Coal Seam Methane Gas (CBM)

What is Coal Bed Methane Gas?

Coal bed methane gas (CBM or coal seam methane), as the name suggests, is a by-product of the geological processes that created our waste deposits of coal. It's original name was firedamp because it is the most dangerous of the explosive mine gases. Some coal measures contain more gas other contain less.

Wikipedia, the free encyclopedia, defines CBM as: "Also called coal bed gas, the term refers to methane adsorbed into the solid matrix of the coal. It is called 'sweet gas' because of its lack of hydrogen sulfide. The presence of this gas is well known from its occurrence in underground coal mining, where it presents a serious safety risk. Coalbed methane, often referred to as CBM, is distinct from a typical sandstone or other conventional gas reservoir, as the methane is stored within the coal by a process called adsorption. The methane is in a near-liquid state, lining the inside of pores within the coal (called the matrix). The open fractures in the coal (called the cleats) can also contain free gas or can be saturated with water."

This coal gas can be extracted by various drilling techniques and used as the natural petroleum gas. For an authoritative review see this complete Wikipedia page Extraction of CBM.


Frequently Asked Questions - Coal Bed Methane (CBM)
(2003) Research paper Montana State University,USA. Discusses the Coal bed methane extraction technology and it's effect on surface and ground water flows as well on the soil fertility.



Environmental Hazards of Coal Gas

Promoters of the coal gas extraction take a lot of of trouble to present their fledgling industry as very "green", harmless to the environment, "the way ahead", "clean coal technology" and so on. Unfortunately, despite all the skillful spin, the reality is different. Overseas experiences, particularly those from the USA, show that gas mining is associated with numerous environmental hazards. We have to be extremely careful because the environmental damage could easily exceed any expected benefits.


Threats in General

Archived Website of the Australian Gas Alliance
(2004) A Central Coast citizen action group website. Provides many links to local and US sources of information. Particularly concerned with the effect of methane extraction on the ground water level. This website is no longer in existence. It has been recovered from internet archives.

  Letter to Bureau of Land Management, Buffalo, Wyoming, USA (
(2002) Website and environmental Submission of Powder River Basin Resource Council, Wyoming, USA: Discussion of environmental issues  by a group of local citizen presented to the state authorities. Included in their website with many interesting links.

Climate changes methane gas leaks, CO2 info

Coal bed methane alert (Sydney gas gets a mention).


Threats to Underground Water Resources




Threats to Surface Water



Possible Air Pollution


Noise Pollution




Social Effects of Coal Gas Mining

For some reasons promoters of the coal gas mining prefer to move into undisturbed areas inhabited by small rural communities. Experience overseas shows that this could have devastating effects on them for many reasons. This can be best illustrated by several streaming video clips  from Colorado and Wyoming, USA. They deal mainly with effects of the natural gas (propane) exploration  but the social and environmental effects would be very similar to those of the coal bed methane. Colorado and Wyoming  are two gas exploration boom states and their local paper Rocky Mountains News  run on 12 December, 2007 a fascinating feature entitled

"Energy rush creates haves and have-nots"

The video interviews with local residents are at the top on the right hand side of the page. They are something not to be missed because these clips  may well represent a glimpse into our future. There is, of course, one vital difference: in Australia the land owners do not get royalties from the gas companies so probably not  too many "haves" will be created here.  The Rocky Mountains scenery in the clips  is stunning and the tolerance of Americans to the environmental damage amazing. Do not miss reading the readers comments at the bottom of the page - very educational. They may be real or they may be a work of some public relation firm hired by the oil companies. There is no doubt that the social effects of gas exploration could be very complex.

CBM Development, Ranching And Agriculture  A public testimony of Nancy Sorenson a rancher from Wyoming, USA. A story of a broken dreams ...



Coal Gas Extraction in Australia

The history of coal gas mining in Australia is relatively short but quite turbulent. We are only second to the USA in commercialization of the coal gas methane resources.

In NSW there is a small gas field south of Sydney at Camden. This was originally established by Woodside Petroleum Company and subsequently sold to Sydney Gas Limited and Australian Gas Limited consortium. Sydney Gas subsequently tried unsuccessfully establish a gas field west of Wyong. At present they are trying again in the Hunter Valley Bulga-Broke area.

In Central Qeensland, where they operate under the Coal Mining Act, they are more succesful. See the article presented by the Australian Coal Association. It should be noted that they do not operate in densely populated rural residential areas.

Coal and Climate Change - Methane Capture and Use
(2007)Review paper from the Australian Coal website. Describes the commercial gas extraction operations in Queensland.


Coal Bed Methane Hazards in New South Wales
(2005)Research paper University of NSW . Critical review of some experiences from test bores at Central Coast Dooralong Valley and at Pilliga forest.


Mining Mismanagement in Pilliga, NSW

New Gas Pipeline to deliver jobs and cut greenhouse


Coal Gas and Government Departments

Governments at all levels are in difficult positions. From one side they are under pressure from the mining companies to give them unlimited access to the land under their juristriction. On the other side they are the voters who require protection of the environment and their citizen rights. They do not always succeed in taking a responsible and balanced view.


Government Cover-up



Coal Gas Extraction Overseas

The CBM industry started in the USA in the early eighties. These early days could be characterized by a complete disregard of any environmental concerns - saline waste waters were allowed to drain into rivers and escaped gas resulted in a constant smelly haze over the rangelands of Wyoming and Montana. Lately there were some improvements due to the state government regulation but there is still a long way to go. several new CBM projects are currently under consideration especially in USA, Canada and Indonesia.

This website provides a very balanced view on CBM developments in the USA.


Coal Bed Methane Monitor
(2004) A citizen action group website, Montana, Wyoming, USA. This very active site provides numerous other articles that show that life near coal methane production fields is not a bed of roses.



CBM and the Existing Coal Mines

When the coal deposits are disturbed by open cut mining the gas simply escapes into the atmosphere. In underground mines the coal gas represents a serious danger to the miners because the explosive mixture of methane and air is extremely dangerous. It has to be moved by mine ventilation systems into the open air and either released or flared. Since methane is 24 times more effective as a greenhouse gas then the carbon dioxide releasing it atmosphere is highly damaging and irresponsible. Flaring the methane is better but also a waste of a valuable resource. Extraction of the methane from the existing coal mine leases is a more attractive proposition. Both industries are therefore inexorably linked and should be treated as one.


A NEW longwall project north of Wyong A NEW longwall project north of Wyong in New South Wales has recently been submitted for project application approval – the first of many needed before an expected longwall ramp-up in 2010. Wallarah 2 Coal Project (W2CP) environment and community manager Peter Smith told International Longwall News how the project was progressing.