Featured Research

from universities, journals, and other organizations

Putting Coal Ash Back Into Mines A Viable Option For Disposal, But Risks Must Be Addressed

Date:
March 5, 2006
Source:
The National Academies
Summary:
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.

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.

The study was sponsored by the U.S. Environmental Protection Agency. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.


Story Source:

The above story is based on materials provided by The National Academies. Note: Materials may be edited for content and length.


Cite This Page:

The National Academies. "Putting Coal Ash Back Into Mines A Viable Option For Disposal, But Risks Must Be Addressed." ScienceDaily. ScienceDaily, 5 March 2006. <www.sciencedaily.com/releases/2006/03/060305094149.htm>.
The National Academies. (2006, March 5). Putting Coal Ash Back Into Mines A Viable Option For Disposal, But Risks Must Be Addressed. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2006/03/060305094149.htm
The National Academies. "Putting Coal Ash Back Into Mines A Viable Option For Disposal, But Risks Must Be Addressed." ScienceDaily. www.sciencedaily.com/releases/2006/03/060305094149.htm (accessed April 24, 2014).

Share This



More Earth & Climate News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
New Pictures of Ship That Sank in 1888

New Pictures of Ship That Sank in 1888

AP (Apr. 24, 2014) Federal researchers have released new images of the City of Chester, a steamship that sank in San Francisco Bay in 1888. Researchers recently found the shipwreck while mapping shipping routes. (April 24) Video provided by AP
Powered by NewsLook.com
Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Risk of Asteroid Hitting Earth Higher Than Thought, Study Shows

Reuters - US Online Video (Apr. 23, 2014) A group of space explorers say the chance of a city-obliterating asteroid striking Earth is higher than scientists previously believed. Deborah Gembara reports. Video provided by Reuters
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins