Residents recently learned the pollution PG&E was required to clean up was once again moving and had seeped into the groundwater. Brockovich is now rallying residents over the concern.
Brockovich helped the town win a $333 million settlement against the company in 1996. The historic litigation spawned the blockbuster movie "Erin Brockovich."
The movie featured a housewife sick from toxic chromium, who in real life is Roberta Walker.
For Walker and others involved in the original case, these developments are like stepping back in time and are a haunting reminder that a landmark lawsuit and a blockbuster movie are no guarantee of safety.
While many of the more than 600 original Hinkley litigants moved away from the town after the 1996 settlement, Walker stayed. She preferred the remote desert landscape to a city skyline.
The Associated Press contributed to this story.