The Iowa Department of Natural Resources says it’s taking steps to address concerns about mercury buildup in Iowa lakes and rivers. D-N-R air quality information specialist Brian Button says mercury is something that’s been around awhile. He says mercury is a trace substance in coal and as utility companies burn coal, mercury has slowly been building up in the environment for decades. Button says the D-N-R in June issued the first air permit that requires mercury reduction to MidAmerican Energy for its new Council Bluffs Energy Center. He says they’ll use a material like activated charcoal injected into the hot gases coming out of the plant and it will absorb the mercury and be filtered out before the gases leave. Button says the system will reduce mercury emissions by 83-percent. Button says it’s part of a growing trend toward reducing mercury emissions. He says it will help cut mercury, and he says wind power is also a way to cut mercury emissions, and says Iowa is a leader in wind energy. The Council Bluffs is expected to be operational in 2007.