Coal combustion wastes have numerous aliases…. According to the American Coal Ash Association, EPA started using the term “coal combustion products (CCPs)” in 2002 (1). In the past (and still on occasion), EPA used the terms “fossil fuel combustion wastes (FFCW)”, “coal combustion byproducts (CCBs), and the broader “special” and “Bevill wastes”. <See EPA’s fossil fuel combustion waste website at http://www.epa.gov/epaoswer/other/fossil/index.htm>.

DOE’s National Energy Technology Laboratory calls these byproducts “coal utilization byproducts (CUBs), preferring the term “utilization” over “combustion” because “it accounts for gasification, which also produces solid by-products which must be managed” (2). EPA’s Office of Research and Development studies hazards of coal combustion wastes and calls them “coal combustion residues (CCRs)”. DOI’s Office of Surface Mining Reclamation and Enforcement uses “coal combustion byproducts”, as defined in 42 U.S.C. 13364(a), to describe coal combustion wastes in their recently published proposal for placement of coal combustion wastes in active and abandoned coal mines (3).

The above list of aliases used by various federal government agencies doesn’t include the more specific terms used to describe the different categories of coal burning waste such as fly ash, FGD sludge, bottom ash, etc., or even the list of acronyms (PFA, etc.) that can be found in use internationally. This can make it difficult for concerned communities to find relevant information on how these wastes are being used, regulated, managed, or what the potential health and environmental consequences may be from those various management or disposal schemes.

People concerned about the (mis)management of coal combustion wastes might do well to try to keep up with all these changes… otherwise, little changes in terminology here and there, department by department and agency by agency, can gradually change the landscape of regulation and public acceptance before it’s even realized.

Efforts to change perception seem to be relentless, even creating seeming internal inconsistencies between project start and final report. A recent report by the National Research Council, partly authored by the Committee on Mine Placement of Coal Combustion Wastes, and published by the National Academies Press, uses the term CCRs, stating that “although the term CCWs was used in the statement of task, after much discussion the committee chose to use the term CCR for the purposes of this report.” (Summary p. 3, <http://books.nap.edu/openbook.php?isbn=0309100496>)

The term “CCRs” is getting closer to what industry wants, but it’s still not as preferred as “CCPs”….

In fact, the industry has written whole papers on terms that are encouraged or discouraged for their apparent bias <www.mcrcc.osmre.gov/PDF/Forums/CCB3/2-1.pdf>. According to a January 2007 presentation to EPA by David Goss of the American Coal Ash Association, “although ash and CCPs are terms often used interchangeably, CCPs is the industry preferred terminology” (4).

Oh, so you mean that we should assume all coal combustion byproducts should be reused, no matter how it’s done or where they go, and that EPA should help you promote your waste material as a product so your industry can profit by avoiding disposal costs of this enormously high volume dangerous byproduct? I’m a supporter of recycling and reuse – when it’s safe – as much as the next person. I also strongly believe in avoidance of making the waste in the first place. Just because you recycle something – anything- it doesn’t mean that its original production was good for the environment, or that it’s original raw material mining or manufacture didn’t lead to its own waste. If I recycle X number of pounds of something per year, I haven’t done as much for the environment as if I had just not consumed those materials in the first place. Reusing coal combustion waste doesn’t make coal “clean” – it doesn’t retroactively reverse the impacts of mountaintop removal mining, it doesn’t stop the coal-cleaning waste, it doesn’t change the emissions from transporting the coal or the ccw to use, and it certainly doesn’t make the combustion process any cleaner.

Let’s watch to see what the final rule on placement of CCBs in coal mines terms these wastes — will DOI in the end change their terminology and use the industry-preferred term (CCPs)? (As an aside — throwing CCWs away in active or abandoned coal mines seems to me to be about as close to disposal vs. use as you can get.)

The industry has encouraged use of the term “product” with the hopes of alleviating public and government concern and negative associations with recycling “wastes” or “byproducts” into roads and buildings and consumer products. People who care about clean water and a clean environment can watch industry actions on this one — and take action. Write letters to the editor to clarify what these wastes are when articles appear touting supposed “beneficial use of coal combustion products”. Submit comments on proposed federal regulations or at hearings, and call the agencies out for their own industry-sensitive bias when you see it.

Coal combustion and coal gasification processes produce byproducts — high volumes of extremely variable wastes that vary by combustion process, flue gas treatment type, feed coal content or mix, pollution control mechanisms, etc. Regulations are needed to improve health and safety of this industry’s waste. Calling these byproducts “products” and selling them to roadbuilders, agricultural, or other use doesn’t change what they are… waste.

Notes

1. American Coal Ash Association (ACAA) website includes a discussion of EPA’s transition to the industry-preferred terminology on these wastes: http://www.acaa-usa.org/FAQ.htm

2. DOE Topical Report 24, “Clean Coal Technology: Coal Utilization By-Products”, August 2006, p.6 http://www.netl.doe.gov/technologies/coalpower/cctc/topicalreports/pdfs/Topical24.pdf

3. DOI OSMRE, Proposed Rule: Placement of Coal Combustion Byproducts in Active and Abandoned Coal Mines, March 14, 2007, Federal Register Vol.72, no.49, p.12025

4. Coal Combustion Products Basics: Presentation to EPA OSW, January 23, 2007, by David Goss (ACAA) www.epa.gov/epaoswer/non-hw/imr/irc-meet/05-coal.pdf

(Update: If EPA web server not properly working, click here to see text only version of above presentation. This presentation was part of a series of presentations to EPA by the Industrial Resources Council.)

Coal-burning utilities must be pretty excited about all the buzz they’re getting these days from the most unlikely of sources: green building enthusiasts. Somehow, with a lot of promotion and a little help from the government, coal-fired power plants are able to avoid costly disposal and waste management of their toxic byproduct, fly ash, by increasing the use of coal fly ash in cement admixes and concrete construction projects. Incredibly, after extracting the coal from the earth, processing it, burning it, and then hauling the captured solid leftovers from the coal smoke to cement and concrete suppliers, coal-burning industries are getting an environmental credit for reducing greenhouse gases and recycling a waste product. Let’s review how this happened….

Activities like coal mining and coal burning emit tons of greenhouse gases into the atmosphere. So does the process of making cement for concrete. Coal fly ash, a waste byproduct from burning coal, has certain cementitious properties (in addition to mutiple toxic elements like mercury) that mean that in some applications, it can be used as a partial replacement for energy-intensive Portland cement used in concrete. The American Coal Ash Association estimates that over 71 million tons of coal fly ash were produced in the U.S. in 2005 (1), making this toxic industrial waste an expensive waste management liability, unless someone else can be convinced to buy or use the waste (2) . This is where EPA and DOE weigh in. EPA conducted a skewed “comparison” of the greenhouse gas emissions from Portland cement raw material mining and manufacture, and the greenhouse gas emissions from using the coal burning byproduct fly ash (while specifically not including emissions from burning the coal to make the fly ash or from mining activities to obtain the coal in the first place)(3). EPA omitted greenhouse gas emissions from hauling, burning, or mining coal in their skewed comparison between coal burning and virgin cement manufacture emissions, resulting in a popular false claim that replacing Portland cement with coal fly ash reduces greenhouse gas emissions by one ton for every ton of Portland cement replaced (4).

While this analysis on its own is inherently flawed (see related page on the calculations), it also avoids discussion of the risk involved in adding a toxic industrial waste material to infrastructure and consumer products. Buildings and other projects constructed with coal fly ash cement are not labeled. People may not know what toxics could be volatilizing into the air from within the cement walls of their school or workplace, nor will demolition or construction crews be advised during building tear-down or construction that the dust coming up from the work site may contain fine particles laced with mercury, selenium, radium, chromium, lead, etc. There are no plans to label or treat infrastructure projects that handle drinking water sources differently, just as there are no health-based testing standards for these materials (current ASTM standards only address engineering properties of fly ash cement projects).

In addition, the entire process is built upon the continued burning of the dirtiest fossil fuel – coal. Increasing fly ash use and promoting fly ash cement as a “green” product ignores (greenwashes) enormous quantities of greenhouse gas emissions from burning coal, as well as the health of people who live near coal burning power plants, the people who will handle the fly ash cement, and the people who will be exposed to these fly ash cement construction projects. Giving environmental credit to these industries promotes polluting practices at the expense of the global climate and human and ecological health.

Coal fly ash is not a green construction material.

Sources:
1. http://www.acaa-usa.org/PDF/2005_CCP_Production_and_Use_Figures_Released_by_ACAA.pdf
2. The U.S. Department of Energy and EPA are funding projects to increase or promote utilization of coal combustion waste in many applications, including building, road construction, carpet backing, agricultural soil application, FGD gypsum wallboard, etc. DOE’s website cites a goal of increasing coal utilization byproduct use by 50% by 2010, in order to realize potential economic benefits in the range of $500 million to $1 billion < http://www.fossil.energy.gov/programs/powersystems/pollutioncontrols/overview_coalbyproducts.html>.
3. http://www.epa.gov/climatechange/wycd/waste/downloads/FlyAsh_11_07.pdf
4. Actually, EPA’s claims on ghg savings vary… see EPA Office of Solid Waste Director’s speech to American Coal Ash Association 2003 Annual Conference citing ton-for-ton savings <http://www.epa.gov/epaoswer/osw/conserve/speeches/c2p2.pdf> and C2P2 factsheet citing .8 tons CO2 saved per ton Portland cement replaced with fly ash <http://www.epa.gov/epaoswer/osw/conserve/c2p2/cases/burnout.pdf>, while the Department of Energy cites savings of .8 tons of CO2 for every ton of fly ash used in concrete <http://www.fossil.energy.gov/programs/powersystems/pollutioncontrols/overview_coalbyproducts.html>.

Recently, while researching Radium-226 incidence in fly ash, I discovered a green building (buildinggreen.com) website that had posted the following excerpt from EPA’s “Cement and Concrete Containing Fly Ash; Guideline for Federal Procurement” as published in the Federal Register / Vol. 48, No. 20 / Friday, January 28, 1983 / Rules and Regulations:

Regarding hazards of using flyash in concrete:

“Findings to date indicate that little, if any, fly ash exhibits characteristics defined as hazardous in the Federal regulations. Therefore, Subtitle C regulations will have no significant impact of the use of fly ash in cement and concrete.

A few commenters suggested that EPA limit the use of fly ash in concrete, restricting its use in potable water sources or in storage areas for food. The rationale given for these suggestions was the potential for leaching of trace metal elements out of the fly ash. The commenters provided no documentation as to the likelihood or extent of leaching when fly ash is used in concrete.

While it is true that fly ash contains trace amounts of certain elements, which can be toxic in larger concentrations, it is unlikely that fly ash as used in concrete would exhibit leaching characteristics. First, the permeability of concrete containing fly ash is negligible compared to the permeability of fly ash as typically disposed. This reduced permeability prevents water or other liquids from penetrating concrete and providing a leaching medium through which contaminants could travel.

Second, when used in concrete, fly ash becomes an integral part of the final product. The surface area of individual fly ash particles, from which leaching of trace constituents takes place, is so greatly reduced in this application as to be almost nonexistent. It is not possible through conducting leaching tests or raw fly ash to estimate the leaching, if any, which would take place in a concrete containing fly ash. Thus, the commenters suggestion that dams and pipes not be constructed using fly ash appears to have no technical basis.

(c) Radioactivity Issues. At the same time as original proposal of the hazardous waste regulations (December 18, 1978), EPA issued an advance notice of proposed rulemaking that it was considering establishing 5 picocuries per gram [pCi/g] of radium-226 as a criterion for listing wastes as hazardous. The notice also requested comment on other criteria which might tend to affect the radiation hazard. Among these is the emanation rate of radon from the waste. The agency has, at this date, taken no further action on this proposed rulemaking to establish general criteria for hazardous radioactivity levels in wastes.

Where resource recovery is practiced, an important consideration in assessing the hazard is the proposed use of the waste material. While some proportion of fly ash generated in the U.S. has more than 5 pCi/g of radium-226, the physical structure of fly ash is such that its contribution to radiation exposure is probably less than that of most normal constituents of concrete which generally fall below this level. This is explained below.

A few commenters expressed concern to EPA that fly ash used in the construction of habitable structures could pose a threat to public health due to radioactivity. The source of the radiation threat is due to radium-226, a radioactive isotope which occurs naturally in soil, sand, and mineral deposits as well as in fly ash. The radium-226 content of soil generally ranges from .2 to 3 pCi/g. Limited measurements of radioactivity in cement show that the redium-226 content of cement can be as high as 5 pCi/g, but typically averages close to 1 pCi/g. Limited measurements of fly ash presently generated in the U.S. show a radium-226 content ranging from 1 to 8 pCi/g with an average of roughly 4 /Ci/g.

There are two pathways of radiation exposure from radium-226 in building materials. The pathway of primary concern is from inhalation of radon-222 and its short-lived decay products. Radon-222, an inert gas with a radioactive half-life of 3.8 days, is the first generation decay product of radium-226. Because it is an inert gas, it can readily migrate from the building material into the indoor air of a home. Although the rate at which radon is created within a building material is proportional to its radium content, the intrinsic structure of the material may, in some cases, prevent most of the radon from escaping. When air containing radon and its radioactive decay products is breathed for long periods of time, a person’s risk of lung cancer is increased.

Gamma radiation from radium-226 and its decay products is the other exposure pathway. The amount of gamma radiation emission from a building material is proportional to its radium content, but the total exposure a person receives will also depend on other factors such as shielding, distance from the material, and exposure time. Exposure to gamma radiation results in an increased risk of many types of cancer.

When fly ash is used as a partial cement replacement in concrete, the fly ash content of the final concrete product is between 2 and 3 percent (assuming a 15-25 percent cement replacement rate and an 8 to 1 ratio of aggregate and water to cementitious material). Since the average radium-226 content of fly ash exceeds that of cement by a few pCi/g, the use of fly ash as a cement replacement in habitable structures will, on the average, result in a slight increase in the gamma radiation exposure to people (less than a milliroentgen per year). However, in some instances, where fly ash with a lower than average radium content replaces a cement with a higher than average radium content, the result would be less gamma radiation exposure.

The use of fly ash as a cement replacement will also affect the quantity of radon emitted by the building material. Although the rate at which radon is created is directly proportional to the radium content, other factors may inhibit radon emanation from a material. Because fly ash is produced at high temperatures, it has a glassy structure which keeps most of the radon from escaping. The fraction of radon which escapes from fly ash (emanation fraction) has been measured at no more than a few percent. In contrast, typical soil and soil like materials tend to have an emanation fraction in the neighborhood of 20 percent. Thus, although fly ash on the average, has a greater radium content than the cement it replaces, the use of fly ash as a partial cement replacement is likely to reduce the radon gas contribution of the final concrete product.

During the proposal period for this guideline EPA has been investigating this issue more thoroughly. Tests recently conducted for EPA substantiate the conclusions above, i.e., that the radon emanation rate of fly ash in its raw state and as used in concrete is only a few percent compared to the absolute radium concentration. Thus, while fly ash use in cement would, on the average, result in a small increase in gamma radiation exposure, this small increase in gamma exposure is likely to be offset by a decreased radon exposure. In light of this, EPA believes that the use of typically-occurring fly ash in concrete does not constitute a significantly different radiation risk, than the risk from the cement it replaces, and neither of these is significantly different from the radiation risk posed by common soil.”

While I was familiar with the USGS statements on radiation in coal fly ash, I was not familiar with many instances where EPA had discussed the potential radiation exposure to people in buildings constructed of fly ash concrete. My curiosity piqued, I visited EPA’s Comprehensive Procurement Guideline website for cement and concrete products. There, I found a few standards for engineering properties and a link to a database of manufacturers and suppliers of fly ash containing materials, but the links to additional product specifications and technical background were missing. A copy of the site from April 2006 reveals that EPA used to link to additional technical background, including information on the Federal Register notice excerpted above. Why would EPA remove this background information from its website?