From Contra Costa Health:
Contra Costa Health (CCH) has lifted a health advisory in Crockett after air readings taken during the past two days no longer detected hydrogen sulfide in the air coming from the Crockett Wastewater Treatment Plant.
The health department will continue to monitor the situation even though we are lifting the advisory.
One-hour average readings taken by Contra Costa Health on Sunday and today at three locations in Crockett – John Swett High School, Carquinez Middle School and at Port and Ceres streets, close to the facility – came back negative for hydrogen sulfide.
Contra Costa Health issued its advisory on Oct. 7 after air-quality readings near the plant at 1801 Dowrelio Road in Crockett showed elevated levels of hydrogen sulfide, which created a rotten-egg or sewage odor in the surrounding area. The elevated levels of hydrogen sulfide were caused by an operational problem at the plant, which processes sewage from the community and wastewater from the C&H Sugar refinery. C&H owns the property and through a contractor operates the facility.
Representatives for the treatment plant said they have been able to mitigate the problem by draining and cleaning the plant’s reactors and improving air flow. The plant is also in the process of upgrading its equipment.
At no point did Contra Costa Health or its partners detect levels of hydrogen sulfide in Crockett’s air that would be considered immediately dangerous. Contra Costa Health issued the advisory at a point when air readings in Crockett showed concentrations of hydrogen sulfide above .03 parts per million, a threshold at which people may experience symptoms such as headaches, nausea, or burning eyes.
Crockett residents have made numerous complaints about odors caused by the treatment plant to local regulators such as the Bay Area Air Quality Management District. There have been no public complaints from residents since late Friday.
For information about treatment plant operations, contact C&H at 510-787-2121 or email@example.com..