A fishy solution?
By BECKY BOHRER
Associated Press writer
with Star-Tribune reports
Saturday, June 4, 2005 2:00 AM MDT
SHERIDAN -- Ever since developers learned how to tap coal seams in the Powder River Basin for natural gas, they've struggled with what to do with the brackish groundwater that comes out first. A fish may be the answer.
Water is being pumped from coal-bed methane wells in rural northern Wyoming to John Woiwode's tilapia farm in an area where cattle roam. About 1,300 of the small, pink fish currently delight in the water -- flipping, flopping and pooping in it.
It's the squiggles of poop that interest researchers like Woiwode, who want to see if the waste could help make the water into a more usable asset.
"The implications are profound," said Woiwode, who's spent the past several years studying the role fish could play in alternate uses for methane wastewater. "If there's a potential to get this whole discharge issue shifted from being an industrial pollutant to an agricultural application, this is very significant."
Woiwode's previous work, in greenhouse tests, showed promising results. It indicated that using fish manure on plants watered with methane wastewater could help promote plant growth, increase the uptake of sodium into plant tissue and even change the structure of the soil, improving water infiltration.
This is key, he said, because one of the leading concerns with saltier water is that it can harm soil and growing conditions, essentially gumming up or sealing off topsoil. But if water not used by the plants can percolate below the root zone, and move the sodium farther down -- as the tests using fish manures indicated -- this isn't an issue, he said.
"Once it's past the root zone, you have productive soil that can be sustainable for an indefinite period of time," Woiwode said.
He's planning to expand the work to field tests near Sheridan beginning this summer to see if the results can be replicated in the area's heavy, clay soils. Researchers plan to plant eight varieties of plants, some salt-loving species, others not. A range of water treatments, including spring water and raw methane wastewater, will also be applied.
"We would hope this would be a win-win-win for all parties," Woiwode said.
The wastewater conundrum
One of the biggest issues surrounding coal-bed methane development -- and hindering it in some cases -- has been what to do with the water. To tap coal-bed methane, large amounts of groundwater must be pumped out to ease the pressure holding the natural gas in coal seams. Depending on the area from which it comes, the water can be salty, and if not treated or monitored closely, it could damage crops or soil, some experts and conservationists say.
Some companies are treating the water or soil so farmers and ranchers in the basin can use it for irrigation. But that can be an expensive option.
Other options include discharging the water into streams, an option that requires a permit, building livestock ponds and keeping it in large pits. Jill Morrison, an organizer with the Powder River Basin Resource Council, a conservation group, said it is difficult to deal with all the water given the sheer volume of it and the rate of development in the mineral-rich region.
Larry Munn, a professor of soil science at the University of Wyoming, said there are no easy answers.
"Most of it is suitable for livestock as drinking water, but the volume required for that is fairly small compared to the amount (being) produced," he said.
Woiwode, who holds a Ph.D. from the University of Minnesota, is a fisheries expert and runs a fish lab at Sheridan College. College Dean Jim Bennage, in response to questions over the issue of methane discharge water, talked to a large number of people about the concerns.
"Jim{M3 asked if our staff could research public concerns regarding the effects of fish in CBM water on human health," Woiwode said.
In 2001, Woiwode's Jackson-based company, AquaMatrix International Inc.,{M3 researched the suitability of methane discharge water for raising fish from a human health perspective, because of a general perception that this water was "tainted."
"If the water was somehow{M3 tainted, consumption of anything in it{M3 could be detrimental to human health," Woiwode said. "I wanted to test that theory."
In research supported by the U{M3.S{M3. Department of Agriculture, he raised rainbow trout in methane wastewater to determine the levels of heavy metals and hydrocarbons in the fish. All Food and Drug Administration-targeted heavy metals, including arsenic, cadmium, chromium, lead, mercury and nickel, were found to be below detectable limits in the edible portions of the fish flesh, he said.
The results provided a "clean bill of health," he said.
The research then moved to the possibility of commercial fish production using methane discharge water, as well as improving crop production with fish manure.
Beneficial uses
For Woiwode's latest project, thousands of gallons of coal-bed methane water are being taken from wells dotting a local rancher's land to the fish facility. A 15-foot-wide tank that is home to most of the fish there is heated to a comfortable 83 degrees for optimal growing conditions, he said. Their waste ultimately is stored in a lined pit outside, that also contains excess methane wastewater, for use on the test plots.
Dan Smith, interim director of the university's Sheridan Research Extension Center and an agronomist involved with the project, said researchers have several goals. Those include seeing whether fish manure minimizes salt buildup in soils irrigated with methane water and which crops could be grown, or perhaps thrive, using that method.
"This trial here will tell us a little more about how these things will fare in this type of environment," he said. If it's successful, it would still have to be adapted to the particular soils in a given area. Soil types vary widely in the basin.
Marathon Oil Co. operates the wells being tapped for the project, and the company's Dave Searle said the firm is as interested as anyone in the results.
"A lot of people, I don't think, understand how much science we try to explore," he said.
Rancher Roger Brinkerhoff, who has land involved in the project, said he's interested in more beneficial uses for the water.
"If the grass comes back, you're happy," he said.
If it works, Woiwode said the project could be a winner for all involved. He said it could lead to higher-value irrigated crops for landowners, provide another water disposal option for energy companies and give his company another way to raise tilapia.
So far, it will take about 1,000 pounds of fish, which weigh 1.5 pounds to 2 pounds fully grown, to produce enough poop to irrigate an acre of land. Researchers hope to have up to 3,000 fish at the facility later this summer, and Woiwode said the work should be economically viable in the future if all parties cooperated.
But he believes this is doable and that the project could provide a sound alternative to storing or wasting the water.
"I don't see it as the be-all and end-all or the silver bullet," he said. "We're trying to build an agronomic model."
Tapping the tilapia market
* About the fish: Native to North Africa, tilapia are a fresh-water fish that weigh 1.5 pounds to 2 pounds fully grown and are known for their mild and sweet flavor, their firmness and ease of preparation.
* Demand: There's a big market for the small fish, which are now farm-raised all over the world, John Woiwode said. More than 200 million pounds were eaten in the United States last year, but just a fraction of that was produced domestically.
* Wyoming connection: Woiwode said his company, AquaMatrix International Inc., developed a method by which the fish could be raised in water from coal-bed methane wells. It is interested in tapping the regional tilapia market. Nearby Sheridan College has a fish processing facility that could be used in the effort, he said. |
