Lucky for Palo Alto residents, one of them who saw the spill called emergency responders.

The spill occurred at about 5 p.m. on Oct. 17, according to a hazardous spills report issued by the governor’s Office of Emergency Services. While the office could not say how much of the mixture was released and how much of it affected the creek, the Palo Alto Fire Department recovered 550 gallons of the mixture from the storm drain, the report stated.

This story has legs now because of shady business — Tesla doesn’t have permits required for the chemicals the city is now cleaning up.

While the incident occurred on Oct. 17, the city didn’t publicize it until this week, when community members began asking questions about the industrial activity around Matadero Creek, near Boulware Park. […] According to the city, the cleanup in this area concluded quickly but officials later saw damage east of the area, as the substance moved through the city’s storm drains. …according to the National Institutes of Health, sodium hydroxide is toxic by ingestion, corrosive to metals and tissue and may severely irritate skin, eyes and mucous membranes. […] According to the city, storage of sodium hydroxide requires a city permit, which the company had not obtained.

Lots of twists. The city says it was a quick cleanup of 550 gallons, but then Tesla says they only dumped 12 gallons, and meanwhile a week later the cleanup doesn’t seem to be over yet.

But let me speak to something especially odd about this story. If the liquid was indeed NaOH (sodium hydroxide), which the news correctly explains is highly corrosive to metal, then someone needs to audit the company’s safety practices.

A bright green color likely means a specialized liquid. The presence of sodium hydroxide suggests it could be an alkaline-based coolant, possibly with corrosion inhibitors and dye added for leak detection. Or there could be the presence of copper compounds from the cooling system’s metal components reacting with the alkaline solution.

While data centers typically use standard coolants like water with glycol or specialized dielectric fluids, Tesla may have been playing with a custom cooling solution to handle extreme heat generated by their AI chips. If this was indeed their approach, the choice raises serious questions about both the engineering decisions and safety protocols involved. This isn’t just a basic leak because Tesla actively using sodium hydroxide in a cooling system is baffling from an engineering perspective.

NaOH corrodes most metals, including aluminum and copper that are essential in cooling systems. Running corrosive coolant through metal pipes and heat exchangers under pressure is asking for trouble — it’s like filling your car’s radiator with drain cleaner and hoping it doesn’t catastrophically fail.

Even if they’d added corrosion inhibitors, the base chemical endangers both the infrastructure and the workers. The fact that no one caught this in safety reviews (and that Tesla lacked basic chemical storage permits) suggests their rush to build AI systems may be overriding fundamental engineering and safety practices.

The disaster is exacerbated by the delay in public notification, as people and pets could have been unknowingly exposed to contaminated water in Matadero Creek and around Boulware Park while Tesla and officials knew about the hazard. Even more concerning is whether Tesla has known for a long time, spilling before anyone was watching or reporting.