The town of Crockett has been battling a rotten egg smell for weeks that has prompted a health advisory issued by Contra Costa County Health Services.
The issue traces back to the Crockett Wastewater Treatment Plant, which is owned by C&H Sugar. The company said operational issues at the site are increasing the levels of hydrogen sulfide in the air, creating a very unpleasant smell.
Hundreds of complaints led to an on-site investigation by the Bay Area Air Quality Management District.
"We've also issued 16 notices of violation for public nuisance over the past couple of weeks and another one for unpermitted equipment at the site," said Kristine Roselius, Bay Area Air Quality Management District spokesperson.
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Health officials on Friday said the gas levels have dropped below the threshold that prompted last week's health advisory. The advisory will remain in effect through the weekend due to the length of exposure, officials said.
The site operator said they are working to fix the issue within the next 10 days.
The county said there is not much data on the impact of long-term exposure to the gas, but since you can become desensitized to the smell, it is important to look out for symptoms such as nausea, headaches, or irritated eyes.
The John Swett Unified School District said carbon filters provided by the county are being used in classrooms since masking does not help. School officials are hopeful the problem gets fixed sooner than later.