The department (DTSC), the regulatory agency overseeing Romic's operations in California, issued a consent order to the company regarding a June 5 hazardous materials accident at its Palo Alto headquarters.
At least four chemicals are known to have been mixed together, and a chemical reaction released a hazardous plume over endangered-species habitat near San Francisco Bay.
The order specifically cites Romic "for failure to operate the facility in a manner to minimize the possibility of a release of hazardous waste or hazardous waste constituents ... which could threaten human health or the environment."
Romic must submit a written report to DTSC within 30 days, detailing the company's preliminary findings and corrective actions, and submit a comprehensive report within 60 days. The order prevents Romic from adding bio-sludge into any fuel blending vessel and from accepting any waste containing the explosive chemical hydroxylamine until it has completed the written report.
Hydroxylamine, a reactive chemical involved in the June 5 incident, has been implicated in at least two non-Romic factory explosions since 1999 that resulted in injuries and deaths, according to various reports.
Romic spokesman Chris Stampolis said the company only accepts hydroxylamine in a diluted state.
Romic is looking into whether the concentration of the chemical it received from a company for waste recycling may have been greater than what it normally accepts. The accompanying manifest Romic received with the waste stated it was within the accepted range, Stampolis said.
Contrary to previous media reports, the chemical releases occurred in two locations: a fuel-blending tank on the Romic site; and a parked tanker truck, where the fuel blend had been loaded.
Two acres of land, including a PG&E substation, were originally reported to be covered with falling liquid from the plume; but that area has now been expanded to include more wetlands — including the Laumeister and Faber tracts, two large parcels of marsh owned by the City of Palo Alto, according to Janet Yocum, U.S. Environmental Protection Agency emergency on-scene coordinator.
Federal inspectors were investigating possible impacts on marshland wildlife Friday morning.
Two endangered species, the clapper rail and the salt marsh harvest mouse, live in the affected wetlands, according to Debbie Schechter, environmental and economic development coordinator for the City of East Palo Alto and a U.S. Environmental Protection Agency employee on loan to the city.
The chemical residue, a fine spray similar in appearance to black spray paint, is visible as a wide swath from aerial photographs. One of the chemicals, toluene, is on the state's Prop. 65 list of toxic substances, and is a high fire hazard that causes chemical pneumonia and reproductive abnormalities.
Methyl cyanide, a third substance in the accident, can be fatal if swallowed, inhaled or absorbed through the skin, according to industry data.
It is not yet known if the plume's residue has any toxic components, since it may have been chemically changed by heat during the chemical reaction, Wendy Chavez of the U.S. Environmental Protection Agency said.