Source: http://www.desertdispatch.com, June 20, 2011
By: Karen Jonas
The Lahontan Regional Water Quality Control Board released a draft order last week that would require Pacific Gas and Electric to provide whole-house replacement water for Hinkley residents who have been affected by chromium 6.
The current cleanup and abatement order requires PG&E to provide temporary bottled water to residents with chromium 6 tested at levels above the maximum background levels of 3.1 parts per billion or total chromium above 3.2 parts per billion, which is currently about 10 to 12 homes, said Lauri Kemper, assistant executive officer for Lahontan.
The draft order would require testing of homes about a mile from the 3.1 parts per billion boundary, said Kemper. The draft order would also require PG&E to provide replacement water for residences who have had significantly higher levels of chromium 6 in their water than in the past.
The water board is also in the process of selecting peer reviewers to evaluate a 2008 background study that shows Hinkley has naturally occurring chromium 6, said Kemper.
Several residents and activists have disputed the study and the water board hopes the peer reviewers will be done with their review by September, said Kemper.
Kemper said changes to the background study for chromium 6 could set new cleanup numbers and could require PG&E to cleanup the water to lower levels of chromium 6.
The water board has the authority to require PG&E to provide replacement water for residents who have water above the public health goal set by the Office of Environmental Health Hazard Assessment, said Kemper. The current draft health goal for chromium 6 is 0.02 parts per billion.
“We’re essentially relying on the draft of the (public health goal) as an assessment of public health,” said Kemper.
Jeff Smith, spokesman for PG&E, said Friday that the utility is continuing to work with the water board on the clean up efforts.
“We’re continuing to work with the water board and will certainly be responsive to their request,” said Smith.
The water board is asking for public comments on the draft order, including why whole-house replacement water is needed, what criteria should be used to determine which homes need the replacement water, and when PG&E should begin the replacement water program.
The chromium 6 contamination in Hinkley began after PG&E used the chemical to prevent rusting in cooling water tanks at its Hinkley compression station in the 1950s and 1960s.
The water was discharged into unlined ponds, where it slowly began seeping into the groundwater.
The plume of contaminated water is now about three miles long and nearly 1.5 miles wide. The water board has issued orders to PG&E requiring them to clean up the plume and stop the spread of contaminated water.