The cleanup of the former Lexington Gardens site, 500 Middletown Avenue, is in its final stages after the recent removal of two subterranean fuel tanks, according to Building Official Dave Maiden.

The two tanks had been left underground during the property’s major cleanup phase in January, as the soil was frozen. A third fuel tank had been removed in January before the soil was too solid for further excavation. “The tanks were the last thing to do before they cleanup the whole site and grade it out,” Maiden said last week.

Maiden added that all three tanks were removed by New Haven’s McVac Environmental Services, which also tested the surrounding soil for contamination.

“There was no contamination when the tests came back,” Maiden said. A McVac Environmental Services representative refused comment last week.

With the last two tanks gone, the final stages of the site’s cleanup will be performed by Mineri Excavation of North Haven. A Mineri representative could not be reached.

The removal of the tanks came to light after an underground leak stopped demolition efforts on the property on Dec. 23. On that date Billy Brencher, assistant director of field operations for Public Works, reported the leaking of liquids from the site onto Middletown Avenue and Spring Road.

The fire department was called in to assess the December leak, and they determined that the liquid contained an indeterminate amount of oil. Property-owner Loretta Mufson hired McVac Environmental Services to remove the tanks.

The excavations of the remaining tanks were overseen by North Haven fire department Deputy Chief Frank Gersz.

“It all went well,” Gersz said. “There was absolutely no contamination.”

“I think the site is pretty much all cleaned up now except for junk on tops and bits of metal,” Gersz added. “I think Mineri is just waiting for decent weather to start raking it all out.”

The former Lexington Gardens greenhouse business at 500 Middletown Avenue, which included a factory and several large greenhouse structures on the 23-acre site, has been almost entirely leveled. Mineri began the original demolition efforts in July. However, a July 17 inspection by the Connecticut Department of Public Health and the Quinnipiac Valley Health District halted the demolition after toxic materials, including asbestos, were discovered on the site. The inspection also determined that the demolition had been started without prior notification to the DPH and without the payment of a $25 demolition fee.

In response, Mufson hired Abcon Environmental Inc. for the asbestos abatement, which the New Haven company completed in January.