A rancher is suing an Oklahoma oil company over a pipeline that twice spilled saltwater into a creek and on land where she runs her cattle in northwestern North Dakota.

Linda Monson of Alexander said nothing but weeds have grown where Zenergy, Inc. of Tulsa, Okla., spilled salty water.

"There's nothing growing where they had those spills, and my cows still refuse to drink from the creek," she said.

Monson was one of about a dozen ranchers affected by the saltwater spill near Alexander that was discovered in January 2006. The spill has been described as the worst in North Dakota's oil history.

The saltwater, a byproduct of oil production, flooded a stock pond and a beaver dam, and flowed into Charbonneau Creek, a tributary of the Yellowstone River.

Monson said a similar spill occurred in August 2005 that never was reported to authorities.

Saltwater from the pipeline, containing water 10 times as salty as sea water, killed fish, turtles and plants along the creek after both spills, she said.

Monson's federal lawsuit seeks at least $75,000 from Zenergy.

Company officials did not return telephone calls on Monday seeking comment.

State officials last year reached a $123,000 settlement with Zenergy, said Dave Glatt, the director of the state Health Department's environmental health section.

A fine of $31,750 was suspended "for following through on their corrective action plan," Glatt said.

Glatt said the company did not report the August 2005 spill, and regulators learned of it only while investigating the spill that occurred more than a year later.

Zenergy is continuing with the cleanup, which has cost the company more than $2 million so far, Glatt said.

The company has excavated tons of contaminated soil from the spill site. It has said the creek is as clean as it was before the spill and has been repopulated with turtles and fish.

"That's my understanding, and leads us to believe the cleanup is headed in the right direction," Glatt said.

Monson and her attorney, Derrick Braaten of Bismarck, are not convinced. They worry about the long-term effect of the spills.

"One of the main concerns is that there is still saltwater underground and it's not static - it can move," Braaten said.

Monson and Braaten also said the company's cleanup operation has worsened the flow of water into the creek.

"They've cut off the main water veins that feed the creek," Monson said.