How significant are coal-fired power plants as a source of mercury pollution?
They’re the biggest source of new mercury to the air in North America. We’ve been polluting our environment with mercury since the industrial revolution, so our soils and waters are contaminated, and they also re-emit old mercury pollution to the air. Describe how mercury from coal-fired power plant emissions moves from the atmosphere and into an ecosystem. Mercury is emitted from stacks in a number of forms, some of which are deposited nearby, and some that are transported around the globe. Most of the mercury pollution here in Maryland comes from our own power plants and power plants in states upwind, but some comes from other countries. China’s increasing use of coal is of concern. Mercury in the atmosphere returns to the land and to the surface of our water bodies in rain and in particles. It is also absorbed directly from the atmosphere by plants, and sometimes deposited as particles. All the deposition that is not in rain is collectively called “dry deposition.” You spend a lot o
