A development company with a history of transforming obsolete facilities has purchased one of the largest industrial sites in Alexandria and plans to build housing, office space and retail, granting residents new access to a large swath of the Potomac River.

The Potomac River Generating Station, a shuttered, 71-year-old coal-fired power plant, was decommissioned in 2012. Hilco Redevelopment Partners bought the site last week for an undisclosed amount after a 3½ -year pursuit. Pepco will continue to own part of the site to operate an electrical substation.

“We’re excited about the chance to reintegrate it into the surrounding urban fabric, open up that access to the waterfront and create a really dynamic district with world-class architecture,” said Melissa Schrock, the senior vice president of mixed-use development at Hilco. “We think the city of Alexandria deserves nothing less.”

Hilco will be guided by Alexandria’s 2017 Old Town North Small Area Plan and must include some affordable housing in the project, officials said. The site will include dining and public open space along the river.

The group recently redeveloped Sparrows Point in Baltimore, once one of the largest steel mills in the country.

“Development and development policy is the lifeblood of controversy in local government, but this is actually a pretty good example of a development effort that very few people are opposed to,” said Alexandria Mayor Justin Wilson (D). “Everyone’s pretty excited to see [the coal plant] go away.”

Schrock said the project could take five to 10 years to complete, depending on how long the company needs to conduct an environmental cleanup of the site.

The group also plans to make what it builds environmentally friendly. Hilco strives to reuse and recycle as much material as possible, Schrock said, with a goal of recycling 98 percent of the materials. It plans to work with the city to meet the goals outlined in the 2019 Green Building Policy.

Those goals include reducing energy use, mitigating greenhouse gas emissions and improving indoor environmental quality.

“I think we really envision that this is going to become part of an overall eco district, you know, trying to use some cutting-edge environmental sustainability components: district energy and geothermal and a lot of things that we haven’t seen much of in the city,” Wilson said.

The site has a long history. The plant was decommissioned after residents voiced their concerns about its impacts on health and the environment and prodded the city to get involved.

Elizabeth Chimento, a 78-year-old retired teacher, remembers attending a neighborhood civic association meeting in the early 2000s to ask about the gray residue she was seeing on her window sills, cars and patio furniture.

She said the Virginia Department of Environmental Quality and the plant manager at the time assured her that there were no contaminants floating around from the plant.

But she was unconvinced. She wrote a report that detailed the concerns she and her neighbors had with the Mirant power plant, its name at the time. She also called the city’s attention to a 2002 Harvard University article focused on small particulate matter generated by the five power plants in the Washington area, including the one in Alexandria.

“We said, ‘It’s the responsibility of the city to protect the public health of its residents,’ ” Chimento said. “The city took on the project. That was a wonderful thing because we didn’t have the money to finance all these studies ourselves.”

Alexandria formed a Mirant monitoring group, which conducted studies to document the pollution. The city made zoning changes designed to close the plant, over which the company sued. The city ordered the plant to do an environmental cleanup in the short term and close in the long term.

Hilco will publish an economic impact study soon, ­Schrock said, detailing the jobs that would be created through construction, engineering and consultancy, as well as permanent ones that would come in the offices, restaurants and other buildings.

Wilson called the plant’s planned transformation poetic.

“You’re taking a site that was a coal-fired power plant, which is about the most inefficient, non-environmentally sustainable way of generating power, and you’re going to turn it into hopefully some of the most environmental, sustainable development we’ve had in the city,” he said.