Kevin McCallum, THE PRESS DEMOCRAT
A huge underground tank full of toxic black sludge in downtown Santa Rosa should be left where it lies because it is too difficult to safely remove and poses little threat to neighboring Santa Rosa Creek, according to the Pacific Gas & Electric Co.
The utility has also concluded that the contamination on the site of its former manufactured gas plant is immobile enough that it does not need to install a costly barrier designed to prevent waste material from migrating toward the creek, arguing it would be too disruptive and unnecessary.
The hands-off approach outlined for the Santa Rosa City Council last week represents a departure from the aggressive cleanup efforts that PG&E has undertaken on the property in recent years, which have resulted in the removal of tons of similar material.
But PG&E’s environmental consultants say the new strategy is justified because years of water-quality monitoring data shows that neither groundwater in the area nor the creek are at risk of contamination.
“The stuff is immobile. It hasn’t gone anywhere over the past 100 years and we have over 25 years of data,” Max Reyhani, principal engineer with Terra Pacific Group, told the council. “I think that’s a pretty good indication of the stability of site conditions.”
PG&E’s latest plan still needs the approval of the North Coast Water Quality Control Board, which has been overseeing cleanup of the property for nearly 30 years. The City Council, which has no direct authority over the cleanup of the site, has requested regular status reports on the downtown project.
Water board staff expressed confidence that continuing to monitor groundwater in the area made more sense than requiring the removal of the tank and material at this point.
“With the monitoring, I am extremely confident that we’re not going to have an issue that actually manages to migrate to the creek (over the next decade),” said Craig Hunt, supervisor of the water board’s cleanup division.
But not everyone is so sanguine about the situation.
Allen Hatheway, author of a 2012 textbook on the subject of cleaning up former gas plant sites, called the claims that the tank can’t be removed “nonsense.”
Read more via PG&E: Toxic tank in Santa Rosa best left | The Press Democrat.