufacturing plant that has been in the city since 1940 and occupies land next to the now vacant lot.

Mr. Young said his company, which makes a fiber filler used in stuffed toys and a variety of home decor products, has long been interested in acquiring the property to expand its operations and workforce, but has repeatedly been told the city is not interested in selling it.

"We look at the vacant lot every day. It's a great site and it would be great to expand there," Mr. Young said.

Danbury Mayor Mark Boughton said the city has been in talks with Fairfield Processing for years and will consider a fair offer.

"We think it would be a good fit with Fairfield Processing," Mayor Boughton said last week, "and that's why we haven't been marketing it that hard."

Nearly every site the city has developed in the downtown area, including the new police station on Main Street, was a reclaimed brownfield, Mayor Boughton said.

Because the city has been around for so long -- since the 1600s -- there is bound to be some pollution, including ash, mercury and arsenic, he said.

But, Mayor Boughton said, removing contaminants from the old hat factory sites may not be as expensive as the earlier estimate.

"Technology has changed, it's actually gotten cheaper," the mayor said.

But eventual development of the properties, either for housing or for commercial use, won't be possible, he said, without either state or federal funding.

jpirro@newstimes.com; 203-731-3342