Dirty energy cleanup shifts burden to building materials

James Vallette | January 20, 2012

The compartmentalization of environmental policies can create escape valves for pollution.  Regulations that do not reduce toxic inputs lead to a transfer of hazards. We have seen this, for example, with solid waste regulations. In the 1980s, when new regulations forced major disposal practice changes, waste generators took advantage of a lack of export controls.  They followed the path of least resistance and tried to ship waste to Africa, Haiti, and Bangladesh.

We are seeing a similar story unfold with pollutants generated by coal-fired power plants. The EPA took a huge, and long-awaited, step toward controlling toxic air emissions from coal power plants last month.  It released rules that, when fully implemented by 2016, will limit the air emissions of toxic contaminants of coal, such as mercury, arsenic, chromium, and sulfur dioxide.

Since coal fired power production is going to continue, these contaminants have to go somewhere.  While one outlet (the smokestack) is under the regulatory gun, another outlet lies wide open: the unregulated commercial use of solid waste captured from pollution control devices.

Many power generators have equipped newer plants with flue gas desulfurization (FGD) units to comply with EPA air rules, existing and forthcoming.  FGD pollution control devices capture and concentrate many of the EPA-targeted air emissions. And wastes from these FGD units are coming to a house, office, hospital, or school near you. In fact, they probably already have.

FGD waste – marketed as “synthetic gypsum” – has become a common ingredient in some building materials, particularly wallboard (also commonly known as drywall). The EPA says it “strongly supports this practice.”

As the new air rules are implemented, we can expect more transfers of air pollutants into building materials. So far, the EPA has declined to regulate this material as “hazardous waste.”

The material flow is as unregulated as when the city of Philadelphia dumped its incinerator ash on a beach in Haiti, back in 1988.  Then, too, waste traders tried to convince residents that ash makes a good “building material.”  

Residues collected from FGD units are now the leading material used in wallboards. Over the past decade, wallboard manufacturers moved most of their production plants from mines to coal-fired power plants.  The lower cost of FGD gypsum[1] compared to mined material, and incentives to incorporate recycled ingredients (including waste products) into building materials, drove the dramatic – and little recognized – transformation of North American-made wallboard.

Commodification disperses contaminants downstream. The first point of dispersal is in building material production processes, where the heating of FGD gypsum can release toxic heavy metals.  For a while, the toxicants may then be contained within the physical structure of the finished material.  But encapsulation lasts only so long. Ultimately, buildings and building materials are demolished and discarded or recycled.   Drywall equals about 15% of all construction and demolition (C&D) debris.  This debris winds up in new drywall, landfills, and even in some agricultural applications.

The subject of coal waste product commodification has been a side issue in coal fired energy debates – so far.  The transfer of toxic coal contaminants into the indoor environment will grow.  As time and mass increase, impacts could too, and we will begin to more fully understand the scope of shifted burdens.   The unregulated experiment has barely begun.  


[1] A 2004 Ohio State University estimate put the price of synthetic gypsum at $7/ton, compared to $12.75/ton for natural gypsum. http://ohioline.osu.edu/anr-fact/0020.html