The company has sent letters to the property owners but has not made definitive price offers, Jeff Smith told the Los Angeles Times.
"Some folks have called us back wanting to know more. But we haven't made any offers yet," he said Tuesday. "If people are interested in selling, we're interested in buying. We're prepared to buy all 100 properties."
Brockovich, working for lawyer Ed Masry, documented hexavalent chromium contamination in the water supply in Hinkley, an unincorporated community in the Mojave Desert. The story became the subject of the movie "Eric Brockovich," starring Julia Roberts and Albert Finney.
In 1997, PG&E agreed to settle with 660 Hinkley residents for $330 million.
The Lahontan Regional Water Quality Board says the contamination has spread beyond a boundary set by PG&E in 2008.