Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Managing coal combustion residues in mines

02.03.2006


Filling mines with the residues of coal combustion is a viable way to dispose of these materials, provided they are placed so as to avoid adverse health and environmental effects, says a new congressionally mandated report from the National Academies’ National Research Council. The residues left after coal is burned to generate power - often referred to as coal ash - consist of noncombustible coal matter and material trapped by pollution control devices. Enforceable federal standards are needed to guide the placement of coal ash in mines to minimize health and environmental risks, the report says.



Coal combustion in the United States leaves behind enough residue to fill 1 million railroad coal cars each year, and the volume continues to grow along with rising energy demands and improved pollution-control measures. Most of this ash is disposed of in landfills and surface impoundments, but it is increasingly being used in mine reclamation. In addition, about 38 percent of the residues are currently used to make cement, wall board, and other products. The report encourages the continued use of some residues in industrial applications as a way to reduce the amount requiring disposal.

"Because the amount of coal combustion residues is large and increasing, we should pursue productive uses for them," said Perry Hagenstein, chair of the committee that wrote the report and president of the Institute for Forest Analysis, Planning, and Policy, Wayland, Mass. "When such uses are not feasible, putting residues in mines as part of reclamation provides an alternative to landfills and surface impoundments, although potential health and environmental risks must be addressed."


Returning coal combustion residues to mines has certain advantages, the committee said. For example, the residues provide filler for mine reclamation efforts that restore land use conditions at a site, and putting these residues in mines lessens the need for new landfills. The residues may also neutralize acid mine drainage, lessening the potential for some contaminants from mines to enter the environment.

Little is known about the potential for minefilling to adversely impact groundwater and surface water, particularly over long time periods. Because information from minefilling sites is limited, the committee assessed potential risks by examining data on adverse environmental effects from surface impoundments and landfill sites. The data indicate that adverse environmental impacts can occur when coal ash containing toxic chemicals has contact with water or when the residues are not properly covered. The report recommends that minefills be designed so that movement of water through residues is minimized.

To aid understanding of risks and limit the potential for adverse effects, the committee recommends improved characterization of coal combustion residues before they are placed into mines. This would involve understanding the composition of the residues and testing the potential for hazardous chemicals to leach into the environment under all possible conditions in the target mine, particularly with respect to various pH levels. Mine sites also must be well-characterized, which includes developing a clear understanding of groundwater flow patterns.

The report also recommends a more robust program to monitor mine sites where coal residues have been placed. Currently monitoring involves testing water in wells placed around the mine sites. However, the number and placement of wells is generally inadequate, according to the committee. It suggested taking several factors into account - such as rates of groundwater flow and estimated risks from contamination - to place wells in a manner that yields early data on potential water contamination.

Under the federal Surface Mining Control and Reclamation Act, states are generally responsible for broadly regulating the management of coal combustion residues during mine reclamation. While general enough to cover putting residues in mines, SMCRA does not specifically regulate the practice, leading some states to say they lack the power for more explicit regulation. The report says that development of enforceable federal standards would give the states such authority, while allowing sufficient flexibility for adapting requirements to local conditions. Only through enforceable standards can minimum levels of protection be guaranteed nationally, the committee added.

William Skane | EurekAlert!
Further information:
http://www.nas.edu

More articles from Ecology, The Environment and Conservation:

nachricht When corals eat plastics
24.05.2018 | Justus-Liebig-Universität Gießen

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>