Behind the fence of the Santa Susana Field Lab are 2,800 acres of land that remain largely contaminated with radioactive and chemical waste.
It was back in 2015 that the I-Team's LA's Nuclear Secret investigation revealed how nuclear accidents since the 1950s, and thousands of rocket tests that occurred until 2006, left a stew of toxins in the ground and groundwater.
On Thursday, the State Department of Toxic Substances Control, or DTSC, released an environmental impact report, detailing a final cleanup plan that's been debated for decades.
"This is a major milestone because it opens the door to a full and final cleanup,” said Meredith Williams, the Director of the DTSC during an online forum attended by the I-Team.
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According to the state's plan, it will take 15 years to clean up the contaminated soil, and DTSC says it will be a full cleanup.
Not true, say longtime advocates for a cleanup. They say the state's the new plan violates 2007 and 2010 agreements between the state and the owners and users of the lab, Boeing, NASA, and the Department of Energy, to clean up almost all of the contamination.
"A terrible, terrible blow,” said Dan Hirsch, who has been fighting for a full cleanup of the lab for 44 years. Hirsch served as the head of the program on Environmental and Nuclear Policy at UC Santa Cruz.
He says the details and numbers of the state’s plan show most of the contamination would not be cleaned up.
"Ninety percent would not get cleaned up and 10% would,” according to Hirsch.
The DTSC didn’t respond to specific numbers and said cleanup levels will be finalized in the future, when asked by the I-Team.
But scientists say any amount of contamination is not safe.
"To understand the health effects, think cancer, birth defects, developmental disorders, and learning disabilities,” said Robert Dodge, from Physicians for Social Responsibility.
After unveiling its plan Thursday, DTSC says it will continue to welcome feedback from the public.
"Our goal is to fully and transparently engage with the public on this cleanup each step of the way,” said DTSC director Williams.
Residents living near the field lab say they'll continue to speak out and advocate for a more thorough cleanup of the contamination just above their homes at the Santa Susana Field Lab.
"It's been 34 years and I might not live long enough to see the cleanup, but we'll keep fighting for it because it matters," said Marie Mason, a Simi Valley resident.
The fight for a full cleanup could end up in court. The city and county of LA, and Ventura County, have all said they'll take the state to court to make sure a Santa Susana cleanup complies with those 2007 and 2010 agreements.