Hinkley chromium clean-up could take more than a century

HINKLEY • The Lahontan Regional Water Quality Control Board will be deciding soon if an expansion to the treatment of the chromium 6 water plume in Hinkley will be put into place, but residents probably won’t see the results in their lifetimes.

Pacific Gas and Electric is proposing to expand its current operation of injecting the chromium 6 tainted water with ethanol to convert it to the less dangerous chromium 3. In a feasibility study done by the water board, the ethanol treatment would probably take about 150 years to restore chromium 6 levels to the naturally occurring levels of 3.1 parts per billion.

The feasibility study done by the water board shows that the removal of the chromium 6 tainted groundwater will take more than 100 years, even with the most effective treatment.

PG&E is currently injecting ethanol into the plume in order to convert the chromium 6 into chromium 3, which is much less toxic. The company pumps contaminated water out and sprays it onto alfalfa plants so that it will not be spread through the air. PG&E also injects clean water as part of the program to cleanse the groundwater.

The expanded program will include increased pumping and will occur over a larger area, said Lauri Kemper, assistant executive officer for the Lahontan water board.

Kemper said the program was chosen out of five different alternatives because PG&E had tested a variety of treatments over the years, and the ethanol treatment worked best with higher concentrations of chromium 6.

The plume of contaminated water has been slowly growing and is now about two miles long and nearly a mile wide.

PG&E has been ordered by the water board to clean up the chromium 6, but the plume continues to grow.

Jeff Smith, a spokesman for PG&E, said PG&E was committed to the clean-up in Hinkley.
“We’ll do whatever is necessary to clean up the Hinkley area,” said Smith.

Carmela Gonzalez, a Hinkley resident who has been trying to get Hinkley’s water cleaned up, said that the proposed effort was not good enough.

“The public needs to say that over a hundred years is out of control,” said Gonzalez.

Gonzalez urged residents of Hinkley to attend a public information hearing that will be held on Wednesday

“The public needs to contact the water board,” said Gonzalez.

The Hinkley water situation became famous after legal aide Erin Brockovich helped win a settlement against PG&E worth $333 million for the residents of Hinkley who had been sickened by tainted water. The battle became the source of the Oscar-winning film “Erin Brockovich.”

PG&E used chromium 6 over fifty years ago to prevent rust in cooling water towers in Hinkley. The wastewater was discharged into unlined ponds, where it eventually seeped into the groundwater in Hinkley.

Chromium 6 has been shown to cause oral and intestinal tumors in rats and mice when ingested, according to studies done by the National Toxicology Program.

source: desertdispatch