April 7, 1926
Travel through the Midwest and every barn and silo has a lightning rod on it. Not too many around here. Thunderstorms are rare on the Central Coast, but a recent electric storm set me to thinking about the biggest lightning disaster in the region.
Union Oil built the tank farm along the road of the same name a century ago in 1910. It was a major storage facility for oil from Taft and Kern County on the way to the terminal in Avila Beach where tankers were filled.
Rain was in the forecast Wednesday morning when lightning struck between two massive underground reservoirs about 8:45 a.m. (A later story sets the time an hour earlier.) The resulting explosion quickly spread fire and now four reservoirs were ablaze.
More than 100 workmen waged a desperate battle to contain the blaze. They had no chance to quell a 75-foot-tall wall of flames.
Only three years earlier San Luis Obispo had retired its last horse-drawn water pump and had all of two fire engines to protect the city.
The four burning reservoirs were full with 3,250,000 barrels of oil. Two others in imminent danger held 1,250,000 barrels each.
Faces covered with black soot, workmen tried to protect the pump house and other smaller steel surface oil tanks with a wall of sheet metal but as steam in the burning tanks expanded flaming rivers of oil spread. The rush of oxygen to feed the fire was so intense that wind nearly drove them off their feet. Soot blackened rain drops fell in Santa Margarita.
The S.S. Montebello, the largest ship in the Union Oil fleet at the time was heading a flotilla of tankers steaming to Avila to offload oil. (The tanker would be sunk by a Japanese submarine in WWII off the Cambria coast.)
The first day story said that oil was being pumped to storage tanks in Avila Beach. The plan was that after tanks were filled the surplus would be pumped into the ocean in an attempt to starve the fire and save the expensive reservoirs not yet in flames.
Tar paper and splintered timbers fell from the sky after explosions ripped the roofs off of the reservoirs.
In town, late-rising folks were “blown out of bed” with windows breaking and plaster falling.
A.H. Seeeber, and his son W. F. Seeber weren’t so lucky. About 12:30 a.m. Thursday a second explosion rocked the area and their home near the oil reservoirs was crushed, caught in a cyclonic wind that uprooted trees. The elder Seeber was about 75 years old and the younger about 50.
Up to a mile from the Tank Farm toward Edna the whirlwinds scoured, crushing roofs like eggshells.
All of the large reservoirs were in flames by 1 a.m. though workmen tried to staunch the river of fire.
About this time Dr. H.A. Gallup, Lafe Todd and William Groundwater had to run for their lives when the walls of the warehouse they were in began to leak flaming oil.
Dr. Gallup abandoned his car when it would not start and he jumped in another.
“From there to the highway,” said Dr. Gallup, “it was a race with the flames. “It seemed that the tide of oil was flowing faster than we could get the machines to travel and it was not until we struck a slight ravine where the oil formed a blazing pool that we were out of the blazing zone.”
Three minutes later the warehouse and Dr. Gallup’s car were a total loss.
The second-day story compared the rim of the large reservoirs as being slightly smaller around than the football stadium at UC Berkeley though not as deep.
Burnt debris fell at General Hospital and Terrace Hill. A still-burning timber 1x8x16 fell out of the sky and impaled the ground near a home on Orcutt Road two miles away.
The Wilmot farm and livestock were destroyed.
Driven by steam oil flowed from the underground tanks with enough force to push flames uphill.
Operators at the telephone company were overwhelmed and had to add staff.
Union Oil had a similar conflagration when the same storm struck the town of Brea a day after San Luis Obispo. The value was about half the damage of the San Luis Obispo fire.
By Friday the Telegram got around to publishing its first photo of the blaze. One of the biggest stories of the century and it takes three editions to bury a photo at the bottom of the page.
This was the last local owner of the paper, and he ran a slate of ads on the front page and failed to get a photo until the third day. Not what I would call stellar news judgment.
Fresno radio stations said that smoke from the fire could now be seen there. White sheep in Santa Margarita were now a sooty black.
A steel tank caught fire Friday night and another Saturday morning, Sheriff Charles J. Taylor had to post deputies on roads in the area to keep the curious out of the danger zone.
In the end, six residences were destroyed and 10 other farms suffered damage in addition to two houses on company property and other Union Oil facilities.
By Monday the fire was practically out, only five of 19 steel tanks survived. Over 8,000,000 barrels of oil were lost.
If you didn’t get your copy of that paper, it may be still be at the post office. The postmaster sensed an opportunity to get folks to pay overdue postage and held the copies.
At the time the San Luis Obispo fire was the nation’s worst oil disaster but the company carried insurance. The book Unocal 1890-1990 a Century of Spirit, said the $9,000,000 Brea and San Luis Obispo insurance pay-out was the biggest since the San Francisco earthquake.
The environmental toll is still being tallied.
People walking the site can still find bits of fused glass the fire made from sand.
On Nov. 19, 2006, The Tribune published a story by its environmental reporter about the plans for the site.
By David Sneed
In April 1926, lightning struck the Unocal tank farm in San Luis Obispo, causing a spectacular fire with flames shooting 75 feet in the air, shattering nearby windows and releasing millions of barrels of flaming crude oil that spread across adjacent fields.
Witnesses said “the fiery oil, floating on the flooding creek, progressed all the way to the ocean at Avila. … Skeletons of burned trees lined the creek.”
Two people were killed.
Now, 80 years later, a long-term solution to the environmental problems caused by that disaster and a blueprint for how the strategically located land could be used are near at hand.
The site still poses a danger to wildlife because the decades-old oil bubbles to the surface in some areas during hot weather. The oil has decomposed to the point that it poses no threat to humans or the water supply.
Chevron, which now owns the tank farm, hopes to have a proposed cleanup plan by next summer. If approved, the 340-acre site would be opened to additional uses, including permanent open space, limited recreation and some commercial development.
If all goes well, cleanup work on the site could begin as early as summer 2008, said Chevron spokesman Gonzalo Garcia.
“Nearly a century has passed, and we are still dealing with contamination issues,” Garcia said. “It’s time we got moving on this.”
Release of the cleanup plan will trigger a full environmental review, including opportunities for public comment and participation, Garcia said.
The tank farm is located along San Luis Obispo’s southern boundary, and city planners have targeted all or part of it for annexation. With the oil pollution at the site and the area’s industrial zoning, however, residential development is unlikely.
A historic disaster
Built in 1910, the Unocal tank farm was a major storage center for oil pumped here from the San Joaquin Valley. It contained six large underground storage reservoirs as well as 21 above-ground steel storage tanks.
On April 7, 1926, lightning struck the facility during a storm and sparks ignited two of the large storage reservoirs. Steam generated by the fire caused the full reservoirs to overflow. The oil collected in low spots on the site, where it remains today.
At that time, it was one of the nation’s worst petroleum industry disasters. It was also the first of a list of high-profile Unocal oil spills in San Luis Obispo County.
Others occurred in Avila Beach and the Guadalupe oil field. These posed a higher cleanup priority and delayed the tank farm project.
In 2003, an interagency task force conducted an ecological risk assessment of the site and determined that the oil has decomposed and moved underground to the point where it poses minimal environmental threat.
“Basically, we found that some areas require treatment and some areas do not,” said Neil Havlik, San Luis Obispo natural resources director. “There are portions of the property that could be used for urban development, while others — the wetlands in particular — should remain as they are, even if they are contaminated.”
Over the years, sediment has covered the oil, which has turned into asphalt-like material. On hot summer days, some of the oil liquefies and bubbles to the surface.
This poses the biggest environmental threat, said Melissa Boggs-Blalack, an environmental scientist with the state Department of Fish and Game. Birds and other wildlife could become coated by the black goo.
To prevent this, Chevron has erected large nets around the seeps. The nets, as well as the berms from the storage reservoirs, are visible from Tank Farm Road, which bisects the facility.
Chevron also uses propane-powered noise guns and reflective tape commonly seen in vineyards to scare wildlife away from the seeps. One of the first priorities of the forthcoming remediation plan is to remove these seeps, Garcia said.
“Areas where birds and wildlife can be contaminated will be cleaned up, absolutely,” he said.
Over the years, the tank farm has evolved into an important habitat area. The earthen reservoirs and other low-lying areas are seasonal wetlands that attract a variety of waterfowl.
The wetlands are home to the vernal pool fairy shrimp, a federally listed threatened species, and a rare kind of tar plant. These are the site’s most fragile plant and animal, Havlik said.
Chevron has earmarked 50 to 60 acres of the tank farm site for light industrial development. This would take place on the western and eastern edges of the property adjacent to similar existing development on land owned by others. None of Chevron’s tank farm property has been developed, Garcia said.
Potential development areas include the current site of Chevron’s office buildings on the west side of the property near Farm Supply Co. and areas adjacent to existing development off Broad Street.
Cleanup of the property could also open it to some form of limited public recreation, such as hiking. However, protection of the wetlands and sensitive species should take priority, Havlik said.
“It would be some sort of a low-key recreation with an education component,” he said.
No estimate of the cost of the cleanup is available.