September 28, 2010 | 2
Editor’s Note: Expedition Blue Planet, led by Jacques Cousteau’s granddaughter Alexandra Cousteau, is traveling 14,500 miles of road over 138 days to investigate and film some of North America’s most pressing water-use and management stories. Each week expedition members will file a dispatch from the field for Scientific American until the expedition concludes on November 12 in Washington, D.C. This is their third blog post.
It’s Wednesday and we’re at Ladd Landing just outside the town of Kingston, Tenn., packing our boats for a trip upstream to ground zero of the 2008 spill that dumped over a billion gallons of coal-ash into the unwitting Emory River. We’ve packed up our camera equipment, sound gear and apprehension for the ride.
The murky fog soup blanketing the river burns off to reveal sparkling water and blue skies. It’s a beautiful day," says Donna Lisenby, Upper Watauga River’s riverkeeper in North Carolina and the Emory River’s honorary riverkeeper seeing as it has none of its own.
"A beautiful day to do disaster investigation," Christoph Schwaiger clarifies wryly, camera in hand.
Lisenby paddled the Emory immediately after the spill. What she saw still haunts her. When she speaks about it her punchy voice rises as she gesticulates with urgency.
"Being here was like a war zone. There were helicopters flying overhead dropping straw and grass seed," she describes for us. "It looked like bombed-out craters."
She assembled the first independent group of scientists to test the water, post-spill. They found that the levels of arsenic and heavy metals were 100 times higher than that reported by the TVA and EPA.
The toll on fish, two years later
Today, the 10-foot-high piles of coal ash that rose out of the water are long gone (Lisenby dubs them "ashbergs") but we’re here to study how the aquatic ecosystem is still affected by the spill.
"Essentially we’re seeing an increase in the amount of selenium and arsenic in the tissues of these fish," says George. "Selenium is considered the silent killer."
Anna George, director of the Tennessee Aquarium Conservation Institute in Chattanooga, is out on the water with us to electroshock for fish at a couple of her study sites. Electroshocking is a common method of surveying fish populations by temporarily stunning them using an electric current. Fish in the vicinity of the zapped water float to the surface where they are scooped out of the water with a dip net and transferred to an ice chest were they recover and wait to be measured and identified.
Together with her husband George Neely, a research scientist with the aquarium, George and Lisenby came out to the Emory 18 days after the spill and collected fish samples. Since then George has returned every three months as part of a three-year study to examine the effects of the spill on fish population size, diversity, age structure and health. Selenium can cause reproductive failure in fish.
"You don’t take an adult fish and watch it die of selenium poisoning; it’s a loss of a generation of fish," George explains. "So it’s biologically dead even though it’s alive."
Shock therapy on the Emory River
To collect the fish, we begin electroshocking at the Emory River 2.1 site, right near the epicenter of the spill. The boat’s orange boom poles extend in front of the boat, dropping five steel cables into the water. The cables hang like teeth on a rake, sending 500 volts of electricity into the water. Stunned fish float to the surface where they are scooped up in a dipnet and dumped in a cooler to be "keyed out," fish scientist lingo for collecting data on fish species, length and health. After George has written the data up in her notebook the fish are released back into the water and swim away.
I’m strangely tempted to stick my hand in the charged water, like a toddler at an electrical outlet, until Neely warns me off at the pass: "That’s considerably more than sticking your finger in a socket." As if on cue a school of shad crackle out of the water like popcorn.
Exactly 210 shocking seconds later, we’ve caught 14 fish across eight species. Two of the fish exhibit signs of environment-induced stress, an eroded fin and a fungal infection.
"The biggest concern for me is just the amount of lesions and deformities we’ve seen in the fish," George says of her preliminary findings. "It’s very clear that they’ve been subject to very extreme stress which you would expect with an event [the spill] like this."
The scientists key out the species, tally their length and check their health before Alexandra releases them back into the murky water: plunk.
At our backs, the clean-up efforts of the coal ash plant are underfoot. Dump trucks, track hoes (giant backhoes on tracks), bulldozers and cranes hum and thrum, punctuated by beeps of heavy machinery, as they continue to dispose of the steel gray coal ash, as they have for the past 21 months.
Image: Gizzard shad, Dorosoma cepedianum. This fish is covered in a white fungal infection, a common sign of stress in fish. Courtesy of © Blue Legacy/Oscar Durand
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