Patches of sticky silt--dubbed “goop” by environmental experts--have nearly tripled in size since their discovery three years ago south of the massive outfall pipes at the San Onofre Nuclear Generating Station and are smothering sea life along the ocean floor, a panel of scientists reported Wednesday.
“It kills whatever is below it,” said William W. Murdoch, a University of California biology professor who heads a three-member scientific panel charged by the California Coastal Commission with monitoring environmental changes around the plant.
But Murdoch, in an oral report to commissioners meeting in San Diego on Wednesday, stopped short of blaming the power plant for the spreading goop, and said the scientific panel is divided on what causes the sticky silt to form and smother a large kelp bed south of the outfalls.
Final Study Due in June
Although Murdoch said he personally believes that the evidence points to San Onofre’s water cooling system as the origin of the silt, the panel will not release its conclusions on the matter until it issues a final study in June detailing the environmental impacts of the seaside power plant.
That final study will culminate more than 14 years and $40 million in scientific research to chronicle the environmental changes around the intake and outfall pipes leading to the three reactors in California’s largest nuclear power plant.
The plant takes in 2 million gallons of ocean water every minute to help cool its nuclear reactors before discharging it back into the Pacific at temperatures averaging 19 to 22 degrees higher than the surrounding water, which ranges from 57 degrees to 68 degrees over the year.
Opponents of the plant have long predicted that the massive amount of hot water discharged by the cooling system would cause havoc in the nearby ocean, wiping out the vital supply of plankton and creating a “desert” along an area of ocean floor that once thrived with marine life.
Those concerns, plus a lack of hard data, prompted the Coastal Commission to form the three-member panel in 1974, when it granted a request by Southern California Edison Co. to expand the power plant from one to three reactors. Since then, the scientific panel has been studying the data and debating its significance.
Murdoch’s report served as a sort of prelude to the final scientific tome expected in June. Although incomplete, Wednesday’s update indicated that years of study have shown that the power plant has produced some environmental surprises:
- Despite the dire predictions of environmentalists, the water discharges from San Onofre have not wiped out the nearby plankton population. Composed of phytoplankton, tiny plants, and zooplankton, small animals drifting in the sea, the organisms form the foundation of the marine food chain.
Environmentalists had warned that most of the plankton would be sucked into the San Onofre cooling system and destroyed. What survived would be shot out in hot water plumes far out from the shore and left to die in inhospitable surroundings. Minus this food, clams, lobsters and mussels would disappear from the shore, creating a virtual ocean-floor desert, they claimed.
But Murdoch reported Wednesday that studies show the amount of zooplankton has remained unchanged around San Onofre, although the underwater intake pipes suck in nearly 1,000 tons of the tiny animals each year. The amount of phytoplankton has actually increased around the underwater outfall pipes, he reported.
However, one of the scientists on the panel took issue with the conclusions about plankton. Rimmon Fay, who represents environmentalists on the panel, said after the meeting that he disputes the way the panel tested for plankton, which was to take samples from areas of the ocean not directly affected by the San Onofre cooling water plume.
He claims the results are therefore misleading and that the plankton population has probably died off more than his colleagues realize.
- While the plankton are thriving, the scientists found that the power plant had a “major negative effect” on the population of midwater fish.
As far out from the plant as 3 kilometers, the number of queenfish and white croaker was found to decrease by 50% or more over the period that the three reactors were fired up.
Part of the decrease can be traced to the number of fish that are sucked into the cooling pipes and are killed, according to Murdoch’s interim report. Of the estimated 47 tons of midwater fish taken into the cooling system, 20 tons are killed.
Murdoch stressed, however, that these numbers are not enough to account for the drop in midwater fish population, a phenomenon the panel will continue to study.
- The population of bottom-dwelling fish, which include older queenfish and white croaker, actually increased to a distance of more than 1 kilometer from the plant. Total weight of the fishes increased by 60% to 100% during the 14 years of the study. The increase in bottom-dwelling fish was not a surprise, however, and had been predicted before the San Onofre expansion.
The keystone of Murdoch’s report, however, was the update on the goop, which he said is settling on a kelp bed just south of the outfalls. The bed, which measures 1 square kilometer, is of prime concern to the scientists and will be examined before the final report is released.
Murdoch told commissioners he believes the power plant is to blame for the sticky silt, which first began to show up in 1985, a year after the third reactor came on line. The patches of silt, which measure a meter deep in some areas, have spread on the ocean bottom.
After the meeting, Murdoch said he believes the goop was formed in the hot water plume coming out of San Onofre.
“The plume has small particles of dirt, and what I think may happen is that the turbulence by the plume combines small organisms with the inorganic material, to give it its cohesiveness,” he said.
He stressed, however, that his personal feelings are not the conclusions of the panel. Southern California Edison’s representative on the three-member board, scientist Byron Mechalas, told commissioners he believes the goop will prove to be a naturally occuring phenomenon.
“Some of our investigators have found that there is a clay outcropping on the edge of the kelp bed,” Mechalas said after the meeting. “What we think is happening is that this clay outcropping is covered with a layer of sand. Because of the shift in current with the seasons, this outcropping is eroding, it is being eaten away, and the sediment from the clay is spreading over the cobbles and coats the rock.
“That’s our theory of what’s happening . . . . It’s just something that we have started to notice,” he said.
Wednesday’s interim report about the environmental effects of San Onofre seemed to stir the coastal commissioners less than the $40-million price tag of the scientific study, which has been funded with Southern Edison money.
David Malcolm, a Chula Vista City Council member, said he was angered that the Coastal Commission spent the money on a scientific study when it could have used the funds to stop raw sewage pouring out of Tijuana and into the South Bay communities.
“I think it’s atrocious,” said Malcolm. “I don’t think the people are being served.”
The final scientific report will include further environmental studies not completed by Wednesday, including changes in the kelp bed, sand crabs and other marine organisms near the power plant.