SAN RAFAEL (BCN) — Up to 3 million gallons of rainwater containing sewage might have spilled during two separate incidents since Friday, Ross Valley Sanitary District General Manager Brett Richards said on Thursday.
About 842,000 gallons of rainwater and sewage spilled out of manhole covers at College Avenue and Stadium Way and other locations in Kentfield, Richards said at a news conference at the district’s headquarters in San Rafael.
Officials discovered the spill at about 7 p.m. on Friday.
The district recovered about 105,000 gallons before the wastewater flowed into Corte Madera Creek and San Francisco Bay, Richards said.
During the cleanup, workers found large amounts of construction debris at the district’s pump station, Richards said.
Large pieces of asphalt, rubber from the running track at Kent Middle School, clay dirt, wire, and two hard hats were found at the site where JNB Construction, Inc., of South San Francisco, was working on a $4 million sewage system improvement project, Richards said.
“We are not alleging what might have happened, but it’s debris that should not be there unless it’s put there,” Richards said.
“The debris got into the sewer system through either severe negligence or malicious intent, but I’ve never seen negligence at this level,” Richards said.
JNB Construction has not returned Richards’ calls regarding the debris, he said.
JNB employees were on the spill site over the weekend, Richards said.
Richards said he contacted the FBI about the possibility that the
debris in the system was an act of “environmental terrorism.”
“I don’t know if they are going to get involved,” Richards said.
A second sewage spill Wednesday is being blamed on the failure of a 36-inch diameter Techite pipe under a berm along a jogging path, Richards said.
The amount of that spill “is as big or bigger than the Friday event,” and could be as much as 3 million gallons of wastewater, Richards said.
The district hopes to know by late today how much wastewater actually spilled on Wednesday.
The Techite pipe, a cement pipe lined with fiberglass, is known to fail and the one that ruptured Wednesday is 30 years old, Richards said.
According to Richard, no unusual debris was found in that failed pipe. “We don’t think the two events are related,” he said.
JNB Construction was not working on the Techite pipe replacement project, Richards said.
The Woodland-College-Goodhill project in Kentfield is the first project JNB Construction has done for the district in the last two and a half years, Richards said.
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