Mining pit cleanup earns Governor’s award |

Mining pit cleanup earns Governor’s award

For many years, the old Spenceville mine pit was filled with water as acidic as stomach acid.

And if some hiker in the Spenceville Wildlife Area had gone tumbling down into the acidic waters of the half acre-wide, copper mining pit, they might have had a hard time climbing back up its steep banks.

That horror-movie scenario is now a thing of the past, thanks to a $9 million, state-funded clean-up and restoration project completed early this year.

On Wednesday, the clean-up was among 14 recipients of the prestigious Governor’s Environmental and Economic Leadership award. At a ceremony in Sacramento, officials presented the award to the state agencies and private contractors involved.

The state hired Walker Associates, Inc., a Sacramento engineering firm, to oversee the project. Last year, the firm had a temporary water treatment plant built on site to clean up the pit’s water, which took about six weeks.

Then, workers mixed lime with the acidic, old mine tailings piled up nearby and used the mixture to fill the pit. Early this year, workers revegetated the site with native plants.

“It was very successful,” said Lara Christensen, an environmental scientist with Walker Associates, Inc. “It’s all been re-contoured and replanted. The creek running through the site has been restored to its natural path.”

State agencies receiving the award were the California Department of Fish and Game, the Department of Conservation, and the Central Valley Regional Water Quality Control Board.

The acidity in the old mine was naturally occurring. Back in the 1890s, tailings from the Spenceville Copper Mine were used to make “Spenceville Red,” a barn paint which initially won prizes for its brilliant hue, but later went off the market because the paint had a tendency to eat the heads off nails, reportedly causing buildings to collapse.

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