Cal/OSHA ordered Tesoro, the San Antonio-based company that owns the plant, to shut down the section where the incident occurred. What they've asked the company to do - 'review it's operations', show how it protects workers against spills and conduct refresher training - seems like weak tea, especially given the history of this company.
From the San Francisco Chronicle:
The Chemical Safety Board's interest in Tesoro's operations heightened in April 2010, when an explosion at the company's Anacortes, Wash., refinery killed seven workers.

In a draft report issued last month, the federal board said Tesoro had a lax approach to safety, which had led to "catastrophic consequences."

Tesoro required "proof of danger" before it would make safety improvements, the agency said in the report.
But now - surprise! - Tesoro is not allowing Chemical Safety Board inspectors back into the Pacheco plant.
Tesoro, based in San Antonio, downplayed the incident and said it was not satisfied the federal board had the right to intervene.

Elizabeth Watters, a company spokeswoman, described the incident as a "minor chemical release" that left the two workers with "minor chemical burns."
This is the second incident of chemical burns in this plant since November of last year. In the February incident, Tesoro hadn't issued the workers the equipment required by law to protect their faces and bodies from acid burns.
US inspectors were allowed access to the refinery after the February incident, but Tesoro is not allowing them further access despite requests from the Chemical Safety Board.

No regulators, no problem!

We'll see where this goes, but my god, the arrogance is astonishing.