It is a thoroughly enjoyable movie. It appeals to my sense of justice, though nothing can restore the health to those people. Too many incidents like this, environmental contamination, have happended in America, and other movies have been made about them. Though I forget the title, there was one about milk and dairy cows contaminated by fertilizer. It starred Ron Howard and Art Carney.
Back to Erin Brockovich, my favorite part was the end when she got her bonus check. That part might be fictional, but it sure was funny.
Incidentally, the real Erin Brockovich is in the movie briefly. She plays the waitress at the beginning of the movie. I saw here on a story about the movie. She was portrayed accurately, including the way she dresses (even if Julia Roberts couldn't quite fill her shoes and other items of apparel).