It happened last Thursday at a facility on Page Mill Road.
Twelve gallons of sodium hydroxide ended up going into a storm drain that flowed into a creek.
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Sodium hydroxide is used as a coolant, but the city says it is not hazardous to people's health.
The cleanup is still going on a week later and there's this: Palo Alto says Tesla did not have a permit for storing the chemical.
This means it could face a fine and have to pay for the cleanup costs.