NEW YORK (AP) — An industrial site in New York City that once was used to process radioactive material, including some sold to the government for the Manhattan Project, is still emitting worrisome radiation and should be designated a Superfund cleanup site, the Environmental Protection Agency said Wednesday.

The contaminated land in the Ridgewood section of Queens was the home, until 1954, of the now-defunct Wolff-Alport Chemical Company, which handled radioactive thorium extracted from monazite sand.

Today, the site is occupied by an auto repair shop, a warehouse, a deli and other small businesses. Environmental officials have long known about the contamination but didn't initially consider it a health concern. More recent radiation surveys indicated that some workers on the block may face a slightly elevated risk of getting cancer, particularly at the auto shop.

The EPA already has installed $2 million worth of radiation protections, including layers of concrete, lead and steel under building floors and sidewalks.

It also plugged up a hole in the basement of a nearby public school that was leaking low levels of radon gas into an unused storage room.

Now, the EPA is proposing to make the property the 87th toxic site in New York state to be included in the federal Superfund program.

Regional EPA administrator Judith Enck said it is too early to tell what kind of cleanup program might be required, but she said it "may very well involve a lot of digging" that could necessitate tearing down buildings, although she said every effort would be made to avoid that.

"These are all active businesses. There are people who go to work there every day," Enck said.

Wolff-Alport operated at the site between 1920 and 1954 and specialized in extracting rare earth metals. Originally, the company considered thorium a waste product and dumped it into the city's sewers until the Atomic Energy Commission ordered it to stop doing that in 1947, the EPA said.

A 2009 survey found radiation levels about 75 times higher than normal background levels. That's not believed to be dangerous, Enck said, but further tests and analysis led to a determination that workers at the auto repair shop, Primo Auto Body, could be exposed to a higher annual radiation dose than called for in federal safety standards.

The owner of the business, Alberto Rodriguez, said in a phone interview Wednesday that the work to install the radiation shielding already has cost him business. He said he was surprised to hear that a bigger cleanup might include demolitions.

"They don't tell me anything about having to move," he said.

Superfund Director Walter Mugdan said there's no reason to believe that students at the nearby Intermediate School 384, where the radon leak was found, are in any jeopardy. He said new tests had indicated that the gas was no longer entering the building.