10:05 a.m. - VALLEY CITY - State health officials say they found no environmental damage from a recent liquid fertilizer spill into the Sheyenne River.

An estimated 4,000 gallons of ammonium phosphate leaked from the Dakota Plains Cooperative tank, which is about six blocks from the river. The tank was left unlocked, and officials speculated that a vandal opened the valve.

Kris Roberts, an environmental scientist for the North Dakota Health Department, said some of the liquid reached the river through the city's storm sewer system.

When the spill happened March 23, there were large volumes of water flowing into the river from spring snow melt, and the fertilizer was diluted, he said. River testing did not show abnormal levels of ammonia or nitrogen in the water, and no fish kills were detected.

"The facility was very lucky that there was not an appreciable impact," he said. "But it was pure luck as to when it happened."

Ken Astrup, general manager of Dakota Plains, said soil testing along the spill route found contamination to a depth of six inches. Employees scraped up the dirt and built a temporary ring dike around the fertilizer tank.

Roberts said the cooperative could be fined up to $5,000 for improperly reporting the spill. The company reported the spill to a local agriculture official, not to the Health Department, as rules require, officials said. The Health Department did not learn of the spill until a week after it happened.