Health Advisory Lifted In Crockett

CROCKETT, CA — Contra Costa Health 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, it was announced Monday.

The health department said it would continue to monitor the situation even though the advisory was lifted.

"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 said Monday afternoon in a statement.

Contra Costa Health issued its advisory 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 were able to mitigate the problem by draining and cleaning the plant’s reactors and improving airflow. The plant was 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 said.

The advisory was issued 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 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, Contra Costa Health said.