Lingering toxic chemicals in the groundwater and soil under 2274 Mora Drive is being blamed for the delay of the development of as many as 250 homes on a 10-acre site.
The plume of mostly Trichoroethylene (TCE) and Perchloroethylene (PCE) -- cancer-causing solvents left behind by 1960s electronic component manufacturer Plessey Micro Science -- has been a challenge for housing developers, two of whom have backed out of deals to develop the site since 2011, said Marty Chiechi of Grubb & Ellis, a real estate broker involved in the deals.
The city gave property owners on the site 25 years notice that the area would be redeveloped as housing in 2012. Over a dozen small businesses occupy buildings on the cul-de-sac, and many complained in 2012 that they didn't know about the deadline and did not have time to find other suitable buildings. Most remain.
At the start of 2012, the City Council granted housing developers another 18 months to develop the site, and last month the council gave another 18-month extension to developers.
The latest developer to give the site a shot, Lenar Homes, says that it has a workable plan to clean up the site.
"The environmental situation was something that required a lot of work," said Douglas Rich of Lenar Homes. "We have done a lot of military base conversions so we have a lot of expertise with environmental contamination."
The situation is complicated because of fears that there is still a source of contamination under the buildings, such as an undiscovered underground storage tank. "You never know until you demolish the building and see what's under the buildings," Chiechi said, adding that Lenar has set aside $1.6 million to deal with any unexpected problems and that the Department of Toxic Substance Control also has substantial funds for the cleanup, as Plessey Micro Science declared bankruptcy years ago.
"We are not sure if there is still a source of contaminants under the former Plessey building," said Russ Edmondson, media officer for the Department of Toxic Substance Control. According to DTSC reports, indoor air TCE concentrations were recently higher than the limits for plumes under residential buildings, even though "the soil vapor extraction system that Plessey operated for a number of years was intended to reduce concentrations," Edmondson said.
Despite that, no indoor air sampling has been done to make sure occupants are safe from TCE vapors, known to cause cancer and other health problems.
The fact that no indoor air testing has been done is "just not comforting," said Scott Simon of Simon Printing, which has occupied part of the Plessey building for 32 years. He added that he's never been informed about the potential health effects of TCE vapors either, even while toxic cleanup efforts have gone on for years around his building, and he says holes have recently been drilled on the property to inject substances into the ground that help break down the plume.
"Currently each unit of the building has an operating business in it. That's why we plan to collect (soil) samples once a developer removes the buildings," Edmondson said. "It would be easier and not interfere with the businesses."
Edmondson said housing developers would be required to place systems under the homes to prevent vapors from entering the new homes, as has been done in numerous housing projects near the Fairchild Semiconductor Superfund site on Whisman Road.