ANCHORAGE (AP) -- Water samples taken from the Lower Kenai River during the peak of the sportfishing season in the past two summers have found oil pollution that exceeds the state's health standard for fish and other aquatic life.
The river near Kenai's Cunningham Park had the highest concentration of hydrocarbons, hovering near 12 parts per billion in two samples, each taken about a year apart. The state limit is 10 parts per billion.
''All of us were caught by surprise when we were plotting this data up,'' said Robert Ruffner, an ecologist with the Kenai Watershed Forum and the project's leader.
Ecologists conducting the study said a possible source is two-stroke outboard motors, but there is no direct link connecting boat motors with the increased hydrocarbon levels. Oily road runoff or leaky fuel tanks could also be a source, researchers said.
The oil-tainted samples were taken on Tuesdays in late July 2000 and 2001, when the river is teeming with red salmon and abuzz with boaters.
Hydrocarbons showed up mainly in samples taken downstream from the Sterling Highway bridge in Soldotna.
Ruffner presented the preliminary findings this week in Soldotna at the annual meeting of the American Waters Resource Association's Alaska chapter.
The $70,000-a-year water monitoring program is organized by the Watershed Forum, a nonprofit river conservation group. It is largely funded and monitored by the state Department of Environmental Conservation to gauge baseline environmental conditions on the river.
State environmental regulators say they aren't reaching any conclusions or planning specific actions as a result of the new information. The study is too new: Its data are limited to just three sets of water samples.
But the findings beg further research, especially into the possible connection between the river's midsummer oil residue and two-stroke outboard motors, said Tim Stevens, DEC's project manager.
Two-stroke engines inject oil into the gasoline to lubricate the pistons and are inefficient, coughing out as much as 30 percent of their unburned fuel in the exhaust.
Many Kenai River guides and private boat owners have switched over to four-stroke engines, which, like car motors, recirculate oil and burn cleaner, said Kenai River guide Jeff King.
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