The Environmental Protection Agency says that an area larger than previously thought has been affected by the toxic chemical TCE at an underground Superfund site and has been "leeching into the air" in two specific spots, reported NBC Bay Area.
The area, located in Moffet Field and Mountain View in California, is roughly a mile and a half long and a half mile wide.
Superfund is a government program that addresses "abandoned hazardous waste sites," according to the EPA's website.
While the EPA cleaned the area previously, they now admit they missed a few "hot spots."
"What's most troubling about this news is that EPA officials admit they don't know how long this underground chemical plume has been leeching into the air of two different hot spots," said reporter Stephen Stock.
"The highest T-C-E levels that the EPA measured in ground water in the area reached 130,000 parts per billion. The EPA considers anything over 5 parts per billion unsafe," the NBC affiliate reported. The EPA says it will take decades to clean the groundwater.
“Once we found these concentrations, which were surprising, we took immediate action,” said Superfund Site Manager Alana Lee.
A California cancer organization found that residents who lived in the area had higher than normal rates of specific cancers between 1996 and 2005.
Since the EPA found the chemical in the air in two homes where residents may have been breathing it in for some years, it has finished a ventilation system for one home and is working on finishing the other.
It was also found in over 20 commercial buildings, include two new Google office buildings.
Watch the video, via NBC, below.