By Bob Moen / AP
Cheyenne, Wyoming – New government research indicates that some coal-bed methane water flowing into the Powder River of northeast Wyoming contains potentially dangerous levels of ammonia.
But the study also found that vegetation in a drainage channel can absorb dissolved ammonia and microorganisms can transform it to harmless nitrogen gas.
USGS scientist Richard Smith says the study's findings are not so significant that it would raise any red flags about coal-bed water discharges.
But he says more study is needed to determine what happens to the ammonia after it enters the Powder River and how the practice of impounding the coal-bed water affects ammonia levels.
The quality of coal-bed water discharged in Wyoming's Powder River Basin has been an issue with environmentalists and the state of Montana, where the Powder River flows from Wyoming.