Fly ash is a product of burning finely ground coal in a boiler to produce electricity. It is removed from the plant exhaust gases primarily by electrostatic precipitators, or baghouses and secondarily by scrubber systems. Physically, fly ash is a very fine, powdery material, composed mostly of silica nearly all particles are spherical in shape. Fly ash is generally light tan in color and consists mostly of silt-sized and clay-sized glassy spheres. This gives fly ash a consistency somewhat like talcum powder.
While there is good agreement on how fly ash and other coal waste is generated, there is less consensus about the chemical composition of coal combustion products (CCPs) and how much danger they pose to people and the environment. According to Wikipedia, the components of fly ash vary considerably but all fly ash includes substantial amounts of silicon dioxide (SiO2) (and calcium oxide (CaO), which are common ingredients in many coal bearing rock strata. Toxic constituents depend upon the specific coal bed makeup, but may include one or more of the following substances in quantities from trace amounts to several percent: arsenic, beryllium, boron, cadmium, chromium, chromium VI, cobalt, lead, manganese, mercury, molybdenum, selenium, strontium, thallium, and vanadium, along with dioxins and PAH compounds.
Coal ash has been studied extensively for decades by universities and government regulatory agencies. The U.S. Environmental Protection Agency and other government bodies have determined that it is non-hazardous… Designating coal ash as hazardous or toxic is counter to scientific evidence and would seriously limit the current widespread uses of these materials today.
American Coal Ash Association Educational Foundation
An August 2007 draft report prepared for the [EPA] analyzed hazards associated with ponds and landfills, …the threats arise when utilities dump the waste in unlined or partially lined ponds and pits, …Indeed, the analysis determined such sites pose a cancer risk from arsenic at 900 times the level of what was deemed safe. … Some EPA scientists believe that recent toxicity data would double the assessment of the hazards.
The Center for Public Integrity
Peeling away partisan rhetoric it becomes clear that coal ash contains toxic heavy metals. Even the graph presented by the American Coal Ash Association on their website (shown here) indicates that there are higher amounts of most trace metals in fly ash (gray line in graph) than in either the surrounding West Virginia soil or the coal itself (blue and red lines). Arguments tend instead to focus on the levels of hazardous metals in the ash and on the ability to contain the flow of these metals into groundwater and surrounding soil.
An increasing amount of evidence indicates that the characteristics of coal combustion wastewater have the potential to impact human health and the environment
Many of the common pollutants found in the coal combustion wastewater (e.g. selenium, mercury, and arsenic) are known to cause environmental harm and can potentially represent a human health risk.
As EPA, the CDC and others work to resolve the question of how much heavy metal is too much, we can assemble what we do know to help assess our risks. So, for example, we do know that communities adjacent to coal ash disposal facilities have cancer rates that greatly exceed the national average. We do know that relatively small or “trace” amounts of coal ash pollutants can have serious deleterious effects on human health. (See table below.) And we do know that that a number of heavy metals are bioaccumulators, which means that the level of toxins in our bodies increases as we drink from contaminated aquifers, eat fish from contaminated streams, eat vegetables from contaminated gardens and even breath the air where pollutants have been released through burning or transport of coal.
Living in Giles county these facts hit home. The 2006 health statistics profile for our community indicates we are already exhibit a much higher level of health problems than the rest of the state or the country. In addition, pollutants in the New River have prompted the Virginia Department of Health to advise limited consumption of fish caught in the New River’s waters. If someone had tried to put a nuclear power plant in our county we would have been up in arms, but because fly ash “looks like talcum powder” we are less apt to worry about its effects. In fact, a 2007 Scientific American article reports that coal ash is more radioactive than nuclear waste-but that is far from the worst threat it poses.