Even though there's great uncertainty about the role of nature versus irrigation in selenium contamination west of Casper, the Natrona County Conservation District is moving at full speed to minimize further contamination.

Rather than wait years and spend millions of dollars to pin down the scope and causes of the problem, Jerry Eichorn, chairman of the district, said, "We decided to fix it as best we could." Now embarked on a three-year watershed plan, the district is steadily converting from flood-irrigation to sprinkler-irrigation in order to minimize deep percolation of selenium-laden water in irrigated soils. It also plans to line or enclose all canals and lateral lines to minimize seepage and will work to educate suburban neighbors about water conservation.

That was the message Thursday night, during the "Common Waters" lecture series presented by the University of Wyoming and Casper College. The focus of the evening was how to deal with selenium contamination in water coming off irrigated lands west of Casper.

As Eichorn explained it, the irrigators would have had to adopt such best-management practices anyway. So they figured they might as well tackle the problem right away, he said.

Selenium is an element that aids human and animal health in small amounts but can create problems in larger doses. It occurs naturally in soils near Casper and is concentrated in underlying marine shales - especially the Cody shale formation. Because of federal irrigation projects launched in the 1930s - Seminoe and Alcova reservoirs - the federal Kendrick Project has leached selenium out of shales and soils and concentrated it in amounts that can harm wildlife.

The Kendrick district operates on about 24,000 acres. Fish and waterfowl in the area have been found with elevated amounts of selenium in their bodies. Birds especially have experienced poor egg hatchability, embryo mortality and deformities.

The watershed plan developed jointly by the Casper-Alcova Irrigation District and the Natrona County Conservation District stems from a decision made in June 2000, Eichorn said. Regulations governing selenium could be developed by the state's Department of Environmental Quality and the federal Environmental Protection Agency, or local irrigators could develop their own watershed plan. Aided by the Wyoming Association of Conservation Districts, the local districts decided to do their own plan, Eichorn said.

Steve Jones, attorney for the Wyoming Outdoor Council (WOC), and Bobby Frank, executive director of the Wyoming Association of Conservation Districts (WACD), agreed that lawsuits filed in recent years have focused attention on the issue of nonpoint-source pollution. Unlike pollution that enters a stream from a single source like a pipe from an industrial plant, nonpoint-source pollution is from diffuse sources, they said.

WOC has been pushing for a regulatory approach in dealing with nonpoint-source pollution like selenium contamination, while WACD has pushed for local planning. Both approaches seek the same goal, they said.

"I hope this works," Jones said, though he expressed reservations about long-term results.

There might even be a way to turn the selenium problem into a profit for local irrigators, explained water consultant Rik Gay, of Lost Iguana Consulting. First, selenium is increasingly recognized as an important trace mineral in human and animal health. Some plant crops are good at pulling selenium out of the soil and concentrating it, he said. Such selenium-enriched crops could be sold, he added.

"We're going to look at a variety of crops," Gay said, such as feed for cattle, wheat and perhaps seed grass. "That would enable us to get rid of a problem by spreading it where it is needed."

One crop that's unsuitable for selenium uptake, Gay noted, is alfalfa, which releases selenium into the air.

The next program in the series is Oct. 2, when "Common Waters" looks at a ranch creek, and taps the expertise of Bates Hole residents and officials from the state Department of Environmental Quality and the U.S. Bureau of Land Management.