The city of Stockton will pay more than $60,000 in fines for releasing thousands of pounds of ammonia per day into the San Joaquin River from the city’s water treatment plant.
From the beginning of December to the end of January, the city racked up 16 Group 1 Serious Violations from the Central Valley Water Board. The violation is defined as pollutants exceeding the effluent limit by more than 40 percent.
Stockton’s treatment plant violated the maximum daily limit for ammonia in its discharge water 20 times during the monitoring period. Both its monthly averages were beyond the state’s limits as well. Stockton released 1,435 pounds of ammonia per day into the San Joaquin River in January, far outpacing the state’s limit of 917 pounds per day. The violation occurred during the third, and final stage of the sewage water’s treatment. Microbiotic agents are introduced to the ammonia-treated water during this stage and feast on the chemical. However, a prolonged cold snap from late November through December killed the organisms and resulted in potent levels of ammonia in water released into the river.
“The reality is the system is not designed for prolonged cold,” said Jeff Willet, interim utilities director for the city of Stockton. “We are in the process of redesign so we can handle these periods in the future.”
Stockton will not challenge the $63,000 fine, he said. There were also a few violations in February related to the situation that will bring fines on the city at a later date, he said.
Stockton’s wastewater plant provides sewage service for the city, the Port of Stockton and the surrounding unincorporated area.
The California Department of Corrections is also facing a $18,000 fine for dumping contaminated water into the Delta. The fine stems from violations at the CDC’s Deuel Vocational Institution in Tracy. The location released water with too much dissolved salts into the Sacramento-San Joaquin Delta six times between September and February. The institution also violated a nitrate limit in the released water one time.
The salinity violations occurred because the center’s reverse-osmosis system was corroded and couldn’t be used. The system is being repaired and will be back online by the end of the month, said George Paul, public information officer for Deuel Vocational Institution.
The Central Valley Water Board announced Tuesday that Stockton and the CDC are two entities included in a series of penalties totaling $315,000 being imposed across the Valley.
The State Department of Parks and Recreation is subject to the biggest fine, $120,000, for 40 violations of effluent limits for arsenic, turbidity and total suspended solids at Empire Mine State Historic Park.
Despite the number of serious violations for Stockton, Willet said the infractions aren’t cause for alarm. The water was in its final stage of purification, he said, and the city is working on correcting the issue.
“We brought the system online three years ago,” he said. “This past year we found out we need to make it better.”
Contact reporter Jordan Guinn at firstname.lastname@example.org.