SAN FRANCISCO -- A large hazardous waste dump in the agricultural Central Valley of California was fined more than $300,000 on Wednesday for failing to report 72 small spills over a four-year period, officials said.
The landfill's owner, Chemical Waste Management, kept records of the spills that occurred from 2008 to 2012 but failed to notify the state Department of Toxic Substances Control, the agency said.
The discovery by investigators that the company had failed to report some small spills led to a deeper inquiry that turned up dozens of violations, officials said.
There was no evidence that any of the spills posed danger to nearby residents or the environment, said Brian Johnson, the agency's deputy director of enforcement.
"We inspected the site, and also reviewed our monitoring of groundwater and air monitoring records for those periods," Johnson said in a conference call.
Yet much of the information gleaned about the spills came from the company, some years after the spill occurred, Johnson conceded.
Chemical Waste Management spokeswoman Jennifer Andrews said the company did not believe reporting the spills was a requirement of its permit.
The company said it has worked with the agency so its spill response is in compliance.
"We thought cleaning them up and recording them was all that was required," Andrews said in an email.
The hazardous waste landfill is the largest such facility west of the Mississippi River. It's located near Kettleman City, a farmworker community between San Francisco and Los Angeles.
Environmental groups have claimed the landfill contributes to periodic spikes in birth defects in the impoverished town. No link has been established, but residents have opposed the company's ongoing efforts to expand the landfill.
The fines were the latest in a string of violations at the site. In 2011, the federal Environmental Protection Agency and the state fined the company $1 million for problems with lab equipment used to measure chemicals in waste.
The state agency also fined the facility $46,000 in 2011 for two other spills.
Johnson said the state agency will look at the history of violations and other issues when determining whether to approve an expansion of the landfill.
Community members and environmental groups have been ardently opposed.
"It is time for the proposed permits to expand this terribly run toxic waste dump be denied, and their current permit should be revoked due to the serious, chronic and repeat violations" said Bradley Angel, executive director of the group Greenaction.
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