Unconventional hydrocarbon extraction is a potential nightmare! Toxic and radioactive water contamination and severe air pollution.
Hundreds of lorries thundering up and down our roads, 24 hour noise and light pollution.
Tens of thousands of wells, pipelines and compressor stations devastating our countryside and blighting communities.
All while accelerating climate change, and to produce expensive gas that will soon run out. So why do they want to do it?
1. Shale Gas
2. Coal Bed Methane (CBM)
3. Underground Coal Gasification (UCG)
Shale Gas is methane (natural gas) which is trapped in impermeable shale rock deep underground, unlike conventional natural gas which is in permeable rocks, such as sandstone. The gas cannot flow through the shale, so simply drilling a well, as you would for conventional natural gas, is not enough. The shale rock must be cracked to free the gas, hence the need for hydraulic fracturing (fracking). For the same reason it is necessary to drill large numbers of wells at regular intervals. To produce as much gas as a conventional gas field with a dozen or so wells, would require hundreds or thousands of shale gas wells.
Because of the much more intense nature of the shale gas extraction process it is associated with much more negative impacts than conventional drilling. These include leaking methane, water contamination, air pollution, radioactive contamination, massive industrialisation of the landscape, worsening climate change and earthquakes. Severe health effects in people and animals are beginning to mount areas where shale gas extraction is widespread. Shale gas extraction also leaks large amounts of methane (a very strong greenhouse gas) and makes available fossil fuels that would not otherwise be burnt, both significantly worsening climate change.
Coal Bed Methane (CBM)
Coal Bed Methane is methane (natural gas) trapped in coal seams underground. To extract the gas, after drilling into the seam, it is necessary to pump large amounts of water out of the coal seam to lower the pressure. It is often also necessary to frack the seam to extract the gas. There is a similar catalogue of negative environmental and social effects as with Shale Gas. This includes methane migration, toxic water contamination, air pollution, increased carbon emissions and a general industrialisation of the countryside. Impacts that are specific to CBM include depletion of the water table and potentially subsidence.
In common with other unconventional gas extraction, such as Shale Gas, CBM wells do not produce large amounts of gas per well and production declines very quickly. It is therefore necessary to drill large numbers of wells, covering a huge swaths of the landscape. CBM exploitation began in the US and over 55,000 CBM well have been drilled in the last decade or so, mostly in the western states (Colorado, New Mexico and Wyoming in particular). In Australia, where it is know as Coal Seam Gas (CSG), over 5,000 CBM wells have been drilled in Queensland in the last few years and the industry is aggressively expanding into New South Wales. In the UK CBM is more advanced than Shale Gas and full scale production may begin soon.
Underground Coal Gasification(UCG)
Underground Coal Gasification (UCG) is a process for exploiting coal that cannot be mined because the seams are too deep, thin or fractured. The process involves using the same sort of drilling technology usually used for fracking to get air/oxygen into the coal seam and then set the seam on fire. By controlling the amount of oxygen injected it is then possible to only partially burn the coal and bring the gases produced to the surface where they can be burn to produce energy. A witches brew of toxic and carcinogenic coal tars are produced in the burn cavity. The process is associated with serious groundwater contamination and massive carbon emissions.
Small scale tests of UCG have been taking place on and off since the 1930’s, particularly in the Soviet Union and United States, and have usually resulted in contamination of groundwater. More recently there have been three tests in Australia, two of which have resulted in the plants being shutdown. After only a five day burn the well at the Cougar Energy plant in Kingaroy, Queensland exploded and subsequently benzene and toluene were detected in groundwater and in the fat of animal grazing on the surface. Full scale UCG would likely involve huge plants connected to multiple gasifiers, and might be similar to tar sands extraction in its scale and impact. See Underground Coal Gasification: Hellfire and Damnation for more details.