The process was supposed to start three weeks ago but it kept getting delayed because crews didn't have the necessary resources.
Now, crews will begin the removal of neutralized methyl methacrylate, also known as MMA, from two storage tanks at the facility on Western Avenue.
Methyl methacrylate is a toxic and highly flammable liquid used in the manufacture of acrylic plastics.
"The work will take place over several days in carefully managed phases, using specialized, temperature-controlled containers with multiple safety protocols." authorities said.
The operation is being coordinated by a unified command that includes the Orange County Health Care Agency, the South Coast Air Quality Management District and GKN Aerospace.
During the cleanup, people in the area may notice a fruity odor as teams begin to remove the chemicals from the storage tanks.
No evacuations are needed and officials say although the smell may be strong, concentrations of MMA are well below levels associated with health concerns.
The process is expected to take place through Thursday, July 2.
People will be able to monitor the air quality and track the cleanup effort online.
City News Service contributed to this report.