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HollyFrontier Refinery


Final Water Tests Show No Oil in Mill Creek

Updated: September 20, 2012

Salt Lake City, Utah—The Holly Refinery explosion did not impact Mill Creek, according to the final results of water samples taken the following day when a storage tank ruptured and about 8,000 gallons of oil was sprayed a mile away.

The Utah Division of Water Quality collected water samples from Mill Creek the day of the August 30 incident to determine the presence of petrochemicals in the stream.

After visiting the impacted area, Walt Baker, DWQ Director, noted that, "The oil was very heavy and sticky. I had a difficult time removing the residue from my shoes. This stickiness makes the oil hard to clean up but also makes the oil less of a threat with regard to potential contamination of water."

DWQ scientists collected additional water samples from storm water collection areas on September 1 after a rain storm. Trace concentrations of petrochemicals were detected in these samples but the concentrations were below those that would affect people or aquatic life.

"We collected samples of spilled oil so that we would be able to identify if the petrochemicals in the water were from Holly oil as opposed to other sources such as oil from roads and parking lots. However, because the level of contamination we measured after the first rain was so low, and the number of contaminants so few, we didn't feel the need to analyze the Holly oil samples because it is unlikely that additional results would tell us anything new.” said Baker.

No additional water sampling is anticipated to be conducted by DWQ on this incident.


Holly Refinery Oil Explosion

Updated September 4, 2012

An estimated 200 barrels of oil were released after an explosion occurred at HollyFrontier's refinery in Woods Cross on Thursday, August 30. The eruption splattered oil into neighboring yards up to 1 mile southeast of the refinery. No injuries were reported.

Cleanup is ongoing and will likely take days. The company is working to prevent any residue from washing into nearby sewers and booms were placed in a cement-lined storm water diversion canal, just east of the railroad tracks. The Division of Water Quality collected water samples, with the results anticipated later this week.

"We can't allow it to run off into the drains, so we'll be collecting that material just so we can clean up the whole area," Mike Astin, environmental manager with HollyFrontier, told reporters Friday. "It will take a while to clean up, but we'll get it done."

The Department of Environmental Quality also took oil samples to determine the chemical composition of the oil. Meanwhile, refinery officials are telling people to thoroughly wash vegetables or throw them away.

A multitude of regulatory agencies have been contacted as a result of the spill, including DEQ, the local Health Department, and the Environmental Protection Agency, and the State's environmental remediation Division.

Astin said Friday the company believes water got into the heated tank and the resulting pressure "popped the roof on that tank." He told The Deseret News the oil in the tank is "much heavier than the motor oil in your car" and must be kept at 300 degrees to keep it liquid. Water turned to steam and created pressure that burst the tank. He estimated the refinery lost about 200 barrels of oil when the tank burst at 6:45 p.m. Thursday. By 9 p.m., a plan was created and crews went out to notify residents close by.

Health Risks of Oil

The risk of human and pet exposure to the oil may be minimal due to the fact that the oil dispersed in a large area. In any event, the key is to minimize the exposure. Garden food that has been exposed to the "oil droplets" should be thoroughly washed and the oil should be cleaned up wherever it can be reasonably done.

The health effects that can be caused by exposure to petroleum products or polycyclic aromatic hydrocarbons (PAH) depend on how much has entered the body, how long the exposure, and how the body responds to it. These effects may be either short- or long-term.

Short-term Health Effects

It is not clear that PAHs cause short-term health effects. Other compounds commonly found with PAHs may be the cause of short-term symptoms such as eye irritation, nausea, vomiting, diarrhea, and confusion.

Long-term Health Effects

Long-term health effects of exposure to PAHs may include cataracts, kidney and liver damage, and jaundice. Repeated skin contact to the PAH naphthalene can result in redness and inflammation of the skin. Breathing or swallowing large amounts of naphthalene can cause the breakdown of red blood cells.

Long-term exposure to low levels of some PAHs have caused cancer in laboratory animals. Benzo(a)pyrene is the most common PAH to cause cancer in animals. Studies of workers exposed to mixtures of PAHs and other compounds have noted an increased risk of skin, lung, bladder, and gastrointestinal cancers. The information provided by these studies is limited because the workers were exposed to other potential cancer-causing chemicals besides PAHs. Although animal studies have shown adverse reproductive and developmental effects from PAH exposure, these effects have generally not been seen in humans.

In Summary

PAHs generally have a low degree of acute toxicity to humans. The most significant endpoint of PAH toxicity is cancer. Increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs. Data for other sites is much less persuasive. It is difficult to ascribe observed health effects in epidemiological studies to specific PAHs because most exposures are to PAH mixtures. Animal studies show that certain PAHs affect the hematopoietic, immune, reproductive, and neurologic systems and cause developmental effects.

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